APPLIED KINESIOLOGY RELATED RESEARCH INFORMATION IN PEER REVIEWED JOURNALS

-- Edited by Scott Cuthbert, D.C.

A method of testing muscular strength in infantile Paralysis, Martin EG, Lovett RW.  

JAMA. 1915 Oct 30; LXV(18):1512-3.

Certain aspects of infantile paralysis with a description of a method of muscle testing, Lovett RW, Martin EG.

JAMA .1916 Mar 4; LXVI(10):729-33.

Myotendinous alterations and effects of resistive loading in old age, Narici M, Maganaris C, Reeves N.

-- Institute for Biophysical and Clinical Research into Human Movement (IRM), Manchester Metropolitan University

Scand J Med Sci Sports. 2005 Dec;15(6):392-401.

Abstract: The loss of muscle mass associated with ageing only partly explains the observed decline in muscle strength. This paper provides evidence of the contribution of muscular, tendinous and neural alterations to muscle weakness in old age and discusses the complex interplay between the changes of the contractile tissue with those of the tendinous tissue in relation to the mechanical behavior of the muscle as a whole. Despite the considerable structural and functional alterations, the elderly musculoskeletal system displays remarkable adaptability to training in old age and many of these adverse effects may be substantially mitigated, if not reversed, by resistive loading. The interplay between these muscular and tendinous adaptations has an impact both on the length-force and force-velocity relationships of the muscle and is likely to affect the range of motion, rate of force development, maximum force development and speed of movement of the older individual.

Erector Spinae and Quadratus Lumborum Muscle Endurance Tests and Supine Leg-Length Alignment Asymmetry: An Observational Study, Knutson, G., Owens, E.

J Manipulative Physiol Ther , 2005;28(8):575-581

Objective : To determine if there is an association between supine leg-length alignment (LLA) asymmetry and the endurance of the erector spinae (ES) and quadratus lumborum (QL) muscles. Methods : Forty-seven subjects (21 women; average age, 36 years old) were tested for ES endurance using the Biering-Sorensen (B-S) test, and 69 (31 women; average age, 34.5 years) were tested for QL endurance. Subjects were examined for supine LLA and tested for ES and QL muscle endurance. The muscle endurance times were compared against those who did and did not demonstrate LLA asymmetry and the side of the "short leg." Results : In the B-S test, volunteers with LLA asymmetry (n = 27) had a mean endurance time of 89.7 seconds (SD, 43.3), and the no-LLA asymmetry group (n = 20) had a mean endurance time of 161.5 seconds (SD, 57.1), a significant difference (P < .001). In the QL test, after correction for the effects of sex and exercise, those with a right "short leg" (n = 22) had a right QL endurance time of 25.9 seconds (SE, 4.2) and a left QL endurance time of 34.7 seconds (SE, 4.3). The right QL endurance time was significantly different from those subjects with balanced legs (P = .001). Those with a left "short leg" (n = 20) had a left QL endurance time of 28.6 seconds (SE, 4.7) and a right QL endurance time of 38.1 seconds (SE, 4.5). Both QL endurance times were significantly different from those with balanced leg-length (P = .002 and .016, respectively). Conclusion : This study suggests that, using the B-S test, the group of volunteers who demonstrated a commonly used sign of subluxation/joint dysfunction, supine LLA asymmetry, had a decreased endurance times over those who did not. The QL endurance tests showed that the QL muscle ipsilateral to the supine short leg had significantly decreased endurance times over the same-side QL fatigue times in the no leg-length asymmetry group.

Spinal manipulation alters Electromyographic activity of paraspinal muscles: a descriptive study, DeVocht, J., Pickar, J., Wilder, D.

J Manipulative Physiol Ther, 2005;28(7):465-471

Objective : To examine the effect of spinal manipulation on electromyographic (EMG) activity in areas of localized tight muscle bundles of the low back. Methods : Surface EMG activity was collected from 16 participants in 2 chiropractic offices during the 5 to 10 minutes of the treatment protocol. Electrodes were placed over the 2 sites of greatest paraspinal muscle tension as determined by manual palpation. Spinal manipulation was administered to 8 participants using Activator protocol; the other 8 were treated using Diversified protocol. Results: Electromyographic activity decreased by at least 25% after treatment in 24 of the 31 sites that were monitored. There was less than 25% change at 3 sites and more than 25% increase at 4 sites. Multiple distinct increases and decreases were observed in many data plots. Conclusion: The results of this study indicate that manipulation induces a virtually immediate change, usually a reduction, in resting EMG levels in at least some patients with low back pain and tight paraspinal muscle bundles. In some cases, EMG activity increased during the treatment protocol and then usually, but not always, decreased to a level lower than the pretreatment level.

Cranial and Other Chiropractic Adjustments in the Conservative Treatment of Chronic Trigeminal Neuralgia: A Case Report, Pederick, F.

Chiro J Aust, 2005; 35:9-15.

ABSTRACT : Trigeminal neuralgia, sometimes called tic douloureux , is characterized by episodes of electric-shock-like pain in areas of the face where branches of the trigeminal nerve are distributed. Medical treatment includes pharmaceuticals, analgesics, surgery, radiosurgery, low-powered lasers, TENS, acupuncture and biofeedback. Manipulative approaches have been used successfully in a medical center in China, and reports of successful treatment with chiropractic techniques have been published. The patient in this report had a history of right-sided facial pain, diagnosed as trigeminal neuralgia, over a 6-year period with remissions after dental or medical treatment and exacerbations, the most recent of 2 months duration. Prior to cranial and other chiropractic adjustments, the patient had continuous pain that she rated at 9.5 on the visual analogue scale, and after 4 consultations over an 11-day period, pain had reduced to 0.5. Spinal and cranial adjusting potentially affects a wide range of causes of trigeminal neuralgia and offers a conservative, low-cost, low technology initial approach which, if ineffective, will not greatly delay or inhibit other treatment. Occasional maintenance care may be required in some instances to reduce occurrences.

Parallel comparison of grip strength measures obtained with a MicroFET 4 and a Jamar dynamometer, Bohannon RW.

-- Department of Physical Therapy, School of Allied Health, U-2101, University of Connecticut, Storrs, CT 06269-2101, USA.

Percept Mot Skills. 2005 Jun;100(3 Pt 1):795-8.

Abstract: Repeated measures of grip strength obtained bilaterally with a Jamar and a MicroFET 4 dynamometer were compared. Measurements obtained with the MicroFET 4 tended to be slightly (2.2-3.1 lb.) higher but were highly correlated (r > or = .96) with those obtained with the Jamar. Parallel reliability for the two devices was excellent (intraclass correlation coefficient > or = .96). Although clinicians should be cautious about using the devices interchangeably, the MicroFET 4 appears to be a legitimate alternative to the Jamar dynamometer.

Quantifying shoulder rotation weakness in patients with shoulder impingement, Tyler TF, Nahow RC, Nicholas SJ, McHugh MP .

-- Nicholas Institute of Sports Medicine and Athletic Trauma, Lenox Hill Hospital, New York, NY, USA; PRO Sports Physical Therapy of Westchester, New York, NY, USA.

J Shoulder Elbow Surg . 2005 Nov-Dec;14(6):570-4.

Abstract: The purpose of this study was to determine whether strength deficits could be detected in individuals with and without shoulder impingement, all of whom had normal shoulder strength bilaterally according to grading of manual muscle testing. Strength of the internal rotators and external rotators was tested isokinetically at 60 degrees /s and 180 degrees /s, as well as manually with a handheld dynamometer (HHD) in 17 patients and 22 control subjects. Testing was performed with the shoulder positioned in the scapular plane and in 90 degrees of shoulder abduction with 90 degrees of elbow flexion (90-90). The peak torque was determined for each movement. The strength deficit between the involved and uninvolved arms (patients) and the dominant and nondominant arms (control subjects) was calculated for each subject. Comparisons were made for the scapular-plane and 90-90 positions between isokinetic and HHD testing. Despite a normal muscle grade, patients had marked weakness (28% deficit, P < .01) in external rotators at the 90-90 position tested with the HHD. In contrast, external rotator weakness was not evident with isokinetic testing at the 90-90 position (60 degrees /s and 180 degrees /s, 0% deficit, P = .99). In control subjects, greater internal rotator strength in the dominant compared with the nondominant arm was evident with the HHD at the 90-90 position (11%, P < .01) and in the scapular plane (7%, P < .05). Using an HHD while performing manual muscle testing can quantify shoulder strength deficits that may not be apparent with isokinetic testing. By using an HHD during shoulder testing, clinicians can identify weakness that may have been presumed normal

Treatment of an Infant with Wry Neck Associated with Birth Trauma: Case Report, Pederick, F.

Chiro J Aust, 2004; 34:123-8.

ABSTRACT : This paper describes the successful treatment of an infant with wry neck associated with birth trauma using low-force, relatively long-duration cranial adjusting, and soft-tissue techniques to the whole body with special attention to the cervical region, and parental management of home care procedures. Wry neck, or congenital muscular torticollis (CMT), has been a well-recognized condition for centuries. CMT is often associated with plagiocephaly, which has long-term adverse effects on physical and mental functions. A review of some of the literature relating to this condition is provided.

Hypothyroidism: A New Model for Conservative Management in Two Cases, Bablis, P. and Pollard, H.

Chiro J Aust, 2004; 34:11-18

Objective: To review the function, anatomy, physiology, development, hormone synthesis and dysfunction of the thyroid gland. Treatment options are discussed, and 2 case studies of a mind-body therapy (Neuro-Emotional Technique--NET) successfully managing hypothyroid dysfunction are presented. Data Sources: MEDLINE search using key words: thyroid, synthesis, development, anatomy, physiology, hyperthyroidism and hypothyroidism. Data Selection: Eighty-five papers fit the key words and were selected based on relevance to the topic. Papers were selected that contained relevant information on normal and abnormal thyroid function and its management. Data Extraction: Selected papers had to contain information that directly related to the diagnosis, anatomy, physiology and management of hypothyroid conditions. Papers were also selected that described a possible neurophysiological mechanism for the observed treatment effects. Data Synthesis: Objective measures of a new mind-body approach to hypothyroid dysfunction are presented, and its relevance to the biopsychosocial model is discussed. This new treatment is compared to the existing biomedical approaches to treatment. Conclusion: Thyroid dysfunction has been effectively treated with medicine for many years. This paper presents a new therapy that produced objective pre-post changes to hypothyroid dysfunction in 2 cases. This therapy may have potential in future circumstances, with further research recommended to confirm its reliability/validity.

