Background

The quadriceps tendon (QT) autograft is emerging as a popular choice in primary anterior cruciate ligament (ACL) reconstruction. As reported by the New Zealand ACL Registry, QT autograft use has increased from a proportion of 1% to 6% in yearly ACL reconstructions in the last 5 years. The trend continues to increase as QT autograft is used more commonly in New Zealand. To our knowledge, there has not been an Australasian study comparing patient reported outcome measures (PROMs) of QT with longstanding alternatives such as hamstring tendon (HT) and bone-patella-tendon-bone (BPTB) in primary ACL reconstruction. Therefore, this study aims to investigate differences in PROM scores and revision rates for QT in comparison with HT and BPTB in primary ACL reconstruction.

Methods

This study used prospectively collected data linked to the New Zealand ACL Registry. All patients who underwent a primary arthroscopic ACL reconstruction with a valid 12 month PROM score were considered for the study. Patients who had associated menisci injuries, multi-ligament knee injuries, revision without primary ACL reconstruction, non-arthroscopic ACL reconstruction, and previous ipsilateral knee surgery were excluded. Outcomes were grouped by the autograft used; QT, HT, and BPTB. The primary outcome measured was early PROM scores at 12 months post-surgery. PROM tools were standardised within the Registry, and included the MARX and Knee Injury and Osteoarthritis Outcome Score (KOOS) tools. Secondary outcomes measured were early revision rates, time to revision, and all cause for revision.

Study Design
Prospective cohort study; Level of evidence, 2.

Results

2019 patients were included in the study; 1570 in the HT group, 384 in the BPTB group, and 65 in the QT group. Baseline characteristics were comparable between the groups. With regards to 12 month MARX scores, no statistically significant difference was found between QT and HT (5.69 vs. 5.98, P = 0.618). However, a statistically significant difference was found between QT and BPTB (5.69 vs. 6.91, P = 0.047), and HT and BPTB (5.98 vs. 6.91, P < 0.001). No significant difference was found with regards to KOOS pain and quality of life scores. Low revision rates were found in all three groups, with no early revisions for the QT and BPTB groups and 4 revisions for the HT group.

Conclusions

QT had similar early PROM scores compared with HT, but both QT and HT had poorer functional outcomes compared with BPTB. Early revision rates were low irrespective of autograft choice. Although differences in PROM scores were small and may not be clinically significant, the results suggest that QT is a comparable autograft choice to the status quo for primary ACL reconstruction. Further research is required to understand the longer term outcomes of QT use in ACL reconstruction.