Assessment, management, and rehabilitation of traumatic peripheral nerve injuries for non-surgeons

Electrodiagnostic evaluation is often requested for persons with peripheral nerve injuries and plays an important role in their diagnosis, prognosis, and management. Peripheral nerve injuries are common and can have devastating effects on patients' physical, psychological, and socioeconomic well-being; alongside surgeons, electrodiagnostic medicine specialists serve a central function in ensuring patients receive optimal treatment for these injuries. Surgical intervention-nerve grafting, nerve transfers, and tendon transfers-often plays a critical role in the management of these injuries and the restoration of patients' function. Increasingly, nerve transfers are becoming the standard of care for some types of peripheral nerve injury due to two significant advantages: first, they shorten the time to reinnervation of denervated muscles; and second, they confer greater specificity in directing motor and sensory axons toward their respective targets. As the indications for, and use of, nerve transfers expand, so too does the role of the electrodiagnostic medicine specialist in establishing or confirming the diagnosis, determining the injury's prognosis, recommending treatment, aiding in surgical planning, and supporting rehabilitation. Having a working knowledge of nerve and/or tendon transfer options allows the electrodiagnostic medicine specialist to not only arrive at the diagnosis and prognosticate, but also to clarify which nerves and/or muscles might be suitable donors, such as confirming whether the branch to supinator could be a nerve transfer donor to restore distal posterior interosseous nerve function. Moreover, post-operative testing can determine if nerve transfer reinnervation is occurring and progress patients' rehabilitation and/or direct surgeons to consider tendon transfers.

Clinimetric evaluation of five clinically feasible measures of the leg extensor muscle strength in neurological rehabilitation settings

A gold-standard clinical measure of leg muscle strength has not been established. Therefore, the aim of this study was to evaluate clinimetric properties of five clinically feasible measures of lower-limb extensor muscle strength in neurological rehabilitation settings. This was a cross-sectional observational study of 36 participants with leg weakness as a result of a neurological condition/injury. Participants were recruited across a range of walking abilities, from non- to independently ambulant. Each was assessed using each of the following five measures: manual muscle test (MMT), hand-held dynamometry (HHD), seated single leg press one repetition maximum (1RM), functional sit-to-stand (STS) test and seated single leg press measured with a load cell. Each clinical measure was evaluated for its discriminative ability, floor/ceiling effects, test-retest reliability and clinical utility. The load cell and HHD were the most discriminative of the tests and were also resistant to floor/ceiling effects; however, the load cell was superior to the HHD when compared for its clinical utility. The MMT/STS tests received perfect scores for clinical utility, although similar to the 1RM test, they were susceptible to floor and ceiling effects. The load cell leg press test was the only measure of lower limb strength to satisfy all four clinimetric properties. Implications for clinical practice include, firstly, that strength tests available to clinicians vary in their clinimetric properties. Secondly, the functional status of the person will determine selection of the best clinical strength test. And lastly, load cell device technology should be considered for clinical strength assessments.

Practice day may be unnecessary prior to testing knee extensor strength in young healthy adults

A practice session is common prior to strength testing. However, the benefits of practice have not been previously reported. The purpose of this study was to determine the effect of a practice session on peak torque, mean torque and between trial variability across three test days. We hypothesized that peak and mean torque would be higher and less variable the second and third test days than the first. Twenty-five healthy, young participants completed 3 maximal voluntary isometric and isokinetic knee extensions on three separate days. No difference in isometric torque was found between days 1 and 2, but there was a significant decrease in isokinetic torque (8.45 Nm). There was a significant decrease in both mean isometric and isokinetic torque from day 1 to day 3 (12.67 and 13.59 Nm). Contrary to our hypothesis, no benefit from a practice session was found. Healthy, young adults are able to produce peak knee extensor torques on the first day of testing and do not demonstrate any benefit from additional testing. Thus, a practice day preceding isometric and isokinetic knee extensor strength testing may not be necessary when testing healthy, young participants, and may, in fact, negatively impact subsequent strength measurements.

Considerations and Practical Options for Measuring Muscle Strength: A Narrative Review

Muscle strength impairments are related to mobility limitations and other untoward outcomes. This narrative review, therefore, describes considerations relative to the definition and measurement of muscle strength. Thereafter, practical options for measuring muscle strength are described and their clinimetric properties are delineated. Information provided herein may help students, clinicians, and researchers select the strength tests best suited to their research needs and limitations.