Reliability of hand-held dynamometry in assessment of knee extensor strength after hip fracture, Roy, MA, Doherty, TJ.

-- School of Kinesiology, University of Western Ontario, London, Ontario, Canada.

Am J Phys Med Rehabil. 2004 Nov;83(11):813-8.

OBJECTIVES: To examine the reliability of hand-held dynamometry in assessing knee extensor strength in inpatients undergoing rehabilitation after hip fracture and to examine the discriminant validity of this measure.   DESIGN: A total of 16 subjects (14 women; mean +/- SD, 79 +/- 7 yrs) undergoing inpatient rehabilitation after hip fracture volunteered to participate. Isometric knee extensor strength of the fractured and unfractured sides was determined with a hand-held dynamometer. Subjects were retested 1-2 days after the initial testing session.   RESULTS: Test-retest intraclass correlation coefficients were high for both the fractured (0.91) and unfractured legs (0.90). A low coefficient of variation was observed for both the fractured (15.3%) and unfractured (14.7%) sides. The maximal knee extensor strength was significantly different when comparing the fractured (7.9 +/- 3 kg) and unfractured (15.6 +/- 4 kg) legs. When comparing test 1 and test 2 mean values for the fractured leg, the scores significantly differed (t = 3.14, P < 0.01), with 13 of 16 subjects scoring higher on test 2.   CONCLUSIONS: Hand-held dynamometry is a reliable and valid tool for assessment of knee extensor strength after hip fracture. Reduced knee extensor strength in the fractured leg may be an important component limiting rehabilitation progress in these patients.

Neck muscle fatigue affects postural control in man, Schieppati M, Nardone A, and Schmid M.

Neuroscience, 2003;121(2):277-285.

Central motor excitability changes after spinal manipulation: A transcranial magnetic stimulation study, Dishman J, Ball K, Burke J.

J Manipulative Physiol Ther 2002;25:1-9

Background: The physiologic mechanism by which spinal manipulation may reduce pain and muscular spasm is not fully understood. One such mechanistic theory proposed is that spinal manipulation may intervene in the cycle of pain and spasm by affecting the resting excitability of the motoneuron pool in the spinal cord. Previous data from our laboratory indicate that spinal manipulation leads to attenuation of the excitability of the motor neuron pool when assessed by means of peripheral nerve Ia-afferent stimulation (Hoffmann reflex). Objective: The purpose of this study was to determine the effects of lumbar spinal manipulation on the excitability of the motor neuron pool as assessed by means of transcranial magnetic stimulation. Methods: Motor-evoked potentials were recorded subsequent to transcranial magnetic stimulation. The motor-evoked potential peak-to-peak amplitudes in the right gastrocnemius muscle of healthy volunteers (n = 24) were measured before and after homolateral L5-S1 spinal manipulation (experimental group) or side-posture positioning with no manipulative thrust applied (control group). Immediately after the group-specific procedure, and again at 5 and 10 minutes after the procedure, 10 motor-evoked potential responses were measured at a rate of 0.05 Hz. An optical tracking system (OptoTRAK, Northern Digital Inc, Waterloo, Canada [<0.10 mm root-mean-square]) was used to monitor the 3-dimensional (3-D) position and orientation of the transcranial magnetic stimulation coil, in real time, for each trial. Results: The amplitudes of the motor-evoked potentials were significantly facilitated from 20 to 60 seconds relative to the pre baseline value after L5-S1 spinal manipulation, without a concomitant change after the positioning (control) procedure. Conclusions: When motor neuron pool excitability is measured directly by central corticospinal activation with transcranial magnetic stimulation techniques, a transient but significant facilitation occurs as a consequence of spinal manipulation. Thus, a basic neurophysiologic response to spinal manipulation is central motor facilitation.

Assessment of isokinetic muscle strength in women who are obese, Hulens M, Vansant G, Lysens R, Claessens AL, Muls E.

-- Department of Rehabilitation Sciences, Faculty of Physical Education and Physiotherapy, Katholieke Universiteit, Leuven, Belgium. maria.hulens@flok.kuleuven.ac.be

J Orthop Sports Phys Ther. 2002 Jul;32(7):347-56. 

STUDY DESIGN: Cross-sectional study of isokinetic trunk and knee muscle strength in women who are obese. OBJECTIVE: To provide reference values, to identify variables that affect peripheral muscle strength, and to provide recommendations for isokinetic testing of trunk and knee muscles in women who are obese and morbidly obese. BACKGROUND: The assessment of peripheral muscle strength is useful for the quantification of possible loss of strength, for exercise prescription, and for the evaluation of the effect of training programs in obese individuals. METHODS AND MEASURES: Isokinetic trunk and leg muscle strength was assessed in 241 women who were obese (18-65 years, body mass index (BMI) > or = 30 kg/m2). Trunk flexion and extension peak torque (PT) was measured using the Cybex TEF dynamometer; trunk rotation (TR) PT was measured using the Cybex TORSO dynamometer; and knee flexion/extension (KFE) PT was measured using the Cybex 350 dynamometer. Body composition was assessed using the bioelectrical impedance method; physical activity was assessed using the Baecke questionnaire; and peak VO2 was assessed using an incremental exercise capacity test on a bicycle ergometer. To identify variables related to muscle strength, Pearson correlations were computed and a stepwise multiple regression analysis was performed. RESULTS: Pearson correlation coefficients of all strength measurements at 60 degrees/s revealed low-to-moderate negative associations with age and positive associations with mass, height, fat free mass (FFM), and peak VO2 (P < 0.05), except for gravity-uncorrected trunk extension strength, which was not related to mass. The sports index of the Baecke questionnaire was associated with TR PT (r = 0.20, P < 0.01) and KFE PT (r = 0.18, P < 0.05). CONCLUSION: The weight of the trunk accounts largely for the measured trunk extensor and flexor strength in women who are obese. Contributing variables of isokinetic trunk flexion and extension strength in women who are obese are age, height, and FFM; whereas sports activities and aerobic fitness are contributing factors for trunk rotational and knee extension strength. Recommendations for measuring isokinetic muscle strength in individuals who are obese are provided.

The reliability of upper- and lower-extremity strength testing in a community survey of older adults, Ottenbacher KJ, Branch LG, Ray L, Gonzales VA, Peek MK, Hinman MR.

-- Division of Rehabilitation Sciences, Sealy Center on Aging, University of Texas Medical Branch, Galveston, TX 77555-1028, USA. kottenbo@utmb.edu

Arch Phys Med Rehabil. 2002 Oct;83(10):1423-7.

OBJECTIVE: To examine the stability (test-retest reliability) of strength measures in older adults obtained by nontherapist lay examiners by using a hand-held portable muscle testing device (Nicholas Manual Muscle Tester). DESIGN: A prospective relational design was used to collect test-retest data for 1 male subject by using 27 lay raters who completed intensive training in manual muscle. SETTING: Data were collected from older Mexican-American adults living in the community. PARTICIPANTS: Twenty-seven lay raters who completed intensive training in manual muscle testing for a field-based assessment and interview of older adults and 63 Mexican-American subjects completing wave 4 of the Hispanic Established Populations for the Epidemiologic Study of the Elderly. INTERVENTIONS: Training involved reviewing a manual describing each testing position followed by approximately 6 hours of instruction and practice supervised by an experienced physical therapist. Lay raters then collected test-retest information on older Mexican-American subjects. MAIN OUTCOME MEASURE: Stability (test-retest) for a portable manual muscle testing device. RESULTS: Intraclass correlation coefficients (ICCs) were computed for the 27 lay raters examining 1 male subject (2 trials) and 12 lay raters assessing 63 older Mexican-American adults (1 practice and 2 trials recorded). The ICC values for the first 27 lay raters ranged from .74 to.96. The ICC values for the latter 12 lay raters ranged from .87 to.98. No differences were found in ICC values between male or female subjects. CONCLUSIONS: Stable and consistent information for upper- and lower-extremity strength was collected from the older adults participating in this study. The results suggest reliable information can be obtained by lay raters using a portable manual muscle testing device if the examiners receive intensive training.

A retrospective study of cranial strain patterns in patients with idiopathic Parkinson's disease, Rivera-Martinez, S., Wells, M., Capobianco, J.

Journal of the American Osteopathic Association, August 2002;102(8):417-422

Abstract: While providing osteopathic manipulative treatment to patients with Parkinson's disease at the clinic of the New York College of Osteopathic Medicine of New York Institute of Technology, physicians noted that these patients may exhibit particular cranial findings as a result of the disease. The purpose of this study was to compare the recorded observations of cranial strain patterns of patients with Parkinson's disease for the detection of common cranial findings. Records of cranial strain patterns from physician-recorded observations of 30 patients with idiopathic Parkinson's disease and 20 age-matched normal controls were compiled. This information was used to determine whether different physicians observed particular strain patterns in greater frequency between Parkinson's patients and controls. Patients with Parkinson's disease had a significantly higher frequency of bilateral occipitoatlantal compression (87% vs. 50%; P < .02) and bilateral occipitomastoid compression (40% vs. 10%; P < .05) compared with normal controls. Over subsequent visits and treatments, the frequency of both strain patterns were reduced significantly (occipitoatlantal compression, P < .01; occipitomastoid compression, P < .05) to levels found in the control group.

Radiographic Evidence of Cranial Bone Mobility, Oleski, S, Smith G, Crow W

Cranio: The Journal of Craniomandibular Practice ; Jan 2002;20(1):34-8

Electromyographic reflex response to mechanical force, manually-assisted spinal manipulative therapy, Colloca, C.J., Keller, T.S.

