Abstract
Objective: Transverse arch flattening and plantar hyperkeratosis are major foot problems for RA patients. A foot orthosis is often used for bolstering the transverse arch. However, diagnostic imaging of transverse arch correction by orthosis had not been reported. We investigated the feasibility of ultrasound (US) diagnosis for the evaluation of the transverse arch.
Methods: A transverse US probe was placed on the dorsal side of metatarsophalangeal (MTP) joints. The transverse arch angle is formed by the line connecting the second MTP to the third MTP joints and the line connecting the third to the fourth MTP joints. Randomization was performed employing the computer-generated block method.31outpatients with RA and plantar hyperkeratosis were treated with a metatarsal pad consisting of a metatarsal pad and reorienting bandage for hallux valgus, or a placebo band made of the reorienting bandage for hallux valgus alone for four weeks. The Foot function index (FFI) at the final assessment was compared with that at baseline in both the metatarsal pad and placebo band groups.
Results: In participants wearing metatarsal pad (n＝15), the transverse arch angle was significantly increased (6.5±5.5°). These significant differences were not found in the placebo band group (n＝16), (P＝0.12). The metatarsal pad group demonstrated significantly improved FFI values in comparison with their baseline assessments (P＝0.002). These significant differences were not found in the placebo band group (P＝0.91).
Conclusion: The efficacy of a metatarsal pad was significant in US diagnosis and clinical assessment in patients with plantar hyperkeratosis of RA.
