Functional outcomes of infants with Narakas grade 1 birth-related brachial plexus palsy undergoing neurotization compared with infants who did not require surgery

Outcomes of Spinal Accessory-to-Suprascapular Nerve Transfers for Brachial Plexus Birth Injury

PURPOSE

The results of a spinal accessory nerve-to-suprascapular (SAN-SSN) nerve transfer for brachial plexus birth injuries (BPBIs) have thus far been presented only in limited case series. Our study evaluates the recovery of shoulder function of patients who underwent an SAN-SSN for BPBI as an isolated procedure or as part of a multinerve reconstruction (MNR) surgery.

METHODS

We retrospectively reviewed the medical records of patients at a single institution who underwent an SAN-SSN after BPBI. Inclusion criteria were patients with both preoperative and a minimum 12-months postoperative active movement scale (AMS) scores. Patients for whom the primary surgery involved tendon transfers were excluded. The primary outcome measures were AMS scores for shoulder abduction, forward flexion, and external rotation and secondary outcomes included the need for further shoulder surgery to improve function.

RESULTS

Seventy-three patients met the inclusion criteria. Forty-three patients (58.9%) obtained functional shoulder motion (AMS ≥ 6) of at least 1 of 3 planes (abduction/flexion/external rotation) following surgery, with 13 patients (17.8%) achieving full recovery of 1 of these shoulder motions against gravity (AMS = 7). Fifty-six patients (76.7%) did not undergo subsequent tendon transfers or corrective osteotomies to augment shoulder function. The MNR procedures were performed in 46 patients (63%), of whom 45.7% gained a functional recovery. In 27 patients for whom SAN-SSN nerve transfer was conducted in isolation, 81.5% gained functional shoulder motion. However, isolated SAN-SSNs were conducted at a later age than MNR procedures (13.2 vs 4.8 months) and had higher preoperative AMS scores. The anterior and posterior approaches for SAN-SSN were both found to be effective when used for SAN-SSN in BPBI. When the follow-up duration cutoff was set to 3 years, the outcomes were found to be superior.

CONCLUSIONS

In 76.7% of the patients, SAN-SSN was able to recover function that was sufficient to prevent tendon transfers and corrective osteotomies. A cutoff of 3 postoperative years should be used as a benchmark for analyzing the results of this procedure.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

The natural history and management of brachial plexus birth palsy

Brachial plexus birth palsy (BPBP) is an upper extremity paralysis that occurs due to traction injury of the brachial plexus during childbirth. Approximately 20 % of children with brachial plexus birth palsy will have residual neurologic deficits. These permanent and significant impacts on upper limb function continue to spur interest in optimizing the management of a problem with a highly variable natural history. BPBP is generally diagnosed on clinical examination and does not typically require cross-sectional imaging. Physical examination is also the best modality to determine candidates for microsurgical reconstruction of the brachial plexus. The key finding on physical examination that determines need for microsurgery is recovery of antigravity elbow flexion by 3-6 months of age. When indicated, both microsurgery and secondary shoulder and elbow procedures are effective and can substantially improve functional outcomes. These procedures include nerve transfers and nerve grafting in infants and secondary procedures in children, such as botulinum toxin injection, shoulder tendon transfers, and humeral derotational osteotomy.