Department for Orthopedic Sports Medicine, Technical University Munich, Ismaninger Str. 22, 81675, Munich, Germany.
Department of Orthopaedics and Trauma Surgery, Medical Center, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany.
Arch Orthop Trauma Surg. 2020 Dec;140(12):2029-2039. doi: 10.1007/s00402-020-03651-9. Epub 2020 Oct 30.
To analyze whether preoperative patellofemoral anatomy is associated with clinical improvement and failure rate after isolated patellofemoral arthroplasty (PFA) using a modern inlay-type trochlear implant.
Prospectively collected 24 months data of patients treated with isolated inlay PFA (HemiCAP Wave, Arthrosurface, Franklin, MA, USA) between 2009 and 2016, and available digitalized preoperative imaging (plain radiographs in three planes and MRI) were retrospectively analyzed. All patients were evaluated using the WOMAC score, Lysholm score, and VAS pain. Patients revised to TKA or not achieving the minimal clinically important difference (MCID) for the total WOMAC score or VAS pain were considered failures. Preoperative imaging was analyzed regarding the following aspects: Tibiofemoral OA, patellofemoral OA, trochlear dysplasia (Dejour classification), patellar height (Insall-Salvati index [ISI]; Patellotrochlear index [PTI]), and position of the tibial tuberosity (TT-TG and TT-PCL distance).
A total of 41 patients (61% female) with a mean age of 48 ± 13 years could be included. Fifteen patients (37%) were considered failures, with 5 patients (12%) revised to TKA and 10 patients (24%) not achieving MCID for WOMAC total or VAS pain. Failures had a significantly higher ISI, and a significantly lower PTI. Furthermore, the proportion of patients with a pathologic ISI (> 1.2), a pathologic PTI (< 0.28), and without trochlear dysplasia were significantly higher in failures. Significantly greater improvements in clinical outcome scores were observed in patients with a higher preoperative grade of patellofemoral OA, ISI ≤ 1.2, PTI ≥ 0.28, TT-PCL distance ≤ 21 mm, and a dysplastic trochlea.
Preoperative patellofemoral anatomy is significantly associated with clinical improvement and failure rate after isolated inlay PFA. Less improvement and a higher failure rate must be expected in patients with patella alta (ISI > 1.2 and PTI < 0.28), absence of trochlear dysplasia, and a lateralized position of the tibial tuberosity (TT-PCL distance > 21 mm). Concomitant procedures such as tibial tuberosity transfer may, therefore, be considered in such patients.
Level III, retrospective analysis of prospectively collected data.
分析在使用现代嵌入式滑车假体进行单纯髌股关节炎（PFA）手术后，术前髌股解剖结构与临床改善和失败率之间的关系。
前瞻性收集 2009 年至 2016 年间使用嵌入式滑车假体（HemiCAP Wave、Arthrosurface、Franklin，MA，美国）治疗的单纯髌股关节炎患者 24 个月的数据，并对现有的数字化术前影像学（三个平面的普通放射照片和 MRI）进行回顾性分析。所有患者均采用 WOMAC 评分、Lysholm 评分和 VAS 疼痛评分进行评估。将翻修至 TKA 或未达到 WOMAC 总分或 VAS 疼痛最小临床重要差异（MCID）的患者视为失败。对术前影像学进行以下方面的分析：胫股关节炎、髌股关节炎、滑车发育不良（Dejour 分类）、髌骨高度（Insall-Salvati 指数 [ISI]；髌骨-滑车指数 [PTI]）和胫骨结节位置（TT-TG 和 TT-PCL 距离）。
共纳入 41 例（61%为女性），平均年龄 48±13 岁。15 例（37%）患者被认为失败，其中 5 例（12%）翻修至 TKA，10 例（24%）未达到 WOMAC 总分或 VAS 疼痛的 MCID。失败组的 ISI 明显较高，PTI 明显较低。此外，失败组中病理性 ISI（>1.2）、病理性 PTI（<0.28）和无滑车发育不良的患者比例明显更高。术前髌股关节炎分级较高、ISI≤1.2、PTI≥0.28、TT-PCL 距离≤21mm 和滑车发育不良的患者，临床结局评分的改善更为显著。
术前髌股解剖结构与单纯嵌入式髌股关节炎置换术后的临床改善和失败率显著相关。对于髌骨高位（ISI>1.2 和 PTI<0.28）、滑车发育不良、胫骨结节外侧化（TT-PCL 距离>21mm）的患者，预计改善效果较差，失败率较高。因此，对于此类患者可考虑进行胫骨结节转移等伴随手术。
三级，前瞻性收集数据的回顾性分析。
