Clinical Outcomes of Anatomical Total Shoulder Arthroplasty in a Young, Active Population
Glenohumeral arthritis in young, active patients poses many treatment challenges, and significant concerns about component loosening and failure limit the available surgical options.
We conducted a study of the clinical outcomes of total shoulder arthroplasty (TSA) for glenohumeral arthritis in a young, high-demand population. We searched the Military Health System Management Analysis and Reporting Tool database to retrospectively review the cases of all US military service members who had undergone anatomical TSA (Current Procedural Terminology code 23472) between 2007 and 2014. Demographic information, occupational parameters, and clinical outcomes were extracted from electronic medical records.
Twenty-four service members (26 shoulders) met the inclusion criteria. The cohort was predominantly male (n = 25). Mean age was 45.8 years (range, 35-54 years). The most common etiology of glenohumeral arthritis was post-instability arthropathy (50.0%). At mean follow-up of 41 months, 9 patients had a total of 12 complications (46.2%), including 6 component failures caused by neurologic injury (2 cases), adhesive capsulitis (2), and venous thrombosis (2). The reoperation rate for all component failures was 23.1% (6 cases, 5 patients). Ten patients (41.7%) remained on active duty at 2 years, and 5 (20.8%) were subsequently deployed. Ultimately, 9 patients (37.5%) underwent medical discharge for persistent shoulder disability.
TSA in young, active patients provides reliable improvements in range of motion and pain. However, roughly one-third of patients in this study were unable to continue high-demand activities by 2 years after surgery. The short-term complication profile (46.2%) and reoperation rate for component failure (23.1%) should be emphasized during preoperative counseling.
Our analysis was limited by the fact that we used a small patient cohort, contributing to underpowered analysis of the potential risk factors predictive of reoperation and medical discharge. Although our minimum follow-up was 12 months, with the exception of 1 patient who was medically separated at 11.6 months because of shoulder disability, we captured 5 patients (19.2%) who underwent medical separation but who would otherwise be excluded. Therefore, this limitation is not major in that, with a longer minimum follow-up, we would be excluding a significant number of patients with such persistent disability after TSA that they would not be able to return to duty at anywhere near their previous level. In this retrospective study, we were additionally limited to analysis of the data in the medical records and could not control for variables such as surgeon technique, implant choice, and experience. Complete radiographic images were not available, limiting analysis of radiographic outcomes. Given the lack of a standardized preoperative imaging protocol, we could not evaluate glenoid version on axial imaging. It is possible that some patients with early aseptic glenoid loosening had posterior subluxation or a Walch B2 glenoid, which has a higher failure rate.48 The strengths of this study include its unique analysis of a homogeneous young, active, high-risk patient cohort within a closed healthcare system. In the military, these patients are subject to intense daily physical and occupational demands. In addition, the clinical and functional outcomes we studied are patient-centered and therefore relevant during preoperative counseling. Further investigations might focus on validated outcome measures and on midterm to long-term TSA outcomes in an active military population vis-à-vis other alternatives for clinical management.
Conclusion
By a mean follow-up of 3.5 years, only a third of the service members had returned to active duty, roughly a third had retired, and more than a third had been medically discharged because of persistent disability attributable to the shoulder. Despite initial improvements in ROM and pain, midterm outcomes were poor. The short-term complication rate (46.2%) and the rate of reoperation for component failure (23.1%) should be emphasized during preoperative counseling.
