Jung Woon-Hwa, Takeuchi Ryohei, Chun Chung-Woo, Lee Jung-Su, Jeong Jae-Heon
Department of Orthopaedic Surgery, Murup Hospital, Gyeongnam, Republic of Korea.
Yokosuka Municipal Hospital, Kanagawa, Japan.
Arthroscopy. 2015 Apr;31(4):673-9. doi: 10.1016/j.arthro.2014.11.035. Epub 2015 Jan 27.
The purposes of this study were to compare the results of medial opening-wedge high tibial osteotomy (MOWHTO) with and without subchondral drilling and to assess the formation of fibrocartilage at 2 years postoperatively.
Patients were divided into 2 groups. Thirty knees were treated with osteotomy and subchondral drilling (group 1), and 31 knees were treated with osteotomy alone (group 2). Clinical evaluations were performed by use of Knee Society scores preoperatively and at 2 years postoperatively. For evaluation of cartilage degeneration, the International Cartilage Repair Society grading system was used for arthroscopic grading on initial arthroscopy during high tibial osteotomy. The patients underwent a second-look arthroscopic evaluation of the articular cartilage at the time of removal of the plate, an average of 2 years after the initial osteotomy. For evaluation of formation of fibrocartilage on second-look arthroscopy, the articular cartilage was classified as having either no change from initial surgery (grade I) or white scattering with fibrocartilage, partial coverage with fibrocartilage, or even coverage with fibrocartilage (grade II). In addition, maturation of the appearance of the cartilage was defined. The appearance was considered mature if the chondral defects were evenly covered with fibrocartilage. It was considered immature if there was white scattering or only partial coverage with fibrocartilage.
In group 1 the mean Knee Society knee score and function score were 67.3 ± 8.2 points and 66.5 ± 14.3 points, respectively, preoperatively. At 2 years postoperatively, they improved to 91.2 ± 6.4 and 92.8 ± 10.0, respectively (P = .001 and P = .001, respectively). In group 2 the mean Knee Society knee score and function score were 63.7 ± 13.9 points and 66.8 ± 9.1 points, respectively, preoperatively. At 2 years postoperatively, they improved to 92.5 ± 5.3 points and 92.2 ± 8.0 points, respectively (P = .001 and P = .001, respectively). There were no significant differences in the postoperative Knee Society knee score and function score at 2 years' follow-up between the groups (P = .389 and P = .806, respectively). Grade II regeneration was achieved in the medial femoral condyle articular cartilage in 100% of knees in group 1 and 94% of knees in group 2 (P = .492). Maturation of the cartilage was found in the medial femoral condyle articular cartilage in 10% of knees in group 1 and 3% of knees in group 2 (P = .354). There was no significant difference in the formation of fibrocartilage between the groups.
Subchondral drilling had no effect on the outcome at 2 years after MOWHTO. In addition, there was no significant difference in the formation of fibrocartilage with or without subchondral drilling. Therefore subchondral drilling is not necessary after MOWHTO.
Level III, retrospective comparative study.
本研究旨在比较行与不行软骨下钻孔的内侧开放楔形高位胫骨截骨术（MOWHTO）的结果，并评估术后2年时纤维软骨的形成情况。
患者被分为2组。30例膝关节接受了截骨术及软骨下钻孔（第1组），31例膝关节仅接受了截骨术（第2组）。术前及术后2年采用膝关节协会评分进行临床评估。为评估软骨退变情况，在高位胫骨截骨术时，初次关节镜检查采用国际软骨修复协会分级系统进行分级。患者在初次截骨术后平均2年取出钢板时接受二次关节镜检查以评估关节软骨情况。为评估二次关节镜检查时纤维软骨的形成情况，将关节软骨分类为与初次手术相比无变化（I级）或有白色散在纤维软骨、部分纤维软骨覆盖或完全纤维软骨覆盖（II级）。此外，还定义了软骨外观的成熟度。如果软骨缺损被纤维软骨均匀覆盖，则认为外观成熟；如果有白色散在或仅有部分纤维软骨覆盖，则认为不成熟。
第1组术前膝关节协会膝关节评分和功能评分的平均值分别为67.3±8.2分和66.5±14.3分。术后2年时，分别提高到91.2±6.4分和92.8±10.0分（P分别为0.001和0.001）。第2组术前膝关节协会膝关节评分和功能评分的平均值分别为63.7±13.9分和66.8±9.1分。术后2年时，分别提高到92.5±5.3分和92.2±8.0分（P分别为0.001和0.001）。两组在术后2年随访时膝关节协会膝关节评分和功能评分无显著差异（P分别为0.389和0.806）。第1组中内侧股骨髁关节软骨100%实现II级再生，第2组中为94%（P=0.492）。第1组中内侧股骨髁关节软骨10%出现软骨成熟，第2组中为3%（P=0.354）。两组之间纤维软骨的形成无显著差异。
软骨下钻孔对MOWHTO术后2年的结果无影响。此外，行与不行软骨下钻孔在纤维软骨形成方面无显著差异。因此，MOWHTO术后无需进行软骨下钻孔。
III级，回顾性比较研究。
