Combined effect of underwater ultrasound and custom-made insoles in rheumatoid arthritis: a randomized controlled trial

The study was registered on the Clinical Trials Registry (registration number: NCT06753552). Key Points • A six-week underwater ultrasound intervention resulted in significant improvements in functional status, mobility, balance, and plantar flexor muscle endurance in individuals with rheumatoid arthritis, regardless of treatment group. • The addition of custom-made foot insoles did not lead to superior clinical outcomes but provided distinct biomechanical advantages by significantly modifying Static Plantar Pressure Distribution. • Group-specific differences were primarily observed in plantar pressure parameters, indicating that insoles mainly influence biomechanical load redistribution rather than subjective clinical outcomes. • Underwater ultrasound may serve as a supportive therapeutic modality in rheumatoid arthritis, while the integration of custom-made foot insoles may offer additional biomechanical benefits, particularly in patients with foot involvement.