Single-plug osteochondral autograft transplantation for knee osteochondritis dissecans: Clinical improvement and long-term survivorship at a minimum ten year follow-up.

Purpose: Osteochondritis dissecans (OCD) can lead to detrimental effects in the affected joints. Osteochondral autologous transplantation (OAT) allows to restore the articular surface with an autologous osteochondral unit. While short-term results are documented, there is a lack of long-term data. Aim of this study was to analyze the long-term clinical results of single-plug OAT for the treatment of knee OCD.

Methods: Twenty patients (14 men, 6 women) were treated with single plug-OAT. Mean age was 23.6 ± 9.9 years and BMI was 23.3 ± 3.6 kg/m². Lesion size was 2.3 ± 1.6 cm² and defects included 14 medial femoral condyles (MFC) and 6 lateral femoral condyles (LFC). Patients were followed up prospectively at baseline, 24 months, 60 months, and at minimum ten years (12.6 ± 2.0 years) using the IKDC subjective score and through an overall judgment on treatment satisfaction. The activity level was evaluated with the Tegner score and adverse events and failures were also recorded. Factors influencing the clinical outcomes, including age, sex, BMI, lesions size, and lesion location were also investigated.

Results: No severe adverse events and no surgical failures were reported and 85.0% of patients were satisfied at a minimum ten year follow-up. Subjective IKDC showed a significant and stable improvement at all follow-ups, passing from 45.3 ± 16.5 at baseline to 73.7 ± 16.6 at 24 months (p < 0.0005), to 72.9 ± 16.6 at 60 months (p < 0.0005), and to 74.1 ± 20.8 at long-term follow-up (p < 0.0005). Patients with OCD lesions localized on the LFC obtained lower results compared to those with MFC lesions at two years and five years (p = 0.034 and p = 0.023). The highest long-term scores were obtained in patients with lesion size lower than 2 cm² (89.1 ± 8.8) compared to patients with lesion size between 2 and 4 cm² (69.2 ± 15.7), and patients with lesion size larger than 4 cm² (63.8 ± 34.6).

Conclusions: OAT is a suitable technique to treat knee OCD in young patients and offers a high patient satisfaction and a significant improvement in terms of clinical subjective scores, with results remaining stable over time, although without reaching the pre-injury activity level. No severe adverse events and no surgical failures have been documented confirming OAT as a valid treatment option, although the best long-term results for lesions smaller than 2 cm² and for MFC lesions should be considered when choosing this procedure to address knee OCD lesions.