Beyond the ligament: Role of bone bruising patterns and their clinical impact in acute ACL injuries
Background: Bone marrow edema (BME) is one of the common magnetic resonance imaging (MRI) findings in anterior cruciate ligament injuries. The prevalence and clinical relevance of BME vary depending on injury mechanism and timing of imaging. This study aimed to evaluate the prevalence and patterns of BME in patients with ACL tears and to correlate these patterns with mechanism of injury. Methods: In this hospital based observational study, a total of 136 patients with MRI confirmed ACL injuries were included. MRI of the affected knee was performed using standardized hospital protocols. BME patterns were categorized into pivot-shift, hyperextension, varus or valgus stress and mixed patterns. MRI findings were correlated with patient reported mechanism of injury. Results: Bone marrow edema was detected in 63 (46.3%) patients. Among 63 patients with bone marrow edema, pivot-shift pattern of bone marrow edema was the most frequently observed MRI findings seen in 29 (46.0%) patients, followed by hyperextension pattern identified in 14 (22.2%) patients. Pivot-shift pattern was predominantly associated with sports injuries seen in 21 (29.2%) patients, while hyperextension were more commonly observed followed by road traffic accidents seen in 7 (21.9%) patients. Varus, valgus and mixed patterns were frequently seen in fall and twisting injuries. A statistically significant association was observed between bone marrow edema ptterns and reported mechanism of injury (x2 = 28.4, p = 0.003). Conclusion: Systematic BME pattern analysis into routine MRI reporting may enhance diagnostic accuracy, improve clinical decision-making, and contribute to more individualized patient management strategies following ACL injury.