Summary

The use of Quadriceps/patellar bone autograft has superior outcomes when compared to hamstring ACL reconstruction in adolescents

Abstract

Purpose

To compare outcomes of the quadriceps tendon patellar bone autograft (QPA) to the hamstring tendon autograft (HTA) in pediatric patients undergoing ACL reconstruction.

Methods

Following institutional review board approval, subjects who underwent primary ACL reconstructive surgery at our institution between 2005 and 2014 were identified through a query of ICD-9 diagnostic codes. All subjects meeting the inclusion criteria with a minimum of 12 months post-operation time were included. Subject charts were reviewed and subjects were contacted by phone or email when possible. Graft failure was defined as the need for revision surgery and/or MRI confirmation of graft failure. Multivariable cox proportional hazards regression analysis was used to compare the risk of graft failure in the two groups. Gender and number of procedures performed during the index surgery were included as potential confounding variables.

Results

The study population included 50 subjects in the QPA group (30 female, 20 male) and 46 subjects in the HTA group (18 female, 28 male). There were no significant differences in demographics between groups. The mean age at surgery for the QPA group was 15.3 years (stdev. ±2), the mean age of surgery for the HTA group was 15.7 years (stdev.± 1.5). However, there was a significant difference (p < 0.0001) between follow-up times for the two groups with 1.6 years for the QPA group (stdev. = 0.7) and 3.8 years for the HTA group (stdev. = 1.3). In the first 36 months after surgery, the estimated risk of failure in the HTA group was 2.9 [95% CI: 0.57 to 14.6, p = 0.1987] times the risk of graft failure in the QPA group. Comparing probability of survival over time (no graft failure) at 12 months, probability of survival was 100.0% for QPA and 91.3% for HTA; at 24 months, 96.2% for QPA and 86.7% HTA; at 36 months, 89.7% QPA and 84.3% HTA. Graft survival was higher in the QPA group compared to the HTA group at 12 months (100.0% vs 91.3%), 24 months (96.2% vs 86.7%), and 36 months (89.7% vs 84.3%). The short duration of follow-up (30/50 QPA patients were followed <36 months, compared to 5/46 in the HTA group) may bias survival estimates toward better survival in the QPA group and necessitates longer follow-up for further research.

Conclusion

Comparing graft failure rates for QPA versus HTA at 12, 24, and 36 months, the QPA trends toward more positive results than HTA.

Significance

As ACL ruptures become more common in the pediatric and adolescent population, determination of the best ACL reconstruction technique, which minimizes trauma to the physes, is imperative. This study suggests QPA may be a superior choice for ACL reconstruction in this population.