Anderson Thomas, Montgomery Fredrik, Carlsson Ake
Department of Orthopaedics, Malmö University Hospital, Malmö SE-205 02, Sweden.
J Bone Joint Surg Am. 2004 Sep;86-A Suppl 1(Pt 2):103-11. doi: 10.2106/00004623-200409001-00001.
The feasibility of replacing the ankle joint has been a matter of speculation for a long time. In recent years, the designs of ankle prostheses have been improved, and three designs, all used without bone cement, currently dominate the market. However, documentation of the clinical results of the use of these prostheses is sparse. We reviewed the intermediate-term results of fifty-one consecutive Scandinavian Total Ankle Replacements (STAR).
Between 1993 and 1999, fifty-one consecutive ankles were replaced with an uncemented, hydroxyapatite-coated STAR total ankle prosthesis. Clinical examination for the present study was performed by one surgeon who had not taken part in the operations. Standardized radiographs were used. Complications and failures were recorded, and patient satisfaction and functional outcome scores were determined for all patients with an unrevised implant.
Twelve ankles had to be revised. Seven were revised because of loosening of at least one of the components; two, because of fracture of the meniscus; and three, for other reasons. A component was exchanged in seven of the twelve revisions, whereas the ankle was successfully fused in the other five. An additional eight ankles had radiographic signs of loosening. The thirty-nine unrevised ankles (thirty-seven patients) were examined after thirty-six to ninety-seven months (median, fifty-two months). The patient was satisfied with the result after thirty-one of the ankle replacements, somewhat satisfied after two, and not satisfied after six. The median Kofoed score increased from 39 points before the surgery to 70 points at the time of the follow-up examination. A median follow-up score of 74 points was recorded when the system described by Mazur et al. and the AOFAS (American Orthopaedic Foot and Ankle Society) system were used. The median range of motion was approximately the same preoperatively and postoperatively. The estimated five-year survival rate, with revision for any reason as the end point, was 0.70. When radiographic loosening of either component was used as the end point, the estimated five-year radiographic survival rate was significantly better for the last thirty-one ankles treated in the series (p = 0.032).
Total ankle replacement may be a realistic alternative to arthrodesis, provided that the components are correctly positioned and are of the correct size. However, the risks of loosening and failure are still higher than are such risks after total hip or total knee replacement.
长期以来，踝关节置换的可行性一直是个备受猜测的问题。近年来，踝关节假体的设计有所改进，目前市场上占主导地位的有三种设计，均为非骨水泥型。然而，关于这些假体使用的临床结果的文献资料却很稀少。我们回顾了连续51例斯堪的纳维亚全踝关节置换术（STAR）的中期结果。
1993年至1999年期间，连续51例踝关节采用非骨水泥型、羟基磷灰石涂层的STAR全踝关节假体进行置换。本研究的临床检查由一名未参与手术的外科医生进行。使用标准化的X线片。记录并发症和失败情况，并确定所有未翻修假体患者的患者满意度和功能结果评分。
12例踝关节需要翻修。7例因至少一个组件松动而翻修；2例因半月板骨折；3例因其他原因。12例翻修中有7例更换了组件，另外5例踝关节成功融合。另有8例踝关节有X线松动迹象。对39例未翻修的踝关节（37例患者）在术后36至97个月（中位数为52个月）进行了检查。31例踝关节置换术后患者对结果满意，2例有点满意，6例不满意。Kofoed评分中位数从术前的39分提高到随访时的70分。当使用Mazur等人描述的系统和美国矫形足踝协会（AOFAS）系统时，随访评分中位数为74分。术前和术后的活动范围中位数大致相同。以任何原因进行翻修为终点的估计五年生存率为0.70。当以任何一个组件的X线松动为终点时，该系列中最后治疗的31例踝关节的估计五年X线生存率明显更好（p = 0.032）。
全踝关节置换术可能是关节融合术的一个现实替代方案，前提是组件正确定位且尺寸合适。然而，松动和失败的风险仍然高于全髋关节或全膝关节置换术后的此类风险。
