Conjoint tendon split approach for humeral head extraction in acute anterior-to-inferior glenoid rim-incarceration fracture-dislocation and chronic locked anterior dislocation.

BACKGROUND: In acute anterior fracture-dislocation with humeral head incarceration at the anterior-to-inferior glenoid and in chronic locked anterior shoulder dislocation, the humeral head often lies immediately beneath the conjoint tendon, and a standard deltopectoral approach may provide insufficient working space for safe humeral head exposure and extraction. We evaluated the feasibility and neurologic safety of the conjoint tendon split approach (CSA) used as an adjunct for humeral head extraction in these challenging conditions. We hypothesized that CSA would facilitate humeral head extraction under direct visualization without increasing the risk of new postoperative musculocutaneous or axillary nerve deficits.

METHODS: This single-center retrospective case series included 11 consecutive patients (11 shoulders) in whom CSA was used as an adjunct for humeral head extraction and who had ≥6 months of follow-up. Patients were classified as acute (within 3 weeks with bony incarceration of the humeral head or head fragment at the anterior-to-inferior glenoid on computed tomography) or chronic (≥3 weeks with locked, functionally irreducible anterior dislocation because of scarring and capsular contracture). Primary outcomes were feasibility (successful humeral head extraction using CSA) and neurologic safety (new musculocutaneous or axillary nerve deficits at final follow-up). Data are reported as median (range) or number (percentage).

RESULTS: The median age was 84 years (59-88), 10 patients were female (90.9%), and median body mass index was 23.0 kg/m2 (20.4-31.6). Eight shoulders were acute and 3 were chronic. Reverse total shoulder arthroplasty was performed in 9 shoulders (81.8%) and hemiarthroplasty in 2 (18.2%). Pre-operative neurologic palsy was present in 2 patients (18.2%) (axillary nerve, n = 1; radial nerve, n = 1), with no musculocutaneous nerve palsy; both resolved during follow-up. CSA enabled successful humeral head exposure, mobilization, and extraction in all cases (feasibility, 100%). Median final follow-up was 13 months (6-36), and no new post-operative musculocutaneous or axillary nerve deficits infections, or early implant-related complications were observed.

CONCLUSION: In this series, CSA provided reliable access for humeral head extraction in acute anterior-to-inferior glenoid incarceration fracture-dislocation and chronic locked anterior dislocation, without new musculocutaneous or axillary nerve deficits.