Poster 197: Risk of Revision and Reoperation after ACL Reconstruction. Comparison of Quadriceps Tendon,Patellar Tendon,and Hamstring Autografts Stratified by Patient Gender and Age: A cohort study of 27,715 Patients

Abstract

Objectives:

The purpose of this study was to evaluate risk for subsequent surgical outcomes, including revision and reoperation, for a cohort of primary anterior cruciate ligament reconstruction (ACLR) patients according to autograft selection stratified by patient gender and age.

Methods:

Data from a US healthcare system’s ACLR registry was used to conduct a cohort study. 27,715 primary isolated autograft ACLR patients were identified (2012-2023); those with prior procedures in the same knee were excluded. The exposure of interest autograft type: quadriceps tendon (QT), bone-patellar tendon-bone (PT), and hamstring tendons (HT). Multivariable Cox proportional hazard regression models were used to evaluate the risk for revision and risk for ipsilateral reoperation according to autograft selection. Age, body mass index, gender, race/ethnicity, American Society of Anesthesiologist’s classification, activity at the time of injury, prior contralateral ACLR, cartilage injury, lateral meniscus injury, medial meniscus injury, femoral tunnel drilling technique, operative time, and operative year were considered as covariates in regression analysis; models also included a cluster term for operating surgeon to account for correlation of ACLR performed by the same surgeon. Hazard ratios (HR) and 95% confidence intervals are reported, a p<0.05 the threshold for statistical significance. Secondary analysis restricted to patients who were <22 years at the time of their ACLR.

Results:

The study sample comprised 27,715 ACLR. There were 10,955 females and 16,760 males who underwent primary isolated ACLR; procedures were performed by 319 surgeons at 58 hospitals.

In the female cohort, QT, PT, and HT autograft were used in 874 (8.0%), 4597 (42.0%), and 5484 (50.1%) ACLR, respectively. Figure 1 presents the cumulative incidence of revision (top panel) and reoperation (bottom panel) during 5-years follow-up by graft type; number of patients still at risk for each year of follow-up is presented along the x-axis. In adjusted models, no significant differences were observed in revision risk (HR=0.72, 95% CI=0.35-1.49, p=0.375) or reoperation risk (HR=0.84, 95% CI=0.58-1.21, p=0.344) when comparing QT to PT ACLR. However, QT ACLR had a lower revision risk (HR=0.41, 95% CI=0.22-0.77, p=0.006) compared to HT ACLR; no differences were observed for reoperation (HR=0.95, 95% CI=0.65-1.38, p=0.787). HT ACLR were noted to have a higher risk of revision (HR=1.76, 95% CI=1.36-2.29, p<0.001) compared to PT and no difference in reoperation risk (HR=0.89, 95% CI=0.75-1.05, p=0.167). Similar findings were observed when restricting to patients aged <22 years (Table 1).

There were 1297 (7.7%) QT, 7560 (45.1%) PT, and 7903 (47.2%) HT ACLR performed in male patients. Figure 2 presents the cumulative incidence of revision (top panel) and reoperation (bottom panel) during follow-up by graft type for males; number of patients still at risk for each year of follow-up is presented along the x-axis. No differences in revision or reoperation risk were observed when comparing QT to PT (revision: HR=0.98, 95% CI=0.60-1.60, p=0.936; reoperation: HR=1.15, 95% CI=0.74-1.78, p=0.526) or HT ACLR (revision: HR=0.70, 95% CI=0.47-1.04, p=0.074; reoperation: HR=1.34, 95% CI=0.92-1.93, p=0.123). While HT ACLR associated with a higher revision risk compared to PT ACLR (HR=1.32, 95% CI=1.08-1.61, p=0.008), no difference was observed in reoperation risk (HR=0.88, 95% CI=0.74-1.04, p=0.132). Similar findings were observed when restricting to patients aged <22 years (Table 2).

Conclusions:

In females, a 1.8X higher risk of revision was identified when HT ACLR was compared to PT, and a 2.4X higher risk of revision when HT was compared to QT. In males, a 1.3 X higher risk of revision was identified when HT was compared to PT. No differences in risk of revision were noted when QT was compared to PT ACLR. Surgeons should consider this data when discussing risks and benefits of the different graft options for ACLR, especially with their female patients.