Forearm flexor injury is associated with medial ulnar collateral ligament injury in throwing athletes

Background Elbow ulnar collateral ligament (UCL) injuries have become increasingly common in throwing athletes. The forearm flexors (FF) have been studied as biomechanical stabilizers for the medial elbow. However, there are no studies investigating the association of concomitant UCL injuries and FF injuries in throwing athletes. Objective To determine if throwing athletes with a complete UCL injury had a greater likelihood of concomitant FF injury than those with a partial UCL injury. Design Descriptive retrospective epidemiological study. Setting Academic, tertiary care medical center. Patients Throwing related UCL injuries in patients aged 12-24 years. Interventions/Methods Electronic medical records and key word searches identified all patients from January 1, 2010 to December 31, 2019. A board certified and fellowship trained musculoskeletal radiologist reviewed all advanced imaging studies. Results Fifty-four patients (46 male, 8 female, mean age 17.1 years, SD 2.3) were included. Fifty-four UCL injuries (21 complete ruptures, 16 proximal partial injuries, 17 distal partial injuries) were confirmed by magnetic resonance imaging (MRI). Twenty-eight FF injuries (22 strains, 6 tears) were diagnosed with MRI and/or MRI-arthrogram. There was a significant association between sustaining a FF injury and UCL reconstruction (UCL-R) (X-2 = [1, N = 54], = 3.97, P = .046) (15/22, 68.2%), as well as FF injury and UCL injury location (X-2 = [1, N = 33], = 3.86, P = .049) (10/17, distal partial UCL injury, 58.8%). Analysis of FF injury and complete UCL tear is not significant (X-2 = [1, N = 54], = 3.02, P = .08) (14/21, 66.7%). Conclusions The data indicate that FF injury is associated with UCL injury in throwing athletes. Future prospective studies should investigate causation versus correlation of FF and UCL injury in throwing athletes. The results of this study have applications to multiple sports medicine areas that include but are not limited to surgical, nonsurgical, prehabilitation, rehabilitation, and sports performance. This study reveals a strongly significant association between FF injury and concomitant UCL injury in throwing athletes.

Automated summary

This study revealed a significant association between forearm flexor injuries and concomitant ulnar collateral ligament injuries in throwing athletes. Future research should investigate the causation versus correlation of forearm flexor and ulnar collateral ligament injuries.