Spine , 2001;26:1117-24

( http://www.journals.elsevierhealth.com/periodicals/ymmt/medline/record/MDLN.11413422 )

Study Design: Surface electromyographic reflex responses associated with mechanical force, manually assisted (MFMA) spinal manipulative therapy were analyzed in this prospective clinical investigation of 20 consecutive patients with low back pain.

Objectives: To characterize and determine the magnitude of electromyographic reflex responses in human paraspinal muscles during high loading rate mechanical force, manually assisted spinal manipulative therapy of the thoracolumbar spine and sacroiliac joints.   Summary of Background Data: Spinal manipulative therapy has been investigated for its effectiveness in the treatment of patients with low back pain, but its physiologic mechanisms are not well understood. Noteworthy is the fact that spinal manipulative therapy has been demonstrated to produce consistent reflex responses in the back musculature; however, no study has examined the extent of reflex responses in patients with low back pain. Methods: Twenty patients (10 male and 10 female, mean age 43.0 years) underwent standard physical examination on presentation to an outpatient chiropractic clinic. After repeated isometric trunk extension strength tests, short duration (<5 msec), localized posteroanterior manipulative thrusts were delivered to the sacroiliac joints, and L5, L4, L2, T12, and T8 spinous processes and transverse processes. Surface, linear-enveloped electromyographic (sEMG) recordings were obtained from electrodes located bilaterally over the L5 and L3 erector spinae musculature. Force-time and sEMG time histories were recorded simultaneously to quantify the association between spinal manipulative therapy mechanical and electromyographic response. A total of 1600 sEMG recordings were analyzed from 20 spinal manipulative therapy treatments, and comparisons were made between segmental level, segmental contact point (spinous vs. transverse processes), and magnitude of the reflex response (peak-peak [p-p] ratio and relative mean sEMG). Positive sEMG responses were defined as >2.5 p-p baseline sEMG output (>3.5% relative mean sEMG output). SEMG threshold was further assessed for correlation of patient self-reported pain and disability. Results: Consistent, but relatively localized, reflex responses occurred in response to the localized, brief duration MFMA thrusts delivered to the thoracolumbar spine and SI joints. The time to peak tension (sEMG magnitude) ranged from 50 to 200 msec, and the reflex response times ranged from 2 to 4 msec, the latter consistent with intraspinal conduction times. Overall, the 20 treatments produced systematic and significantly different L5 and L3 sEMG responses, particularly for thrusts delivered to the lumbosacral spine. Thrusts applied over the transverse processes produced more positive sEMG responses (25.4%) in comparison with thrusts applied over the spinous processes (20.6%). Left side thrusts and right side thrusts over the transverse processes elicited positive contralateral L5 and L3 sEMG responses. When the data were examined across both treatment level and electrode site (L5 or L3, L or R), 95% of patients showed positive sEMG response to MFMA thrusts. Patients with frequent to constant low back pain symptoms tended to have a more marked sEMG response in comparison with patients with occasional to intermittent low back pain. Conclusions: This is the first study demonstrating neuromuscular reflex responses associated with MFMA spinal manipulative therapy in patients with low back pain. Noteworthy was the finding that such mechanical stimulation of both the paraspinal musculature (transverse processes) and spinous processes produced consistent, generally localized sEMG responses. Identification of neuromuscular characteristics, together with a comprehensive assessment of patient clinical status, may provide for clarification of the significance of spinal manipulative therapy in eliciting putative conservative therapeutic benefits in patients with pain of musculoskeletal origin.

Sensory motor control of the lower back: implications for rehabilitation, Ebenbichler, G, Oddsson, L, Kollmitzer, J, Erim, Z.

Med Sci Sports Exer, 2001;33:1889-98

This paper described a series of studies that have been done investigating the surface electromyography (SEMG) fatigue pattern of the back muscles during submaximal contraction. SEMG changes correlated with erector muscle fatigue, validating the subjective erector muscle endurance tests against the objective SEMG. Given the results of this study, a larger double-blind study of SEMG evaluation compared to manual muscle testing could be done, wherein back muscles strength and endurance time during testing are measured before and after a course of chiropractic care.

Ischemia causes muscle fatigue, Murthy, G, Hargens, A, Lehman, S, Rempel, D.

J Orthop Res, 2001;19:436-440

The purpose of this investigation was to determine whether ischemia, which reduces oxygenation in the extensor carpi radialis (ECR) muscle, causes a reduction in muscle force production. In eight subjects, muscle oxygenation (TO 2 ) of the right ECR was measured noninvasively and continuously using near infrared spectroscopy (NIRS) while muscle twitch force was elicited by transcutaneous electrical stimulation (1 Hz, 0.1 ms). Baseline measurements of blood volume, muscle oxygenation and twitch force were recorded continuously, then a tourniquet on the upper arm was inflated to one of five different pressure levels: 20, 40, 60 mm Hg (randomized order) and diastolic (69 ± 9.8 mm Hg) and systolic (106 ± 12.8 mm Hg) blood pressures. Each pressure level was maintained for 3-5 min, and was followed by a recovery period sufficient to allow measurements to return to baseline. For each respective tourniquet pressure level, mean TO 2 decreased from resting baseline (100% TO 2 ) to 99 ± 1.2% (SEM), 96 ± 1.9%, 93 ± 2.8%, 90 ± 2.5%, and 86 ± 2.7%, and mean twitch force decreased from resting baseline (100% force) to 99 ± 0.7% (SEM), 96 ± 2.7%, 93 ± 3.1%, 88 ± 3.2%, and 86 ± 2.6%. Muscle oxygenation and twitch force at 60 mm Hg tourniquet compression and above were significantly lower ( P <0.05) than baseline value. Reduced twitch force was correlated in a dose-dependent manner with reduced muscle oxygenation ( r =0.78, P <0.001). Although the correlation does not prove causation, the results indicate that ischemia leading to a 7% or greater reduction in muscle oxygenation causes decreased muscle force production in the forearm extensor muscle. Thus, ischemia associated with a modest decline in TO 2 causes muscle fatigue.

Comparison of effects of spinal manipulation and massage on motoneuron excitability, Dishman J, Bulbulian R.

Electromyogr Clin Neurophysiol. 2001;41:97-106

This study demonstrates that spinal manipulation results in a normalization of muscle tone in the body.

Measuring knee extensor muscle strength, Bohannon RW.

-- Department of Physical Therapy, School of Allied Health, University of Connecticut, Storrs 06269-2101, USA.

Am J Phys Med Rehabil. 2001 Jan;80(1):13-8.

OBJECTIVE: To compare manual muscle test with hand-held dynamometer measurements of knee extension strength. A secondary analysis of measurements (n = 256 knees) from 128 acute rehabilitation patients was performed. DESIGN: Knee extensor muscle testing was conducted according to the technique of Hislop and Montgomery; 0 to 5 grades were converted to an expanded 0 to 12 scale. Dynamometry was used to measure the isometric knee extension force with 'gravity eliminated.' RESULTS: Manual muscle test and dynamometer measures were highly correlated (r = 0.768; P < 0.001); the correlation was higher when the quadratic nature of the relationship was taken into account (R = 0.887; P < 0.001). Although the dynamometer forces that were associated with different manual muscle test grades differed overall (F = 67.736; P < 0.001), the forces associated with some of the higher grades did not differ statistically. CONCLUSIONS: These findings reinforce the convergent construct validity of the manual muscle test and dynamometry measurements but challenge the discriminant construct validity of manual muscle testing. An alternative manual muscle testing grading scheme is suggested that provides for discriminant validity and retains convergent validity.

The cytological implications of primary respiration, Crisera, P.

Medical Hypotheses , Jan 2001; 56(1):40-51

Abstract : Observing the macroscopic complexities of evolved species, the exceptional
continuity that occurs among different cells, tissues and organs to respond
coherently to the proper set of stimuli as a function of self/species
survival is appreciable. Accordingly, it alludes to a central rhythm that
resonates throughout the cell; nominated here as primary respiration (PR),
which is capable of binding and synchronizing a diversity of physiological
processes into a functional biological unity. Phylogenetically, it was
conserved as an indispensable element in the makeup of the subkingdom
Metazoan, since these species require a high degree of coordination among the different cells that form their body. However, it does not preclude the possibility of a basal rhythm to orchestrate the intricacies of cellular dynamics of both prokaryotic and eukaryotic cells. In all probability, PR emerges within the crucial organelles, with special emphasis on the DNA, and propagated and transduced within the infrastructure of the cytoskeleton as wave harmonics. Collectively, this equivalent vibration for the subphylum Vertebrata emanates as craniosacral respiration (CSR), though its expression is more elaborate depending on the development of the CNS. Furthermore, the author suggests that the phenomenon of PR or CSR be intimately associated to the basic rest/activity cycle (BRAC), generated by concentrically localized neurons that possess auto-oscillatory properties and assembled into a vital network. Historically, during Protochordate-Vertebrate transition, this area circumscribes an archaic region of the brain in which many vital biological rhythms have their source, called hindbrain rhombomeres. Bass and Baker propose that
pattern-generating circuits of more recent innovations, such as vocal, electromotor, extensor muscle tonicity, locomotion and the extraocular system, have their origin from the same Hox gene-specified compartments of the embryonic hindbrain (rhombomeres 7 and 8) that produce rhythmically active cardiac and thoracic respiratory circuits. Here, it implies that PR could have been the first essential biological cadence that arose with the earliest form of life, and has undergone a phylogenetic ascent to produce an integrated multirhythmic organism of today. Finally, in its full manifestation, the breathing DNA of the zygote could project itself throughout the cytoskeleton and modify the electromechanical properties of the plasma lamella, establishing the primordial axial-voltage gradients for the physiological control of development

Attachments from the Spinal Dura to the Ligamentum Nuchae: Incidence, MRI Appearance, and Strength of Attachment, Kenin S, Humphreys BK, Hubbard B, Cramer GD

Proceedings of the 2000 International Conference of Spinal Manipulation   2000;Sept:202-4

Abstract: The identification of attachments to the posterior spinal dura from the surrounding tissues in the cranio-cervical region by Von Lanz in 1929, may provide the key towards a better understanding of underlying mechanisms involved in chronic benign headaches as well as neck pain of unknown etiology.   The recent findings of connective tissue attachments to the cervical spinal dura from muscles, ligament, and osseous elements have sparked increasing interest among clinicians and anatomists.   However, studies of a large number of specimens or those evaluating the MRI appearance of these attachments have never been published.   This study evaluated these attachments in 30 cadaveric spines and then correlated the MRI appearance of the attachments to their anatomic appearance on 4 of the specimens.

