Incidence and Characteristics of Meniscal Injuries in Cadets at a Military School, 2013-2015

Context: Meniscal injury is common among military service members. Objective: To examine the incidence and characteristics of meniscal injuries in cadets at a single military institution between 2013 and 2015. Design: Cohort study. Setting: Meniscal-injury data were collected at the Center of Rehabilitation Training, the People's Liberation Army University of Science and Technology. Patients or Other Participants: A total of 2479 cadets participating in physical activities between 2013 and 2015. Main Outcome Measure(s): Injury rates, injury proportions by body mass index, risk ratios (RRs), and injury proportion ratios were reported with 95% confidence intervals (CIs). Results: The overall incidence rate was 10.08 (95% CI = 6.84, 14.84) per 1000 person-years. A multiple-comparisons test revealed differences in the relative injury rate in overweight or obese cadets versus normal-weight cadets and underweight cadets (chi(2) = 8.98, P = .01). No differences were found between injured normal-weight cadets and underweight cadets (P = .66, RR = 1.39, 95% CI = 0.32, 6.06) or between injured overweight or obese cadets and injured underweight cadets (P = .24, RR = 0.42, 95% CI = 0.09, 1.91). The absolute injury rate was higher for overweight and obese cadets compared with normal-weight cadets (P < .01, RR = 0.30, 95% CI = 0.13, 0.69). The overall proportional distribution for patterns of injury was 2: 1 (medial to lateral) for meniscal injuries. Grade 2 injuries were the most common. Conclusions: The high frequency and level of severity of meniscal injuries may negatively affect the readiness and health of cadets. High body mass index was a risk factor for meniscal injury.