109. ARTHROSCOPIC BANKART BLOCK: FEASIBILITY AND REPRODUCIBILITY

Abstract

Purpose of the study: The purpose of this study was to determine the feasibility and reproducibility of a new arthroscopic procedure combining a Bristow-Latarjet lock with Bankart reinsertion of the lambrum.

Material and methods: Forty-seven consecutive patients with significant bone defects in the glenoid and a deficient capsule were treated arthroscopically: arthroscopic Bankart had failed in six. The procedure was performed exclusively arthroscopically using a special instrumentation: after its osteotomy and identification of the axiallary nerve, the coracoids was passed through the subcapular muscle with its tendon; the block was fixed on the scapular neck after 90° lateral rotation so as to prolong the natural concavity of the glenoid. Anchors and sutures were then used to refix the capsule and the labrum onto the glenoid border, leaving the block in an extra-articular position. Follow-up included a physical examination and standard x-rays at 45, 90 and 180 days; 31 patients had a postoperative scan. Three independent operators read the images.

Results: The procedure was completed arthroscopically in 41 of 47 patients (8%); conversion to a deltopectoral approach was required for six patients (12%). The axillary nerve was successfully identified in all shoulders. The block had a subequatorial position in 98% (46/47 shoulders) and equatorial in one. The block was tangent to the surface of the glenoid in 92% (43/47), lateral in one (2%) and too medial (> 5mm) in three (6%). One patient presented an early fracture of the block and five patients exhibited block migration; there was a partial lysis of the block in two patients. The final rate of nonunion of the block was 13% (6/47). Fractures, migrations and non-unions were related to technical errors: screws too short (unicortical) and/or poorly centred in the block.

Conclusion: Our results show that arthroscopic transfer of the coracoids to the scapular neck is a safe and successful operation. The rate of correctly positioned healed blocks was equivalent or superior to conventional techniques. The complications observed show that the arthroscopic block technique is difficult with a long learning curve.