Supracondylar dome osteotomy for cubitus valgus deformity associated with a lateral condylar nonunion in children. Surgical technique.

BACKGROUND: Open reduction, autogenous bone-grafting, and internal fixation for the treatment of established nonunion of the lateral condyle associated with a cubitus valgus deformity has a high rate of complications. As a consequence, we developed a new technique that includes in situ compression fixation of the lateral condylar nonunion and a dome-shaped supracondylar osteotomy of the distal aspect of the humerus through a single posterior incision.

METHODS: Eight consecutive patients were treated with the new surgical technique between 1994 and 2000. The mean age at the time of surgery was 8.6 years. The mean interval between the lateral condylar fracture and surgery was 4.9 years. The mean preoperative radiographic humerus-ulna angle was 31 degrees of valgus. The postoperative results were classified with a modification of the scoring system described by Dhillon et al., which assesses pain, weakness, range of motion, the humerus-ulna angle, and prominence of the medial epicondyle on a 12-point scale.

RESULTS: All eight lateral condylar nonunions achieved union within three months postoperatively. The mean postoperative humerus-ulna angle was 5.5 degrees of valgus. All of the supracondylar dome osteotomies healed uneventfully, and there was no loss of correction postoperatively. The mean duration of follow-up was 4.5 years. The overall results were excellent in two patients, good in four patients, and fair in two patients.

CONCLUSIONS: With better exposure of the lateral condylar nonunion through a posterior approach, we can effectively stabilize the lateral condylar nonunion and avoid postoperative loss of motion and osteonecrosis of the condyle. With a dome-shaped supracondylar osteotomy, we can correct the cubitus valgus deformity and avoid the development of a medial epicondylar prominence. With careful selection of patients, this new technique can be an effective method to treat this clinically challenging problem.