Abstract
Objectives:
Bone-patellar tendon-bone (BPTB) autograft has been considered the gold standard graft source for young patients who wish to return to cutting or pivoting sports after anterior cruciate ligament reconstruction (ACLR). In the past decade, quadriceps tendon (QT) autografts have become increasingly popular due to the graft’s large cross-sectional area and potential for reduced graft site morbidity. However, current evidence on patient-reported outcome measures (PROMs), functional outcomes, and second ACL injury prevalence in patients who undergo ACLR with QT autograft is limited. In particular, there is a lack of large multi-site clinical studies comparing outcomes after ACLR with QT and BPTB autografts in young patients. Therefore, the purpose of this study was to compare PROMs, functional outcomes, and second ACL injury after ACLR with QT and BPTB autograft in patients from 13 to 30 years of age using available data from a large, multi-site patient registry.
Methods:
Data for this study were obtained from the ACL Reconstruction Rehabilitation Outcomes Workgroup (ARROW) multi-site registry, which includes data from 9 medical and academic center sites. Patients were 13-30 years of age, had undergone primary, unilateral ACLR, and had PROMs and functional outcome data collected 5-7 months after ACLR. Second injury data was collected at least 2 years after primary ACLR. PROMs included International Knee Documentation Committee (IKDC) score and ACL Return to Sport After Injury (ACL-RSI) score. The pediatric version of the IKDC was used for patients under 19 years of age. Functional outcome data was assessed bilaterally for isokinetic knee extension torque, isokinetic knee flexion torque, single leg hop distance, and triple hop distance. Limb symmetry indices (LSIs, %) were calculated for all functional outcomes. The association between graft source and prevalence of second injury was assessed using a binomial logistic regression while accounting for age and sex. Functional outcomes and PROMs were compared between graft sources using a one-way ANOVA.
Results:
730 patients (661 BPTB, 69 QT) were included in the analysis. QT and BPTB autograft cohorts did not differ in age (p = 0.392) or time since surgery (p = 0.598) (Table 1). Cohorts did not differ in IKDC score (p = 0.094), but QT autograft patients did report significantly lower ACL-RSI scores than BPTB autograft patients (p = 0.036) (Table 1). Isokinetic knee extension torque LSI (p = 0.272) and triple hop LSI (p = 0.074) did not differ between graft cohorts, but QT autograft patients reported significantly lower isokinetic knee flexion torque LSI (p = 0.042) and lower single hop LSI (p = 0.049) when compared to patients with BPTB autograft (Table 1). 91 BPTB autograft patients (13.8%) and 8 QT autograft patients (11.6%) experienced second ACL injury. When controlling for age and sex, graft source was not significantly associated with second ACL injury (p = 0.647, OR = 1.198, CI = 0.553-2.592).
Conclusions:
The current study was conducted using data from the ARROW registry and therefore included patients from multiple surgeons and multiple sites across the continental United States, making this study as representative as possible of the general young population. Graft source does not appear to be associated with second ACL injury at least two years after ACLR among patients 13 to 30 years of age with extensor mechanism grafts. However, patients with BPTB autograft reported better psychological readiness, hamstring strength, and single hop distance when compared to QT autograft patients. Future work should investigate the mechanisms by which BPTB autograft patients may be exhibiting improved ACL-RSI scores, flexion strength, and single hop distance, and how these differences 6 months post-ACLR may or may not impact long-term second ACL injury risk.
