Universitätsklinikum Augsburg, Klinik für Unfallchirurgie, Orthopädie, Plastische und Handchirurgie, Stenglinstraße 2, 86156, Augsburg, Deutschland.
München Klinik Neuperlach, Oskar-Maria-Graf-Ring 51, 81737, München, Deutschland.
J Orthop Traumatol. 2023 Nov 9;24(1):58. doi: 10.1186/s10195-023-00738-y.
The aim of this study is a clinical evaluation of the center of rotation (COR) placement towards a patient's recovery with respect to daily living ability and mobility. In past experiments based on three-dimensional (3D) models, medialization of the COR in total hip arthroplasty (THA) showed a negative influence on muscle strength of the abductors and reaction force of the hip joint. This contradicts paradigms, where reduced hip loading forces are claimed to increase functional outcomes.
The plain X-rays of 110 patients who underwent THA after a femoral neck fracture between January 2019 and January 2021 were retrospectively evaluated. A Barthel Index on discharge was obtained in 69 cases. 47 patients were available for a follow-up interview concerning the Barthel Index, Parker mobility score (PMS), and pain levels (NRS) 6 and 12 months after surgery.
Medialization of the COR had a significantly negative effect on the need for care (Barthel Index) at patient discharge (Spearman correlation 0.357, p = 0.013). The effect on the PMS is still existent at 6 and 12 months (Spearman correlation 0.471, p = 0.009 at 6 months; 0.472, p = 0.008 at 12 months). Mann-Whitney U tests showed that the groups with medialized COR performed significantly worse than the lateralized groups. This was seen for the Barthel Index at discharge and at 6 months after surgery and for the PMS at 6 and 12 months. The accurately reconstructed CORs showed no significant differences from the lateralized rotation centers in need of care and mobility. The superior COR placement group showed significantly reduced mobility at 12 months in contrast to the inferior COR placement group (p = 0.008), and the group of accurately reconstructed rotation centers showed significantly less pain than the inferior COR placement group (p = 0.007 after 6 months, p = 0.026 after 12 months). Especially the combination of both (superomedialization) leads to reduced mobility (Spearman correlation 0.67, p = < 0.001).
COR superior displacement, COR medialization, and the combination of both (superomedialization, Spearman p = < 0.001) lead to reduced mobility while inferior displacement showed increased pain. According to our results, we recommend an exact vertical COR restoration, while horizontal medial displacement needs to be avoided.
III.
本研究旨在通过临床评估旋转中心（COR）的位置，探讨其对患者日常生活能力和活动能力恢复的影响。在过去基于三维（3D）模型的实验中，全髋关节置换术（THA）中 COR 的内侧化对髋关节外展肌的肌力和髋关节的反作用力有负面影响。这与减少髋关节负荷力会增加功能结果的理论相悖。
回顾性分析了 2019 年 1 月至 2021 年 1 月期间因股骨颈骨折接受 THA 的 110 例患者的普通 X 射线。69 例患者在出院时获得巴氏指数。47 例患者在术后 6 个月和 12 个月接受随访，评估巴氏指数、帕克移动评分（PMS）和疼痛水平（NRS）。
COR 的内侧化对患者出院时的护理需求（巴氏指数）有显著的负面影响（Spearman 相关系数 0.357，p=0.013）。这种影响在术后 6 个月和 12 个月时仍然存在（Spearman 相关系数 0.471，p=0.009 于术后 6 个月；0.472，p=0.008 于术后 12 个月）。Mann-Whitney U 检验显示，COR 内侧化组的表现明显差于 COR 外侧化组。这在出院时和术后 6 个月的巴氏指数以及术后 6 个月和 12 个月的 PMS 中都可以看到。准确重建的 COR 在护理和活动能力方面与外侧化的旋转中心没有显著差异。与 COR 下置组相比，COR 上置组在术后 12 个月的活动能力明显降低（p=0.008），与 COR 下置组相比，准确重建的旋转中心组在术后 6 个月（p=0.007）和 12 个月（p=0.026）时疼痛明显减轻。特别是两者的结合（中上置）会导致活动能力下降（Spearman 相关系数 0.67，p= < 0.001）。
COR 上移、COR 内侧化以及两者的结合（中上置，Spearman p= < 0.001）会导致活动能力下降，而 COR 下移会导致疼痛增加。根据我们的结果，我们建议准确恢复垂直 COR，同时避免水平内侧移位。
III 级。
