The influence of scapular depression on upper limb neurodynamic test responses

Muscle responses during radial nerve-biased upper limb neurodynamic test in asymptomatic individuals: a cross-sectional study

This laboratory cross-sectional study aimed at explore the muscle response (MR) of the upper trapezius, infraspinatus, biceps brachii and extensor carpi radialis brevis (ECRB) during the radial nerve-biased upper limb neurodynamic test (RN-ULNT) in healthy participants. Myoelectric activity was stage-by-stage recorded during two sequencing variants of the RN-ULNT: S1, in which elbow extension was the last movement; and S2, in which wrist flexion was the last movement. Final elbow and wrist joint angle and sensory response (SR) in five zones (Z1-Z5) were also registered. MR was qualitatively categorized as 'absent' (No-MR), 'true' (TMR) or 'uneven' (UMR). In both sequences, significant increases in muscle activity occurred mostly during shoulder abduction and elbow extension (p ≤ 0.009). Also, elbow extension but not wrist flexion increased the activity of the ECRB muscle (p ≤ 0.009). S2 showed significantly higher upper trapezius (p = 0.04) and biceps brachii (p = 0.036) muscle activity during wrist flexion, and higher report of SR in Z1 and Z4 (p < 0.001) compared to S1. Only the ECRB muscle showed significant differences in the MR type between S1 and S2 (TMR, p = 0.016; UMR, = 0,012). Our results may be useful in the assessment of upper limb musculoskeletal disorders.

Assessing the Effects of Scapular Positioning on the Morphology of the Median Nerve During Upper Limb Tension Test 1 (ULTT1)

Objective:

The upper limb tension test 1 (ULTT1) is commonly used by physical therapists for patients with complaints of radiating symptoms in their upper extremity following the path of the median nerve. Clinicians typically perform similar testing positions for patients, except for scapular position, which may vary between scapular blocking and scapular depression. This may alter the test results based on this positioning. The purpose of this study was to determine if there is a significant difference in median nerve morphology during the ULTT1 between resting and two scapular testing positions.

Materials and Methods:

Thirty healthy participants, 18 to 65 years of age, were tested using the ULTT1 in both blocked and depressed scapular positions. The height and width of the median nerve were measured by diagnostic sonography. Paired t tests were utilized to compare baseline, blocked, and depressed scapular positions with the ULTT1.

Results:

No statistically significant difference in height or width was found between resting, blocked, or depressed scapular positioning.

Conclusion:

There were inconclusive results regarding the morphology of the median nerve in this study.

Key Takeaways

Inconclusive results on nerve morphology comparing two scapular positions during the ULTT1. Research may be conducted on symptomatic patients to assist with more reliable test findings related to ULTT1.

The effect of axillary crutch length on upper limb kinematics during swing-through gait

BACKGROUND

Axillary crutches are commonly used in rehabilitation. Inappropriately fit crutches may result in upper limb pain or injury.

OBJECTIVE

To investigate the effects of axillary crutch length on upper limb kinematics to better understand potential injury mechanisms. It was hypothesized that crutches that were longer or shorter than standard-fit crutches would alter upper limb kinematics.

DESIGN

Cross-sectional.

SETTING

Gait laboratory.

PARTICIPANTS

Fifteen healthy males with no prior crutch experience.

INTERVENTIONS

Participants were fit with axillary crutches using standardized methods, as well as with crutches that were 5 cm longer and 5 cm shorter. Participants performed swing-through gait (1.20 ± 0.07 ms^-1 ) with all crutch lengths in randomized order. Kinematics were recorded using an optical motion-tracking system and joint angles for the scapula, shoulder, elbow, and wrist were computed.

MAIN OUTCOME MEASURES

The effects of crutch length on joint range of motion (ROM) and joint angles at initial crutch contact were analyzed using multivariate analysis (Hotelling's T² ; α = .025) and simultaneous confidence intervals (CI).

RESULTS

The long-standard crutch fit comparison showed effects across all joints (ROM p = .009; initial contact p < .001). Longer crutches resulted in greater scapular upward rotation (mean difference [95% CI] ROM: 1.0 [-0.2 to 2.2]; initial contact: -2.7 [-4.4, -1.1]) and shoulder abduction (ROM: 0.8 [-0.1 to 1.8]; initial contact: -1.9 [-4.1 to 0.3]). Crutch length also had effects across all joints for the short-standard fit comparison (ROM p = .004; initial contact p = .016). Shorter crutches resulted in greater scapula downward rotation (2.2 [-0.4 to 4.8]) and greater shoulder adduction (2.5 [-0.6 to 5.6]) at initial contact. Shorter crutches also reduced shoulder flexion/extension ROM (-2.5 [-4.4 to -0.6]).

CONCLUSIONS

Altered crutch length results in scapular and shoulder kinematic deviations that may present risk factors for upper limb injury with crutch-walking. This may underline the importance of appropriate device fitting to reduce injury risk in crutch users.

