Department of Orthopedic Surgery, Medical Center, Asklepios Klinikum Bad Abbach, Regensburg University, Kaiser-Karl V.-Allee 3, 93077, Bad Abbach, Germany.
Arch Orthop Trauma Surg. 2022 Apr;142(4):673-680. doi: 10.1007/s00402-021-03913-0. Epub 2021 May 21.
Femoral component subsidence is a known risk factor for early failure of total hip arthroplasty (THA) using cementless stems. The aim of the study was to compare an enhanced recovery concept with early full weight-bearing rehabilitation and partial weight-bearing on stem subsidence. In addition, the influence of patient-related and anatomical risk factors on subsidence shall be assessed.
One hundred and fourteen patients underwent primary cementless THA and were retrospectively analyzed. Sixty-three patients had an enhanced recovery rehabilitation with early full weight-bearing and 51 patients had rehabilitation with partial weight-bearing (20 kg) for 6 weeks. Postoperative subsidence was analyzed on standing pelvic anterior-posterior radiographs after 4 weeks and 1 year. Subsidence was measured in mm. Anatomical and prosthetic risk factors (stem size, canal flare index, canal fill ratio as well as BMI and demographic data) were correlated.
Femoral stem subsidence rate was significantly higher for the group with an enhanced recovery concept compared to the group with partial weight-bearing at the first radiological follow up after 4 weeks [2.54 mm (SD ± 1.86) vs. 1.55 mm (SD ± 1.80)] and the second radiological follow up after 1 year [3.43 mm (SD ± 2.24) vs. 1.94 (SD ± 2.16)] (p < 0.001, respectively). Stem angulation > 3° had a significant influence on subsidence. Canal flare index and canal fill ratio showed no significant correlation with subsidence as well as BMI and age.
In the present study, cementless stem subsidence was significantly higher in the group with enhanced recovery rehabilitation compared to partial weight-bearing. Small absolute values and differences were demonstrated and therefore possibly below clinical relevance. Anatomical radiological parameters and anthropometric data did not appear to be risk factors for stem subsidence.
股骨部件沉降是使用非骨水泥柄的全髋关节置换术（THA）早期失败的已知风险因素。本研究的目的是比较增强恢复概念与早期完全负重康复和部分负重对柄沉降的影响。此外，还评估了与患者相关和解剖风险因素对沉降的影响。
对 114 例行初次非骨水泥 THA 的患者进行回顾性分析。63 例患者采用增强康复康复，早期完全负重，51 例患者采用部分负重（20kg）6 周。术后 4 周和 1 年时在站立骨盆前后位 X 线片上分析沉降。沉降以毫米为单位进行测量。分析解剖和假体风险因素（柄大小、管扩张指数、管填充率以及 BMI 和人口统计学数据）。
与部分负重组相比，在增强康复组的第一次术后 4 周和第二次术后 1 年的放射学随访中，股骨柄沉降率明显更高[分别为 2.54mm（SD±1.86）比 1.55mm（SD±1.80）和 3.43mm（SD±2.24）比 1.94mm（SD±2.16）]（p<0.001）。柄角度>3°对沉降有显著影响。管扩张指数和管填充率与沉降以及 BMI 和年龄均无显著相关性。
在本研究中，与部分负重相比，增强康复康复组的非骨水泥柄沉降明显更高。虽然绝对值和差异较小，但可能低于临床相关。解剖影像学参数和人体测量学数据似乎不是柄沉降的危险因素。
