Bumps on your hand can be caused by a number of conditions including soft tissue masses or solid masses caused by cell tumors. Soft tissue masses can develop in various locations in the hand. In the vast majority of cases, these masses are benign tumors. Here's an overview of some of the most common ones.
The most common soft tissue mass of the hand is the ganglion cyst. This is a cyst, which is caused when the fluid inside of a joint herniates through a weak spot in the joint lining and causes a bulge underneath the skin. This results in a balloon-like structure that is attached to the joint lining by a stalk. These cysts may appear suddenly and often fluctuate in size as the fluid builds up within the cyst and then intermittently returns to the joint. While ganglion cysts can arise from any joint in the hand, the most common locations are the dorsal wrist (“back of the hand”), the volar wrist (“palm side of the hand”), and the flexor retinaculum (the palm side of the finger). Another common site of ganglion cysts is at the last joint in the finger, just below the fingernail. A cyst in this location is called a “mucous cyst” and is caused by degenerative arthritis at the fingertip joint.
Diagnosis of ganglion cysts is based on a physical exam. Many of them “trans illuminate”, or light up, when a small flashlight is shined through them. X-rays are usually normal, but may show evidence of arthritis. An MRI is rarely needed. Unless the cyst is causing thinning over the overlying skin, it is generally safe to observe ganglion cysts. Using a needle to draw out the fluid from a dorsal ganglion cyst will result in a recurrence of the mass about 50% of the time. This is not recommended in volar (palm-side) masses, as the nerves and arteries may be next to the cyst. Surgical excision of the mass will resolve the problem 95% of the time.
The most common solid mass of the hand is the giant cell tumor of the tendon sheath. This is a firm, nodular mass that often arises anywhere in the hand, usually near a joint or a ligament. They are usually not painful to touch. If attached to a tendon, it will move back and forth with finger motion. X-rays will appear normal, and MRI or ultrasound can be helpful if there is a question about the diagnosis. These masses are benign, but can grow quite large. Treatment requires complete surgical removal of the lesion. The tumor often extends deep into the joint and is not completely excised. The rate of recurrence ranges from 5% to 50%, with incomplete excision playing a major factor.
Other hand lesions include certain (benign) tumors of the lining of the nerve (“Schwannoma”) as well as a condition called “Dupuytren’s Disease” in which the fascia of the palm becomes fibrotic and forms lumps and tight bands under the skin. The proper diagnosis and treatment of these lesions require the specialized training of a hand surgeon, as critical structures in the hand such as nerves and tendons are often involved.
Bumps on your hand caused by soft tissue masses or cell tumors can grow to a large size, which interferes with proper function of your hand. For these reasons, it is important to consult with a surgeon trained specifically in disorders of the hand. An experienced hand surgeon can help you to determine the type of mass, what caused it, and how best to remove it in order to return to normal hand function as soon as possible. At Advanced Hand Surgery, our skilled surgeons, registered nurses and medical office staff treat a full range of hand conditions, including ganglion cysts and tumors. Our office is located in Danbury, Connecticut.