Whole-Body Vibration Training Designed to Improve Functional Impairments After Pediatric Inpatient Anticancer Therapy: A Pilot Study

PURPOSE

To assess a whole-body vibration (WBV) intervention for children after cancer treatment.

METHODS

Eleven children after inpatient anticancer therapy participated in a 12-week supervised WBV intervention, which consisted of one 9- to 13-minute WBV session per week, with 5 to 9 minutes' overall vibration time. Feasibility was defined as the ability to participate in WBV training without reporting adverse events. The number of offered and completed training sessions, program acceptance, and measures of function were assessed.

RESULTS

Nine participants completed the WBV intervention without any WBV-related adverse events. The adherence rate was 87.96%. Only minor side effects were reported and there was general program acceptance. We found indications that WBV has positive effects on knee extensor strength and active ankle dorsiflexion range of motion.

CONCLUSIONS

WBV was feasible, safe, and well received among children after inpatient anticancer therapy. No health deteriorations were observed. Positive effects need to be confirmed in future trials.

Use of myometry in the assessment of neuropathic weakness: testing for reliability in clinical practice

The myometer has been recommended as a quantitative method of measuring muscle strength in clinical practice. The reliability of the myometer was tested in a clinical environment by physiotherapists and a form incorporating the testing positions was designed. An intensive training programme for examiners was instigated and piloted on normal subjects. The study tested the reliability of paired examiners in recording the muscle strength of 20 Guillain-Barre syndrome patients at different stages in their recovery. Ten patients were tested in the first experiment. The error rate between observers was large and unacceptable. Procedures for improving reliability were implemented. Testing was repeated on 10 more patients but no improvement in reliability was observed. The implications for clinical practice are discussed.

Reliability of maximal isometric knee strength testing with modified hand-held dynamometry in patients awaiting total knee arthroplasty: useful in research and individual patient settings? A reliability study

BACKGROUND

Patients undergoing total knee arthroplasty (TKA) often experience strength deficits both pre- and post-operatively. As these deficits may have a direct impact on functional recovery, strength assessment should be performed in this patient population. For these assessments, reliable measurements should be used. This study aimed to determine the inter- and intrarater reliability of hand-held dynamometry (HHD) in measuring isometric knee strength in patients awaiting TKA.

METHODS

To determine interrater reliability, 32 patients (81.3% female) were assessed by two examiners. Patients were assessed consecutively by both examiners on the same individual test dates. To determine intrarater reliability, a subgroup (n = 13) was again assessed by the examiners within four weeks of the initial testing procedure. Maximal isometric knee flexor and extensor strength were tested using a modified Citec hand-held dynamometer. Both the affected and unaffected knee were tested. Reliability was assessed using the Intraclass Correlation Coefficient (ICC). In addition, the Standard Error of Measurement (SEM) and the Smallest Detectable Difference (SDD) were used to determine reliability.

RESULTS

In both the affected and unaffected knee, the inter- and intrarater reliability were good for knee flexors (ICC range 0.76-0.94) and excellent for knee extensors (ICC range 0.92-0.97). However, measurement error was high, displaying SDD ranges between 21.7% and 36.2% for interrater reliability and between 19.0% and 57.5% for intrarater reliability. Overall, measurement error was higher for the knee flexors than for the knee extensors.

CONCLUSIONS

Modified HHD appears to be a reliable strength measure, producing good to excellent ICC values for both inter- and intrarater reliability in a group of TKA patients. High SEM and SDD values, however, indicate high measurement error for individual measures. This study demonstrates that a modified HHD is appropriate to evaluate knee strength changes in TKA patient groups. However, it also demonstrates that modified HHD is not suitable to measure individual strength changes. The use of modified HHD is, therefore, not advised for use in a clinical setting.

The assessment of the cervical spine. Part 2: strength and endurance/fatigue

Quantitative documentation of physical deficits such as muscle strength and endurance/fatigue in the cervical spine may provide objective information, not only helping the diagnostic procedures, but also monitoring rehabilitation progress and documenting permanent impairments. The reliable and valid evaluation of muscle strength and endurance both in clinical and research environments are a difficult task since there are many factors that could affect the assessment procedure and the obtained values. The aim of the second part of this critical review is to identify the factors influencing the assessment of strength and endurance/fatigue of the muscles in the cervical spine.

