Knuckle Pads Workup

Updated: Mar 12, 2019
  • Author: Cheryl J Barnes, MD; Chief Editor: Dirk M Elston, MD  more...
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Laboratory Studies

Laboratory studies are not helpful in establishing the diagnosis of knuckle pads.



A biopsy is indicated if the diagnosis is in doubt.


Histologic Findings

The histology of knuckle pads shows changes in both the epidermis and dermis. Epidermal abnormalities include hyperkeratosis and acanthosis. During the proliferative phase, plumb fibroblasts within loose bands of collagen form an unencapsulated dermal nodule. The fibrotic stage is less cellular, with spindle-shaped fibroblasts and thickened, irregular collagen bundles. [29] In the case of the dorsal nodules of Dupuytren disease, the pathologic findings are similar to those seen in the palmar nodules characteristic of this diathesis. [17]