LAUSR

Objective To analyze the MRI manifestations of and factors related to ankle injuries in asymptomatic amateur marathon runners. Materials and methods A total of 113 amateur marathon runners without any ankle joint symptoms were recruited. Each participant was asked to complete a questionnaire at the beginning of the study and underwent MRI of the ankle. The MRI manifestations of ankle injuries were summarized, and binary logistic regression analysis was applied to analyze the factors related to ankle injuries. Results The main MRI features were bone marrow edema-like signal intensity, peritendinous effusion, and partial lateral collateral ligament injury. Others included Achilles tendinopathy, cyst-like lesions, osteochondral lesions, and subcutaneous soft tissue edema. The risk factor for bone marrow edema-like signal intensity in amateur marathon runners was a rearfoot strike pattern ( p  = 0.028, OR = 1.172); the risk factors for peritendinous effusion were a higher weekly running distance ( p  = 0.013, OR = 1.685) and increased running years ( p  = 0.039, OR = 1.113), whereas a rearfoot strike pattern ( p  = 0.005, OR = 0.831) was a protective factor for peritendinous effusion; the risk factor for Achilles tendinopathy was increased age ( p  = 0.008, OR = 1.412); the risk factors for anterior talofibular ligament injury were a rearfoot strike pattern ( p  = 0.017, OR = 1.346) and higher weekly running distance ( p  = 0.022, OR = 1.171); and the factors for calcaneofibular ligament injury were a higher weekly running distance ( p  = 0.029, OR = 1.570) and rearfoot strike pattern ( p  = 0.035, OR = 1.463). Conclusion The main MRI features of asymptomatic amateur marathon runners are bone marrow edema-like signal intensity, peritendinous effusion, and partial lateral collateral ligament injury. In addition, increased age, increased running years, higher weekly running distance, and different foot strike patterns are risk factors for ankle injuries.