Abstract：
OBJECTIVE: This study aimed (1) to determine complications and survival rates of lateral opening wedge distal femoral osteotomy (LOW-DFO) in the long term, (2) to assess their clinical outcomes in the long term and (3) to identify risk factors of failure.
METHODS: Between 1991 and 2011, 62 LOW-DFOs were performed in the same department. Inclusion criteria were all isolated LOW-DFO performed for isolated lateral tibiofemoral osteoarthritis and valgus malalignment, with a minimum 10-year follow-up. Thirty-eight patients were included, with a mean age of 48 ± 9 years. All patients had clinical and radiological assessments. The survival curves were calculated based on the following endpoints: unicompartmental or total knee arthroplasty.
RESULTS: The mean follow-up was 15.2 ± 4.4 [10-29] years. The mean preoperative mechanical FemoroTibial Axis (mFTA) was 188.8° ± 3.2° [184°-197°], primarily due to femur deformity (mean lateral distal femoral axis [LDFA] 83.2° ± 2.8°). Bone union was achieved in 89.5% of patients (n = 34) at a mean delay of 6.5 ± 6.7 months. The complication rate was 26% (five stiffness, one nonunion, three secondary displacements and one deep vein thrombosis). Nine revision surgeries (24%) were recorded. Survival rates at 5 and 10 years were 92.1% and 78.9%, respectively. The mean delay between DFO and total knee arthroplasty (TKA) was 11.6 ± 5.7 [1-27] years. Nineteen patients (50%) were free of TKA at the last follow-up. KSS scores were improved significantly. Return to sports was obtained in 92% of cases (n = 35), with a mean delay of 11 ± 8 months. Seventy-four per cent of patients were satisfied or very satisfied with the surgery. Eighty-four per cent would be willing to undergo the surgery again. Older age (p = 0.032) was a significant risk factor for TKA conversion.
CONCLUSIONS: LOW-DFO is an efficient procedure to manage lateral knee osteoarthritis in young patients with valgus deformity, with a good survival rate at 10 years and high patient satisfaction.
METHODS: Level III.
METHODS: Between 1991 and 2011, 62 LOW-DFOs were performed in the same department. Inclusion criteria were all isolated LOW-DFO performed for isolated lateral tibiofemoral osteoarthritis and valgus malalignment, with a minimum 10-year follow-up. Thirty-eight patients were included, with a mean age of 48 ± 9 years. All patients had clinical and radiological assessments. The survival curves were calculated based on the following endpoints: unicompartmental or total knee arthroplasty.
RESULTS: The mean follow-up was 15.2 ± 4.4 [10-29] years. The mean preoperative mechanical FemoroTibial Axis (mFTA) was 188.8° ± 3.2° [184°-197°], primarily due to femur deformity (mean lateral distal femoral axis [LDFA] 83.2° ± 2.8°). Bone union was achieved in 89.5% of patients (n = 34) at a mean delay of 6.5 ± 6.7 months. The complication rate was 26% (five stiffness, one nonunion, three secondary displacements and one deep vein thrombosis). Nine revision surgeries (24%) were recorded. Survival rates at 5 and 10 years were 92.1% and 78.9%, respectively. The mean delay between DFO and total knee arthroplasty (TKA) was 11.6 ± 5.7 [1-27] years. Nineteen patients (50%) were free of TKA at the last follow-up. KSS scores were improved significantly. Return to sports was obtained in 92% of cases (n = 35), with a mean delay of 11 ± 8 months. Seventy-four per cent of patients were satisfied or very satisfied with the surgery. Eighty-four per cent would be willing to undergo the surgery again. Older age (p = 0.032) was a significant risk factor for TKA conversion.
CONCLUSIONS: LOW-DFO is an efficient procedure to manage lateral knee osteoarthritis in young patients with valgus deformity, with a good survival rate at 10 years and high patient satisfaction.
METHODS: Level III.
摘要：
目的：本研究旨在（1）确定外侧开放楔形股骨远端截骨术（LOW-DFO）的长期并发症和生存率，（2）评估其长期临床结果；（3）确定失败的危险因素。
方法：在1991年至2011年之间，在同一部门进行了62次LOW-DFO。纳入标准为所有分离的LOW-DFO，用于分离的胫骨外侧骨性关节炎和外翻畸形，至少10年随访。包括38名患者，平均年龄为48±9岁。所有患者均进行了临床和放射学评估。根据以下终点计算存活曲线：单室或全膝关节置换术。
结果：平均随访时间为15.2±4.4[10-29]年。术前平均机械股骨胫骨轴（mFTA）为188.8°±3.2°[184°-197°]，主要是由于股骨畸形（平均外侧股骨轴[LDFA]83.2°±2.8°）。在平均延迟6.5±6.7个月时，89.5％的患者（n=34）实现了骨愈合。并发症发生率为26%（五僵硬，一个骨不连,三次二次移位和一次深静脉血栓形成)。记录了9次修正手术（24％）。5年和10年生存率分别为92.1％和78.9％，分别。DFO和全膝关节置换术（TKA）之间的平均延迟为11.6±5.7[1-27]年。19例患者（50％）在最后一次随访中没有TKA。KSS评分显著提高。92%的病例(n=35)恢复了运动，平均延迟11±8个月。74％的患者对手术感到满意或非常满意。84％的人愿意再次接受手术。年龄较大（p=0.032）是TKA转换的重要危险因素。
结论：LOW-DFO是治疗年轻外翻畸形患者膝关节外侧骨关节炎的有效方法，10年生存率高，患者满意度高。
方法：三级。
方法：在1991年至2011年之间，在同一部门进行了62次LOW-DFO。纳入标准为所有分离的LOW-DFO，用于分离的胫骨外侧骨性关节炎和外翻畸形，至少10年随访。包括38名患者，平均年龄为48±9岁。所有患者均进行了临床和放射学评估。根据以下终点计算存活曲线：单室或全膝关节置换术。
结果：平均随访时间为15.2±4.4[10-29]年。术前平均机械股骨胫骨轴（mFTA）为188.8°±3.2°[184°-197°]，主要是由于股骨畸形（平均外侧股骨轴[LDFA]83.2°±2.8°）。在平均延迟6.5±6.7个月时，89.5％的患者（n=34）实现了骨愈合。并发症发生率为26%（五僵硬，一个骨不连,三次二次移位和一次深静脉血栓形成)。记录了9次修正手术（24％）。5年和10年生存率分别为92.1％和78.9％，分别。DFO和全膝关节置换术（TKA）之间的平均延迟为11.6±5.7[1-27]年。19例患者（50％）在最后一次随访中没有TKA。KSS评分显著提高。92%的病例(n=35)恢复了运动，平均延迟11±8个月。74％的患者对手术感到满意或非常满意。84％的人愿意再次接受手术。年龄较大（p=0.032）是TKA转换的重要危险因素。
结论：LOW-DFO是治疗年轻外翻畸形患者膝关节外侧骨关节炎的有效方法，10年生存率高，患者满意度高。
方法：三级。