This study identified a consistent connective tissue complex arising from within the substance of the ligamentum nuchae, between the occiput and axis, giving rise to 3 connective tissue bridges.   Two of the connective tissue bridges attached to the posterior spinal dura while the third linked the rectus capitis posterior minor muscle to the ligamentum nuchae.   Of significance were: (1) The attachment between the ligamentum nuchae and dura between C1-C2 are quite robust.   (2) The attachments between the rectus capitis posterior minor and ligamentum nuchae usually exist.   (3) The attachments between the ligamentum nuchae and dura mater can be identified on MRI scans.   These attachments may have clinical significance in cervicogenic headache, vertigo, and flexion-extension (whiplash) injuries, making their MRI appearance clinically important.

Conservative lower back treatment reduces inhibition in knee-extensor muscles: a randomized controlled trial, Suter, E., McMorland, G., Herzog, W., Bray, R.

J Manipulative Physiol Ther, 2000;23:76-80

( http://www.journals.elsevierhealth.com/periodicals/ymmt/article/PIIS016147540090071X/abstract )

Background: Knee-joint pathologies, such as anterior knee pain (AKP), are associated with strength deficits and reduced activation of the knee extensors, which is referred to as muscle inhibition (MI). MI is thought to prevent full functional recovery, and treatment modalities that help to reduce or eliminate MI appear necessary for successful rehabilitation. Clinical observations suggest that AKP is typically associated with sacroiliac (SI) joint dysfunction. It is unknown whether Sl-joint dysfunction contributes to knee-extensor deficits and whether correction of SI-joint dysfunction alleviates MI. Objective: The objective of this study was to assess whether conservative low back treatment reduces lower limb MI. Study design: In a randomized, controlled, double-blind study the effects of conservative lower back treatment on knee-extensor strength and MI were evaluated in patients with AKP. Methods: Twenty-eight patients with AKP were randomly assigned to either a treatment or a control group. After a lower back functional assessment, the treatment group received a conservative treatment in the form of a chiropractic spinal manipulation aimed at correcting SI-joint dysfunction. The control group underwent a lower back functional assessment but received no joint manipulation. Before and after the manipulation or the lower back functional assessment, knee-extensor moments, MI, and muscle activation during full effort, isometric knee extensions were measured. Results: Patients showed substantial MI in both legs. Functional assessment revealed SI-joint dysfunction in all subjects (23 symptomatic and 5 asymptomatic). After the SI-joint manipulation, a significant decrease in MI of 7.5% was observed in the involved legs of the treatment group. MI did not change in the contralateral legs of the treatment group or the involved and contralateral legs of the control group. There were no statistically significant changes in knee-extensor moments and muscle activation in either group. Conclusions: The results of this study suggest that SI-joint manipulation reduces knee-extensor MI. Spinal manipulation may possibly be an effective treatment of MI in the lower limb musculature .

Reflex effects of subluxation: the autonomic nervous system, Budgell, B.S.

J Manipulative Physiol Ther, 2000;23(2):104-106

( http://www.journals.elsevierhealth.com/periodicals/ymmt/article/PIIS0161475400900769/abstract )

Background: The collective experience of the chiropractic profession is that aberrant stimulation at a particular level of the spine may elicit a segmentally organized response, which may manifest itself in dysfunction within organs receiving autonomic innervation at that level. This experience is at odds with classic views of neuroscientists about the potential for somatic stimulation of spinal structures to affect visceral function. Objective: To review recent findings from basic physiologic research about the effects of somatic stimulation of spinal structures on autonomic nervous system activity and the function of dependent organs. Data source: Findings were drawn from a major recent review of the literature on the influences of somatic stimulation on autonomic function and from recent original physiologic studies concerning somatoautonomic and spinovisceral reflexes.

Conclusions: Recent neuroscience research supports a neurophysiologic rationale for the concept that aberrant stimulation of spinal or paraspinal structures may lead to segmentally organized reflex responses of the autonomic nervous system, which in turn may alter visceral function.

Abnormalities of the soleus H-reflex in lumbar spondylolisthesis: a possible early sign of bilateral S1 root dysfunction, Mazzocchio R, Scarfo GB, Cartolari R, Bolognini A, Mariottini A, Muzii VF, Palma L.

J Spinal Disord. 2000 Dec;13(6):487-95.

Abstract: Using routine electrodiagnostic procedures, the authors searched for physiologic evidence of nerve root compromise in patients with chronic mechanical perturbation to the lumbar spine. They examined 37 patients with spondylolisthesis and various degrees of degenerative changes in the lumbar canal. Clinical and neurophysiologic findings were compared with data obtained from 36 healthy persons. The soleus H-reflex appeared to be a sensitive indicator of sensory fiber compromise at the S1 root level, because changes correlated well with the focal sensory signs and preceded clinical and electromyographic signs of motor root involvement. When these occurred, the clinical findings were consistent with a more severe nerve root deficit and with radiographic evidence of neural compression. The greater sensitivity of the soleus H-reflex may be related to the pathophysiologic events that occur at the lesion site.

EMG and strength correlates of selected shoulder muscles during rotations of the glenohumeral joint, David G, Magarey ME, Jones MA, Dvir Z, Turker KS, Sharpe M.

Clin Biomech (Bristol, Avon). 2000 Feb;15(2):95-102.

OBJECTIVE: To identify activation patterns of several muscles acting on the shoulder joint during isokinetic internal and external rotation. DESIGN: Combined EMG and isokinetic strength analysis in healthy subjects. BACKGROUND: EMG studies of the shoulder region revealed intricate muscular activation patterns during elevation of the arm but no parallel studies regarding pure rotations of the joint could be located. METHODS: Fifteen (n=30 shoulders) young, asymptomatic male subjects participated in the study. Strength production during isokinetic concentric and eccentric internal and external rotations at 60 and 180 degrees /s was correlated with the EMG activity of the rotator cuff, biceps, deltoid and pectoralis major. Analysis of the smoothed EMG related to the timing of onset of the signal and to the normalized activity at the angle of the peak moment. Determination of the association between the EMG and the moment was based on strength ratios. RESULTS: Findings indicated that for both types of rotations, the rotator cuff and biceps were active 0.092+/-0.038-0.215+/-0.045 s prior to the initiation of the actual movement and 0.112-0.034 s prior to onset of deltoid and pectoralis major activity. These differences were significant in all of the eight conditions (P<0.05). In terms of the strength ratios, strong association was found between electrical activity and moment production in the subscapularis and infraspinatus (r(2)=0.95 and 0. 72, respectively) at the low and high angular velocities. CONCLUSIONS: Prior to actual rotation of the shoulder joint, normal recruitment of the rotator cuff and biceps is characterized by a non-specific presetting phase which is mainly directed at enhancing the joint 'stiffness' and hence its stability. Once movement is in progress, the EMG patterns of these muscles become movement specific and are correlated with the resultant moment. RELEVANCE: Muscular dysfunction relating to delayed onset activity or altered activation patterns, due to pain, perturbed mechanics or disturbed neural activation have been implicated as concomitant factors in other joint associated pathologies. Through highlighting the role of the rotator cuff in shoulder joint rotations, this study lends further support to the argument that a parallel situation may prevail with respect to shoulder joint dysfunction. This could lead to the development of rehabilitation protocols aimed specifically at redressing such dysfunction.

Muscle force measured using "break" testing with a hand-held myometer in normal subjects aged 20 to 69 years, Phillips BA, Lo SK, Mastaglia FL.

-- Centre for Neuromuscular and Neurological Disorders, University of Western Australia, Australian Neuromuscular Research Institute, Perth.

Arch Phys Med Rehabil. 2000 Oct;81(10):1442-3.

OBJECTIVE: To measure the strength of 17 muscle groups in the upper and lower extremities in a large group of healthy subjects using "break" testing with a hand-held myometer, and to examine the intrasession and intersession reliability of the testing protocol. SUBJECTS AND INSTRUMENTATION: A convenience sample of 20 men and 20 women in each decade of age from 20 to 69 years (n = 200) was tested using a Penny & Giles hand-held myometer. RESULTS: Reliability coefficients were >.85 for both intrasession and intersession reliability, except for the ankle dorsiflexors. Men exerted a significantly greater force than women for all muscle groups. Age, weight, and side of testing were significant predictors of force in the majority of muscle groups. The fifth percentile values, as the lower limit of normal, are reported separately for gender and side of testing for each decade of age. CONCLUSION: Using the testing protocol specified in this study, data from patients with various neuromuscular diseases may be compared with the appropriate gender- and age-matched normal data to accurately identify the presence of weakness.

Hand-held dynamometry reliability in persons with neuropathic weakness,
Kilmer DD, McCrory MA, Wright NC, Rosko RA, Kim HR, Aitkens SG.

-- Department of Physical Medicine and Rehabilitation, School of Medicine, University of California, Davis, USA.

Arch Phys Med Rehabil. 2000 Nov;81(11):1538-9.

OBJECTIVE: To determine test-retest reliability of hand-held dynamometry (HHD) in measuring strength of persons with neuropathic weakness. DESIGN: Intratester and intertester reliability of HHD-measured strength over a 7- to 10-day period. In addition, HHD knee strength was compared with criterion standard of fixed dynamometry (FD). SETTING: Human performance laboratory of a university. PARTICIPANTS: Convenience sample of ambulatory outpatients with Hereditary Motor and Sensory Neuropathy, Type I (HMSN) (n = 10) and able-bodied controls (CTL) (n = 11). MAIN OUTCOME MEASURE: Maximal isometric torque. RESULTS: Intratester intraclass correlation coefficients (ICCs) were high, generally ranging from .82 to .96 for HHD- and FD-measured strength for both HMSN and CTL groups. There were no significant differences between sessions for HHD-measured strength, while FD-measured strength was only significantly different for knee extension (p < .01). Intertester reliability was generally good for both HHD- and FD-measured strength, with ICCs ranging from .72 to .97 for HMSN and CTL groups. Exceptions were knee extensors and ankle dorsiflexors for the CTL group. Knee extensor strength was significantly lower measured by HHD compared with FD (p < .01), but knee flexor strength was similar for the two methods. CONCLUSION: HHD appears to be a reliable method to measure maximal isometric strength in persons with neurogenic weakness, and may be useful to quickly and objectively evaluate strength in the clinical setting.

