Association between Pes Planus and Spinal Pathologies: a Retrospective Cohort Study

Introduction: Pes planus influences the health of weight-bearing structures such as the knees and hip; the impact of pes planus on spine health, however, has not been well-elucidated. This study aims to evaluate the association between pes planus and the likelihood of developing spinal pathologies.

Methods: TriNetX, a national network of de-identified patient records, was retrospectively queried using ICD-10, CPT, VA, and ATC codes. Pes planus diagnosis was defined with ICD-10 codes Q66.5 or M21.40 between 2003 and 2013. The control cohort included patients without pes planus over the same interval. Propensity-score matching (PSM) based on demographics, comorbidities, risk factors for disc degeneration, and mood disorders was performed. Outcomes involving spinal pathologies were queried over a 10-year period from index event.

Results: After PSM, each cohort consisted of 18,862 patients. Back pain incidence, as defined by a diagnosis of “dorsalgia” (M54.9), was higher in all age-stratified Pes Planus cohorts versus controls, with highest OR in the 40-49 age group (OR 1.55; 95% CI 1.37-1.76). Rates of lumbar and lumbosacral disc degeneration diagnoses were higher in Pes Planus cohort aged 40-49 (OR 1.54; 95% CI 1.12-2.12), 50-59 (OR 1.59; 95% CI 1.22-2.08), 60-69 (OR 1.61; 95% CI 1.20-2.12), and 70+ (OR 1.91; 95% CI 1.22-2.96). The 60-69 age Pes Planus cohort was associated with developing lumbar/lumbosacral spinal stenosis (OR 1.68; 95% CI 1.17-2.42). Furthermore, pes planus patients received more pharmacotherapies including opioids, steroids, and gabapentin.

Conclusion : Patients with pes planus have a significantly greater association with diagnosis of lumbar and lumbosacral pathologies with concomitant increased utilization of pharmacotherapies. The condition of the arch of the foot should be considered when evaluating a patient's present and future spine health.