THE TERRIBLE TRIAD OF THE SHOULDER

Abstract

To review the outcome of compound injury to the shoulder in which traumatic anterior dislocation is associated with concomitant rotator cuff tear and injury to the brachial plexus.

22 patients initially treated at the Peripheral Nerve Injury Unit since 1994 were reviewed from notes, telephone and clinically (n=13) where possible. 19 men and 3 women of average age 53 years were treated with a minimum 3-year follow up. All patients underwent exploration of the brachial plexus and nerve repair where required (graft n=5). Patients had either proven large cuff tear (n=13) or avulsion fracture of greater tuberosity with cuff injury (n=9). 7 of 13 cuff injuries and 7 of 9 tuberosity fractures had been repaired. Nerve injury at exploration was to circumflex (n=20), supra-scapular (n=12), musculocutaneous (n=6), or at the cord level (Posterior n=10, Lateral n=7 Medial n=8). Outcome measures were Berman pain score, sensation, muscle power (MRC grade), abduction, functional scores (Mallett and DASH) and return to work. Statistical analysis used tests for non-parametric data.

22 patients had exploration of the plexus. Most patients did not have an isolated nerve lesion (n=4). Increased depth of nerve lesion correlated with poorer functional outcome. E.g. for circumflex nerve injury (n=18), conduction block (n=8) vs. axonotmesis or neurotmesis (n =10) functional range of movement as assessed by Mallett score was significantly different; Mann Whitney U test p=0.043. Late exploration of nerve tended to correlate with poor outcome, as did late repair of rotator cuff, but not to statistical significance.

Our explorations have shown the nerve injury sustained in these patients to be more widespread than expected. We believe early exploration is vital to give an accurate diagnosis and predict outcome for the nerve lesion. This is particularly important in the presence of associated cuff injury where early repair confers favourable outcome.