Dome osteotomy of the proximal tibia for genu varum treated with a new fixation device.

An innovative uniplanar-bilateral external fixator was designed, developed, and implemented for barrel-vault osteotomy of the proximal tibia. Eighteen cases of medial compartmental osteoarthritis of the knee with genu varum and one case of tibia vara were treated with dome osteotomy fixed with this new fixator to meet patient expectations regarding pain relief, early recovery with ability to squat, dependency periods, avoiding serious complications, convenience, and economic conditions. All cases achieved the desired degree of bony correction except for one case with 5 degrees undercorrection due to preoperative posterolateral corner laxity. Plaster immobilization was not required during the treatment period, and all osteotomies united within 6-10 weeks with no major complications. Superficial pin tract infection occurred in three cases. All patients returned to their activities of daily living by postoperative week 2. The Knee Society Score was 75-100 with average function/knee scores of 88.89/96.32 by the end of 2 months. Patients maintained these scores up to 2-year follow-up. This new fixator is compact and economical, with excellent patient compliance. It provides a stable fixation for the osteotomy and permits early joint mobilization, full weight bearing, and early return to activities of daily living. The fixator has the ability to alter correction in the early postoperative period to achieve a precise correction of the deformity. It qualifies as a safe device for this procedure, produces reliable and reproducible results, as well as satisfies patient expectations.