title: Concussion Frequency Associates with Musculoskeletal Injury in Retired NFL Players.
abstract: OBJECTIVE
  Concussion is commonly associated with immediate and persistent alterations in motor function affecting postural control and gait. Patients with lower extremity joint injury have demonstrated functional alterations in the cerebral cortex, suggesting that musculoskeletal injury may be linked to alterations in brain function. Therefore, we examined the associations between concussion frequency and lower extremity musculoskeletal injury sustained during professional careers of National Football League (NFL) players in a cross-sectional study.
  
  
  METHODS
  An inclusive health history survey was mailed to 3647 NFL players who retired during 1930-2001. Respondents reported total concussion frequency (zero, one, two, or three or more) and presence (yes/no) of specific knee and ankle musculoskeletal injury during their NFL career. Separate logistic regression models were used to estimate associations between concussion frequency and each musculoskeletal injury type, adjusting for number of years played in the NFL, body mass index while playing in the NFL, and playing position.
  
  
  RESULTS
  Data from 2429 players (66.6% response rate) were available for analysis. Nearly 61% reported experiencing a concussion while competing in the NFL. Meniscal tear was the most commonly reported musculoskeletal injury (32%). Compared with NFL players who did not sustain a concussion, retired NFL players with one, two, or three or more concussions had between 18% and 63%, 15% and 126%, and 73% and 165% higher odds of reporting various musculoskeletal injuries, respectively.
  
  
  CONCLUSIONS
  A history of concussions was associated with a history of musculoskeletal injuries during NFL careers. These data suggest that a higher number of concussions is linked with higher odds of reporting a musculoskeletal injury.
authors: 1Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, NC; 2Neuromuscular Research Laboratory, University of North Carolina at Chapel Hill, Chapel Hill, NC; 3Sports Medicine Research Laboratory, University of North Carolina at Chapel Hill, Chapel Hill, NC; 4Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC; 5Thurston Arthritis Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC; 6Injury Prevention Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC; 7Matthew Gfeller Sport-Related Traumatic Brain Injury Research Center, University of North Carolina at Chapel Hill, Chapel Hill, NC; and 8Center for the Study of Retired Athletes, University of North Carolina at Chapel Hill, Chapel Hill, NC.
authors: Brian
authors: B
authors: Pietrosimone
authors: Yvonne M
authors: YM
authors: Golightly
authors: Jason P
authors: JP
authors: Mihalik
authors: Kevin M
authors: KM
authors: Guskiewicz
mesh_terms: D016512:Ankle Injuries / Q000150:complications; D001924:Brain Concussion / Q000150:complications*; D003430:Cross-Sectional Studies; D018409:Foot Injuries / Q000150:complications; D005538:Football / Q000293:injuries*; D006801:Humans; D007718:Knee Injuries / Q000150:complications; D035002:Lower Extremity / Q000293:injuries*; D008297:Male; D009141:Musculoskeletal System / Q000293:injuries*; D012307:Risk Factors