Decrease in quadriceps inhibition after sacroiliac joint manipulation in patients with anterior knee pain , Suter, E., McMorland, G., Herzog, W., Bray, R.

J Manipulative Physiol Ther, 1999;22:149-153

( http://www.journals.elsevierhealth.com/periodicals/ymmt/article/PIIS0161475499701284/abstract )

Background: Evidence exists that conservative rehabilitation protocols fail to achieve full recovery of muscle strength and function after joint injuries. The lack of success has been attributed to the high amount of muscle inhibition found in patients with pathologic conditions of the knee joint. Clinical evaluation shows that anterior knee pain is typically associated with sacroiliac joint dysfunction, which may contribute to the muscle inhibition observed in this patient group. Objective: To assess whether sacroiliac joint manipulation alters muscle inhibition and strength of the knee extensor muscles in patients with anterior knee pain. Design and Setting: The effects of sacroiliac joint manipulation were evaluated in patients with anterior knee pain. The manipulation consisted of a high-velocity low-amplitude thrust in the side-lying position aimed at correcting sacroiliac joint dysfunction. Before and after the manipulation, torque, muscle inhibition, and muscle activation for the knee extensor muscles were measured during isometric contractions using a Cybex dynamometer, muscle stimulation, and electromyography, respectively. Participants: Eighteen patients (mean age, 30.5 ± 13.0 years) with either unilateral ( n = 14) or bilateral ( n = 4) anterior knee pain. Results: Patients showed substantial muscle inhibition in the involved and the contralateral legs as estimated by the interpolated twitch technique. After the manipulation, a decrease in muscle inhibition and increases in knee extensor torques and muscle activation were observed, particularly in the involved leg. In patients with bilateral anterior knee pain, muscle inhibition was decreased in both legs after sacroiliac joint adjustment. Conclusions: Spinal manipulation might offer an interesting alternative treatment for patients with anterior knee pain and muscle inhibition. Because this clinical outcome study was of descriptive nature rather than a controlled design, biases might have occurred. Thus the results have to be verified in a randomized, controlled, double-blinded trial before firm conclusions can be drawn or recommendations can be made.

Electromyographic responses of back and limb muscles associated with spinal manipulative therapy, Herzog, W., Scheele, D., Conway, P.J.

Spine , 1999;24:146-152

( http://www.spinejournal.com/pt/re/spine/abstract.00007632-199901150-00012.htm )

Study Design: Ten young, asymptomatic male subjects underwent 11 clinically relevant spinal manipulative treatments along the length of the spine to test the magnitude and extent of reflex responses associated with the treatments. Objectives: To determine the magnitude and extent of reflex responses elicited by spinal manipulative treatments.

Summary of Background Data: Spinal manipulative treatments have been associated with a reflexogenic relief of pain and a loss of hypertonicity in muscles within the treatment area. However, there is no study in which results show the probability of occurrence or the extent of reflex responses during spinal manipulative treatments. Methods: Asymptomatic subjects received spinal manipulative treatments on the cervical, thoracic, and lumbar levels and on the sacroiliac joint. Reflex activities were measured using 16 pairs of bipolar surface electrodes placed on the back and proximal limb musculature. The percentage of occurrence and the extent of reflex responses in the back and proximal limb musculature were determined. Results: Each treatment produced consistent reflex responses in a target-specific area. The reflex responses occurred within 50-200 msec after the onset of the treatment thrust and lasted for approximately 100-400 msec. The responses were probably of multireceptor origin and were elicited asynchronously. Conclusions: This is the first study in which results show a consistent reflex response associated with spinal manipulative treatments. Because reflex pathways are evoked systematically during spinal manipulative treatment, there is a distinct possibility that these responses may cause some of the clinically observed beneficial effects, such as a reduction in pain and a decrease in hypertonicity of muscles.

Sacroiliac joint involvement in activation of the porcine spinal and gluteal musculature, Indahl, A., Kaigle, A., Reikeras, O., Holm, S.H.

J Spinal Disord, 1999;12:325-30

This experiment involved stimulation of the sacroiliac joint that was found to cause neuromuscular responses in the gluteus maximus, quadratus lumborum, and multifidus muscles. This muscular activation was found to assist in the control of locomotion and body posture and to provide stability to the sacroiliac joint and lumbar spine. Thus, sensitization of sacroiliac joint nociceptive afferents were suggested to not only contribute to mechanical low back pain, but plays a role also in sacroiliac joint biomechanics via reflexogenic activation of the trunk and gluteal muscles. Given the results of this study, a larger double-blind study evaluating sacroiliac joint biomechanics in relationship applied kinesiology diagnostic procedures for the sacroiliac joint could be done, wherein back muscles strength tests are measured before and after a course of chiropractic care for the sacroiliac joints.

Sensorimotor control of the spine, Holm, S., Indahl, A., Solomonow, M.  

Journal of Electromyography and Kinesiology, 1999 12;3:219-234.

( http://www.isek-online.org/ )

EMG recordings of abdominal and back muscles in various standing postures: validation of a biomechanical model on sacroiliac joint stability , Snijders, C.J., Ribbers, M.T., de Bakker, H.V., Stoeckart, R., Stam, H.J.

J Electromyogr Kinesiol, 1998;8:205-14

The Anatomical Basis for the Effectiveness of Chiropractic Spinal Manipulation in Treating Headache, Hack G

The Role of the Chiropractic Adjustment in the Care and Treatment of 332 Children with Otitis Media, Fallon, J.

Journal of Clinical Chiropractic Pediatrics , 1997 Oct; 2(2) :167-83

Objective: To conduct a pilot study of chiropractic adjustive care on children with otitis media using tympanography as an objectifying measure, and to propose possible mechanisms whereby subluxation is implicated in the pathophysiology of otitis media. Design: Case series Setting: Subjects presented in a private clinical practice in New Rochelle, New York. The subjects were referred by various sources including pediatricians, other MDs, chiropractors and parents. Participants: 332 children who presented consecutively with previously diagnosed otitis media, ages 27 days to 5 years. Main Outcome Measures: A survey of the parent/guardian was used to determine historical data with respect to previous otitis media bouts, age of onset of initial otitis media, feeding history, history of antimicrobial therapy, referral patterns, and birth history. Otoscopic and tympanographic data was collected as well as data concerning the number of adjustments administered to produce resolution of the otitis media. Data with respect to recurrence rates over six months was also collected. Results: The average number of adjustments administered by types of otitis media were as follows: acute otitis media (n=127) 4.0±1.03, chronic/serous otitis media (n=104) 5.1±1.53, for the mixed type of bilateral otitis media (n=10) 5.3±1.35 and where no otitis was initially detected on otoscopic and tympanographic exam (but with history of multiple bouts) (n=74) 5.88±1.87. The number of days it took to normalize the otoscopic examination was for acute 6.67±1.9 chronic/serous 8.57±1.96, and 10.18±3.39, and mixed 10.9±2.02. The overall recurrence rate over a six month period from initial presentation in the office was for acute 11.02%, chronic/serous 16.34%, for mixed 30% and for none present 17.56%. Conclusion: To our knowledge this is the first time that tympanography has been used as an objectifying tool with respect to the efficacy of the chiropractic adjustment in the treatment of children with otitis media. As tympanography has been used extensively in the medical assessment of children with otitis media, it also serves as a bridge from which the chiropractic field and the medical field can begin to communicate with respect to otitis media. The results indicate that there is a strong correlation between the chiropractic adjustment and the resolution of otitis media for the children in this study. Normal cranial molding, which is essential for the proper juxtaposition of the cranial bones, often does not occur in the case of a birth malposition, as well as in the case of the child born with the aid of a C- section. This pilot study can now serve as a starting point from which the chiropractic profession can begin to examine its role in the treatment of children with otitis media. Large-scale clinical trials need to be undertaken in the field using tympanography as an objectifying measure. In addition, the role of the occipital adjustment needs to be examined. This study begins the process of examining the role of the vertebral cranial subluxation complex in the pathogenesis of otitis media, and the efficacy of the chiropractic adjustment in its resolution.

A Kaminski-type evaluation of cranial adjusting, Pederick F.O.   

Chiropractic Technique , 1997;9(1):1-15.

Abstract: Models for the evaluation of chiropractic methods have been proposed in the past. This paper uses one model as a framework for the evaluation of cranial adjusting. Chiropractors and osteopaths have been involved in the cranial field for almost 70 years. Over this time, a body of literature has been amassed on clinical experience and research. This article defines and describes one type of cranial adjusting technique and develops a hypothetical model of effects influencing cranial motion. It also discusses measurable observation, particularly in relation to cranial bone motion, and reviews the available literature about experimentation and testing of the technique. Although further experimentation and clinical trials are needed, the type of cranial adjusting technique described has a sound scientific basis as mainstream chiropractic techniques and should receive provisional acceptance within the chiropractic and other professions as an integral part of the chiropractic armamentarium.

Reduced muscle function in patients with osteoarthritis, Fisher NM, Pendergast DR.

-- Department of Rehabilitation Medicine, State University of New York at Buffalo, USA.

Scand J Rehabil Med .1997 Dec;29(4):213-21

Abstract: The purpose of this study was to determine whether subjects with knee osteoarthritis (OA) had reduced muscle strength at various muscle lengths, endurance, contraction velocity and functional capacity, compared with control subjects and whether the decrease was related to functional capacity. Forty-five men and 45 women with knee OA were compared with a control group (41 males, 63 females) of similar age for functional capacity, maximal isometric strength (in vivo length-tension relationship) and endurance (in vivo force-time relationship) of knee flexion and extension and maximal angular velocity (in vivo force-velocity relationship) of knee extension. The OA subjects had increased difficulty (2.03 +/- 0.53) and pain (1.65 +/- 0.29) for activities of daily living (ADLs) and significantly lower strength for extension (72%) and flexion (56%), endurance for the quadriceps (203%) and hamstrings (214%) and velocity (128%). The reductions were greater at longer muscle lengths. These data demonstrate that patients with knee OA have reduced muscle function and functional capacity compared to controls.