Decrease in peripheral muscle strength and ankle dorsiflexion as long-term side effects of treatment for childhood cancer

BACKGROUND

This study investigated muscle strength, passive ankle dorsiflexion, and their association with motor performance in children after treatment for acute lymphoblastic leukemia, Wilms tumor, B-non-Hodgkin lymphoma, and malignant mesenchymal tumors.

PROCEDURE

Muscle strength was assessed with a hand-held dynamometer and ankle dorsiflexion with a goniometer in 92 and 64 survivors, respectively. Motor performance was measured with the Movement Assessment Battery for Children (movement-ABC). Age at testing: 6.1-12.9 years. Mean time since completing treatment: 3.3 years. Results were compared to 155 healthy controls.

RESULTS

Muscle strength of the survivors was reduced in ankle dorsiflexors on both sides (P < 0.001), wrist dorsiflexors on the non-dominant side (P < 0.001), and pinch grip on the non-dominant (P = 0.001) and dominant side (P = 0.01). Passive ankle dorsiflexion of the survivors was significantly less on both sides (P < 0.01). Movement-ABC percentile score was affected by pinch grip strength on the non-dominant (P < 0.004), and dominant side (P = 0.024) but not by strength of other muscle groups or by passive ankle dorsiflexion.

CONCLUSION

Peripheral muscle strength and ankle dorsiflexion are reduced in the long-term in children treated for cancer with chemotherapy. However, neither decreased muscle strength nor reduced ankle dorsiflexion could completely explain reduced scores on the movement-ABC.

Paretic upper-limb strength best explains arm activity in people with stroke

BACKGROUND AND PURPOSE

The purpose of this study was to determine the relationship among variables of upper-limb impairment, upper-limb performance in activities of daily living (activity), and engagement in life events and roles (participation) in people with chronic stroke.

SUBJECTS

The subjects were 93 community-dwelling individuals with stroke (> or =1 year).

METHODS

This study, which was conducted in a tertiary rehabilitation center, used a cross-sectional design. The main measures of impairment were the Modified Ashworth Scale, handheld dynamometry, sensory testing (monofilaments), and the Brief Pain Inventory. The main measures of activity were the Chedoke Arm and Hand Activity Inventory (CAHAI) and the Motor Activity Log (MAL). The main measure of participation was the Reintegration to Normal Living (RNL) Index.

RESULTS

Paretic upper-limb strength (force-generating capacity) (r=.89, P<.01), grip strength (r=.69, P<.01), and tone (resistance to passive movement) (r=-.80, P<.01) were the impairment variables that were most strongly related to activity. Tone (r=-.23, P<.05) and CAHAI scores (r=.22, P<.05) had a significant, but weak, relationship to participation. Upper-limb strength accounted for 87% of the variance of the CAHAI scores and 78% of the variance of the MAL scores. In the participation models, tone and CAHAI scores accounted for 5% of the variance of the RNL Index scores.

DISCUSSION AND CONCLUSION

Paretic upper-limb strength had the strongest relationship with variables of activity and best explained upper-limb performance in activities of daily living. Grip strength, tone, and sensation also were factors of upper-limb performance in activities of daily living. Increased tone and upper-limb performance in activities of daily living had a weak relationship with participation.

Individuals with the dominant hand affected following stroke demonstrate less impairment than those with the nondominant hand affected

OBJECTIVE

The purpose was to determine if upper extremity impairment and function in individuals with chronic stroke is dependent upon whether the dominant or non-dominant hand is affected.

METHODS

Ninety-three community-dwelling individuals with stroke. The Modified Ashworth Scale (tone), handheld dynamometry (isometric strength), monofilaments (sensation), Brief Pain Inventory (pain), Chedoke Arm and Hand Activity Inventory Motor Activity Log (paretic arm use), and Reintegration to Normal Living Index (participation) were used to form impairment and function models.

RESULTS

Multivariate analysis models (Dominance x Severity) were created for impairment and function variables. There was a significant interaction and main effect of Dominance for the impairment model (P = 0.01) but not the function model (P = 0.75). The dependent variables of tone, grip strength, and pain were all significantly affected by Dominance, indicating less impairment if the dominant hand was affected. All dependent variables except pain were affected by Severity.

CONCLUSION

This study looked at the effect of the dominant hand being affected versus the nondominant in individuals with chronic stroke. Individuals with the dominant hand affected demonstrated less impairment than those with the nondominant hand affected. However, there was no effect of dominance on paretic arm use or performance in activities of daily living. Prospective studies to further explore the issue of hand dominance and poststroke function are suggested.

