Vorimore Camille, Strat Vincent Le, Marmor Simon, Graff Wilfrid, Mouton Antoine, Aubert Thomas
Orthopaedic Department, Croix St Simon Hospital, 125 rue d'Avron, 75020 Paris, France.
Orthopaedic Department, Croix St Simon Hospital, 125 rue d'Avron, 75020 Paris, France.
Orthop Traumatol Surg Res. 2025 Jun 11:104315. doi: 10.1016/j.otsr.2025.104315.
Hip dislocation remains one of the most frequent complications of total hip arthroplasty (THA). To minimize the risk of dislocation, cup placement has traditionally been guided by a defined "safe zone". However, dislocations still occur even when the implant components are positioned within this zone, which may be due to the influence of spinopelvic motion on THA stability. This study aimed to (1) compare spinopelvic risk factors for dislocation between patients who experienced dislocations and those who did not after anterior-approach surgery and (2) analyze the risk factors associated with anterior versus posterior dislocations.
Our hypothesis was that patients with dislocation of a total hip arthroplasty after the anterior approach had a higher rate of risk factors for adverse spinopelvic mobility and that implant versions, as well as hip lengths and offsets, play an important role in anterior and posterior dislocations.
Patient with dislocation were prospectively collected from August 2018 to August 2022. Out of a total of 6,166 THAs, 35 dislocations were recorded, and 7 patients were excluded. This single-center study included a prospective cohort of 28patients who experienced dislocations (19 anterior, 9 posterior) compared with a consecutive control cohort of 278 patients who did not, all of whom underwent primary THA via the anterior approach. Preoperative spinopelvic parameters such as lumbar flexion (LF), spinopelvic tilt (SPT), pelvic incidence (PI), and pelvic mobility (change in SPT [ΔSPT]) were analyzed in the control group using pelvic-femoral computed tomography and lateral X-rays. Patients who experienced dislocation underwent advanced postoperative functional analysis, in which spinopelvic parameters, implant version, hip length discrepancy, and femoral offset were assessed.
The prevalence of spinopelvic risk factors was greater in the dislocation cohort than in the control cohort [SPT≤-10°: 42.5% vs. 10.5% (p < 0.001); LF ≤ 35°: 46.1% vs. 11.9% (p < 0.001); PI-lumbar lordosis (LL) ≥ 10°: 33.9% vs. 14.8% (p = 0.003); ΔSPT ≥ 20 ° from standing to seated: 50% vs. 8.3% (p < 0.001); and ΔSPT ≤-13 ° from supine to standing: 21.4% vs. 6.7% (p = 0.012)]. The mean combined anteversion (CA) was 35 ° (7°-53 °) in the anterior dislocation group and 24 ° (15°-30 °) in the posterior dislocation group.
Patients with dislocations presented a high prevalence of spinopelvic risk factors. Anterior dislocations were linked to spinopelvic abnormalities rather than excessive CA. In contrast, posterior dislocations occurred in patients with low CA, especially at the expense of stem version and spinopelvic risk factors. Therefore, in patients undergoing anterior-approach THA, restricting implant anteversion may not be the primary factor in reducing the risk of anterior dislocation but may increase the risk of posterior dislocation in patients with adverse spinopelvic mobility.
III; Case-control study.
髋关节脱位仍然是全髋关节置换术（THA）最常见的并发症之一。为了将脱位风险降至最低，传统上髋臼杯的放置是由一个明确的“安全区”来指导的。然而，即使植入部件位于该区域内，脱位仍会发生，这可能是由于脊柱骨盆运动对THA稳定性的影响。本研究旨在（1）比较前路手术后发生脱位的患者与未发生脱位的患者之间脊柱骨盆脱位的危险因素，以及（2）分析与前脱位和后脱位相关的危险因素。
我们的假设是，前路全髋关节置换术后脱位的患者出现不良脊柱骨盆活动度危险因素的发生率更高，并且植入物的版本以及髋关节长度和偏心距在前脱位和后脱位中起重要作用。
前瞻性收集2018年8月至2022年8月发生脱位的患者。在总共6166例THA中，记录了35例脱位，排除7例患者。这项单中心研究包括一个前瞻性队列，其中28例患者发生脱位（19例前脱位，9例后脱位），并与一个连续的278例未发生脱位的对照组进行比较，所有患者均通过前路进行初次THA。在对照组中，使用骨盆-股骨计算机断层扫描和侧位X线分析术前脊柱骨盆参数，如腰椎前屈（LF）、脊柱骨盆倾斜（SPT）、骨盆入射角（PI）和骨盆活动度（SPT变化[ΔSPT]）。发生脱位的患者接受了术后高级功能分析，评估了脊柱骨盆参数、植入物版本、髋关节长度差异和股骨偏心距。
脱位队列中脊柱骨盆危险因素的患病率高于对照组[SPT≤-10°：42.5%对10.5%（p<0.001）；LF≤35°：46.1%对11.9%（p<0.001）；PI-腰椎前凸（LL）≥10°：33.9%对14.8%（p=0.003）；站立到坐姿时ΔSPT≥20°：50%对8.3%（p<0.001）；仰卧到站立时ΔSPT≤-13°：21.4%对6.7%（p=0.012）]。前脱位组的平均联合前倾角（CA）为35°（7°-53°），后脱位组为24°（15°-30°）。
脱位患者中脊柱骨盆危险因素的患病率较高。前脱位与脊柱骨盆异常有关，而不是与过度的CA有关。相比之下，后脱位发生在CA较低的患者中，尤其是以柄部版本和脊柱骨盆危险因素为代价。因此，在接受前路THA的患者中，限制植入物前倾角可能不是降低前脱位风险的主要因素，但可能会增加脊柱骨盆活动度不良患者的后脱位风险。
III；病例对照研究。
