Abstract
BACKGROUND: Progressive collapsing foot deformity (PCFD) is a painful and function-limiting condition most commonly affecting middle-aged and older adults. Although custom foot orthoses (CFOs) are routinely prescribed as a conservative intervention, evidence from large clinical cohorts remains limited. This study aimed to characterise patients with PCFD seeking orthotic care, examine demographic factors associated with pain improvement, evaluate clinical and self-reported outcomes following CFO use, and explore potential interaction effects of CFOs on clinical improvement across sex. METHODS: A retrospective analysis of clinical records between January 1, 2016 and May 31, 2025 extracted 130,365 appointments across 25 Canadian pedorthic clinics, further extrapolated into 669 PCFD encounters and 12,621 asymptomatic controls. Each assessment included pain ratings, Foot Posture Index (FPI), functional tests, gait analysis, and follow-up surveys on CFOs wear time, comfort, and recovery. RESULTS: Results identified that PCFD was more prevalent in females and older adults. Unilateral PCFD limbs demonstrated significantly higher FPI scores (flatter feet) than contralateral healthy limbs. Both sexes demonstrated significant pain reduction following CFOs use, with females reporting higher pain at baseline and follow-up. Mean pain decreased from 6.52 ± 2.56 at assessment to 3.69 ± 2.52 at follow-up (p < 0.0001). Eighty percent of patients reported symptoms improvement, and 56% wore orthoses for more than 6 hours per day. Comfort was positively associated with both wear time and magnitude of pain reduction. CONCLUSIONS: CFOs were associated with meaningful pain reduction, improved function, and high patient-reported benefit in individuals with PCFD. These findings support CFOs as a cost-effective conservative intervention and provide essential data to inform the design of a future randomised controlled trial evaluating their clinical efficacy.