[Shoulder arthrodesis with plate fixation. Special features in cases of resection and defects]

Shoulder arthrodesis following prosthesis explantation or resection of the acromion has not often been described in the literature. The presented article analyses the special features and problems of these preoperative circumstances in 4 cases and discusses them within the entire group.

Between 06/1987 and 02/2001, a total of 30 shoulder arthrodeses using plate fixation were performed in our clinic and then analysed after an average of 2.7 (0.5 - 8.7) years. Surgery was carried out on 5 (17 %) females and 25 (83 %) males with a mean age of 37 (17 - 82) years. Two patients underwent shoulder arthrodesis as a salvage operation following unsatisfactory arthroplasty, or after trapezius transfer with corresponding reduced bony conditions, respectively.

The active extent of movement following arthrodesis was 56 degrees (20 degrees - 90 degrees ) abduction, and 60 degrees (20 degrees - 105 degrees ) anteversion. The most frequent complications following arthrodesis included pseudarthroses (3/10 %), infections (4/13 %), and fractures of the humerus (4/13 %). The rate of complications was especially high in the cases after explantation of a shoulder prosthesis and resection of the acromion. In two of the four patients, three or five revision operations, respectively, were necessary. Two of the three pseudarthroses of the entire group occurred in these two cases.

Complications of shoulder arthrodesis after resection of the acromion or the proximal humerus are especially frequent. To avoid pseudarthrosis in such cases, primary spongioplasty is advantageous. A fixation with plates is superior to a simple screw arthrodesis. For postoperative immobilization a plaster cast instead of an orthotic device should be taken into consideration.