Muscle function and gait in patients with knee osteoarthritis before and after muscle rehabilitation, Fisher NM, White SC, Smolinski RJ, Pendergast DR.

Disabil and Rehabil. 1997 Feb;19(2):47-55

Abstract: Patients with knee osteoarthritis (OA) have reduced functional capacity and muscle function that improves significantly after quantitative progressive exercise rehabilitation (QPER). The effects of these changes on the biomechanics of walking have not been quantified. Our goal was to quantify the effects of knee OA on gait before and after QPER. Bilateral kinematic and kinetic analyses were performed using a standard link-segment analysis on seven women (60.9 +/- 9.4 years) with knee OA. All functional capacity, muscle function and gait variables were initially reduced compared to age-matched controls. Muscle strength, endurance and contraction speed were significantly improved (55%, 42% and 34%, respectively) after 2 months of QPER (p < 0.05), as were function (13%), walking time (21%), difficulty (33%) and pain (13%). There were no significant changes in the gait variables after QPER. To use the QPER improvements to the best advantage, gait retraining may be necessary to "re-programme' the locomotor pattern.

Spinal manipulation results in immediate H-reflex changes in patients with unilateral disc herniations, Floman Y, Liram N, Gilai AN.

Eur Spine J. 1997;6(6):398-401.

Abstract: The aim of this clinical investigation was to determine whether the abnormal H-reflex complex present in patients with S1 nerve root compression due to lumbosacral disc herniation is improved by single-session lumbar manipulation. Twenty-four patients with unilateral disc herniation at the L5-S1 level underwent spinal H-reflex electro-physiological evaluation. This was carried out before and after single-session lumbar manipulation in the side-lying position. Eligibility criteria for inclusion in the study were: predominant sciatica, no motor or sphincteric involvement, unilateral disc herniation at the L5-S1 level on CT or MR imaging, age between 20 and 50 years. H-reflex responses were recorded bilaterally from the gastrosoleus muscle following stimulation of tibial sensory fibers in the popliteal fossa. H-reflex amplitude in millivolts (HR-A) and H-reflex latency in milliseconds (HR-L) were measured from the spinal reflex response. Pre- and post-manipulation measurements were compared between the affected side and the healthy side. Statistical evaluation was performed by the Wilcoxon matched-pairs test (SPSS). Thirteen patients displayed abnormal H-reflex parameters prior to lumbar manipulation, indicating an S1 nerve root lesion. The mean amplitude was found to be significantly lower on the side of disc herniation than on the normal, healthy side (P = 0.0037). Following manipulation, the abnormal HR-A increased significantly on the affected side while the normal HR-A on the healthy side remained unchanged (P = 0.0045). There was a significant difference between latencies on the affected side and those on the healthy side (P = 0.003). Following manipulation there was a trend toward decreased HR-L. However, this trend did not reach statistical significance (P = 0.3877). Eight patients displayed no H-reflex abnormalities before or after manipulation. Their respective HR-A and HR-L values did not change significantly following manipulation. Three additional patients were excluded due to technical difficulties in achieving manipulation or measuring spinal reflex. These observations may lend physiological support for the clinical effects of manipulative therapy in patients with degenerative disc disease.

The manual muscle examination for rotator cuff strength. An electromyographic investigation, Kelly BT, Kadrmas WR, Speer KP.

Am J Sports Med. 1996 Sep-Oct;24(5):581-8.

Abstract: The electromyographic activity of eight muscles of the rotator cuff and shoulder girdle (supraspinatus, infraspinatus, subscapularis, pectoralis, latissimus dorsi, and the anterior, middle, and posterior deltoid) was measured from the nondominant shoulders of 11 subjects during a series of 29 isometric contractions. The contractions simulated different positions used for strength testing of the rotator cuff and involved elevation, external rotation, and internal rotation at three degrees of initial humeral rotation (-45 degrees of internal rotation, 0 degree, +45 degrees of external rotation) and scapular elevation (0 degree, 45 degrees, 90 degrees). Isolation of the supraspinatus muscle was best achieved with the test position of elevation at 90 degrees of scapular elevation and +45 degrees (external rotation) of humeral rotation. Isolation of the infraspinatus muscle was best achieved with external rotation at 0 degree of scapular elevation and -45 degrees (internal rotation) of humeral rotation. Isolation of the subscapularis muscle was best achieved with the Gerber push-off test. This study used four criteria for identifying the optimal manual muscle test for each rotator cuff muscle: 1) maximal activation of the cuff muscle, 2) minimal contribution from involved shoulder synergists, 3) minimal provocation of pain, and 4) good test-retest reliability. Based on the results of this study and known painful arcs of motion, an objective identification of the optimal tests for the manual muscle testing of the cuff was elucidated.

Kinematic system demonstrates cranial bone movement about the cranial sutures, Lewandoski, MA, Drasby, E, Morgan, M, Zanakis, M

  J Am Osteopath Assoc , 1996;96(9):551.

( http://www.jaoa.org )

Disturbed eye movements after whiplash due to injuries to the posture control system, Gimse R, Tjell C, Bjorgen IA, Saunte C.  

J Clin Exp Neurophychol, 1996;18(2):178-86.

Normative values for isometric muscle force measurements obtained with hand-held dynamometers, Andrews AW, Thomas MW, Bohannon RW.

-- University of North Carolina Hospitals, Chapel Hill, 27514, USA.

Phys Ther. 1996 Mar;76(3):248-59. 

BACKGROUND AND PURPOSE: The extent of a patient's impairment can be established by comparing measurements of that patient's performance with normative values obtained from apparently unimpaired individuals. Only a few studies have described normative values for muscle strength measured by hand-held dynamometry. The purpose of this study of older adults, therefore, was to obtain normative values of maximum voluntary isometric force using hand-held dynamometers. SUBJECTS: One hundred fifty-six asymptomatic adults (77 men, 70 women) participated in this study. The subjects' mean age was 64.4 years (SD=8.3, range=50-79). The male subjects' mean age was 64.5 years (SD=8.4, range=50-79), and the female subjects' mean age was 64.3 years (SD=8.2, range=50-79). METHODS: Gender, age, dominant side, height, weight, and activity level were recorded. Eight upper-extremity movements (shoulder flexion, extension, abduction, and medial and lateral rotation; elbow flexion and extension; and wrist extension) and five lower-extremity movements (hip flexion and abduction, knee flexion and extension, and ankle dorsiflexion) were resisted by one of three experienced testers using a strain-gauge hand-held dynamometer. RESULTS: Gender, age, and weight were identified as independent predictors of force for all muscle actions on both the dominant and nondominant sides. These variables were used, therefore, to create regression equations and normative values for the force of each muscle action. CONCLUSION AND DISCUSSION: The reference values provided may allow clinicians who follow the described testing protocol to estimate the severity of force-generating impairments in patients aged 50 to 79 years.

Sacroiliac joint manipulation decreases the H-reflex, Murphy, B.A., Dawson, N.J., Slack, J.R.

Electromyogr Clin Neurophysiol , 1995;35:87-94

A Preliminary Single Case Magnetic Resonance Imaging Investigation into Maxillary Frontal-Parietal Manipulation and Its Short-Term Effect upon the Intercranial Structures of an Adult Human Brain, Pick, M.

J Manipulative Physiol Ther. 1994;17(3)

Objective : To investigate the hypothesis that external cranial manipulation can cause change within the structures of the human brain. (42 y/o subject). Results: Second MRI showed elimination of a 5-mm peak along the superior border of the corpus collosum and a 4 - mm reduction in the width of the fornix column. The exposed anterior posterior wall of the lateral ventricle posterior to the fornix col. increased 51 degrees cephalad with the application (to the bregma and the maxillary palate). The angular surface of the central lobule altered by minus 7 degrees. The subject experienced no change in his asymptomatic condition as a result of this study. Conclusion: The present study supports the theory that external cranial manipulation affects the structure of the brain. It also suggests support for the theory regarding suture mobility.

The role of sensory information in the guidance of voluntary movement, McCloskey, D.I., Prochazka, A.

Somatosensory and Motor Research , 1994;11:69-76

Abstract: For voluntary movements to be well timed and accurate, they require coordinated tactile, visual and proprioceptive information about the movement in progress. Locomotion should be a stable cycle generated by the sensory links between the musculoskeletal system, the neural system and the environment.

Various Forms of Chiropractic Technique, Bergmann, T.

Chiropractic Technique, May 1993; 5(2):53-5.

Role of cranial bone mobility in cranial compliance, Heisey, SR, Adams, T.

Neurosurgery, 1993;33(5):869-876.

Neuromuscular effects of temporomandibular joint dysfunction, Esposito, V., Leisman, G., Frankenthal, Y.

Intern J Neuroscience, 1993;68

Abstract: Neurologically intact male and female TMJ dysfunction patients with or without cervical spine involvement were examined using standard clinical neurologic testing for balance and coordination. Seventy percent of the TMJ patients without cervical involvement exhibited positive signs for balance, coordination, and/or ataxia found in response to having the patient's mandible stressed by extending it a far as possible laterally, and also opened (as wide as possible) or closed (biting down). The performance of patients with cervical involvement was not significantly different than those without cervical involvement. Further examination of the relation between the TMJ and auditory, visual, cerebellar, and coordination mechanisms is therefore indicated.

The reflex effects of spinal somatic nerve stimulation on viscera function, Sato, A.

