Supracondylar femoral dome extension osteotomy in treatment of knee flexion deformity

Abstract

Background Flexion contracture of the knee can happen by different etiologies such as burns and scars, inflammatory conditions such as juvenile rheumatoid arthritis, and neuromuscular disorders such as cerebral palsy, poliomyelitis, and many others. Supracondylar femoral extension osteotomy is widely used in treatment of such type of deformities with good results. Dome osteotomy is a circular-shaped osteotomy. The authors conducted this study to assess the effectiveness of supracondylar femoral dome extension osteotomy (SCDEO) in management of sagital plane deformity in the form of fixed-flexion deformity of the knee. Patients and methods Seven patients (11 knees) with knee flexion deformity underwent SCDEO fixed by anatomical locked plate and screws, three patients had a bilateral deformity as sequelae of juvenile rheumatoid arthritis, while four patients as sequelae of poliomyelitis, and three of them had unilateral deformity, while only one patient had bilateral deformity. The knee flexion deformity angle ranged from 20 to 50° with a mean of 32°. Patients were followed up every 2 weeks with monthly radiographies done till full union of the osteotomy, full weight bearing was started at 4 weeks postoperatively, in bilateral cases, the other side was operated after full osteotomy union, and all patients were followed up for 12 months with radiographies to assess the knee flexion deformity angle. Results All osteotomies eventually united in the period ranging from 10 to 14 weeks (average 12 weeks), no postoperative infection, nonunion, neurological, or vascular compromise occurred. All of the patients were satisfied regarding improved gait and posture, the total range of knee motion at 12 months postoperatively ranged from 60 to 100° (average 85°). Knee flexion deformity angle measured at 12 months postoperatively ranged from 8 to 15° with an average of 11°. Only one patient with juvenile rheumatoid arthritis showed significant recurrence of the deformity at 12 months of follow-up postoperatively, with flexion deformity angles of 20 and 25° in the right and left knee, respectively, whereas the preoperative flexion deformity angle in this patient was 30 and 35° in the right and left knee, respectively. Conclusion SCDEO fixed by anatomical locked plate and screws is an effective means of management of knee fixed-flexion deformity.