Clapp Ian M, Braathen Dalton L, Blackburn Brenna E, Pelt Christopher E, Anderson Lucas A, Gililland Jeremy M, Archibeck Michael J
Department of Orthopaedic Surgery, University of Utah, Salt Lake City, Utah.
J Arthroplasty. 2025 Aug;40(8S1):S317-S321. doi: 10.1016/j.arth.2025.03.071. Epub 2025 Mar 31.
Currently, two-stage revision total hip arthroplasty is the gold standard in managing periprosthetic joint infection (PJI) of the hip; however, complications are common, including instability. The purpose of this study was to determine how alterations in limb length during a stage 1 articulating spacer affect dislocation rates of the stage 2 revision.
A retrospective study of consecutive patients who underwent two-stage revision total hip arthroplasty for PJI between December 2013 and December 2022 was performed. We measured limb length as the perpendicular distance from the trans-teardrop line to the apex of the lesser trochanter after stage 1 articulating spacer implantation. Independent t-tests and logistic regression were used to compare limb lengths following stage 1 spacers between patients who did and did not dislocate after stage 2 implantation. Overall, 147 patients who underwent staged revisions for the treatment of PJI were identified. The cohort was 59% women who had a mean age of 60 years (range, 25 to 84 years) and an average follow-up time of 2.7 years (range, 1.0 to 9.1 years).
The dislocation rates after stage 1 and stage 2 were 3.0 and 11.7%, respectively. Limb length did not impact dislocation rates of the articulating stage 1 spacers (P = 0.71), but patients who sustained a dislocation following stage 2 were lengthened significantly more at stage 1 implantation (8.5 ± 15.9 versus 0.8 ± 11.8 mm, P = 0.033). Additionally, the odds of dislocation after stage 2 increased by 7% with each mm lengthened during stage 1 (odds ratio = 1.07, 95% confidence interval: 1.01 to 1.13).
During a stage 1 articulating spacer of the hip, limb length restoration is often disregarded, which can result in overlengthening that may necessitate subsequent shortening during stage 2 reconstruction. This study demonstrates that overlengthening of an articulating stage 1 hip spacer can place the patient at an increased risk of dislocation following stage 2 reconstruction.
目前，两阶段翻修全髋关节置换术是治疗髋关节假体周围感染（PJI）的金标准；然而，并发症很常见，包括不稳定。本研究的目的是确定在一期使用活动型间隔器期间肢体长度的改变如何影响二期翻修的脱位率。
对2013年12月至2022年12月期间因PJI接受两阶段翻修全髋关节置换术的连续患者进行回顾性研究。我们将肢体长度测量为一期植入活动型间隔器后从泪滴线到小转子顶点的垂直距离。使用独立t检验和逻辑回归比较二期植入后脱位和未脱位患者一期间隔器植入后的肢体长度。总体而言，确定了147例接受分期翻修治疗PJI的患者。该队列中59%为女性，平均年龄60岁（范围25至84岁），平均随访时间2.7年（范围1.0至9.1年）。
一期和二期后的脱位率分别为3.0%和11.7%。肢体长度不影响一期活动型间隔器的脱位率（P = 0.71），但二期后发生脱位的患者在一期植入时肢体延长明显更多（8.5±15.9对0.8±11.8 mm，P = 0.033）。此外，一期每延长1 mm，二期后脱位的几率增加7%（优势比 = 1.07，95%置信区间：1.01至1.13）。
在髋关节一期使用活动型间隔器期间，肢体长度恢复常常被忽视，这可能导致过度延长，可能需要在二期重建时进行缩短。本研究表明，一期活动型髋关节间隔器过度延长会使患者在二期重建后脱位风险增加。
