The Department of Orthopedics Surgery, Ningbo No. 6 Hospital, Ningbo, Zhejiang, People's Republic of China.
Medicine (Baltimore). 2022 Mar 18;101(11). doi: 10.1097/MD.0000000000029056.
Pseudotumor formation after hip arthroplasty is a rare complication that can occur not only at the head-neck junction but also at the modular neck-stem junction. Dislocation is a challenging and common complication of primary and revision total hip arthroplasty compared with other complications. Similarly, the association between pseudotumors and delayed recurrent dislocation remains unclear.
We report the case of a 73-year-old woman with pseudotumor formation after total hip arthroplasty combined with a modular femoral neck. A delayed recurrent dislocation occurred in this case. Approximately 4weeks after the first revision surgery, redislocation occurred.
The patient was eventually diagnosed with delayed recurrent artificial hip dislocation combined with a periprosthetic pseudotumor of the right hip.
During the first revision surgery, a thickened, indurated cyst measuring 8×3×8cm with a red-brown wall containing brown fluid was completely excised. A cemented stem, combined with a BIOLOX Forte ceramic head, was implanted. Approximately 4weeks after surgery, redislocation occurred, and we cemented an elevated rim liner on the acetabular component with a metal head.
At the last follow-up, 49 months after revision surgery, the patient was asymptomatic with a Harris hip score of 90. The patient had a satisfactory prognosis after treatment.
The application of the modular-neck stem should be cautiously performed, particularly for modular prostheses containing different alloys. Pseudotumors and insufficient soft-tissue tension both contribute to hip instability, which may eventually lead to delayed repeated dislocation. In addition, femoral offset must be considered. Cement-liner technology may be used for aging patients who are less active. This case report, focusing on pseudotumors and delayed recurrent dislocations, aimed to identify factors that may support this diagnosis, which is easy to miss. Consequently, it can provide further details on the treatment process and alert orthopedic surgeons to this infrequent but important cause of delayed recurrent dislocation.
髋关节置换术后假性肿瘤的形成是一种罕见的并发症，不仅可发生在头颈交界处，也可发生在模块化颈干交界处。与其他并发症相比，脱位是初次和翻修全髋关节置换术的一种具有挑战性且常见的并发症。同样，假性肿瘤与迟发性复发性脱位之间的关系尚不清楚。
我们报告了一例 73 岁女性，在全髋关节置换术后合并模块化股骨颈假性肿瘤。该病例发生迟发性复发性脱位。第一次翻修手术后约 4 周，再次发生脱位。最终诊断为右侧人工髋关节迟发性复发性脱位合并髋关节周围假性肿瘤。第一次翻修手术时，完全切除了一个 8×3×8cm 厚、质地坚硬的囊肿，囊壁呈红棕色，内含棕色液体。植入了一个带 BIOLOX Forte 陶瓷头的水泥固定柄。手术后约 4 周，再次发生脱位，我们在髋臼组件上用金属头固定了一个升高的边缘衬垫。
翻修手术后 49 个月的最后一次随访时，患者无症状，髋关节 Harris 评分为 90 分。治疗后患者预后良好。
应谨慎应用模块化颈干，特别是对于含有不同合金的模块化假体。假性肿瘤和软组织张力不足都可导致髋关节不稳定，最终可能导致迟发性反复脱位。此外，还必须考虑股骨偏心距。对于活动量较少的老年患者，可使用水泥衬垫技术。本病例报告重点关注假性肿瘤和迟发性复发性脱位，旨在确定可能支持这一诊断的因素，因为这一诊断容易被忽视。因此，它可以提供关于治疗过程的更多细节，并提醒骨科医生注意这种不常见但重要的迟发性复发性脱位原因。
