Very late spinal accessory nerve to infraspinatus nerve transfer to restore glenohumeral external rotation in brachial plexus birth injury
Very late spinal accessory nerve to infraspinatus nerve transfer to restore glenohumeral external rotation in brachial plexus birth injury

Very late spinal accessory nerve to infraspinatus nerve transfer to restore glenohumeral external rotation in brachial plexus birth injury

Plast Reconstr Surg. 2025 Sep 3. doi: 10.1097/PRS.0000000000012418. Online ahead of print.

ABSTRACT

BACKGROUND: Poor recovery of active glenohumeral external rotation (aGHER) after brachial plexus birth injury (BPBI) is common. Late spinal accessory nerve to infraspinatus motor branch (SAN-IS) transfer has been reported as effective. We investigated its efficacy in children over 4 years with BPBI.

METHODS: This case series involved children with no aGHER undergoing SAN-IS transfer. Indications included absent aGHER in shoulder abduction and a positive external rotation drop test. Subscapularis release was done for passive GHER (pGHER) <30º in patients without glenohumeral dysplasia, while external derotational humeral osteotomy (DHOT) was performed for those with dysplasia and pGHER <0º. Data collected included demographics, Narakas group classification, preoperative and postoperative hand-to-neck Mallet scores, postoperative aGHER, aGHER strength (British Medical Research Council scale), and parental satisfaction.

RESULTS: Twenty-six patients, with a mean age of 9.9 years (range 4-26) and mean follow-up of 27.9 months (range 12-74), were included. Five patients (19%) had a concurrent upper subscapularis release, and eight (31%) underwent DHOT. Infraspinatus was macroscopically normal and contractile in all but one case. Twenty-one patients (80%) achieved a mean aGHER of 71º (range 60-80). Of these, 90% scored M4 on the BMRC scale, and 85% had a hand-to-neck Mallet score of 4. Shoulder forward flexion improved a mean of 35º (range 20-60º) in 40% of patients. Six parents were satisfied, and 20 were extremely satisfied.

CONCLUSIONS: Late SAN-IS transfer is both effective and safe for restoring aGHER in patients over 4 years old with BPBI.

PMID:40920464 | DOI:10.1097/PRS.0000000000012418