Background
Revision anterior cruciate ligament (ACL) reconstruction has been documented to have worse outcomes compared with primary ACL reconstructions. The reasons why remain varied. The purpose of this study was to determine whether previous or current surgical factors noted at the time of revision ACL reconstruction are significant predictors towards activity level, sports function, and osteoarthritis (OA) symptoms at 2-year follow-up.
Hypothesis
Certain factors under the control of the surgeonat the time of revision surgery can both negatively and positively impact outcome.
Study Design
Cohort Study; Level of evidence, 2.
Methods
Revision ACL reconstruction patients were identified and prospectively enrolled between 2006 and 2011. Data collected included baseline demographics, intra-operative surgical technique and joint pathology, and a series of validated patient-reported outcome instruments (International Knee Documentation Committee [IKDC], Knee Injury and Osteoarthritis Outcome Score [KOOS], Western Ontario McMaster Universities Osteoarthritis Index [WOMAC], and Marx activity rating score) completed prior to surgery. Patients were followed up for 2 years, and asked to complete the identical set of outcome instruments.
Regression analysis was used to control for age, gender, body mass index (BMI), activity level, baseline outcome scores, revision number, time since last ACL reconstruction, and a variety of previous and current surgical variables, in order to assess the surgical risk factors for clinical outcomes 2 years after revision ACL reconstruction.
Results
A total of 1205 patients (697 [58%] males) met the inclusion criteria and were successfully enrolled. The median age was 26 years, and median time since their last ACL reconstruction was 3.4 years.
Two-year follow-up was obtained on 82% (989/1205). Both previous as well as current surgical factors were found to be significant contributors towards poorer clinical outcomes at 2 years. The most consistent surgical factors driving outcome in revision patients were prior surgical approach (arthrotomy vs. no arthrotomy), prior tibial tunnel position, femoral fixation at the time of revision, and having a notchplasty. Having a previous arthrotomy (non-arthroscopic open approach) for ACL reconstruction compared to the one-incision technique resulted in significantly poorer outcomes on 2-year IKDC (p=0.037; odds ratio[OR]=2.43; 95% CI, 1.05–5.88) and KOOS pain, sports/rec, and quality of life (QOL) subscales (p≤0.05; OR range=2.38–4.35; 95% CI, 1.03–10.0). Using a metal interference screw for current femoral fixation resulted in significantly better outcomes in 2-year KOOS symptoms, pain, and QOL subscales (p≤0.05; OR range=1.70–1.96; 95% CI, 1.00–3.33), as well as WOMAC stiffness (p=0.041; OR=1.75; 95% CI, 1.02–3.03). Not having a notchplasty at revision significantly improved 2-year outcomes of the IKDC (p=0.013; OR=1.47; 95% CI, 1.08–1.99), KOOS activities of daily living (ADL) and QOL subscales (p≤0.04; OR range=1.40–1.41; 95% CI, 1.03–1.93)...