Background: Functional instability after anterior cruciate ligament injury can be successfully treated with ligament reconstruction. However, the associated meniscus and cartilage lesions often cannot be repaired and may have long-term detrimental effects on knee function.
Purpose: The authors used the large database within the Kaiser Permanente Anterior Cruciate Ligament Reconstruction Registry to evaluate time to surgery, age, and gender as risk factors for meniscus and cartilage injury and associations with meniscus repair rates in patients.
Study design: Cross-sectional study; Level of evidence, 3.
Methods: A retrospective review of the Kaiser Permanente Anterior Cruciate Ligament Reconstruction Registry was performed. The associations between time to surgery, age, and gender with meniscus and cartilage lesions and meniscus repair were analyzed using binary logistic regression modeling to calculate odds ratios (ORs) while adjusting for potential confounding variables.
Results: A total of 1252 patients met the inclusion criteria. The risk of medial meniscus injury increased only with time to surgery (6-12 months: OR = 1.81, 95% confidence internal [CI] 1.29-2.54, P = .001; and >12 months: OR = 2.19, 95% CI 1.58-3.02, P < .001). The risk of lateral meniscus injury decreased only with female gender (OR = 0.65, 95% CI 0.51-0.83, P = .001). The risk of cartilage injury increased with age (OR = 1.05 per year, 95% CI 1.04-1.07, P < .001) and time to surgery >12 months (OR = 1.57, 95% CI 1.12-2.20, P = .009), but decreased with female gender (OR = 0.71, 95% CI 0.54-0.92, P = .009). Medial meniscus repairs relative to medial meniscus injury decreased with increasing time to surgery (3-6 months: OR = 0.61, 95% CI 0.37-1.00, P = .050; and >12 months: OR = 0.41, 95% CI 0.25-0.67, P < .001) and increasing age (OR = 0.96 per year, 95% CI 0.94-0.98, P < .001).
Conclusion: Increased risk of medial meniscus injury and decreased repair rate were strongly associated with increasing time to surgery. Increased risk of cartilage injury was associated with increasing age, increasing time to surgery, and male gender.