# Lower Subscapular Nerve Hydrodissection and Subscapularis Re-education for Residual Anterior Shoulder Pain After Superior Labrum Anterior to Posterior Debridement: A Case Report

## TL;DR

A case report shows that combining nerve hydrodissection and targeted therapy can effectively treat persistent shoulder pain after surgery.

## Contribution

Introduces a novel treatment combining LSN hydrodissection and subscapularis re-education for post-SLAP debridement pain.

## Key findings

- LSN hydrodissection and physiotherapy resolved residual shoulder pain and restored strength in a patient.
- The patient returned to competitive arm wrestling and won a local tournament four months post-treatment.
- The case suggests functional deficits, not structural issues, may cause persistent pain after SLAP surgery.

## Abstract

Superior labrum anterior to posterior (SLAP) lesions are frequently identified on magnetic resonance imaging (MRI), particularly in middle-aged patients, yet many remain incidental and asymptomatic. Arthroscopic debridement of type I lesions may provide symptomatic relief; however, unsatisfactory outcomes may occur in some patients. Residual anterior shoulder pain may not be fully attributed to structural pathology alone, indicating a potential contribution of functional deficits, such as dynamic anterior instability and subscapularis dysfunction.

We report the case of a right-handed male amateur arm wrestler in his 40s, who presented with residual anterior shoulder pain (Numerical Rating Scale (NRS) score, 7) and internal rotation weakness (Manual Muscle Testing (MMT) grade, 3) following arthroscopic debridement of a type I SLAP lesion. Steroid injections and hydrodissection of the suprascapular and axillary nerves yielded limited benefits. Targeted ultrasound-guided hydrodissection of the lower subscapular nerve (LSN) was subsequently performed in combination with weekly physiotherapy, including ultrasound-guided subscapularis activation and manual neural mobilization. Pain improved immediately (NRS 3) and resolved within one month (NRS 0), with restoration of internal rotational strength (MMT 5). He resumed competitive arm wrestling four months postoperatively and subsequently won a local tournament.

Residual anterior shoulder pain after SLAP debridement may primarily reflect functional impairment, particularly subscapularis dysfunction, rather than residual labral pathology. Ultrasound-guided lower subscapular nerve (LSN) hydrodissection combined with subscapularis-specific rehabilitation is a promising therapeutic option for refractory postoperative anterior shoulder pain.