Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany, Berlin, Germany.
J Orthop Surg Res. 2022 Feb 2;17(1):64. doi: 10.1186/s13018-022-02945-5.
Spinopelvic mobility gained increased attention as a contributing factor for total hip arthroplasty (THA) instability. However, it is unknown how a pre-existing THA affects spinopelvic mobility. Therefore, a propensity-score-matched analysis of primary THA patients comparing the individual segments of spinopelvic mobility between patients with pre-existing THA and no-existing THA was conducted. Consequently, the study aimed to discuss (1) whether patients with a pre-existing THA have altered spinopelvic mobility compared to the control group and (2) if spinopelvic mobility changes after THA.
A prospective observational study enrolled 197 elective primary THA patients, including N = 44 patients with a pre-existing unilateral THA. Using propensity-score matching adapted for age, sex, and BMI, N = 44 patients without a pre-existing THA were determined. The patients received stereoradiography in standing and relaxed sitting position pre- and postoperatively. Assessed parameters were lumbar lordosis (LL), pelvic tilt (PT), and pelvic femoral angle (PFA). Key parameters of the spinopelvic mobility were defined as lumbar flexibility (∆LL = LL - LL), pelvic mobility (∆PT = PT - PT) and hip motion (∆PFA = PFA - PFA). Pelvic mobility was classified as stiff (∆PT < 10°), normal (∆PT ≥ 10°-30°) and hypermobile (∆PT > 30°). The Wilcoxon rank sum test for dependent samples was used.
Pelvic mobility was significantly increased in the pre-existing THA group (∆PT 18.2° ± 10.7) compared to the control group (∆PT 7.7° ± 8.0; p < 0.001) preoperatively and postoperatively (pre-existing: 22.2° ± 9.3; control: 17.0° ± 9.2, p = 0.022). Lumbar flexibility was significantly increased in the pre-existing THA group (∆LL 21.6° ± 11.8) compared to the control group (∆LL 12.4° ± 7.8; p < 0.001) preoperatively and postoperatively (pre-existing: 25.7° ± 11.0; control: 19.0° ± 10.2; p = 0.011). The contribution of stiff pelvic mobility is distinctly smaller in the pre-existing THA group (25%) than in the control group (75%) preoperatively.
Pre-existing THA is associated with significantly enhanced pelvic mobility and lumbar flexibility. Accordingly, we identified the patients without a pre-existing THA as risk candidates with higher likelihood for pathological spinopelvic mobility. This information will assist arthroplasty surgeons in deciding which THA candidates require preoperative radiological screening for pathologic spinopelvic mobility.
Level II prospective cohort study.
脊柱骨盆活动度作为全髋关节置换术（THA）不稳定的一个影响因素而受到越来越多的关注。然而，目前尚不清楚先前存在的 THA 如何影响脊柱骨盆活动度。因此，本研究采用倾向评分匹配分析，比较了有和无先前存在的 THA 的原发性 THA 患者的脊柱骨盆活动度各个节段，以评估以下内容：（1）先前存在 THA 的患者与对照组相比，脊柱骨盆活动度是否发生改变；（2）THA 后脊柱骨盆活动度是否发生变化。
前瞻性观察性研究纳入了 197 例接受初次择期 THA 的患者，包括 44 例先前存在单侧 THA 的患者。采用适用于年龄、性别和 BMI 的倾向评分匹配方法，确定了 44 例无先前 THA 的患者作为对照组。患者在术前和术后均接受站立位和放松坐姿的立体放射摄影检查。评估的参数包括腰椎前凸（LL）、骨盆倾斜（PT）和骨盆股骨角（PFA）。脊柱骨盆活动度的关键参数定义为腰椎灵活性（∆LL=LL-LL）、骨盆灵活性（∆PT=PT-PT）和髋关节运动（∆PFA=PFA-PFA）。骨盆灵活性分为僵硬（∆PT＜10°）、正常（∆PT≥10°-30°）和过度活跃（∆PT＞30°）。采用配对样本 Wilcoxon 秩和检验。
术前和术后，先前存在 THA 的患者的骨盆灵活性明显增加（∆PT 18.2°±10.7），与对照组（∆PT 7.7°±8.0；p＜0.001）相比。与对照组相比，先前存在 THA 的患者的腰椎灵活性明显增加（∆LL 21.6°±11.8），与对照组（∆LL 12.4°±7.8；p＜0.001）相比。术前和术后，先前存在 THA 的患者的腰椎灵活性均明显增加（∆LL 25.7°±11.0），与对照组（∆LL 19.0°±10.2；p=0.011）相比。术前，先前存在 THA 的患者中僵硬性骨盆活动度的比例（25%）明显低于对照组（75%）。
先前存在的 THA 与骨盆灵活性和腰椎灵活性明显增加有关。因此，我们将没有先前 THA 的患者确定为病理性脊柱骨盆活动度的高风险候选者。这些信息将有助于关节置换外科医生决定哪些 THA 患者需要术前进行影像学筛查以评估病理性脊柱骨盆活动度。
II 级前瞻性队列研究。
