Matrix Biopsy of Longitudinal Melanonychia and Longitudinal Erythronychia: A Step-by-Step Approach

Longitudinal melanonychia and longitudinal erythronychia are presentations that may indicate underlying malignancy. Biopsy is commonly required. This manuscript provides an overview to approaching these problems, a guide to surgery including several biopsy techniques, and tips to ensure adequate tissue sampling while minimizing postoperative complications.