Park Jun-Gu, Han Seung-Beom, Jang Ki-Mo, Shin Seung-Min
Department of Orthopaedic Surgery, Anam Hospital, Korea University College of Medicine, Seoul, South Korea.
Arch Orthop Trauma Surg. 2025 Jan 11;145(1):119. doi: 10.1007/s00402-024-05718-3.
There is a lack of clinical evidence supporting the decision-making process between high tibial osteotomy (HTO) and unicomparmental knee arthroplasty (UKA) in gray zone indication, such as moderate medial osteoarthritis with moderate varus alignment. This study compared the outcomes between HTO and UKA in such cases and assessed the risk factor for not maintaining clinical improvements.
We retrospectively reviewed 65 opening-wedge HTOs and 55 UKAs with moderate medial osteoarthritis (Kellgren-Lawrence grade ≥ 3 and Ahlback grade < 3) and moderate varus alignment (5°< Hip-Knee-Ankle angle < 10°) over 3 years follow-up. Confounding factors including patient demographics, postoperative lower limb alignment was assessed. Dummy variable was used to categorize the HTO and UKA according to presence of tibia varus deformity (medial proximal tibial angle of 85°). Clinical outcomes were measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score preoperatively, 1 year postoperatively, and at the last follow-up. Cox regression analysis identified risk factors for not achieving minimal clinically important differences (MCID) in WOMAC scores.
The WOMAC score at 1-postoperative year significantly improved beyond MCID in all UKA and HTO. However, over a mean follow-up of 68.7 months (HTO) and 64.3 months (UKA), 16 patients (13.3%) experienced clinical deterioration. Notably, patients with suboptimal postoperative alignment, those undergoing HTO without tibial vara, and UKA with tibial vara had higher risks of clinical deterioration during the mid-term period.
Tibial varus deformity differentially affects clinical outcomes after HTO and UKA in moderate medial compartment osteoarthritis with moderate varus alignment. Clinicians should consider the deformity's origin when selecting treatment for this patient, as certain combinations (HTO without tibia vara and UKA with tibia vara) are associated with increased risk of not maintaining mid-term clinical improvements.
在灰色地带适应症（如中度内侧骨关节炎伴中度内翻畸形）中，缺乏支持高位胫骨截骨术（HTO）与单髁膝关节置换术（UKA）决策过程的临床证据。本研究比较了此类病例中HTO和UKA的疗效，并评估了未维持临床改善的风险因素。
我们回顾性分析了65例开放性楔形HTO和55例UKA，这些患者患有中度内侧骨关节炎（Kellgren-Lawrence分级≥3级且Ahlback分级<3级）和中度内翻畸形（髋-膝-踝角5°<Hip-Knee-Ankle angle<10°），随访时间超过3年。评估了包括患者人口统计学、术后下肢对线等混杂因素。使用虚拟变量根据胫骨内翻畸形的存在（胫骨近端内侧角为85°）对HTO和UKA进行分类。术前、术后1年和末次随访时使用西安大略和麦克马斯特大学骨关节炎指数（WOMAC）评分测量临床结果。Cox回归分析确定了WOMAC评分未达到最小临床重要差异（MCID）的风险因素。
所有UKA和HTO术后1年的WOMAC评分均显著改善，超过了MCID。然而，在平均随访68.7个月（HTO）和64.3个月（UKA）期间，16例患者（13.3%）出现临床恶化。值得注意的是，术后对线欠佳的患者、未合并胫骨内翻而行HTO的患者以及合并胫骨内翻的UKA患者在中期临床恶化风险较高。
在中度内侧间室骨关节炎伴中度内翻畸形的情况下，胫骨内翻畸形对HTO和UKA术后的临床结果有不同影响。临床医生在为该类患者选择治疗方法时应考虑畸形的来源，因为某些组合（未合并胫骨内翻的HTO和合并胫骨内翻的UKA）与中期未维持临床改善的风险增加有关。
