Time from ACL injury to reconstruction and the prevalence of additional intra-articular pathology: is patient age an important factor?

PURPOSE: Meniscus and cartilage lesions have been reported to be prevalent during delayed reconstruction of anterior cruciate ligament (ACL) injuries. Relatively, little work has been done exploring the influence of patient age on this relationship. The purpose of this study is to determine whether the effect of time from ACL injury to reconstruction on the prevalence of associated meniscal and chondral injury is influenced by patient age. It was hypothesized that patients in whom the time from ACL injury to reconstruction exceeds 12 weeks will exhibit an increased prevalence of medial compartment pathology relative to those reconstructed within 12 weeks of injury in patients of all ages.

METHODS: Data detailing time from ACL injury to reconstruction and the prevalence of intra-articular findings were obtained in 311 of 489 consecutive patients undergoing primary isolated ACL reconstruction. Patients were divided into two groups based on whether the time from ACL injury to reconstruction was <12 weeks or at least 12 weeks. The prevalence of associated intra-articular injury was then compared between the two groups. Patients were then stratified based on age (22 years and under vs. over the age of 22), and the analysis was repeated on both groups.

RESULTS: Analysis of all patients together revealed a significantly higher prevalence of medial meniscus injury (p = 0.013) and medial compartment chondral injury (p < 0.0005) in patients in whom the time from ACL injury to reconstruction exceeded 12 weeks. The prevalence of lateral meniscal injury did not increase with increasing time ACL injury to surgery. Among patients aged 22 years and under, there was no increase in the prevalence of intra-articular pathology in any compartment in the late reconstruction group. In contrast, among patients over the age of 22, there was a significant increase in the prevalence of medial chondral injury (p = 0.042) in the late reconstruction group.

CONCLUSION: The prevalence of injuries to the meniscus and articular cartilage in the medial compartment of the knee is increased with increasing time from ACL injury to reconstruction. This relationship may vary depending on patient age. Patients over the age of 22 exhibit a higher prevalence of intra-articular injury with delayed reconstruction, while no such differences are noted among younger patients.

LEVEL OF EVIDENCE: Retrospective comparative study, level III.