Paper 23: The Impact of Graft Choice on Return to Sport Testing After Adolescent ACL Reconstruction

OBJECTIVES: The number of anterior cruciate ligament (ACL) injuries and reconstructions observed in the adolescent population continues to rise. While the use of quadriceps tendon autograft has increased in popularity in this population, there remains no consensus on the ideal graft for pediatric ACL reconstruction. The objective of this study was to compare three commonly used ACL graft types with respect to i) performance on return to sport assessments and ii) timing to clearance for return to sports in an adolescent population. METHODS: All patients, less than or equal to 19 years of age, who underwent reconstruction for ACL tears between 2016 and 2020 at a large, urban, academic institution were identified. Graft choice was made in a shared decision-making model with patient, parents, and surgeon. Patient demographics, laterality, graft type, time from surgery to clearance, number of physical therapy (PT) visits, and presence of concomitant meniscus injuries were collected from the electronic medical record. At a minimum of 6 months postoperatively, patients completed a formal return to sport test (RTS) including isometric strength assessments, Y- balance testing, and hop testing. Treatment cohorts based on graft type were compared with respect to RTS performance and timing to clearance. Associations between patient demographics and return to sport timing and performance were also assessed. Clearance for return to sport was determined by the treating surgeon with limb symmetry index of 90% on RTS as the goal for clearance. RESULTS: A total of 110 adolescents, 44 female (40%), with a mean age of 16.3 years (SD, 1.7; range, 10-19) met our inclusion criteria (Table 1). Average time to first RTS assessment was 280 days (9.3 months) and average time to clearance was 371 days (12.2 months) after surgery. ACL grafts included 58 (52.7%) hamstring autografts, 26 (23.6%) bone-patellar tendon-bone (BPTB) autografts, 21 (19.1%) bone quadriceps (BQT) autografts, and 5 (4.6%) iliotibial band (ITB) autografts. ITB patients were younger on average (12.5 years old) than those receiving hamstring, BPTB or BQT grafts. There were no significant differences between groups with respect to laterality, number of physical therapy visits, or rate of concurrent meniscus surgery. Patients receiving BQT grafts were more likely to be cleared within 1 year of surgery compared to hamstring graft patients (82.4% vs. 39.6%, p=0.002) and had similar rates of clearance within 1 year compared to BPTB patients (82.4% vs. 65.2%, p=0.230). Patients with BQT and BPTB grafts both demonstrated significantly better hamstring strength symmetry compared to hamstring graft patients (5.8% strength deficit compared to healthy side vs. 1.3% vs. 29.3%, p<0.001) (Table 2). There were no differences in quadriceps strength or hop test asymmetry between graft types. Multivariate regression with age, gender, and number of PT sessions included as covariates demonstrated that hamstring graft choice was associated with decreased odds of clearance at 1 year. CONCLUSIONS: In this study of 110 adolescent ACL reconstruction patients who underwent return to sport evaluations, we found no significant difference between BPTB and BQT autografts with respect to RTS performance and time to clearance. Hamstring autograft was associated with significantly worse hamstring strength asymmetry and significantly lower rates of clearance within 1 year. Concurrent meniscus surgery, age, gender, and number of PT sessions completed prior to RTS evaluation were not significantly associated with timing of clearance or performance on the RTS assessment.