J Manipulative Physiol Ther, 1992;15(1):57-61

Abstract: This paper studies somatovisceral reflex responses in the cardiovascular organ, gastrointestinal tract, urinary bladder and adrenal medulla in anesthetized animals after eliminating emotional factors following somatic sensory stimulations. Various somatic sensory stimulations, including cutaneous, muscle and articular sensory stimulations, can produce differing autonomic reflex responses, depending on which visceral organs and somatic afferents are stimulated. Some responses have dominant sympathetic efferent involvement, whereas others have dominant parasympathetic efferent involvement. Some responses have propriospinal and segmental characteristics, while others have supraspinal and generalized characteristics in their reflex nature. These somatovisceral reflex responses may be functioning during spinal manipulative therapy in conscious humans.

Changes in Magnitude of Relative Elongation of the Falx Cerebri During the Application of External Forces on the Frontal Bone of an Embalmed Cadaver, Kostopoulos, D., Keramidas, G.

Journal of Craniomandibular Practice, January 1992.

Evaluation of neck muscle strength with a modified sphygmomanometer dynamometer: reliability and validity, Vernon HT, Aker P, Aramenko M, Battershill D, Alepin A, Penner T.

-- Canadian Memorial Chiropractic College, Toronto, Ontario.

J Manipulative Physiol Ther. 1992 Jul-Aug;15(6):343-9. 

OBJECTIVE : Determine test-retest reliability, normative data and clinical validity of isometric muscle strength testing in the neck with a modified sphygmomanometer dynamometer (MSD). DESIGN: Analytic survey. Paired trials of various muscle strength tests were conducted on convenience samples of normal subjects and consecutive samples of symptomatic subjects. SETTING: Outpatient chiropractic research clinic. PATIENTS/SUBJECTS: For study 2, 40 normal male subjects, average age 25 +/- 2 yr, were studied for reliability and normative data. For study 3, 24 symptomatic patients, 12 males and 12 females, average age 39 +/- 7 yr, were studied, 8 with "whiplash"-type injuries (average duration 22.5 wk) and 16 with nontraumatic chronic neck pain (average duration 110 wk). INTERVENTION: No therapeutic intervention is reported. MAIN OUTCOME MEASURE: Pressure levels generated by subjects against a modified sphygmomanometer-type dynamometer as measured in kilopascals. RESULTS: Study 1. Repeated paired trials of a standardized weight column (20 lbs) produced a coefficient of variation of 0.84% and virtually no difference between the means of the first vs. second trials. Study 2. High test-retest correlation coefficients were found for all ranges of motion (.79-.97). Right-to-left asymmetry in rotation and lateral flexion was within 6-8%. The flexion/extension ratio was .57:1, indicating that in normal subjects, flexion was approximately 40% lower than extension. Lower cutoffs were established as the mean--1 SD as follows (in kPa): flexion--3300, extension--5800, rotation--5200 and lateral flexion--6200. Coefficients of variation ranged from 25 to 29%. Study 3. Differences between paired trials were analyzed by intraclass coefficients, which were very high (.95-.99), and by percentages, which ranged from 4 to 10.4%, with an average of 7%, indicating a high degree of test-retest consistency. The mean values for all symptomatic subjects for flexion, extension, right rotation and right lateral bending were all well below the normal cutoff values as found in study 2. The flexion/extension ratio for whiplash subjects was 0.25:1.00, which is half of that of normal subjects. CONCLUSIONS: The MSD has been found to be a reliable instrument for the evaluation of isometric muscle strength in the neck in normal and symptomatic subjects. Normative values for absolute test levels, bilateral symmetry and flexion/extension ratios have been determined. A symptomatic group demonstrated significant deviations from these norms in the form of reduced strength levels and reduced flexion/extension ratios, while still maintaining very high levels of test-retest consistency and bilateral symmetry. The MSD appears very promising in the evaluation of neck-injured patients.

Postural control in young and elderly adults when stance is perturbed: kinematics, Alexander, N. B, Shepard, N, Gu, MJ, Schultz, A.  

Journal of Gerontology , 1992; 47:M79-M87.

Case Study: The effect of utilizing spinal manipulation and craniosacral therapy as the treatment approach for attention deficit-hyperactivity disorder, Phillips, C.

Proceedings of the National Conference on Chiropractic , 1991 Nov:57-74

ABSTRACT: Due to the subjective nature of this disorder, evaluations and treatment results have considerable limitations and cannot be generalized to the entire population. It is this author's intent to describe an alternative treatment protocol and its effect on one subject. In this particular case, initial chiropractic spinal adjustive care was effective in reducing the frequency of ear infections, allergic reactions, and headaches, but was ineffective at decreasing the severity of ADHD characteristics. Incorporation of craniosacral therapy with spinal adjustive therapy resulted in a positive alteration in the ADHD symptomatology. The teacher's report of improvement in performance skills was significant as teacher ratings have been found to have empirical corroboration of ADD. While conclusions cannot be drawn based on a single case report, it was the opinion of this author that the results justified a more detailed analysis of this treatment protocol for ADD/ADHD. The NWCC Center for Clinical Studies has begun treatment on 17 additional patients with this disorder. If results are similar, a large scale research project will be implemented to investigate further the role that chiropractic spinal and cranial therapy may play in the treatment of Attention Deficit Hyperactivity Disorder.

The pain-adaptation model: a discussion of the relationship between chronic musculoskeletal pain and motor activity, Lund, J.P., et al.  

Canadian Journal of Physiology and Pharmacology, 1991;69:683-694.

Effects of Soft Tissue Technique and Chapman's Neurolymphatic Reflex Stimulation on Respiratory Function, Lines, D., McMillan, A., Spehr, G.

J Aust Chiro Assoc 1990 Mar;20(1):17-22

Limb Segment Information Transmission Capacity Infers Integrity of Spinothalamic Tracts and Cortical Visual-Motor Control, Leisman, G., Vitori, R.

International Journal of Neuroscience . 1990; 50:175-183.

Abstract: Limb segment movement times have been investigated previously in relation to Fitts' Index of Difficulty (ID = log 2 2A/W) over various movement distances. Results supported Fitts' theory that different limb segments show different maximum information processing rates. The results indicated that visually-mediated discrete correction control processes are used. In the presently reported experiments, normal human subjects performed movements with left or right arms. Visual-motor control was inter- or intrahemispheric. Direction of movement was adductive or abductive. It was hypothesized that abductive movements are controlled by the contralateral hemisphere while adductive movements are controlled by either hemisphere. It was also hypothesized that abductive movements are related to the lateral system which projects to the contralateral side of the spinal cord. The control of adductive movements is related to the medial system which projects bilaterally to the spinal cord.

The Relationship Between CSF and Fluid Dynamics in the Neural
Canal, Flanagan, M.

J Manipulative Physiol Ther , Dec 1988;11(6):489-92

Intrarater reliability of manual muscle testing and hand-held dynametric muscle testing, Wadsworth CT, Krishnan R, Sear M, Harrold J, Nielsen DH.

Phys Ther. 1987 Sep;67(9):1342-7. 

Physical therapists require an accurate, reliable method for measuring muscle strength. They often use manual muscle testing or hand-held dynametric muscle testing (DMT), but few studies document the reliability of MMT or compare the reliability of the two types of testing. We designed this study to determine the intrarater reliability of MMT and DMT. A physical therapist performed manual and dynametric strength tests of the same five muscle groups on 11 patients and then repeated the tests two days later. The correlation coefficients were high and significantly different from zero for four muscle groups tested dynametrically and for two muscle groups tested manually. The test-retest reliability coefficients for two muscle groups tested manually could not be calculated because the values between subjects were identical. We concluded that both MMT and DMT are reliable testing methods, given the conditions described in this study. Both testing methods have specific applications and limitations, which we discuss.

Changes in Electrical Activity in Muscles Resulting from Chiropractic Adjustment: A Pilot Study, Shambaugh P.

J Manipulative Physiol Ther 1987;10(6):300-304

This study examines the effects of chiropractic adjustment on the muscles of the back. Vertebrae that are hypomobile may be held in that state by the erector spinae muscle group; adjusting such vertebrae should result in les muscle tension. By measuring the change in electrical activity, such relaxation can be observed. Hypomobile vertebrae were found by motion palpation. The patient was then placed prone and surface electrodes were placed over the upper trapezius, upper erector spinae (T3-T5), and lumbar erector spinae (L1-L3) muscle groups on both sides of the body. The patient was adjusted using full spine toggle recoil thrusts, and postadjustment readings were taken. Results from this study show that significant changes in muscle electrical activity occur as a consequence of adjusting. On average, a 25% reduction in muscle activity was observed across the 20 subjects tested, while no significant reductions were observed with the control group of 14 subjects. Significant reductions in side-to-side imbalances were also observed.

Quantifying the Effects of Spinal Manipulations on Gait, Using Patients with Low Back Pain: A Pilot Study, Herzog W, Nigg B, Robinson R, Read L.

J Manipulative Physiol Ther 1987;10(6):295-299

A pilot study was performed to investigate the effects of chiropractic treatment on the gait of one patient with a chronic sacroiliac joint syndrome. Qualitative and quantitative measures were used to describe pain, sacroiliac joint mobility, functional ability and gait patterns of this patient before and after receiving chiropractic treatment, and throughout the rehabilitation period. For this patient, chiropractic treatment reduced the low back pain and was associated with significant changes in selected gait parameters. A study involving 10-20 subjects is under way to possibly generalize the findings of this investigation.

Finger flexion function in rheumatoid arthritis: the reliability of eight simple tests, Armstrong R, Horrocks A, Rickman S, Heinrich I, Kay A, Gibson T.

Br J Rheumatol 1987;26:118-122.

The inter- and intra-observer errors of eight tests of finger flexion function were estimated from the results obtained by three observers assessing 10 patients with rheumatoid hand involvement. Measurements of finger flexion and muscle power involved both conventional and novel techniques using simple and easily constructed apparatus. For each test, measurements were in agreement between observers and were reproducible on three occasions. These tests may now be used with confidence by other investigators.

Functional assessment of the hand: reproducibility, acceptability, and utility of a new system for measuring strength, Helliwell P, Howe A, Wright V.

