Fibromyalgia syndrome is an independent predictor of increased complications, revision, and cost of admission within 180 days of total shoulder arthroplasty

Background

Fibromyalgia syndrome (FMS) frequently afflicts patients undergoing total shoulder arthroplasty (TSA), yet research investigating the effects of FMS on postoperative outcomes following TSA is lacking. The purpose of this study is to determine if patients with FMS are at increased risk for complications, readmission, revision, and mortality following primary elective TSA compared to a matched cohort of patients without FMS.

Methods

The Nationwide Readmissions Database was queried from 2016 to 2020 to identify patients who underwent elective primary TSA. Patients were stratified into two groups based on the presence of preoperative FMS. Patients with FMS were matched 1:1 based on age, sex, and Charlson-Deyo Comorbidity Index using an optimized matching algorithm to patients without FMS to generate an equal sized control group for statistical comparison. 5506 matched pairs of patients with and without FMS were identified and used for statistical analysis. Preoperative demographic and comorbidity data, postoperative outcomes, and economic and hospital metrics were compared between the two groups. Multivariate analysis was conducted to control for the influence of independent risk factors other than FMS on postoperative outcomes.

Results

Patients with FMS were more likely to be active smokers (P < .001) and have chronic kidney disease (P < .001) prior to surgery. Patients with FMS exhibited increased rates of complications, including requiring a transfusion (P = .002), acute respiratory distress syndrome (P < .001), surgical site infection (P < .001), dislocation (P < .001), prosthetic loosening (P < .001), and fracture (P < .001) compared to patients without FMS. Patients with FMS also exhibited higher rates of all-cause complications (P < .001) and revision TSA (P < .001) and decreased rates of readmission (P = .002) within 180 days of surgery. Mean cost of admission was found to be $1639 higher in patients with FMS (P < .001), despite no difference in total hospital length of stay or discharge disposition.

Conclusion

Patients with FMS are more likely to develop medical and surgical complications following primary TSA. Though associated with multiple comorbidities, FMS is an independent predictor of several adverse events. Orthopedic surgeons should be aware of the increased risk of FMS on TSA when determining treatment plans.