How do we treat severe knee OA with bowing deformity of tibia after malunion. Correction osteotomy with TKA was usually performed. However, there were risks of severe several complications. This is a case report of the patient received TKA didn't accept the risks of correction osteotomy. 74 year-old- lady consulted our clinic with chief complains of left knee pain and disability of walking. Her left knee pain began 20 years ago without any episodes. Her walking ability getting worse gradually in these 5 months. However, she have been received conservative treatment. She suffered left tibia fracture and received ORIF at age 21. Her course of after the surgery was not satisfied with infection. Finally her tibia achieved union. However, her tibia demonstrated bowing and shortening with varus deformity. Her knee joint also demonstrated varus deformity with ROM 95(ext. −20, flex. 115). There were pressure pain at the medial joint space, demonstrated varus-valgus instability. Roentgenograms showed severe OA with defect of medial tibial condyle (Fig.1) and malunion of the tibia with bowing deformity. Mechanical FTA angle was 151 degrees (Fig.2). Deformity angle of the malunion tibia was 25 degrees. Severe knee OA with tibia deformity was indication of TKA with correction tibial osteotomy. We proposed TKA with correction tibial osteotomy for her. We also explain risks and benefits of the surgery for her. She didn't want osteotomy for risks of infection and non-union, she decided that she receive only TKA. We planned TKA with tibial extension stem and fix with tilting position in the tibia shaft using bone cement. TKA was performed the same as planning (Fig.3). Her leg alignment corrected good position with ROM 125 (ext. 0, flex. 125) at follow-up. It was recommended that TKA for severe deformity without correction osteotomy is generally performed under 20 degrees of the correction angle. Our case was out of indication for this point of view. However, precise check of the pre-surgical roentgenograms could get solution of the difficult surgery. We are thinking of longevity of the implants because of unexpected stress, so we should need long follow–up of this case.
It is very difficult to perform total knee arthroplasty (TKA) for severe varus bowing deformity of femur. We performed simultaneous combined femoral supra-condyle valgus osteotomy and TKA for the case had bilateral varus knees with bowing deformity of femurs. A 62-year-old woman consulted our clinic with bilateral knee pain and walking distability. She was diagnosed rickets and had bilateral severe varus bowing deformity of femurs from an infant. Her height was 133 cm and body weight was 51 kg. Bilateral femur demonstrated severe bowing and her knee joint demonstrated varus deformity with medial joint line tenderness, no local heat, and no joint effusion. Bilateral knee ROM was 90 degrees with motion crepitus. Bilateral lower leg demonstrated mild internal rotation deformity. Bilateral JOA knee score was 40 Roentgenogram demonstrated knee osteoarthritis with incomplete development of femoral condyle. Mechanical FTA angles were 206 degree on the right and 201 on the left. She was received right simultaneous femoral supra-condyle valgus osteotomy with TKA was performed at age 63. Key points of surgical techniques were to use the intramedullary guide for valgus osteotomy as temporary reduction and fixation then performed mono-cortical locking plate fixation. Several mono cortical screws were exchanged to bi-cortical screws after implantation of the femoral component with long stem. Cast fixation performed during two weeks and full weight bearing permitted at 7 weeks after surgery. Her JOA score was slightly improved 50 due to other knee problems at 9 months after surgery, her right mechanical FTA was decreased to 173, and she received left simultaneous femoral supra-condyle valgus osteotomy with TKA as the same technique at April of this year. She has been receiving rehabilitation at now. Most causes of varus knee deformity are defect or deformity of medial tibial condyle and TKA for theses cases are not difficult to use tibial augment devices. However the cases like our presentation need supra-femoral condyle osteotomy before TKA. It was easy and useful to use intramedullary guide for valgus osteotomy as temporary reduction and fixation then performed mono-cortical locking plate fixation before TKA.Case presentation
Conclusions
Many TKA instruments were developed in these days. Distal femoral cutting guide using intra-medullary system were divided into two methods, from anterior or medial. Many companies employed anterior cutting guide, however these guides have a disadvantage of wide skin and quadriceps incision. Only Zimmer provided medial cut guide which performed short skin and quadriceps incision. However, reference point (medial femoral condyle) will be a risk of imprecise cutting for a medial condyle defect cases. We tried L-shaped new distal femoral cutting guide, reference point will be both femoral condyle and cutting from antero-medial side. The purpose of this study was to prove usefulness of the new guide. Twenty-nine knees were employed in this study. All knees were treated with Optetrak knee system (Exactec). Surgical methods were as follows, mid line skin incision, short para-patellar deep incision, no patellar resurfacing, PS type implant and cement fixation were employed. 13 knees were used original anterior cutting guide (O group) and 16 knees were used new antero-medial cut guide (N group). Study items were length of skin incision, length of Quadriceps incision, surgical time, JOA score, and component tilting angles (implant position were compared to femoral axis with AP and lateral view of roentgenograms).Purpose
Materials and Methods