Tay Mei Lin, Bolam Scott M, Campbell Tyler, Hill Laura, Lin Lydia, Wong Hayley, Dow David, Munro Jacob T, Young Simon W, Monk A Paul
Department of Surgery, Faculty of Medical and Health Sciences (FMHS), University of Auckland, Auckland, New Zealand.
Department of Orthopaedic Surgery, North Shore Hospital, Auckland, New Zealand.
Knee Surg Sports Traumatol Arthrosc. 2025 Jun;33(6):2214-2221. doi: 10.1002/ksa.12611. Epub 2025 Feb 10.
For unicompartmental knee arthroplasty (UKA), patient selection using correct indications can optimise postsurgical outcomes. The current gold standard for assessing eligibility is with radiographs; however, magnetic resonance imaging (MRI) may allow for more accurate assessments of cartilage damage. This study aimed to evaluate the utility of MRI for preoperative assessment of medial UKA patients by (1) comparing osteoarthritis severity of the medial, lateral and patellofemoral (PF) compartments when assessed using MRI compared with standard radiographs, and (2) investigating associations of these two assessments with postoperative clinical outcomes.
This study had ethical approval. A retrospective review was performed for 88 primary medial UKA between 1 January 2017 and 31 December 2021. The main outcome measures were preoperative cartilage loss and patient-reported clinical outcomes. Preoperative cartilage loss was recorded using the International Cartilage Repair Society (ICRS) classification using MRI, and Kellgren-Lawrence (K-L) scores from radiographs. Patient-reported clinical outcomes were measured using preop, early (6-week) and late (1- or 2-year) Oxford Knee Score (OKS) change scores.
The use of MRI has improved accuracy over radiographs. In the medial compartment, 37 (44%) patients had less severe radiographic K-L scores (1-3); however, all patients had the most severe MRI ICRS scores (4). For patients with mild K-L scores (0 and 1), 20 (43%) and 7 (78%) patients had more severe ICRS scores (3 and 4) within their lateral and PF compartments, respectively. No associations were found between ICRS or K-L scores and OKS for any compartments.
Assessment of medial cartilage thickness loss using MRI provides additional utility over standard radiographs in preoperative assessments of medial UKA patients. However, evidence of disease in the PF compartment assessed using MRI should not be considered a contraindication for UKA.
Level III, retrospective cohort study.
对于单髁膝关节置换术（UKA），使用正确的适应症进行患者选择可优化术后结果。目前评估 eligibility 的金标准是通过 X 光片；然而，磁共振成像（MRI）可能会更准确地评估软骨损伤。本研究旨在通过（1）比较使用 MRI 与标准 X 光片评估时内侧、外侧和髌股（PF）关节腔的骨关节炎严重程度，以及（2）研究这两种评估与术后临床结果的相关性，来评估 MRI 对内侧 UKA 患者术前评估的效用。
本研究获得伦理批准。对 2017 年 1 月 1 日至 2021 年 12 月 31 日期间的 88 例初次内侧 UKA 进行回顾性研究。主要结局指标为术前软骨损失和患者报告的临床结果。术前软骨损失通过使用 MRI 的国际软骨修复协会（ICRS）分类记录，以及通过 X 光片的 Kellgren-Lawrence（K-L）评分记录。患者报告的临床结果使用术前、早期（6 周）和晚期（1 年或 2 年）牛津膝关节评分（OKS）变化评分进行测量。
与 X 光片相比，MRI 的使用提高了准确性。在内侧关节腔，37 例（44%）患者的 X 光片 K-L 评分（1-3 级）较轻；然而，所有患者的 MRI ICRS 评分均为最严重的（4 级）。对于 K-L 评分较轻（0 级和 1 级）的患者，分别有 20 例（43%）和 7 例（78%）患者在其外侧和 PF 关节腔内的 ICRS 评分更严重（3 级和 4 级）。在任何关节腔中，均未发现 ICRS 或 K-L 评分与 OKS 之间存在关联。
在对内侧 UKA 患者进行术前评估时，使用 MRI 评估内侧软骨厚度损失比标准 X 光片具有更多效用。然而，使用 MRI 评估的 PF 关节腔疾病证据不应被视为 UKA 的禁忌症。
III 级，回顾性队列研究。
