Minimalist Footwear and Knee Joint Loading During Walking in Healthy Adults: A Systematic Review of Evidence for Osteoarthritis Prevention

Abstract

Background/Objectives: Minimalist footwear has been proposed as a passive means of reducing knee loading, but its effects during walking in healthy adults, the population relevant to primary prevention of knee osteoarthritis (KOA), have not previously been synthesized. Methods: Following PRISMA 2020 (PROSPERO CRD420261396693), four databases and ClinicalTrials.gov were searched to September 2026 without date restriction. Primary outcomes were peak knee adduction moment (KAM), KAM impulse, peak knee flexion moment (KFM), and patellofemoral contact force; secondary outcomes were vertical loading rate, stride length, cadence, foot strike angle, and foot progression angle as a registered post hoc amendment. Risk of bias was assessed in duplicate with the Cochrane RoB 2 tool for crossover trials; synthesis was narrative; certainty was rated with GRADE. Results: Six publications met the criteria, but they derive from only four independent cohorts and 100 unique participants: three of the six report the same cohort of 40, a shared structure disclosed in none of them. Two of the four primary outcomes were reported by a single study in one cohort of 16, which found no difference between minimalist and conventional footwear in either peak KAM or peak KFM; KAM impulse and patellofemoral contact force were not reported by any study. Vertical loading rate, spatiotemporal parameters, and foot progression angle were discordant or non-comparable between cohorts. The meta-analysis was precluded by overlapping samples, absent discrete data and non-comparable outcome definitions; certainty was very low for every outcome. Conclusions: The evidence is smaller and less independent than its publication count suggests, and no recommendation for or against minimalist footwear in KOA prevention is currently supportable. Whether these loading markers, studied mainly in relation to progression in established osteoarthritis rather than incident disease in healthy joints, are appropriate prevention targets also remains unclear.