Incidence of Secondary Intra-articular Injuries With Time to Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Precise locations of chondral and meniscal damage with increased time to anterior cruciate ligament reconstruction (ACLR) have not been well described.

PURPOSE/HYPOTHESIS: The purpose of the study was to determine the relationship between delay in primary ACLR and incidence of secondary intra-articular injury. The hypothesis was that patients with increased time between initial injury and ACLR will exhibit greater incidence of secondary intra-articular injury when compared with those who receive surgical intervention promptly after injury. A second hypothesis was that patients with higher preinjury activity levels or older age will exhibit greater secondary injury when compared with those with minimal preinjury activity levels and younger age.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: A retrospective review was performed on 1434 patients with an anterior cruciate ligament deficiency who underwent primary ACLR at a single institution between 2009 and 2013. Patients were grouped according to time to surgery after initial injury: 0-3, 4-12, and >12 months. Operative notes were used to analyze 10 variables across time-to-surgery groups: cartilage damage in the patella, trochlea, medial femoral condyle, lateral femoral condyle, medial tibial plateau, and lateral tibial plateau; medial and lateral meniscal injury; and the incidence of procedures involving either the meniscus or cartilage. Patient age and preinjury activity level were also analyzed for the 10 variables based on time-to-surgery groups.

RESULTS: An association was noted between time to surgery and increased incidence of injury in the trochlea, lateral femoral condyle, medial tibial plateau, and medial meniscus (P < .001). Different significant findings within each age group were observed, but overall positive findings were seen in the same 4 locations described above. On the basis of preinjury activity level, the less active patients were most at risk for medial meniscal and trochlear injury, while the more active patients were most at risk for medial tibial plateau injury with increased time from injury to ACLR.

CONCLUSION: Increasing time from injury to ACLR was associated with increased incidence of secondary injury seen in the trochlea, lateral femoral condyle, medial tibial plateau, and medial meniscus. Separate analyses of patient age and preinjury activity level showed similar findings, thus supporting the primary analysis.