Background & Aim: Recent studies have claimed good results after ACI in athletes. Our aim was to evaluate the early functional outcome and activity level after 2-stage ACI in professional athletes and soldiers.

Methods: Thirteen soldiers and five professional athletes (14 men and 4 women; average age 31 years), with 21 full thickness cartilage defects (ICRS grade-IV) of the knee were treated with 2-stage ACI. Mean interval between injury and surgery was 43.8 months. Average defect size was 6.03 cm² and was located to the MFC in 7 cases, LFC in 7 cases and the femoral trochlea in one case. The functional outcome was evaluated with ICRS form, Tegner activity rating scale and Lysholm score after a mean follow up period of 23.4 (18–32) months.

Results: The ICRS and Lysholm scores were improved from 42.7 and 47.6 pre-operatively to 63.1 and 69.9 respectively. The average Tegner scale was 8.8 pre-injury, 3.7 prior to surgery and 6.4 at the final follow up. Nine patients (50%) underwent second-look arthroscopy for persistent mechanical symptoms. Periosteal flap overgrowth was identified in 6 cases with adequate graft integration while partial failure of the graft was noted in one case and was treated with microfracture.

Conclusions: The early results of ACI in high-performance athletes and professional soldiers are not as good as other studies suggest. Returning to pre-injury performance levels for athletes and military people is by no means assured in the first 24 months after ACI.