12 Wrist and Ankle Appearance Changes Linked to Systemic Inflammation

9. Nail and Periungual Changes

The nail apparatus and surrounding periungual tissues serve as sensitive indicators of systemic inflammation, with various changes in nail appearance and periungual structures providing valuable diagnostic clues about underlying inflammatory processes. Inflammatory mediators circulating in the bloodstream can affect nail matrix function, leading to alterations in nail growth, texture, and appearance that may be among the earliest visible signs of systemic inflammation. Common nail changes include the development of longitudinal ridging, where vertical lines appear along the length of the nail, and transverse ridging or Beau's lines, which represent periods of interrupted nail growth corresponding to inflammatory flares. The nail color may also change, with some patients developing a yellowish discoloration or the appearance of splinter hemorrhages, which are thin, dark lines running vertically under the nail that result from capillary damage. Periungual changes are equally significant and may include erythema and swelling of the nail folds, development of periungual telangiectasias (small dilated blood vessels), and the formation of cuticular overgrowth or ragged cuticles. In some inflammatory conditions, patients may develop nail fold capillary changes that can be visualized with magnification, showing dilated, tortuous capillaries and areas of capillary dropout. These changes may be accompanied by tenderness and increased sensitivity around the nail area. The nail changes associated with systemic inflammation often fluctuate with disease activity and may improve with effective anti-inflammatory treatment, making them useful markers for monitoring therapeutic response.