[Hip joint arthrodesis using the cobra plate. Indication, technique, outcome].

In the era of successful total hip replacement, hip arthrodesis has become an infrequent surgical procedure. Current indications are severe deterioration of the hip joint with a painful, reduced range of motion in young patients, such as disorders subsequent to sepsis of the hip joint, slipped capital epiphysis, Perthes' disease and trauma with contraindications for a total joint replacement. Another important indication is paralysis or musculature loss. From 1980 to 1990, 20 consecutive patients underwent a hip arthrodesis with a cobra plate and were evaluated. None of the patients was lost for follow-up; complications occurred in 5 out of 25 cases (20%). All patients had radiographic evidence of union, 2 patients required re-osteosynthesis and bone grafting. In two cases infection occurred. In one case the position of the fused join went into abduction. Thirteen patients were able to walk free of pain; however, 5 patients were disappointed with the arthrodesis result because of the handicap involved with a fused hip. Hip arthrodesis using the cobra plate is a technically demanding operation, but immediate mobilization and partial weight bearing are facilitated. There is little risk of non-union compared to other surgical procedures. If the technique is correct functional problems will be rare.