Outcome assessment in the adult and juvenile idiopathic inflammatory myopathies

Through the recent efforts of multi-center collaborative study groups, a number of measures have been developed and partially validated to assess disease activity, disease damage, and health-related quality of life in adult and juvenile patients with IIM. Preliminary core set domains and core set measures of activity and damage have also been developed for adult and juvenile patients with myositis. Validated definitions of improvement and disability should be forthcoming in the next few years. These extraordinary developments will enable much-needed standardization in the assessment of the IIM, particularly in therapeutic and other clinical research studies. Despite this substantial progress, there is a need to develop more sensitive measures to assess IIM disease activity and damage, to further validate the existing tools, to define their performance characteristics in various IIM subgroups, to develop improved imaging techniques that are also quantitative, and to validate activation markers as surrogate measures. The ongoing cooperation of multiple specialists with expertise in these disorders, combined with emerging novel technologies, should continue to enhance the assessment of myositis. Improved clinical care and more rapid development of new therapies for patients with myositis will be the ultimate gains realized from these efforts.

Muscle force measured using "break" testing with a hand-held myometer in normal subjects aged 20 to 69 years

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.

A static dynamometer measuring simultaneous torques exerted at the upper limb

The majority of available dynamometers are designed to measure force or torque in one specific direction, one joint at a time. For the quantification of motor incoordination in neurological patient populations, these dynamometers provide limited information about the global behavior of the limb under investigation. This report describes the potential use and function of a static dynamometer measuring torques exerted simultaneously at the shoulder (flexion-extension, abduction-adduction, internal-external rotation), elbow (flexion-extension), and forearm (pronation-supination). Orthogonal forces were measured at the arm and wrist using strain gauge transducers interfaced with a laboratory computer. The lever arms were specified to a software program and the joint torques were calculated in real time according to static equilibrium equations. The use of the dynamometer is illustrated by characterizing for one hemiparetic subject, the joints torques recorded at the shoulder, elbow, and forearm during isolated submaximal grip exertions at different force levels on both sides. The torques generated at the shoulder, elbow and forearm during the hand grip tasks on the affected side were significantly higher than those obtained on the nonaffected side and increased with the grip force level. These differences probably reflect the loss of movement selectivity observed following a lesion in the central nervous system. Further studies are currently being undertaken in neurological patient populations to characterize and quantify motor deficits using this dynamometer. As a long term goal, we hope that the method and technologies described here will contribute to the evaluation and rehabilitation of these populations.

International Federation of Clinical Chemistry. Laboratory assessment of protein-energy status

Laboratory and non-laboratory methods for assessing protein-energy nutritional status are reviewed. These are classified into methods for assessing adequacy of recent nutritional intake, methods for assessing whole body status, and tests which assist in the interpretation of these assessments. Each measurement is critically discussed in terms of the rationale for its use, the method of analysis, reference values, technical interference and limitations of methods, the effects of nutritional status and of other factors on the results, its overall usefulness in nutritional assessment, and its value relative to other methods. Non-laboratory tests such as dietary assessment, indirect calorimetry, functional tests and the many methods available for assessment of body composition, including anthropometry, bioelectrical impedance and isotope and imaging techniques, are compared with the clinical chemistry tests in common use, such as nitrogen balance, plasma protein measurements and urinary markers of muscle metabolism. This review provides comprehensive and practical advice on the use and limitations of these tests in the assessment of protein-energy nutritional status of a group, or of an individual patient.

Isometric strength of rearfoot inversion and eversion in nonsupported, taped, and braced ankles assessed by a hand-held dynamometer

Previous studies have reported a reduction of athletic performance while wearing ankle orthoses. The present study investigated whether or not this observed reduction in performance was the result of a restriction of the associated muscles by the orthoses. Specifically, 36 male undergraduate students participated in this study to compare the effects of unsupported, nonelastic adhesive-taped, and Swede-O, New Cross, Air-Stirrup, and STS braced ankles on isometric strength of rearfoot inversion and eversion as assessed by a hand-held dynamometer. Subjects were stabilized in a seated position so that lower limb movement was restricted to the ankle. Each subject performed isometric inversion and eversion contractions under all six ankle conditions with the dominant foot. The isometric force was recorded from each of three trials during rearfoot inversion and eversion under each support condition. One-way repeated measures ANOVAs failed to detect any significant differences between the six testing conditions for inversion and eversion for both mean and peak force values. No alterations were observed in the isometric forces recorded during rearfoot inversion and eversion, thus, indicating that the orthoses did not constrict the lower leg musculature. These results suggest that, when selected by the clinician, any brace used in this study would not be detrimental to lower leg strength. J Orthop Sports Phys Ther 1992;15(5):229-235.

