Comparative study of phrenic and partial ulnar nerve transfers for elbow flexion after upper brachial plexus avulsion: A retrospective clinical analysis

The Effectiveness of Different Nerve Transfers in the Restoration of Elbow Flexion in Adults Following Brachial Plexus Injury: A Systematic Review and Meta-Analysis

PURPOSE

Restoration of elbow flexion is an important goal in the treatment of patients with traumatic brachial plexus injury. Numerous studies have described various nerve transfers for neurotization of the musculocutaneous nerve (or its motor branches); however, there is uncertainty over the effectiveness of each method. The aim of this study was to summarize the published evidence in adults with traumatic brachial plexus injury.

METHODS

Medline, Embase, medRxiv, and bioRxiv were systematically searched from inception to April 12, 2021. We included studies that reported the outcomes of nerve transfers for the restoration of elbow flexion in adults. The primary outcome was elbow flexion of grade 4 (M4) or higher on the British Medical Research Council scale. Data were pooled using random-effects meta-analyses, and heterogeneity was explored using metaregression. Confidence intervals (CIs) were generated to the 95% level.

RESULTS

We included 64 articles, which described 13 different nerve transfers. There were 1,335 adults, of whom 813 (61%) had partial and 522 (39%) had pan-plexus injuries. Overall, 75% of the patients with partial brachial plexus injuries achieved ≥M4 (CI, 69%-80%), and the choice of donor nerve was associated with clinically meaningful differences in the outcome. Of the patients with pan-plexus injuries, 45% achieved ≥M4 (CI, 31%-60%), and overall, each month delay from the time of injury to reconstruction reduced the probability of achieving ≥M4 by 7% (CI, 1%-12%).

CONCLUSIONS

The choice of donor nerve affects the chance of attaining a British Medical Research Council score of ≥4 in upper-trunk reconstruction. For patients with pan-plexus injuries, delay in neurotization may be detrimental to motor outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

A systematic review and meta-analysis of patient-reported outcomes following nerve transfer surgery for brachial plexus injury

OBJECTIVE

The purpose of this systematic review and meta-analysis was to determine the effect of nerve transfer surgery for brachial plexus injury (BPI) on patient-reported outcomes.

LITERATURE SURVEY

MEDLINE, EMBASE, and CINAHL were searched and screened in duplicate for relevant studies on September 25, 2019 and repeated June 24, 2020.

METHODOLOGY

The patient population included male and female patients who received nerve transfer surgery for BPI. Further inclusion criteria were: (1) all levels of evidence; (2) published in English; (3) conducted in humans; and (4) report of patient-reported outcome. Two reviewers independently abstracted data regarding injury type, surgical technique, surgical timing, follow-up duration, strength, and patient-reported outcome measures. Quality was assessed in duplicate using the Methodological Index for Non-Randomized Studies criteria.

SYNTHESIS

Twenty-one studies involving 464 participants were included in analyses. The mean age ± SD was 32.4 ± 1.8 (range: 5-77) and 89.2% of included participants were male. The mean time to surgery was 5.6 ± 0.6 months and the mean follow-up time was 48.1 ± 8.4 months. The most used patient-reported outcome was the Disabilities of Arm, Shoulder and Hand (DASH), where scores variably improved postoperatively, although the degree of disability remained high. Return to work was reported in five studies, with 66.0% of participants returning to work. Patient satisfaction was assessed in four studies with an overall satisfaction proportion of 64.0%. Pain was assessed in 12 studies using various measures. In studies reporting pain intensity postoperatively, 29.3% of patients were "pain-free" or had "no pain."

CONCLUSIONS

Patient-reported outcomes following nerve transfer for BPI are infrequently reported in the literature. Although patient-reported outcomes demonstrate variable postoperative improvement, there is evidence of ongoing limitations and postoperative DASH scores report a high degree of ongoing disability. Future studies with greater reporting as well as validation of patient-reported outcomes within BPI are warranted.

Optimal Donor Nerve to Restore Elbow Flexion After Traumatic Brachial Plexus Injury: A Systematic Review and Meta-Analysis

BACKGROUND

Traumatic brachial plexus injuries (BPIs) often lead to devastating upper extremity deficits. Treatment frequently prioritizes restoring elbow flexion through transfer of various donor nerves; however, no consensus identifies optimal donor nerve sources.

OBJECTIVE

To complete a meta-analysis to assess donor nerves for restoring elbow flexion after partial and total BPI (TBPI).

METHODS

Original English language articles on nerve transfers to restore elbow flexion after BPI were included. Using a random-effects model, we calculated pooled, weighted effect size of the patients achieving a composite motor score of ≥M3, with subgroup analyses for patients achieving M4 strength and with TBPI. Meta-regression was performed to assess comparative efficacy of each donor nerve for these outcomes.

RESULTS

Comparison of the overall effect size of the 61 included articles demonstrated that intercostal nerves and phrenic nerves were statistically superior to contralateral C7 (cC7; P = .025, <.001, respectively) in achieving ≥M3 strength. After stratification by TBPI, the phrenic nerve was still superior to cC7 in achieving ≥M3 strength (P = .009). There were no statistical differences among ulnar, double fascicle, or medial pectoral nerves in achieving ≥M3 strength. Regarding M4 strength, the phrenic nerve was superior to cC7 (P = .01) in patients with TBPI and the ulnar nerve was superior to the medial pectoral nerve (P = .036) for partial BPI.

CONCLUSION

Neurotization of partial BPI or TBPI through the intercostal nerve or phrenic nerve may result in functional advantage over cC7. In patients with upper trunk injuries, neurotization using ulnar, median, or double fascicle nerve transfers has similarly excellent functional recovery.

Elbow flexion reconstruction with nerve transfer or grafting in patients with brachial plexus injuries: A systematic review and comparison study

INTRODUCTION

Posttraumatic brachial plexus (BP) palsy was used to be treated by reconstruction with nerve grafts. For the last two decades, nerve transfers have gained popularity and believed to be more effective than nerve grafting. The aim of this systematic review was to compare elbow flexion restoration with nerve transfers or nerve grafting after traumatic BP injury.

METHODS

PRISMA-IPD structure was used for 52 studies included. Patients were allocated as C5-C6 (n = 285), C5-C6-C7 (n = 150), and total BP injury (n = 245) groups. In each group, two treatment modalities were compared, and effects of age and preoperative interval were analyzed.

RESULTS

In C5-C6 injuries, 93.1% of nerve transfer patients achieved elbow flexion force ≥M3, which was significantly better when compared to 69.2% of nerve graft patients (p < 0.001). For improved outcomes of nerve transfer patients, shorter preoperative interval was a significant factor in all injury patterns (p < 0.001 for C5-C6 injuries and total BP injuries, p = 0.018 for C5-C6-C7 injuries), and young age was a significant factor in total BP injury pattern (p = 0.022).

CONCLUSIONS

Our analyses showed that nerve transfers appear superior to nerve graftings especially in patients with a C5-C6 injury. Unnecessary delays in surgery must be prevented, and younger patients may have more chance for better recovery.

LEVEL OF EVIDENCE

Level II.