This chapter deals with all aspects of the nails in health and disease apart from hereditary nail disorders and fungal infections of the nails which are addressed in Chapters 69 and 32, respectively. Nail biology and growth establishes the basis for an understanding of how the nail may be affected by disease processes and their treatment. The significance of nail signs, which may be an important indicator of systemic diseases, is fully discussed before individual disorders of the nail and perionychium are described. The section on dermatoses affecting the nails includes the main categories of inflammatory and neoplastic diseases seen at other sites in the skin, but as expressed in the nail unit. The diagnostic imaging of the nail and nail surgery sections highlight special considerations required in managing disorders of the nail. Finally, the reader is introduced to cosmetic procedures used on nails and problems which may arise from them.

Keywords nail biology, nail signs, nail diseases, nails and dermatoses, nails in systemic disease, nail trauma, nail tumours, nail surgery, nail imaging, nail cosmetics