To compare forefoot pain, pressure and function before and after normal and sham callus treatment in rheumatoid arthritis (RA).
Thirty-eight RA patients were randomly assigned to normal (NCT group) or sham (SCT) scalpel debridement. The sham procedure comprised blunt-edged scalpel paring of the callus which delivered a physical stimulus but left the hyperkeratotic tissue intact, the procedure being partially obscured from the patient. Forefoot pain was assessed using a 100 mm visual analogue scale (VAS), pressure using a high-resolution foot pressure scanner and function using the spatial-temporal gait parameters measured on an instrumented walkway. Radiographic scores of joint erosion were obtained for metatarsophalangeal (MTP) joints with and without overlying callosities. The trial consisted of a randomized sham-controlled phase evaluating the immediate same-day treatment effect and an unblinded 4-week follow-up phase.
During the sham-controlled phase, forefoot pain improved in both groups by only 3 points on a VAS and no statistically significant between-group difference was found (P = 0.48). When data were pooled during the unblinded phase, the improvement in forefoot pain reached a peak after 2 days and gradually lessened over the next 28 days. Following debridement, peak pressures at the callus sites decreased in the NCT group and increased in the SCT group, but there was no statistically significant between-group difference (P = 0.16). The area of and duration of contact of the callus site on the ground remained unchanged following treatment in both groups. Following debridement, walking speed was increased, the stride-length was longer and the double-support time shorter in both groups; however, between-group differences did not reach levels of statistical significance. MTP joints with overlying callus were significantly more eroded than those without (P = 0.02).
Treatment of painful plantar callosities in RA using scalpel debridement lessened forefoot pain but the effect was no greater than sham treatment. Localized pressure or gait function was not significantly improved following treatment.