Daniel I. Rhon, DSc; Tanja C. Roy, PhD; Robert C. Oh, MD, MPH, FAAFP; Jodi L. Young, DPT
Corresponding Author: Daniel I. Rhon, DSc; Brooke Army Medical Center. Email: daniel.i.rhon.ctr@mail.mil
Section: Original Research
Publication: 3/18/2021
Background: Mental health disorders are associated with persistent knee pain, but the association between these two conditions has had little investigation in the Military. The purpose of this study was to identify rates of mental health disorders in patients with patellofemoral pain, determine differences by sex, and determine if mental health co-presence influences outcomes. Methods: Using the Military Health System Data Repository (MDR) eligible patients with a new patellofemoral pain diagnosis (data from January 2009-December 2013) were categorized according to sex and presence of mental health disorders. Outcomes included odds of mental health disorder before and after initial patellofemoral pain diagnosis based on sex, and knee-related healthcare utilization (costs, visits, recurrence) between patients with and without mental health disorders. Results: In 81,832 individuals with patellofemoral pain (71.1% men; mean age 33; 91.5% active-duty), co-presence of any mental health disorders was common (18% men; 28% women). Women more likely had depression and anxiety; men more likely had PTSD and substance abuse disorders. Concurrent mental health disorders after initial patellofemoral pain diagnosis resulted in higher medical costs (mean difference $200-$456) and visits (mean 1-2.2 extra visits), and greater odds of having a recurrence (OR 1.24; 95CI 1.20, 1.28; p<0.001), compared to patients without a mental health diagnosis. Conclusion: Mental health disorders are common in military service members seeking care for patellofemoral pain. Differences in prevalence vary by sex, and the presence of mental health disorders adversely affected long-term healthcare outcomes. These are key considerations for clinicians seeing patients with patellofemoral pain in this setting.