Subungual glomus tumor.

Subungual glomus tumors arise from the glomus body of the digits. They are rare and benign and often in a single location. Their diagnosis relies on the typical clinical triad of symptoms and on imaging findings, mainly magnetic resonance imaging with gadolinium injection. Subungual tumors treatment is complete resection, essential for cure. The different surgical techniques aim to: a painless digit with normal range of motion and sensitivity, without nail deformity after tumour resection, and to recurrence prevention. They vary according to tumor location. Classic surgical approaches are: the nail unit sparing ones (para-ungual, lateral subperiosteal, periungual), and the nail unit non-sparing ones (all transungual approaches with nail bed splitting). In this paper, we review the literature for the different approaches describing the advantages and drawbacks of each of them. We also describe the author's preferred subperiosteal "shark mouth" flap containing the nail plate and the nail bed as a single unit. It can be performed whether the tumor is located centrally, peripherally, or under the germinal matrix with very satisfactory outcomes.