Risk Factors for Glenohumeral Arthropathy in Collegiate Football Athletes with Shoulder Instability

Abstract

Dislocation arthropathy is a well-documented complication of shoulder instability. The risk factors for the development of this problem are not clear. We performed a radiographic review of the affected shoulder in athletes participating at the NFL combine with a history of anterior glenohumeral instability in an effort to determine whether delayed stabilization lead to higher grades of shoulder arthropathy. We secondarily were interested in assessing the risk factors that correlated with the development of glenohumeral arthrosis. Using available records from athletic trainers and personal interview, athletes participating in the NFL combine were assessed for a history of anterior glenohumeral instability. The number of instability events was recorded as a combination of dislocations and subluxations. Current age, age at time of injury, age at time of surgery, and player position were recorded. All athletes with a history of shoulder instability underwent radiographic testing including multiplane radiographs, MRI and CT scan. De-personalized radiographs of the affected extremity were reviewed by 2 independent physicians and graded using the Samilson and Prieto classification for dislocation arthropathy. Multi-variate analysis was performed to assess variables that predicted severity of glenohumeral arthritis including: age at initial injury, time from injury to surgical intervention, surgical vs nonsurgical treatment, and player position (offense vs defense). 334 athletes underwent a comprehensive orthopedic evaluation during a recent NFL Scouting Combine. 11.4% of players (38 athletes) reported a history of anterior glenohumeral instability with three of the 38 athletes reporting bilateral involvement over their playing career for a total of 41 shoulders. Players surveyed were on average 22.3 years old and 39.3 months from injury. Average age at the time of the initial instability event was 19.2 years. Within this cohort, the average number of instability episodes was 2.1 at the time of evaluation. Of the 41 shoulders, 78 percent of radiographs demonstrated at least Grade 1 glenohumeral arthrosis. Among the athletes that underwent surgical stabilization, those with longer delays between the onset of instability and the date of surgery had worse radiographic arthropathy (p=0.04). When comparing those athletes who underwent surgery to those who were treated non-surgically, those who had undergone surgical stabilization were more likely to have worse arthropathy than the non-surgically treated shoulders (p=0.02). Radiographs revealed a significantly higher grade of arthrosis amongst defensive players as compared to offensive players (1.37 vs 0.79, p=0.004). High-level collegiate football athletes with a history of anterior glenohumeral instability frequently develop radiographic evidence of glenohumeral arthrosis within a few years of injury. Longer time between initial injury and surgical stabilization was associated with more severe arthropathy on radiographic evaluation. Defensive players demonstrate a higher grade of arthrosis as compared to offensive players.