Effects of muscle group and placement site on reliability of hand-held dynamometry strength measurements

Studies of measuring muscle strength with hand-held dynamometers have produced a variety of results. The purpose of this research was to further investigate the effect of muscle group and placement site on reliability. The purpose of Part I of this study was to examine reliabilities of force measurements generated by four specific muscle groups using a hand-held dynamometer (HHD). Part II's purpose was to determine the effects of HHD placement site on the variability of HHD force measurements. In Part I, two testers obtained measurements of right shoulder abductor, wrist extensor, hip flexor, and ankle dorsiflexor forces in 20 subjects. Two-way analysis of variance indicated a main effect due to tester, but no tester by session interaction and no main effect due to session (p < 0.5). Intraclass correlation coefficients ranged from .76-.93 for within-session, intratester reliabilities, .67-.84, for between-session intratester reliabilities, and .30-.83 for within-session, intertester reliabilities. Reliability tended to be higher when HHD placement sites were farther from joint centers. Part II explored the hypothesis that HHD forces would be less variable if measured distally. One tester measured shoulder abductor forces for 30 subjects at three sites on the upper extremity. Bartlett's Test for homogeneity of variance indicated a lower variability at the distal placement site (p < 0.05). J Orthop Sports Phys Ther 1992;15(5):236-242.

Hand-held Dynamometer Measurements: Tester Strength Makes a Difference

Three examiners with measurably different strengths and three muscle groups with distinctly different maximum force productions were used to investigate the effect of tester strength on the magnitude and reliability of hand-held dynamometer (HHD) force measurements. Each examiner measured the shoulder external rotator, elbow flexor, and knee extensor muscles of 27 healthy adults twice during two sessions (one week apart). Intrarater/intrasession, intrarater/intersession, and interrater/intrasession reliability coefficients (ICCs) were calculated. Interrater ICCs decreased in magnitude (.932 to .226) as the tested muscle groups increased in force production. Intrarater/intersession ICCs indicated a similar trend. High intrarater/intrasession and interrater/intrasession ICCs calculated from shoulder external rotator measurements indicated that HHD testing for muscle groups generating a mean maximum force of about 120 N may be reliable for clinicians with strengths equal to or exceeding those of the weakest tester in this study. Above 120 N, tester strength appeared to be a major determinant of the magnitude and reliability of the forces measured with a HHD. Further investigation into the relationship between tester strength and the intrarater and interrater reliability of HHD measurements is warranted. J Orthop Sports Phys Ther 1991;13(4):191-198.

The validity and reliability of hand-held dynamometry in assessing isometric external rotator performance

The validity and reliability of hand-held dynamometry and Cybex dynamometry were investigated using maximal isometric contractions of the external rotators of the shoulder in 14 healthy male subjects. Three maximum voluntary contractions were recorded from each subject by a hand-held dynamometer and a Cybex isokinetic dynamometer at two testing sessions approximately 1 week apart. Analysis of variance did not reveal any significant differences between the mean peak torques obtained with either instrument or between days. The intrarater reliability was clearly established for both the hand-held dynamometer (r = 0.986) and Cybex dynamometer (r = 0.993). Within-day correlations between the two instruments accounted for 27% (day 1) and 60% (day 2) of the explainable variance. This suggests that although both techniques produced identical peak torque values and measured the same element of performance-strength, they did so in a slightly different manner. The possible nature of these differences is discussed.J Orthop Sports Phys Ther 1988;10(6):213-217.

Hand-held dynamometry; stability of muscle strength over multiple measurements

Repeated measurements of elbow flexion force were obtained to determine the stability of muscle strength over multiple measurements (four) with a hand-held dynamometer. Thirty-one healthy, adult women were tested. Although the force of the fourth trial was found to differ significantly from the force of the first and second trials, the reliability of the procedure was very high (ICC=0·955). The first trial was usually the strongest, but not alqays. The coefficient of variation of the first two efforts did not decrease with the inclusion of the third and fourth trials in its calculation. If the fourth trial is excluded, the measurements demonstrate stability. Given this finding and the finding that the earlier efforts were usually the strongest, little justification for multiple measurements of strength is apparent in the subjects tested.