Did you notice a small indentation or ridge develop on your fingernail, followed by a small growth on the top side of your finger (side your fingernail is on)? Maybe, the mass grew and then some jelly-like fluid came out through the thinned skin or from underneath your nailfold? You may have a mucous (ganglion) cyst. Ganglion Cyst/Mucous Cyst.

Picture 1: Area where you may notice cyst develop circled.

There are many growths that may develop in the distal finger, and these should be evaluated by your treating physician. One of the more common masses is a mucous cyst. These cysts often arise from underlying arthritis of the distal interphalangeal joint of the fingers or the interphalangeal joint of the thumb (joints closest to the fingernail). When they grow large enough, they may place pressure on the germinal matrix. The germinal matrix is responsible for producing your nail plate. When a mass such as a mucous cyst places pressure on this matrix: indentations, ridges, or other deformities of the nail plate may occur.

In circumstances where mucous cysts are small and do not cause symptoms of concern to the patient, observation may be recommended by the treating physician. When larger and symptomatic, the treating physician may recommend surgical treatment. Surgery involves excision of the mucous cyst and possible excision of underlying bone spurs (osteophytes). In circumstances where the overlying skin has become significantly attenuated, a rotation flap may be discussed by the treating physician.

Nail deformities may persist despite surgical treatment. The decision regarding nonoperative versus operative treatment is complex and should be discussed with your treating physician. 

Outcomes after surgical treatments vary and risks and benefits should be discussed in detail with your treating physician. Nonoperative treatment also carries risks and benefits which should be discussed with your treating physician.

Disclaimer: Evaluation and treatment of masses involve complex decision-making. There are many different growths that may develop in the hands and fingers. These should be evaluated by your treating physician. This information is not intended to covey, substitute or supplant any medical advice. In order to establish a treating relationship, please schedule and complete your visits with a licensed physician.

Copyright 2/6/2022 Tanay Amin, MD

Do not copy, distribute, or publish this article. Please contact Precision Hand and Orthopedic Surgery PLLC with regards to any inquiries or corrections.