Purpose: Revision of a humeral prosthesis or a total shoulder arthroplasty is a difficult therapeutic challenge. The purpose of this work was to report our experience in a retrospective series of 19 inverted Grammont prostheses implanted during revision procedures.
Material and methods: The series included 11 women and eight men, mean age 66.8 years (45–84). Nine patients had already undergone at least two procedures before the revision of their prosthesis. There were 19 revisions of humeral prostheses and four revision total shoulder arthroplasties. Causes leading to revision of the humeral prostheses were: infection one patient, secondary cuff tears six patients, anterosuperior dislocation of the prosthesis five patients, and stiff and painful shoulders three patients. For the total shoulder arthroplasties, three required revision for a loosened glenoid implant and two for secondary cuff tears with ascension of the humeral head. The same access was used as for the first procedure in most of the cases (deltopectoral or anterolateral approach). The rotator cuff was torn and retracted, or fibrous and non-functional. Ablation of the humeral implant and the cement led to fracture (error or infection) in six cases requiring cerclage for fixation. A complementary bone graft was needed in three cases at the glenoid level in three and at the humeral level in three others.
Results: The Constant score at mean follow-up of 36.4 months (12–60) was 55.07 (44–87) a clear improvement over the initial 13.87 (6–39) before revision. The score was less favourable for patients with several operations before revision. Mean anterior elevation was 29.33° (20–100) pre-operatievely and reached 118.67° (90–160) postoperatively. The pain score was 3/15 preoperatively and13.66/15 postoperatively.
Discussion: Other alternatives may be indicated in salvage situations with an unreparable cuff and a pseudo-paralytic shoulder: rectus or deltoid flaps, reconstruction of the acro-miocoracoid arch and glenohumeral arthrodesis.
Conclusion: The inverted Grammont prosthesis appears to be a useful salvage technique, particularly when the acro-miocoracoid arch is destroyed and the cuff is unreparable. The best chances of success are observed for revision of hemiarthroplasties of a pseudo-paralytic shoulder with complete passive mobility and an anterosuperior dislocation of the humeral prosthesis head.
