RESUMEN
Objective:To explore the clinical outcomes of intraoperative fluoroscopy on femoral tunnel placement in treating professional snow sports athletes with anterior cruciate ligament (ACL) injury.Methods:A retrospective case series study was used to analyze the clinical data of 13 professional snow sports athletes with ACL injury treated in the National Institute of Sports Medicine, General Administration of Sport of China from January 2016 to January 2019. There were 5 males and 8 females, aged 16-27 years [(18.5±3.0)years]. Intraoperative lateral fluoroscopy combined with quadrant method was performed for the accurate femoral tunnel placement in single-bundle ACL reconstruction by using autologous hamstring tendon in all patients. KT1000 side-to-side difference (KT1000-ssd), pivot shift test, International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Marx activity scale and maximum extension and flexion resistance ratio of the involved and uninvolved knee were compared before operation (or before injury) and at 3, 6, 12 and 24 months after operation. Whether returning to the field, time taken in returning to the field and re-injury were recorded at each follow-up visit. ACL graft signal intensity ratio (SIR) in MRI of the involved knee was evaluated at postoperative 24 months.Results:All patients were followed up for 24-33 months [(25.8±2.7)months]. There were 7 patients with KT1000-ssd degree I, 5 with degree II and 1 with degree III before operation, compared to 12 patients with KT1000-ssd degree 0 and 1 with degree I at 3 and 6 months after operation and 13 patients with KT1000-ssd degree 0 at 12 and 24 months after operation. The pivot shift test was grade I in 8 patients and grade II in 5 before operation, compared to 11 patients with degree 0 and 2 with degree I at 3 months after operation and 12 patients with degree 0 and 1 with degree I at 6, 12 and 24 months after operation. IKDC subjective score was (68.0±4.3)points, (84.7±7.9)points, (94.6±3.3)points and (96.5±1.8)points at postoperative 3, 6, 12 and 24 months, respectively. Six months after operation, IKDC subjective score was significantly improved compared to the preoperative (48.3±25.0)points (all P<0.01). The Lysholm score was (63.4±6.6)points, (80.1±6.5)points, (93.8±4.6)points and (96.5±2.4)points at postoperative 3, 6, 12 and 24 months, respectively. Six months after operation, the Lysholm score was significantly improved compared to the preoperative (47.5±29.4)points (all P<0.01). The Marx activity scale was (7.4±0.5)points, (13.8±0.7)points, (14.6±0.8)points and (15.0±0.7)points at postoperative 3, 6, 12 and 24 months, respectively, significantly lower than (16.0±0.0)points before the injury (all P<0.01). The maximum extension resistance ratio of the involved and uninvolved knee was 0.60±0.10, 0.85±0.08, 0.91±0.06 and 0.97±0.04 at postoperative 3, 6, 12 and 24 months, respectively. Six months after operation, the maximum extension resistance ratio of the involved and uninvolved knee was significantly increased compared to the preoperative 0.57±0.18 (all P<0.01).The maximum flexion resistance ratios of involved and uninvolved knee were 0.64±0.09, 0.82±0.06, 0.89±0.04 and 0.94±0.06 at postoperative 3, 6, 12 and 24 months, respectively. Six months after operation, the maximum flexion resistance ratio of the involved and uninvolved knee was significantly increased compared to the preoperative 0.60±0.12 (all P<0.01). Thirteen athletes returned to the field within 12 months after operation with the time taken in returning to the field ranging from 5-12 months [(8.7±1.9)months]. There was no ACL re-injury at postoperative 24 months. The ACL graft SIR in MRI of the involved knee was 1.80±0.20 at postoperative 24 months. Conclusion:Intraoperative fluoroscopy on femoral tunnel placement in the treatment of professional snow sports athletes with ACL injury can significantly improve the knee joint stability, subjective function, sports performance and muscle strength within 6 months, and can help them return to the field within 12 months, and accelerates graft healing.