Pachydermodactyly: a forme fruste of knuckle pads?
Related Experiment Video
Updated: Sep 26, 2026

Automated Joint Space Detection Improves Bone Segmentation Accuracy
Published on: November 28, 2025
Alexander J Chamberlain1, Vanessa A Venning, Fenella Wojnarowska
1Department of Dermatology, The Churchill, Oxford Radcliffe Hospitals, UK. alex_chamberlain@hotmail.com
Abstract:
A 16-year-old boy presented with painless swellings localized to the radial and ulnar aspects of his second through to the fifth fingers on the left hand, with more subtle changes affecting two fingers on the opposite hand. This had developed in the absence of mechanical trauma. Investigations for an arthropathy were negative, while a biopsy showed marked epidermal hyperplasia and an expanded dermis. These features are typical of pachydermodactyly, a benign dermatosis of uncertain aetiology. The interesting feature of this case is the presence of knuckle pads in the father of the patient, which raises the possibility that these two similar entities are related.
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