Low rate of return to pre-injury sport level in athletes after cartilage surgery: a 10-year follow-up study

Although articular surface is frequently damaged in athletes, results in terms of return to sport and level of activity after cartilage surgery remain rather unpredictable and poorly documented. The aim of this study is to evaluate the clinical outcome in terms of rate and level of return to sport in a group of competitive athletes who underwent matrix-assisted autologous chondrocyte transplantation (MACT), as well as the impact on their athletic career.

Thirty-one male patients (mean age 22.6 ± 6.3 years) p racticing sport at competitive level, affected by focal chondral/osteochondral lesions of the distal femur, were enrolled and treated with arthroscopic hyaluronan-based MACT. Patients were evaluated prospectively at 1-year intervals with the IKDC subjective, Tegner, and EuroQol VAS scores during their pre-operative visit and subsequent follow-ups for up to 10 years. Return to sport in terms of level, time and maintenance of the activity level was documented, together with surgical or clinical failures.

A marked improvement in all scores was found: IKDC increased from 40.3 ± 13.4 to 81.7 ± 14.4 (p < 0.0005) at 12 months; a further improvement was observed at 2 years (89.5 ± 11.3; p = 0.008), then results were stable for up to 10 years (87.3 ± 13.6). The analysis of return to sport documented that 64.5% of patients were able to return at a competitive level, and 58.1% performed at the same pre-injury level, with activity rates decreasing over time. The rate of patients returning to competitive level was 84% in those without previous surgery (vs. 33% who had undergone previous surgery), 87% for those with traumatic lesions (vs. 33% and 50% for degenerative and OCD lesions, respectively), and 92.3% in younger patients (age < 20 years). Among these factors, multivariate analysis demonstrated that previous surgery was the single most influencing factor for returning to the same sport level (p = 0.010).

These long-term results showed that chondrocyte-based regenerative approach has some limitations in terms of sport-related outcomes. The level of high functional knee restoration needed for such high-demanding activity level can be challenging to achieve, especially in patients with a more compromised joint homeostasis. Return to sport rate varies significantly according to specific patient and lesion characteristics and best results are obtained in young patients with traumatic lesions without previous surgery, which should be considered when treating athletes affected by cartilage lesions.

IV.