Injectable percutaneous polydimethicone in the treatment of pedal keratomas: a single blind randomized trial

Thirty-one subjects who presented with plantar (metatarsal lesions only 21 out of 31 patients completed the study) completed a single blind injection of 350-centistroke polydimethicone or saline over a 6 to 9-month period. The injectable silicone conformed to European Economic Community standards and was accepted by the Medical Devices Agency (UK). The subjects were equally divided between male and female. Two randomly divided groups received silicone (n = 16) and sterile saline (n = 15). Total volumes used were not identical between the groups of subjects (p = .05), although the maximum volume was no greater than 1.5 ml in any subject. The effectiveness of the injection was reviewed using a Harris-Beath ink mat, visual analogue scale, alteration in frequency of treatment, and subjective analysis of reduction in lesions before and after by color photography. Essential histopathology was undertaken on 11 subjects. Granulomatous reactions were only positively identified in one case. Nine matched pairs showed no statistically significant difference between the two treatments (p = .082) using parametric and nonparametric tests. This study found no evidence to show that small quantities of medically prepared liquid silicone caused adverse reactions, although two cases were more sensitive after injection of silicone.