Favorable 10-year outcomes of osteochondral autologous transplantation for spontaneous osteonecrosis of the knee following subchondral insufficiency fracture with optimal alignment correction.
{"title":"Favorable 10-year outcomes of osteochondral autologous transplantation for spontaneous osteonecrosis of the knee following subchondral insufficiency fracture with optimal alignment correction.","authors":"Kohei Nishitani, Yasuaki Nakagawa, Masahiko Kobayashi, Shinichiro Nakamura, Shogo Mukai, Shinichi Kuriyama, Shuichi Matsuda","doi":"10.1186/s43019-025-00285-2","DOIUrl":null,"url":null,"abstract":"<p><strong>Purpose: </strong>The long-term effect of osteochondral autologous transplantation (OAT) on spontaneous osteonecrosis of the knee (SONK) following subchondral insufficiency fracture remains unclear. This study aimed to evaluate the long-term survivorship and clinical outcomes of OAT for SONK, with a focus on factors associated with clinical success.</p><p><strong>Methods: </strong>Patients who underwent OAT for SONK between 1998 and 2009 were retrospectively reviewed. Survivorship was assessed using Kaplan-Meier analysis, with revision surgery as the endpoint. Clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC) subjective score obtained preoperatively and at final follow-up. Clinical failure was defined as an IKDC score below the patient acceptable symptom state (PASS; 62.1 points). The association between final IKDC score and postoperative femorotibial angle (FTA) was analyzed using linear and quadratic regression.</p><p><strong>Results: </strong>A total of 33 OATs were included (mean age: 64.6 ± 8.0 years; mean lesion size: 3.9 ± 1.7 cm<sup>2</sup>). High tibial osteotomy was performed in 15 patients with FTA > 180°, and 24 patients were followed for ≥ 10 years (mean: 13.7 ± 3.4 years). One arthroplasty was performed at 14.2 years, yielding a 15-year survival rate of 88%. The IKDC score improved significantly (35.0 ± 12.6 to 70.6 ± 14.1, p < 0.001), with a clinical success rate of 79.2%. Quadratic regression showed optimal postoperative FTA between 163.1° and 178.3° for achieving PASS.</p><p><strong>Conclusions: </strong>OAT may provide favorable long-term survivorship and clinical outcomes in SONK, particularly when postoperative alignment is appropriately corrected.</p>","PeriodicalId":36317,"journal":{"name":"Knee Surgery and Related Research","volume":"37 1","pages":"34"},"PeriodicalIF":4.4000,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12341072/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Knee Surgery and Related Research","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1186/s43019-025-00285-2","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"Medicine","Score":null,"Total":0}
引用次数: 0
Abstract
Purpose: The long-term effect of osteochondral autologous transplantation (OAT) on spontaneous osteonecrosis of the knee (SONK) following subchondral insufficiency fracture remains unclear. This study aimed to evaluate the long-term survivorship and clinical outcomes of OAT for SONK, with a focus on factors associated with clinical success.
Methods: Patients who underwent OAT for SONK between 1998 and 2009 were retrospectively reviewed. Survivorship was assessed using Kaplan-Meier analysis, with revision surgery as the endpoint. Clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC) subjective score obtained preoperatively and at final follow-up. Clinical failure was defined as an IKDC score below the patient acceptable symptom state (PASS; 62.1 points). The association between final IKDC score and postoperative femorotibial angle (FTA) was analyzed using linear and quadratic regression.
Results: A total of 33 OATs were included (mean age: 64.6 ± 8.0 years; mean lesion size: 3.9 ± 1.7 cm2). High tibial osteotomy was performed in 15 patients with FTA > 180°, and 24 patients were followed for ≥ 10 years (mean: 13.7 ± 3.4 years). One arthroplasty was performed at 14.2 years, yielding a 15-year survival rate of 88%. The IKDC score improved significantly (35.0 ± 12.6 to 70.6 ± 14.1, p < 0.001), with a clinical success rate of 79.2%. Quadratic regression showed optimal postoperative FTA between 163.1° and 178.3° for achieving PASS.
Conclusions: OAT may provide favorable long-term survivorship and clinical outcomes in SONK, particularly when postoperative alignment is appropriately corrected.