Effect of a thin customized insole on pain and walking ability in rheumatoid arthritis: A randomized study

The aim of the study was to investigate the immediate effects of a thin, easily customizable insole on pain and walking ability in patients with rheumatoid arthritis (RA) who have forefoot pain, and to determine whether the insoles were in use 1 year afterwards.

An experimental, assessor-blinded design was applied to compare the immediate effects when walking with or without insoles in random order. After 1 year, a structured telephone interview was conducted.

Twenty-one subjects with RA and foot pain in at least one forefoot when walking and in response to the Gänslen test were recruited consecutively from the outpatient clinic and the inpatient ward at a hospital for people with rheumatic disease.

Each subject was given a 4-mm thin individually customized insole of a malleable plastic material (CI-Core®) with synthetic textile material on the upper side.

The 6-min walk test (6MWT) was used to assess the ability to walk, and a 10-cm visual analogue scale to measure the intensity of foot pain induced by walking with and without the insole. A standardized questionnaire with five items was used to determine the use of, and degree of satisfaction with, insoles after 1 year.

The median (interquartile range) foot pain intensity was 19 (15) with and 36 (27) without insoles (p < 0.001; effect size = 0.6). No statistically significant differences in 6MWT were found between the presence or absence of insoles (p = 0.07). After 1 year, 90% of the participants were still using the insoles.

The use of thin, easily customizable insoles resulted in immediate clinically relevant relief in walking-induced forefoot pain. Most of the patients were still using the insoles after 1 year.