Epidemiology With Video Analysis of Knee Injuries in the Women’s National Basketball Association

BACKGROUND: Knee injuries are the most common type of injury seen in the Women’s National Basketball Association (WNBA). However, there are sparse epidemiologic data regarding these injuries over the past 20 years. PURPOSE/HYPOTHESIS: The purpose of this study was to determine the prevalence, return to play (RTP) rate/length, and mechanism of knee injuries in the WNBA. We hypothesized that anterior cruciate ligament (ACL) tears would have the highest prevalence and longest RTP times. STUDY DESIGN: Descriptive epidemiology study. METHODS: Publicly available WNBA injury reports were used to find WNBA athletes who sustained knee injuries. The RTP length was determined by calculating the number of days between the date of the injury and the date of the first game they played after returning. The RTP rate was determined by calculating the number of players who returned to play from each injury compared with the total number of each injury. Incidence of knee injuries, frequency, and time to RTP were calculated for each injury. Available videos were analyzed to determine the mechanism and body position at the time of injury. RESULTS: Overall, 99 WNBA players were identified as having sustained a knee injury during the study period resulting in loss of play. ACL tears (n = 37; 37%) were the most devastating injury, resulting in the longest time before RTP (n = 375 days; 70%). The position with the highest incidence of knee injuries was guard, accounting for 53% of knee injuries. Video analysis conducted on 12 knee injuries revealed that such injuries were most commonly noncontact (83%).The mechanisms of injury were most commonly planting (58%) and landing from a jump (33%) with the knee flexed in the valgus position (100%). CONCLUSION: Study findings indicated that ACL tears are the most common clinically significant knee injuries sustained in the WNBA, accounting for 37% of total knee injuries with a mean RTP rate of 375 days. The most common mechanism of injury was planting the foot or landing from a jump with a flexed knee in the valgus position. Knee injuries had a high RTP rate in WNBA players but resulted in them missing a significant amount of playing time.