Entrapment of median nerve after elbow fracture dislocations: expected surgical time frame based on cadaver study

INTRODUCTION

Median nerve injuries occur in approximately 3% of pediatric elbow fracture dislocations. These rare injuries can be difficult to diagnose, and the results are poor in delay cases. Surgical timing is one of the most important prognostic factors. We aimed to present three patients with median nerve palsy who were referred to our clinic late, and according to these cases, we emphasized the expected time frame for exploration based on our anatomical cadaver study.

MATERIALS AND METHODS

Between 2008 and 2010, three patients were referred to our clinic because of median nerve paralysis after a treated elbow dislocation. The mean interval between injury and referral was 15 (min: 13-max: 18) months, and the mean age of the patients was 15 (13-18) years. Neurolysis was performed in two patients, and for the third patent, after neurolysis, axonal continuity was observed to be disrupted so sural nerve grafting was performed with four cables. Tendon transfers were performed in all patients. A total number of 20 upper extremities of 10 cadavers were dissected. Due to its proximal innervation and ease of assessment, the muscle innervation of the flexor pollicis longus (FPL) was planned to be evaluated. The distance from the medial epicondyle is calculated in the cadaver study where the nerve injury is found.

RESULTS

The mean length from the medial epicondyle to the motor innervation of FPL was calculated in each specimen and found to be 101.99 millimeters (mm) (range: 87.5-134.2). The mean longest innervation of FPL was 110.83 mm from (range 87.5-148.1) the medial epicondyle calculated by including each specimens longest nerve length. Knowing that the healing time of a nerve lesion is 1 mm per day, we calculated that the recovery of FPL would take approximately 4 months.

CONCLUSION

When nerve healing is expected to be 1 mm a day in axonotmesis type injury, after the median nerve palsy following elbow dislocation, thumb flexion should be achieved in the following 4 months generally if the nerve was not entrapped in the joint. This cadaver-based study objectively defined how long to wait for the innervation of the FPL in median nerve injuries in elbow fracture dislocations.

Tendon Transfers to Restore Shoulder Function for Obstetrical Brachial Plexus Palsy: A Systematic Review of the Literature

BACKGROUND

Obstetrical brachial plexus palsy (OBPP) is a relatively common stretch injury of the brachial plexus sustained during delivery. Tendon transfers are commonly performed to improve shoulder function among patients with OBPP. Although several techniques for the surgical management of OBPP exist, it is unclear whether tendon transfers to the rotator cuff vs. posterior humerus yield different outcomes.

METHODS

A systematic search in PubMed, Web of Science, the Cumulative Index to Nursing and Allied Health Literature, the Cochrane Library, and Google Scholar up to January 1, 2021, was performed. Relevant publications were classified by surgical technique of tendon transfers to the rotator cuff or posterior humerus. The standard mean difference (SMD) and 95% confidence intervals were calculated to compare preoperative and postoperative aggregate Mallet scores as well as abduction and external rotation scores using the Mallet scale. A p value of <0.01 was considered significant.

RESULTS

Data from 26 studies and 951 patients (46.2% male patients) with a mean age of 68.9 ± 29.3 months were included. Eight hundred three patients underwent tendon transfer to the rotator cuff and 148 to the posterior humerus. The average postoperative follow-up period was 45.2 ± 21.7 months. The pooled cohort had an overall improvement in postoperative aggregate Mallet scores (SMD = 5.53, p < 0.001), abduction scores (SMD = 1.79, p < 0.001), and external rotation scores (SMD = 1.99, p < 0.001). Tendon transfer to the rotator cuff had a greater postoperative improvement in abduction (SMD = 1.90, p < 0.001) than transfer to the posterior humerus (SMD = 1.32, p < 0.001) while both techniques yielded similar improvements in external rotation (rotator cuff SMD = 2.01, p < 0.001, posterior humerus SMD = 1.98, p < 0.001).

CONCLUSION

This is the first systematic review comparing outcomes for tendon transfers to the rotator cuff vs. the posterior humerus for improving shoulder function in patients with OBPP. Overall, tendon transfers are an effective treatment for improving shoulder function. Transfer of the latissimus dorsi and teres major to the rotator cuff compared with transfer to the posterior humerus results in greater improvement in abduction while both techniques have similar results in improving external rotation.

LEVEL OF EVIDENCE

Level I Systematic review of Level I and Level II studies.

Intercostal or ulnar nerve: Which donor nerve is to be used for reanimation of elbow flexion?

BACKGROUND

In total brachial plexus injury, intercostal nerves (ICNs) are used as donor nerves to restore the elbow flexion; albeit in upper brachial plexus injury (BPI), ulnar nerve provides a source of motor axons for this purpose. The present study set out to compare the restoration of elbow flexion by using these two donor nerves.

METHODS

Between 2010 and 2013, 24 adult patients with upper-middle BPI and 15 patients with total BPI undergoing elbow flexion restoration surgery were studied. Motor fascicle of flexor carpi ulnaris branch of ulnar nerve (mFCU nerve) procedure was utilized in upper-middle BPI, as well as transfer of ICN to biceps branch of the musculocutaneous nerve (MCN) in total BPI. Both techniques included sectioning, rerouting, and direct suturing of the biceps branch of the MCN. Follow-up consisted serial clinical examinations and EMG-NCV tests. Motor strength was recorded according to the British Medical Research Council grading system in that the results were reported as nonfunctional (grades M0-M2) and functional (grades M3-M5).

RESULT

No significant difference was documented between the Oberlin procedure and ICN-MCN transfer in terms of reinnervation results (P = 0.6). However, a significant difference in restoration of muscle force was found between the mFCU (95.83%) and ICN-MCN transfers (66.66%) (P = 0.02).

CONCLUSION

The evidence from the present study indicates that although ICN-MCN transfer is a viable method for reanimation of elbow flexion in BPI, mFCU nerve is a better donor if exists.