Knee injury in adolescent dancers and acrobats

Dance and acrobatic gymnastics training often commences in childhood and intensifies during adolescence, increasing the risk of injury. The majority of injuries affect the lower extremity (LE) with patellofemoral pain syndrome (PFPS) identified as the most common cause of chronic knee pain in adolescent dancers. However, there has been no systematic synthesis of the data on risk factors for LE injuries in dancers and little research regarding acrobatic gymnastics injuries or factors associated with PFPS. A systematic review was conducted to investigate risk factors associated with LE injury in dancers. Increased hip abduction range was found to increase risk of knee and foot/ankle injuries. Body mass index, generalised joint hypermobility, age commenced dance and years of dance training were not risk factors for dance LE injury. A survey of 73 acrobatic gymnasts (aged 8-26 yrs) explored the prevalence and factors associated with acrobatic injury. The knee was the most common site of chronic injury (20%) with most reported as PFPS. Factors associated with injury included aged ≥13 years and training ≥8 hrs/wk at 11 years of age. A cross-sectional and cohort study investigated proprioceptive and kinematic factors associated with PFPS in adolescent dancers and acrobats. Participants with a history of PFPS exhibited decreased knee flexion range and a delay between peak angular velocity of ankle eversion and forefoot pronation when landing from a hop. There were no differences between groups in knee proprioception. Alterations in knee flexion and the timing of foot and ankle peak velocities when landing occur in dancers and acrobats with a history of PFPS. However, factors previously reported, such as excessive deviation of the knee into valgus alignment were not found to be associated with a history of PFPS. This finding may be due to the nature of dance and acrobatics training, in which balance and landing are key activities taught from the onset of training