The aims to evaluate the effectiveness of dislocated and unstable knee joint reconstruction using calcanei combined with an Achilles tendon allograft using one-stage arthroscopy. From January 2008 to January 2010, we treated 11 patients with knee-joint dislocation using calcanei combined with an Achilles tendon allograft using one-stage arthroscopy. A total of 9 males and 2 females aged 17 years to 45 years (average age of 22.3 years) were included in this study. All patients were treated with calcanei combined with an Achilles tendon allograft. The posterior cruciate, medial collateral, anterior cruciate and lateral collateral ligaments were reconstructed. All incisions healed at the first follow-up two weeks after operation. Ten of the patients were monitored for 24 months to 36 months (average of 30 months). Kneejoint function was evaluated using Lysholm and International Knee Documentation Committee scores. Significant differences were found between the pre- and post-operation Lysholm and IKDC scores (P<0.05), as well as between the pre- and post-operation movement ranges (P<0.05). The application of calcanei combined with an Achilles tendon allograft for the treatment of dislocated knee joints using one-stage arthroscopy recovered the stability and movement range of the knee joint. Therefore, the proposed method leads to satisfactory clinical effects.