Ortiguera Cedric J, Berry Daniel J
Department of Orthopedics, Mayo Clinic, Rochester, Minnesota 55905, USA.
J Bone Joint Surg Am. 2002 Apr;84(4):532-40. doi: 10.2106/00004623-200204000-00004.
Patellar fracture can occur as a complication following total knee arthroplasty. The purpose of this study was to evaluate a large series of patellar fractures to determine the results of different forms of treatment of specific fracture types.
A retrospective review identified eighty-five fractures (in seventy-seven patients) following 12,464 consecutive total knee arthroplasties performed between 1985 and 1998. Seventy-eight fractures occurred after primary total knee arthroplasty and seven, after revision total knee arthroplasty. Five fractures were treated elsewhere, and two others were lost to follow-up. The results of treatment of the remaining seventy-eight fractures were reviewed. Fractures were classified according to three main criteria: integrity of the extensor mechanism, fixation status of the patellar implant, and quality of the remaining bone stock. The mean duration of follow-up was 3.6 years.
The prevalence of patellar fracture after total knee arthroplasty was 0.68%; fractures were significantly more prevalent among men (1.01%) than among women (0.40%) (p = 0.0004). Thirty-eight fractured patellae had a stable implant and an intact extensor mechanism (Type I). All but one were treated nonoperatively, and there was only one late failure of nonoperative treatment, which required operative intervention. Twelve fractures were associated with disruption of the extensor mechanism (Type II). Eleven were treated operatively; six knees had complications and five had a reoperation. Twenty-eight fractures occurred in association with a loose patellar component (Type III). Twenty were treated operatively; nine knees had complications, and four had a reoperation.
Patellar fractures after total knee arthroplasty are infrequent. Treatment can be guided by three main criteria: integrity of the extensor mechanism, fixation status of the patellar implant, and quality of the remaining bone. Fractures associated with a stable implant and an intact extensor mechanism were usually treated successfully with nonoperative means, with minimal complications. When operative treatment was required, it was associated with a high rate of complications and reoperations.
髌骨骨折可能作为全膝关节置换术后的一种并发症出现。本研究的目的是评估一大系列髌骨骨折，以确定特定骨折类型的不同治疗方式的结果。
一项回顾性研究确定了1985年至1998年间连续进行的12464例全膝关节置换术后的85例骨折（77例患者）。78例骨折发生在初次全膝关节置换术后，7例发生在翻修全膝关节置换术后。5例骨折在其他地方接受治疗，另外2例失访。对其余78例骨折的治疗结果进行了回顾。骨折根据三个主要标准进行分类：伸膝装置的完整性、髌骨假体的固定状态以及剩余骨量的质量。平均随访时间为3.6年。
全膝关节置换术后髌骨骨折的发生率为0.68%；男性（1.01%）的骨折发生率显著高于女性（0.40%）（p = 0.0004）。38例髌骨骨折的假体稳定且伸膝装置完整（I型）。除1例之外均采用非手术治疗，非手术治疗仅有1例出现晚期失败，需要手术干预。12例骨折与伸膝装置断裂有关（II型）。11例接受了手术治疗；6例膝关节出现并发症，5例进行了再次手术。28例骨折与髌骨假体松动有关（III型）。20例接受了手术治疗；9例膝关节出现并发症，4例进行了再次手术。
全膝关节置换术后的髌骨骨折并不常见。治疗可依据三个主要标准进行指导：伸膝装置的完整性、髌骨假体的固定状态以及剩余骨的质量。与稳定的假体和完整的伸膝装置相关的骨折通常采用非手术方法成功治疗，并发症最少。当需要手术治疗时，其并发症和再次手术的发生率较高。
