Reiner Tobias, Sonntag Robert, Kretzer Jan Philippe, Clarius Michael, Jakubowitz Eike, Weiss Stefan, Kinkel Stefan, Walker Tilman, Gotterbarm Tobias, Nees Timo Albert
Department of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstraße 200a, Heidelberg, 69118, Germany.
Department of Orthopaedics, Laboratory of Biomechanics and Implant Research, Heidelberg University Hospital, Schlierbacher Landstr. 200a, Heidelberg, 69118, Germany.
Arthroplasty. 2025 Feb 4;7(1):7. doi: 10.1186/s42836-024-00290-y.
High-offset stems in cementless primary total hip arthroplasty (THA) have been potentially associated with early aseptic femoral loosening. This study aimed to evaluate the primary and secondary stability of a cementless high-offset femoral component under full weight-bearing conditions using model-based RSA, comparing it with a standard offset stem in patients undergoing THA.
In this prospective, observational, single-center study, 42 patients with end-stage hip osteoarthritis underwent cementless primary THA using either a standard (SL-PLUS Standard) or a high-offset (SL-PLUS Lateral) cementless stem. Radiostereometric analysis (RSA) was employed to monitor stem migration at six weeks and three, six, twelve, and twenty-four months. Clinical outcomes were assessed using the modified Harris Hip Score (HHS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).
There were no significant differences in mean stem subsidence between the groups at any follow-up interval, indicating comparable primary and secondary stability. After minimal initial subsidence (SL-PLUS Standard: up to -0.54 mm; SL-PLUS Lateral: up to -0.73 mm), no further progressive migration was observed. A significant difference in stem anteversion was noted between the groups at six months (P = 0.021) and two years (P = 0.001). The SL-PLUS Lateral group had significantly better WOMAC scores at the two-year follow-up (P = 0.027).
This RSA study demonstrated similar migration patterns for the high-offset and standard-offset cementless stems within the first two years after operation. Both groups exhibited initial subsidence followed by high secondary stability. Based on the results of this study, the SL-PLUS Lateral is a safe alternative for patients with high femoral offset undergoing cementless THA.
在非骨水泥型初次全髋关节置换术（THA）中，高偏心距股骨柄可能与早期无菌性股骨柄松动有关。本研究旨在使用基于模型的RSA评估非骨水泥型高偏心距股骨组件在全负重条件下的初次和二次稳定性，并将其与接受THA的患者使用的标准偏心距股骨柄进行比较。
在这项前瞻性、观察性、单中心研究中，42例终末期髋骨关节炎患者接受了非骨水泥型初次THA，使用标准（SL-PLUS Standard）或高偏心距（SL-PLUS Lateral）非骨水泥股骨柄。采用放射立体测量分析（RSA）在六周以及三、六、十二和二十四个月时监测股骨柄的移位情况。使用改良Harris髋关节评分（HHS）和西安大略和麦克马斯特大学骨关节炎指数（WOMAC）评估临床结果。
在任何随访间隔中，两组之间的平均股骨柄下沉均无显著差异，表明初次和二次稳定性相当。在最小初始下沉后（SL-PLUS Standard：高达-0.54 mm；SL-PLUS Lateral：高达-0.73 mm），未观察到进一步的渐进性移位。两组在六个月（P = 0.021）和两年（P = 0.001）时股骨柄前倾角存在显著差异。在两年随访时，SL-PLUS Lateral组的WOMAC评分显著更好（P = 0.027）。
这项RSA研究表明，高偏心距和标准偏心距非骨水泥股骨柄在术后两年内具有相似的移位模式。两组均表现出初始下沉，随后具有较高的二次稳定性。基于本研究结果，SL-PLUS Lateral对于接受非骨水泥型THA的高股骨偏心距患者是一种安全的选择。
