Morphological and radiological features of congenital muscular hypertrophy of the upper limb: experience from a tertiary institution.

Congenital muscular hypertrophy is a rare overgrowth disorder in the phosphatidylinositol-3-kinase related spectrum. In the past 3 years, ten patients with 11 limbs involved were treated in our centre. The aim of the study was to describe the clinical and radiological deformities of these patients. We documented the characteristic clinical morphological changes, such as hypertrophy, loss of wrist flexion, thumb hyperabduction, finger deviation and skin crease changes in the palm. Radiologically, the mean first metacarpal radial deviation angle of the affected side measured 55° (range 34 to 67) compared to the normal contralateral side 42° (range 32 to 53). The mean intermetacarpal space ratio was 1.2 (range 1.1 to 1.4) and the mean palm width ratio was 1.2 (range 1.1 to 1.3). In this study, we were able to further characterize the radiological and morphological changes of congenital muscular hypertrophy of upper limbs, which would be helpful for establishing the diagnosis and monitor treatment of this rare condition.Level of evidence: IV.