The natural history of paediatric trigger thumbs. A prospective cohort study.

The aim of this study was to report the natural history of paediatric trigger thumbs, determining the rate and factors predictive of spontaneous resolution. A total of 62 patients presenting with 79 thumbs locked in flexion were observed for a mean of 4.2 years. The median age at presentation was 20.5 months. The spontaneous resolution rate was 37% at 5 years and 50% at 8 years of follow-up. Of the thumbs, 27% had undergone surgery at 5 years and 48% at 8 years. Thumbs that spontaneously resolved did so at a mean of 3.4 years. Thumbs presenting with an interphalangeal joint angle of less than 30° were likely to resolve spontaneously, with a sensitivity of 0.50 and specificity of 0.82. It is reasonable to offer observation alone for 4 to 5 years as the first line of management for paediatric trigger thumb.Level of evidence: III.