Department of Orthopaedic Surgery, Perelman School of Medicine, Ringgold Standard Institution, University of Pennsylvania, Philadelphia, Pennsylvania.
Department of Orthopaedic Surgery, Hospital for Special Surgery, New York City, New York.
J Knee Surg. 2023 Oct;36(12):1283-1288. doi: 10.1055/s-0042-1755354. Epub 2022 Sep 1.
Osteoarthritis (OA) in the knee is common, painful, and may be uni- or multicompartmental. The compartment affected by arthritis may be due to trauma, malalignment (varus or valgus), or in the case of patellofemoral OA, patella alta. Patellofemoral arthroplasty (PFA) is an effective partial knee replacement surgery for patellofemoral OA. We hypothesized that PFA can decrease patellar height. In addition, we predicted better outcomes for patients with patella alta before PFA and those whose patellar heights decreased after PFA. This is a retrospective cohort study of PFA patients from 2012 to 2020. Before and after PFA, we measured patellar heights on X-ray images and collected patient-reported outcome measures (PROMs) (International Knee Documentation Committee score, Kujala Anterior Knee Pain Score, and Veterans RAND 12-Item Health Survey for mental and physical health). Statistical analyses assessed PROMs and compared outcomes based on pre- and postoperative patella height. Of 133 knees, 73% presented with patella alta and 61% had patellar heights that decreased after PFA. Compared with patients who did not present with patella alta, patients with patella alta reported similar outcomes with respect to knee function, pain, and general physical and mental health. Compared with patients whose patellar heights decreased after PFA, patients whose knees did not decrease in height reported greater improvements in pain and function. Our findings suggest that patella alta is commonly found in patients with patellofemoral OA and that PFA can decrease patellar height. Future studies are needed to assess whether patellofemoral OA patients with greater degrees of patella alta would benefit from staged or concurrent tibial tubercle distalization.
膝关节骨关节炎（OA）很常见，且疼痛明显，可能是单部位或多部位的。受关节炎影响的部位可能是由于创伤、对线不良（内翻或外翻），或者在髌股关节炎的情况下，髌骨高位。髌股关节置换术（PFA）是治疗髌股关节炎的一种有效的膝关节部分置换手术。我们假设 PFA 可以降低髌骨高度。此外，我们预测在 PFA 前髌骨高位的患者和 PFA 后髌骨高度降低的患者会有更好的结果。这是一项对 2012 年至 2020 年接受 PFA 的患者的回顾性队列研究。在 PFA 前后，我们在 X 光片上测量髌骨高度，并收集患者报告的结果测量（国际膝关节文献委员会评分、Kujala 髌前膝关节疼痛评分和退伍军人 RAND 12 项健康调查用于心理健康和身体健康）。统计分析评估了 PROMs，并根据术前和术后髌骨高度比较了结果。在 133 个膝关节中，73%存在髌骨高位，61%的膝关节在 PFA 后髌骨高度降低。与没有髌骨高位的患者相比，髌骨高位的患者在膝关节功能、疼痛和一般身体和心理健康方面报告的结果相似。与 PFA 后髌骨高度降低的患者相比，膝关节高度没有降低的患者在疼痛和功能方面的改善更大。我们的研究结果表明，髌股关节炎患者中髌骨高位很常见，PFA 可以降低髌骨高度。需要进一步研究来评估髌股关节炎患者髌骨高位程度更大是否会受益于分期或同期胫骨结节下移。
