Summary

At minimum 10 year follow up, patients with revision ACL reconstruction scored significantly worse on the subjective SANE scale than in primary reconstruction, but did not have a greater likelihood of unsatisfactory patient-reported outcome or activity scores.

Abstract

Introduction

Anterior cruciate ligament (ACL) reconstruction is commonly performed in athletes involved in sports that require pivoting movements of the knee, with failure rates reported to be as low as 5% and as high as 34% in athletes. Graft survival rates for revisions, although quite high, are lower than primary procedures, and may impact athletes’ ability to return to pre-injury sporting levels, as well as their long-term health. The purpose of this study was to report on long term outcomes and compare patient-reported outcomes measures (PROMs) between primary and revision ACL surgery.

Methods

Patients who had undergone primary or revision ACL reconstruction at our institution between 2008 and 2013 were contacted and surveyed with the Marx Activity Rating Scale (MARS), International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC-SKEF), the PROMIS-10 Global Health Questionnaire, the Tegner Activity Scale, and the Single Assessment Numeric Evaluation (SANE). Demographic information, as well as information regarding subsequent surgery or diagnoses were collected. We defined patients as “unsatisfactory” when they did not achieve an IKDC score of 75, which has been previously defined as a threshold value for the Patient-Acceptable Symptom State (PASS). PROMs and the presence of subsequent surgery or diagnoses were compared between primary versus revision ACL reconstructions were compared in terms of outcomes, and odds ratios were calculated and compared using Chi- Square Tests.

Results

241 patients were included in this study. The average time to follow-up was 11.9±1.7 years. 228 patients had a primary ACL reconstruction and 13 had a revision ACL reconstruction, 9 of whom had an allograft implanted at the time of revision. Average age at the time of reconstruction was 38.4±12.7 years. None of these patients had a re-revision. At follow-up, revision ACL patients scored lower on all outcome measures analyzed, and this was statistically significant for the SANE score (primary=82.6, revision=68.8; p=0.02). After controlling for other factors such as age at surgery, graft type, and sex, we found that revision ACL reconstruction was a significant predictor of lower SANE scores (p=0.014). However, we found that patients who had a revision procedure did not have significantly different odds of scoring lower than 75 on the IKDC-SKEF than patients who had a primary ACL reconstruction (OR=1.04 [0.27, 3.39]; p= 0.96]. Furthermore, no significant differences in the odds of having any subsequent knee diagnosis, an ACL re-tear, or procedure were found.

Conclusions

At minimum 10 year follow up, patients with revision ACL reconstruction scored significantly worse on the subjective SANE scale than in primary reconstruction. However, the patients in the revision cohort did not have a greater likelihood of unsatisfactory patient-reported outcome or activity scores. Further long-term studies are needed to understand the factors related to lasting success after revision ACL reconstruction.