Abstract: BACKGROUND: Multiple ligament injuries of the knee are a complicated problem, which is prone to vascular and nerve damage, leading to severe dysfunction. However, for the current surgical treatment of knee dislocation and multiple ligament injuries, there is a lack of effective evaluation on the timing of surgery and postoperative gait. 
OBJECTIVE: To investigate the clinical effect of stage I arthroscopic repair and reconstruction in patients with multiple ligament injuries of the knee joint, and provide a reference for clinical guidance of functional exercises after multiple ligament injuries of the knee joint through a three-dimensional gait analysis. 
METHODS: The clinical data of 15 patients with multiple ligament injury of knee dislocation who were treated in the First Affiliated Hospital of Kunming Medical University from September 2014 to August 2018 were collected. All the cases were single knee injury, including 11 males and 4 females. Their age ranged from 18 to 40 years old, with an average of (28±8) years old. The time from injury to operation was 10-18 days, with an average of 14 days. At admission, the anterior and posterior drawer tests and the Lachman test were positive in all the patients. The knee varus stress test was positive in eight patients, and the knee valgus stress test was positive in five patients. Lysholm knee joint function score was (27.85±5.98) points, and joint range of motion was (49.15±13.47)°. Under arthroscopy, autologous hamstring tendons were taken to reconstruct the anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament, and other injured knee joint structures. The range of knee joint motion and Lysholm score were evaluated, and three-dimensional gait analysis was conducted postoperatively.
RESULTS AND CONCLUSION: Grade I/A healing was found in 15 patients. All patients were followed up for 11-24 months. During the postoperative follow-up, all patients had negative results in the anterior and posterior drawer tests and in the knee varus and valgus stress tests. Lysholm knee function score and joint range of motion of the affected limb were significantly improved at the last follow-up after repair, which were (85.3±6.65) points and (122.83±9.27)°, respectively, significantly different from the preoperative levels (t=24.879, P=0.000; t=17.452, P=0.000). Results of kinematic analysis showed that there were no significant differences in varus and valgus angles, internal and external displacements, internal and external rotations, flexion and extension angles, up and down displacements, and anteroposterior displacements between the healthy and affected limbs in the gait analysis at the last follow-up (P > 0.05). All these findings indicate that stage I arthroscopic repair of multiple ligament injuries of the knee joint can restore the stability of the knee joint, which is a safe, reliable, and effective treatment.

Key words: knee dislocation with multiple ligament injuries, arthroscopy, repair and reconstruction, three-dimensional gait analysis, Lysholm score