Agreement and Reliability of Median Neurodynamic Test 1 and Resting Scapular Position

Objective

The purposes of this study were to determine whether there are differences between the dominant and nondominant arms for the Median Neurodynamic Test 1 (MNT 1); whether there are differences between men and women on the MNT 1; the reliability of an assessment of resting scapular position; the reliability of the MNT 1; and the frequency and percentage of sensory responses that are present during the MNT 1 in the asymptomatic population.

Methods

This was a reliability and agreement study. It included asymptomatic students enrolled in the college of health professions and the college of nursing at a university. The Mann-Whitney U was used to determine whether there were any differences between the dominant and nondominant sides and between sexes for elbow extension range of motion and for sensory responses on the numeric pain rating scale when performing the MNT 1. A χ² analysis was used to determine whether there were any differences between sexes and between dominant and nondominant upper extremities for sensory-response location, sensory-response type, and structural differentiation for raters 1 and 2. The intraclass correlation coefficient (ICC_2,3) was used to determine the intertester and intratester reliability for the degrees of elbow extension attained during testing.

Results

Reliability for degrees of elbow extension and strength of the sensory response was excellent (ICC_2,3 ˃ 0.75) and substantial (κ ≥ 0.68), respectively. Resting scapular position and all other components of the MNT 1 demonstrated statistically significant side-to-side differences and κ values ranging from 0.23 to 0.88.

Conclusion

Elbow extension and magnitude of sensory response are reliable components of the MNT 1 that are not different between the dominant and nondominant sides in the asymptomatic population.

Reliability of the beighton score and impact of generalized joint mobility and resting scapular position on Median Neurodynamic Test 1

INTRODUCTION

There is a lack of understanding of the impact of generalized joint mobility, joint hypermobility, and resting scapular position on neurodynamic testing of the median nerve. The objectives of the study were to determine: 1) the reliability of the Beighton score (BS) with and without the cutoff score for general joint hypermobility (GJH); 2) if there are differences in the Median Neurodynamic Test 1 (MNT 1) based on the Beighton cutoff score for GJH; 3) if there are differences in the MNT 1 based on an assessment of resting scapular position; 4) if there are relationships between the BS with and without the cutoff score for GJH, resting scapular position, and MNT 1.

METHODS

Testing was performed by two testers at two-time intervals at least 1 week apart. The population of interest was healthy asymptomatic adults. The outcome measures included the BS, resting scapular position, and MNT 1.

RESULTS

Intraclass correlation coefficients (ICC_2,1) were 0.52 for intertester reliability at visit 1 and 0.86 at visit 2, with intratester reliability of 0.88 for Tester 1 and 0.71 for Tester 2 for the BS. Intertester prevalence-adjusted bias-adjusted kappa (PABAK) values for the Beighton GJH cutoff scores were 0.80-0.84 and 0.80 to 0.92 for intratester reliability. There were no statistically significant differences or relationships for any of the other variables of interest.

CONCLUSION

Joint mobility and resting scapular position are not confounding variables when performing MNT 1 in an asymptomatic population.

Influence of neural mobilization of lower limbs on the functional performance and dynamic balance in asymptomatic individuals: a cross-over randomized controlled trial

Purpose. To verify the influence of neural mobilization (NM) applied to the lower limbs on functional performance and dynamic balance in asymptomatic individuals. Methods. The total of 30 asymptomatic participants (15 women and 15 men; age, 30.1 ± 6.7 years; height, 1.70 ± 0.1 m; body mass, 73.1 ± 13.4 kg) were enrolled in this cross-over randomized controlled trial. The participants received NM of the femoral, sciatic, and tibial nerves, as well as static stretching (SS) of the following muscles: hamstring, lumbar, piriformis, hip adductors, hip flexors, quadriceps, and triceps surae. The order of applying NM and SS was randomly decided and the interventions were performed at least 48 hours apart. Functional performance was measured by performance in vertical jump (VJ) and dynamic balance was measured with the Star Excursion Balance Test (SEBT). Results. There were no differences between NM and SS for height (cm) in VJ (p = 0.16) or in the distance reached (%) in the SEBT, normalized by lower limb length (dominant limb: anterior, p = 0.35; posterolateral, p = 0.69; posteromedial, p = 0.50 / non-dominant limb: anterior, p = 0.68; posterolateral, p = 1.00; posteromedial, p = 0.77). Conclusions. NM did not exert any influence on functional performance or dynamic balance. Thereby, having no positive or negative impact on performance, NM can be used at any time of treatment.

Impact of shoulder internal rotation on normal sensory response during ulnar nerve-biased neurodynamic testing of asymptomatic individuals

OBJECTIVE

To determine if substitution of shoulder internal rotation for external rotation during the upper limb neurodynamic test (ULNT₃) evokes comparable ulnar nerve sensory responses in asymptomatic individuals.

METHODS

Range of motion, quality, quantity, and distribution of sensory responses in 50 asymptomatic individuals during the traditional ULNT₃ were compared to identical measures during an experimental maneuver using shoulder internal rotation. Quality and quantity of sensory responses were recorded using a 10-cm visual analog scale.

