An Analysis of the Increased Risk for Lower Extremity Injury Within 12 Months After Concussion and Utilization of Lower Extremity Measures for Return to Sport

BACKGROUND: According to the Concussion Clinical Practice Guidelines, the typical recovery timeline post-concussion is about 7-14 days. However, recent research has shown an increased risk for lower extremity (LE) injury as early as 90 days and up to 1 year post-concussion. PURPOSE: The primary purpose of this study was to determine the prevalence of youth athletes who sustained a LE injury within 1 year post-concussion at Texas Children’s Hospital. The secondary purpose of this study was to describe the prevalence and utilization of LE functional testing performed by Physicians (MDs), Physical Therapists (PTs), and Athletic Trainers (ATs) as part of return to sport (RTS) clearance post-concussion. METHODS: A retrospective chart review was completed consisting of patients diagnosed with a concussion by a Sports Medicine Physician from September 2018 to September 2020. The inclusion criteria were as follows: male or female, ages 8-21, and active participation in 1 or more sports. The data was collected in Microsoft Forms. Additionally, a Microsoft Forms survey was sent to Sports Medicine MDs, PTs, and ATs to assess utilization of LE functional tests. SPSS 25.0 was used for analysis with alpha level at .05. A one-sample chi-square test was utilized to compare re-injury rate to the known rate of 1%. Other proportional comparisons were run using two-sample chi-square analyses. RESULTS: A total of 635 charts were reviewed with 527 patients participating in at least 1 sport. 12.7% (N=54) of those who sustained a concussion had either a musculoskeletal injury or another concussion within 1 year, with the highest proportion of injuries being a second concussion (33.3%) or ligament sprain (35.2%). Of the providers polled, 52.8% do not currently use a LE functional measure as part of RTS criteria. The most commonly reported reasons that providers do not use LE measures were as follows: not included in their standard of practice, lack of time, and lack of knowledge. CONCLUSION: The results suggest a LE test battery may be beneficial to assess LE injury risk post-concussion. Additionally, the majority of providers do not currently use LE functional measures when assessing RTS criteria. Considering the increased risk for LE injury and lack of LE functional testing completed by providers, further education about current, available LE functional testing should be provided to decrease the prevalence of LE injury after concussion. Future studies should analyze the effects of LE strengthening and functional testing on subsequent LE injury risk post-concussion.