Ann Rheum Dis 1987;46:203-208

A new system for measuring strength of the hand using a torsion dynamometer linked to a microprocessor is described. The system permits analysis of timed squeezes of both grip and pinch and is adjustable to all sizes of hand and degrees of hand deformity. Results obtained with the system were found to be reproducible, and the rigid device was acceptable to a group of patients with arthritic hands. In rheumatoid arthritis, there is a marked reduction in maximum grip and pinch strength, together with a prolongation of the time taken to reach this maximum, and increased fatigue. The limitations of grip strength as a measure of function of the hand are discussed.

Clinical and electromyographical course of sciatica: prognostic study of 41 cases, Negrin P, Fardin P.

Electromyogr Clin Neurophysiol 1987;27:125-127

Abstract: The study of the clinical and EMGraphical course of patients with sciatica may help us to decide between a simple symptomatic treatment and an admission to hospital for neuroradiological tests and possible surgery. 41 patients with acute lumbosciatalgia and EMGraphically proven monoradicular denervation were studied: the root affected was L5 in 39 cases (78%), L4 in 7 cases and S1 in 2 cases. 19 of these cases were then submitted to surgical treatment of disc protrusion removal, the other 22 were treated medically. 3 to 8 years later, the following parameters were tested: pain, motor impairment, EMG denervation and degree of patient's subjective judgment. We concluded that urgent hospital admission is indicated only in the case of severe and/or recent (within 1 month) paralysis or in the case of intolerable painful symptomatology. The diagnostic and prognostic role of EMG is hence confirmed: this examination yields information on the identity of the root involved, the severity of the denervation, its course and the degree of final improvement expected.

The use of major and minor therapy forms in
Australian chiropractic practice, Leboeuf, C, Patrick, K.

Journal of the Australian Chiropractic Association , 1987;17:109-11.

A survey of Australian chiropractors showed that most use five major
chiropractic techniques (Diversified, Sacro-Occipital technique, Gonstead,
Nimmo and Applied Kinesiology). High velocity adjustive techniques
(Diversified and Gonstead) were the most commonly reported major core
techniques. Predominantly low velocity manual techniques such as Applied
Kinesiology, Sacro-Occipital technique and Nimmo were most commonly reported as minor core techniques. Most employ adjunctive therapies, mainly nutrition, extremity techniques and exercise.

The relationship of knee and ankle weakness to falls in nursing home residents, Whipple, R, Wolfson, L, Amerman, P.

J Am Geriatr Soc, 1987;35:329-32

A study of nursing home residents with a history of falling found that muscle force and isokinetic power were significantly decreased in knee flexors (quadriceps) and extensors (hamstrings), and ankle dorsiflexors (tibialis anterior) and plantar flexors (gastrocnemius and soleus). Dorsiflexors were particularly weak in fallers, suggesting that they are an important factor contributing to balance. Of particular interest was ankle flexor and extensor strength because these muscles are linked to balance impairment in older adults with a history of falling. Strength training and other treatments that may improve muscle function in these areas may enhance balance in balance-impaired older adults.

Piriformis syndrome: pathogenesis, diagnosis, and treatment, Steiner C, Staubs C, Ganon M, Buhlinger C.

J Am Osteopath Assoc 1987;87:318-323

The failure of conservative treatment for lumbosacral disk disorders often leads to surgery. If the pain is produced by sciatic neuritis rather than sciatic radiculitis, operative treatment may be unavailing. This paper describes the mechanism by which piriformis syndrome causes sciatic neuritis and differentiates neuritis from radiculitis, the treatment of which often results in the "failed disk syndrome." Sciatic neuritis is now believed to result from irritation of the sciatic nerve sheath, which is caused by biochemical agents released from an inflamed piriformis muscle where the two structures meet at the greater sciatic foramen. The symptoms of piriformis syndrome present almost identically to lumbar disk syndrome, except for the consistent absence of true neurologic findings. Diagnosis is accomplished by palpation of myofascial trigger points within the piriformis muscle. Computed tomography, myelography, roentgenography, and electromyography are of limited diagnostic value. Treatment, which consists of a conservative approach employing local anesthetics and osteopathic manipulation, is without significant risk. Reducing muscle spasm, restoring joint motion, and keeping the patient ambulatory and in motion are keys to successful treatment.

Correlation of objective measure of trunk motion and muscle function with low-back disability ratings, Triano, J, Schultz, A

Spine, 1987;12:561-5

Clinical biomechanical correlates for cervical function: Part II. A myoelectric study, Vorro J, Johnston W.

J Am Osteopath Assoc 1987;87:353-367

Part 1 of this study compared cervical motion ranges for two groups of human subjects classified as symmetric or asymmetric on the basis of a single clinical test for cervical sidebending. Data from the asymmetric group revealed limited mobility in all primary rotations and in secondary deviations. Part 2 reports on the concurrent, bilateral measurement of electromyographic activity for 12 selected muscle sites during the movements executed. Data revealed that muscles in the asymmetric group were slower to initiate action and were reduced in time and strength of contraction. Because muscles provide the motive forces for the reduction in range previously reported, these myoelectric data expand understanding of the disturbance in physiologic function that is indicated when a clinical test for response to motion in a spinal region is positive for asymmetry.

Contractile changes in opposing muscles of the human ankle join with aging, Vandervoort, A, McComas, A.

J Appl Physiol, 1986;61:361-7

This article demonstrates that strength declines approximately 15% per decade between the ages of 50 and 70 years, and approximately 1.5% per year after the age of 70 years, and decreases in strength are associated with falling in elderly people.

Manual muscle test scores and dynamometer test scores of knee extension strength, Bohannon RW.

Arch Phys Med Rehabil. 1986 Jun;67(6):390-2. 

The knee extension force of 50 patients was investigated using traditional manual muscle testing and hand-held dynamometry. The relationship between manual muscle test word scores and dynamometer force scores was determined using Kendall tau, as was the relationship between manual muscle test percentage scores and dynamometer scores expressed as a percentage of "normal." Percentage scores were also compared to determine if a significant difference existed. Manual muscle test scores and dynamometer test scores were significantly correlated (p less than .001). Percentage manual muscle test and dynamometer test scores were significantly different (p less than .001). These results suggest that the two procedures measure the same variable-strength. Manual muscle test percentage scores of knee extension may, however, overestimate the extent to which a patient is "normal."

Predictive value of manual muscle testing and gait analysis in normal ankles by dynamic electromyography, Perry, J.P. et al

Foot Ankle. 1986 Apr;6(5):254-9.

Eight muscles about the ankle of seven normal subjects were assessed by electromyography (EMG) during manual muscle testing (MMT) and walking. Three strength levels (normal, fair, trace) and three gait velocities (free, fast, slow) were tested. The muscles studied included the gastrocnemius, soleus, posterior tibialis, flexor digitorum longus, flexor hallucis longus, anterior tibialis, extensor digitorum longus, and extensor hallucis longus. Relative intensity of muscle action was quantitated visually (using an eight-point scale based on amplitude and density of the signal). The data showed that EMG activity increased directly as more muscle force was required during the different manual muscle test levels and increased walking speeds. No MMT isolated activity to the specific muscle though being tested. Instead, there always was a synergistic response. Both the gastrocnemius and soleus contributed significantly to plantarflexion regardless of knee position. The intensity of muscle action during walking related to the manual muscle test grades. Walking at the normal free velocity (meters/min) required fair (grade 3) muscle action. During slow gait the muscle functioned at a poor (grade 2) level. Fast walking necessitated muscle action midway between fair and normal, which was interpreted as good (grade 4).

Biodynamics of the Cranium: A Survey, Blum, C.

The Journal of Craniomandibular Practice, Mar/May 1985:3(2):164-71.

Physical measurements as risk indicators for low back trouble over a one year period, Biering-Sorensen, F.

Spine, 1984;9:106-19

Effects of manipulation on gait muscle activity: preliminary electromyographic research, Hibbard D.

J Am Chiro Assoc 1983;17:49-51

Occlusal Changes Related to Cranial Bone Mobility, Libin, B.

International Journal of Orthodontics , 20(1), March 1982

Detection of skull expansion with increased cranial pressure, Heifitz, MD, Weiss M.  

J Neurosurg, 1981;55:811-812

Electromyographic analysis following chiropractic manipulation of the cervical spine: a model to study manipulation-induced peripheral muscle changes, Rebechini-Zasadny H, Tasharski C, Heinze, W.

J Manipulative Physiol Ther 1981;4:61-63

This study showed the effects of chiropractic manipulation upon the musculature, specifically an increase in finger strength after cervical adjusting.

Usefulness of electrophysiological studies in the diagnosis of lumbosacral root disease, Tonzola R, Ackil A, Shahani B, Young R.

Ann Neurol 1981;9:305-308

This study demonstrates that EMG shows better correlation with neurological examinations than CT scans or myelograms for nerve root disturbances in the lumbosacral spine.

The Application of Neurological Reflexes to the Treatment of Hypertension, Mannino, R.

Journal of the American Osteopathic Association , Dec 1979:225-230

Muscular Strength Correlated to Jaw Posture and the Temporomandibular Joint - Examination of a Professional Football Population , Smith, S.D.

New York State Dental Journal, 44(7);Aug/Sept 1978

Discogenic radiculopathy: use of electromyography in multidisciplinary management, Lane M, Tamhankar M, Demopoulos J.

NY State J Med 1978;78:32-36

This study demonstrated an 85% agreement between EMG evaluation and neurological work-up, evidencing nerve root compromise. There is evidence offered that EMG readings may be equivalent to subluxation determination. This study shows that changes in muscle electrical activity measured in distinct myotomes revealed nerve root disturbance. The study concludes that a positive EMG finding, indicating the presence of a lesion at the level of the root or proximal in the spinal cord, should alert the clinician.

"The Relationship of Craniosacral Examination Findings in Grade School Children with Developmental Problems", Upledger, J.

Journal of the American Osteopathic Association , June 1978; 77: 760/69 - 776/85.

Abstract: A standardized craniosacral examination was conducted on a mixed sample of 203 grade school children. The probabilities calculated supported the existence of a positive relationship between elevated total craniosacral motion restriction scores and the classifications of "not normal," "behavioral problems," and "learning disabled," by school authorities, and of motion coordination problems. There was also a positive relationship between an elevated total craniosac