The brain is a long way from the ankle, and yet concussions appear to be positively correlated with lower extremity injury. Coincident or causative? A new study of concussed National Basketball Association athletes presented at the 2021 American Academy of Orthopaedic Surgeons (AAOS) annual meeting in San Diego, California presents stimulating, even provocative data.
Concussions are well-documented as one of the most common injuries in the National Basketball Association. Recent studies have also pointed to an increased risk of lower extremity injury in these athletes after both single and recurrent concussions.
In this latest study, “Concussions Increase Lower Extremity Injury Risk in NBA Athletes,” the researchers wanted to assess the risk of lower extremity injury following return to play after single and multiple concussions in National Basketball Association athletes.
The study enrolled 25 NBA athletes who had experienced multiple concussion between 2001 and 2019. The researchers matched athletes with multiple concussion to athletes with a single concussion and to those athletes with no concussion history by age at first concussion, body mass index, position, and career length.
They also recorded the characteristics of any lower extremity injury that occurred after return to play after their first concussion until retirement or current length of active play.
According to the data collected, the average number of lower extremities injuries resulting in missed time after return to play was greater in the multiple concussion group compared to athletes with no concussion (14.60 ±13.90 vs. 5.36 ±6.67; p < 0.001). The likelihood of a future lower extremity injury as well as suffering more than 5 total lower extremity injuries before retirement were greater in the multiple concussion group compared to single concussion athletes (OR, 4.50; 95% CI, 3.12-5.17; p = 0.004; OR: 3.78, 95% CI: 1.36-10.47; p = 0.01).
Athletes in the single concussion cohort also experienced more lower extremity injuries following return to play than the no concussion cohort (10.02 ±10.10 vs. 5.36 ±6.67; p = 0.008). They also had a greater risk of experiencing a lower extremity injury (OR: 3.56, 95% CI: 2.76-21.6; p = 0.002).
Additionally, both multiple concussion and single concussion athletes had a reduced time to experience a lower extremity injury during their active career (HRSC: 0.22, 95% CI: 0.12-0.4; p < 0.001; HRMC: 0.22, 95% CI: 0.1-0.48; p < 0.001).
The researchers wrote, “NBA athletes with multiple and single concussions were approximately 4 times more likely to sustain a lower extremity injury after return to play than their matched no concussion athletes. These results highlight a propensity of athletes with concussion to experience neuromuscular deficits which could lead to lower extremity injuries. More specific risk stratification and return to play protocol may be of benefit following concussions in professional basketball.”
