ARTHROPATHY IN PATIENTS WITH MASSIVE ROTATOR CUFF TEARS: MORPHOLOGICAL ASPECTS AND THERAPEUTIC CONSEQUENCES

Abstract

Purpose: Preoperative morphology must be carefully assessed for proper surgical planning for patients with arthroplasty with massive rotator cuff tears, but many morphological aspects are poorly understood. The purpose of this study was to assess the technical implications of this situation.

Material and methods: We included patients with arthropathy with massive rotator cuff tears who had a complete clinical and radiographic preoperative work-up. We analysed the morphological aspects of the acromion, the humerus and the glenoid cavity.

Results: One hundred forty-two patients (148 shoulders) were included. The acromion presented a fracture or lysis in 13 shoulders and was thinned or had an imprint in 37. It was normal in 70 and hypertrophic in 16. The humerus showed signs of necrosis in 31 shoulders, with a washed out trochiter in 7. Glenoid wear was classed in four stages: E0 or normal glenoid (n=51), E1 or centred wear (n=32), E2 or biconcave aspect (n=46), and E3 or major wear with superior concavity (n=13). Inverted prostheses were implanted in 80 shoulders and non-constrained prostheses in 68. The non-constrained prostheses exhibited progressive ascension of the humeral head in 63% with wear of the glenoid vault. Clinical deterioration led to revision in two patients. The non-constrained prostheses inserted in patients with an E2 glenoid had a significantly lower Constant score (p< 0.05) than the others. A notch appeared in the scapular column in 65%; of the constrained prostheses. This notch was favoured significantly in glenoids classed E2 or E3 preoperatively. The preoperative aspect of the humerus did not appear to affect clinical and radiographic outcome.

Discussion: A thin or lysed acromion associated with an E2 glenoid constitutes a poor indication for non-constrained prosthesis. In this situation, an inverted prosthesis should be used taking care to avoid orienting the glenosphere upwardly, a technically difficult task. Good indications for non-contrained prostheses should probably be limited to shoulders with a normal or thickened acromion and and E1 glenoid.