Mid-term outcomes of arthroscopic osteochondral autograft transplantation for focal chondral defects of the knee

Objectives: Osteochondral autograft transplantation (OAT) for the management of cartilage defect involves direct transfer of hyaline cartilage to the defect site. The study aims to assess mid-term functional outcomes of arthroscopic treatment of focal chondral defects of the knee using the OAT technique. Materials and Methods: In this prospective follow-up study, patients who had previously undergone an OAT procedure for chondral defects of the knee at least 2 years prior were included. All the cartilage defects were treated arthroscopically with one or two plugs. Patients were followed up at 2 time points – in June 2016 and June, 2020. The International Knee Documentation Committee (IKDC) score and Tegner activity scale (TAS) were recorded preoperatively and at both follow-ups. Results: There were 20 patients with 21 focal cartilage defects, comprising 14 males and 6 females, with an average age of 30.9 ± 7 years and mean body mass index (BMI) of 27.2 ± 4 kg/m2. The first follow-up was after a mean 42.4 ± 12 months and the second after mean 90.4 ± 11.9 months post-surgery. The IKDC score improved significantly at both follow-ups compared to pre-operative scores (P < 0.001). At the first follow-up, the mean change in IKDC score was 25.3 ± 16.7 with 14 patients (70%) achieving minimal clinically important difference (MCID) but only 5 (25%) achieving substantial clinical benefit (SCB). At the second follow-up, 16 patients (80%) achieved MCID and 8 (40%) achieved SCB in IKDC score, with a mean change of 28.3 ± 12.6. The TAS showed statistically significant improvement at the first follow-up (P = 0.011), but not at the second follow-up (P = 0.052). Conclusion: OAT for focal cartilage defects of the knee is an excellent option as it provides clinically significant and incremental improvement in functional results in the mid-term. The results are not inferior even when a concomitant ligament or meniscus surgery is performed. Higher age or BMI does not have a negative impact on the outcomes.

Arthroscopic versus Open Osteochondral Autograft Transplantation (Mosaicplasty) for Cartilage Damage of the Knee: A Systematic Review

Osteochondral autograft transplantation (OAT) is a surgical option for repairing cartilage damage in knees, and can be performed using open or arthroscopic procedures. The aim of this review was to report clinical outcomes, postoperative complications, defect location, and defect size between open and arthroscopic OATs. Three electronic databases (EMBASE, PUBMED, and MEDLINE) were searched for relevant articles. In regard to eligibility criteria, knee articular damage cases solely treated with OAT were included and cases concomitant with ligament reconstruction, limb realignment, and meniscus repair were excluded. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and descriptive statistics are presented. A total of 24 studies were included with a total sample of 1,139 patients (532 in open OAT vs. 607 in arthroscopic OAT). Defect size in open OAT was three times larger than that of arthroscopic OAT (2.96 ± 0.76 vs. 0.97 ± 0.48 cm2). In terms of defect location, the medial femoral condyle (MFC) was the most common (75.4%), followed by the lateral femoral condyle (LFC; 12.1%), patella (6.7%), and trochlea (5.7%). All of these defect locations were treated with open OAT, whereas arthroscopic OAT treatments were restricted to the MFC and LFC. The clinical outcomes were overall favorable with the modified Hospital for Special Surgery knee scores being 89.6 ± 8.0 (36.1-month follow-up) versus 90.4 ± 6.0 (89.5-month follow-up) and the Lysholm scores being 81.6 ± 8.9 (44.2-month follow-up) and 83.3 ± 7.4 (12.0-month follow-up) between open and arthroscopic OATs, respectively. Fifty-three postoperative complications were observed (39/279 vs. 14/594) and the most common complication was hemarthrosis (13/39 in open, vs. 1/14 in arthroscopic OAT). The overall clinical outcomes were favorable in open and arthroscopic OATs, whereas open OAT allowed for treatment of lesions approximately three times greater in dimension than in arthroscopic OAT. Also, defect location was restricted to MFC and LFC in arthroscopic OAT. The most common complication was hemarthrosis.