RESULTS

Means of sensory responses for traditional and experimental maneuvers, respectively, were as follows: stretching, 3.84 ± 8.85 and 5.38 ± 2.85 cm; burning, 1.82 ± 2.82 and 2.50 ± 3.10 cm; tingling, 2.13 ± 3.12 and 2.18 ± 2.97 cm; and numbness, 1.04 ± 2.17 and 1.01 ± 2.03 cm. A moderate to strong correlation (ICC = 0.51-0.86) was shown to exist between maneuvers; this relationship was significant (p = .001).

DISCUSSION

Results of this study provide evidence that there was no appreciable difference in sensory responses with regard to burning and tingling when substituting shoulder internal rotation for external rotation during the ULNT₃. The results also suggest that there were only marginal differences in the sensory responses of stretching and numbness during the same substitution.

CONCLUSION

Patients who have limited glenohumeral external rotation due to pain, instability, and/or articular limitation may benefit from this substitution when presenting with signs of ulnar nerve pathodynamics. Further research will be needed to validate this maneuver in a symptomatic population.

LEVEL OF EVIDENCE

Level 2b.

Acute effects of neural mobilization and infrared on the mechanics of the median nerve

[Purpose] This study analyzed the acute effects of infrared and neural mobilization on the median nerve on the range of elbow extension of the dominant limb. [Subjects and Methods] Forty participants from university, neurologically asymptomatic, 12 males and 28 females (22.8 ± 1.9 years), were randomly divided into four groups: Group 1 (control) rested for 25 minutes in the supine position; Group 2 received the specific neural mobilization for the median nerve; Group 3 received an application of infrared for 15 minutes on the forearm; Group 4 received the same application of infrared followed by neural mobilization. The goniometric parameters of elbow extension were evaluated after the intervention. [Results] Significant differences of extension value were observed between Group 1 and Group 3 (15.75 degrees), and between Group 1 and Group 4 (14.60 degrees), and the average higher in Group 3 (26.35 degrees). [Conclusion] This research provides new experimental evidence that NM in relation to superficial heat produces an immediate effect on elbow range of motion versus NM isolated.

Ulnar nerve neurodynamic test: study of the normal sensory response in asymptomatic individuals

STUDY DESIGN

Cross-sectional study.

OBJECTIVES

To describe and analyze normal sensory responses to the ulnar upper-limb neurodynamic test (ULNT3) and to investigate the influence of sex and arm dominance.

BACKGROUND

Neurodynamic tests are commonly used in the clinical evaluation of patients with musculoskeletal pain disorders. While the normal responses of other upper-limb neurodynamic tests have been previously investigated, there are no studies that have reported the normal responses for the ULNT3.

METHODS

A total of 68 asymptomatic individuals between 18 and 50 years of age volunteered to participate in the study. Of these, 57 (29 women, 28 men) were eligible for the study. The variables measured were pain intensity using a numeric rating scale, shoulder abduction angle, and quality and distribution of symptoms at the point of pain tolerance of the ULNT3.

RESULTS

There were statistically significant differences in pain intensity and shoulder abduction angle between the sexes, with women having higher perceived pain and lower shoulder angle than men (P<.05). There was a significant difference of 6.6° (95% confidence interval: 1.1°, 12.1°) in shoulder abduction angle during the ULNT3 (P<.05) between the dominant arm and nondominant arm. The symptoms most often described during application of the ULNT3 were stretching (90%), followed by pain, and the most frequent location of symptoms was the anteromedial half of the forearm.

CONCLUSION

The results of this study provide the normal shoulder abduction angle and quality and distribution of symptoms for the ULNT3. These data can be used by clinicians as a reference when using the ULNT3 in their clinical reasoning and decision making.

Mechanosensitivity in the upper extremity following breast cancer treatment

STUDY DESIGN

Descriptive, cross-sectional.

INTRODUCTION

Breast cancer (BC) treatments place the nervous system at risk, which may contribute to upper extremity (UE) mechanosensitivity.

PURPOSE OF THE STUDY

To evaluate elbow extension range of motion (EE-ROM) during upper limb neurodynamic testing (ULNT) post-BC treatment.

METHODS

ULNT EE-ROM was measured for 145 women post-BC treatment. Women were sub-grouped by presence/absence of pain and lymphedema.

RESULTS

Mean EE-ROM during ULNT1 was -22.3° (SD 11.9°) on the unaffected limb and -25.99° (SD 13.1°) on the affected limb. The women with pain and lymphedema had the greatest limitation in EE-ROM during ULNT1 testing, particularly of their affected limb (-33.8°, SD 12.9). Symptoms were reported more frequently in the affected chest, shoulder, arm, elbow, and hand. The intensity of symptoms was greater at the affected chest (p = 0.046), shoulder (p = 0.033) and arm (p = 0.039).

CONCLUSIONS

Women with lymphedema and pain after BC treatment may present with altered neural mechanosensitivity.

LEVEL OF EVIDENCE

3a.