Glomus Tumor of the Hand
Glomus tumor of the hand is an uncommon cause of distal finger pain. It is the result of tumor formation of the glomus body, which is a neuromyoarterial apparatus whose function is to regulate peripheral blood flow in the digits. Most patients with glomus tumor are women 30 to 52 years of age. The pain is severe in intensity, lancinating, and boring. The tumor frequently involves the nail bed and may invade the distal phalanx. Patients with glomus tumor of the hand exhibit the classic triad of excruciating distal finger pain, cold intolerance, and tenderness to palpation of the affected digit. Multiple glomus tumors are present in approximately 25% of patients diagnosed with this disease. Glomus tumors also can occur in the foot and occasionally in other parts of the body. Glomus tumors may recur despite surgical extirpation.
What are the Symptoms
The diagnosis of glomus tumor of the hand is based primarily on three points in the patient’s clinical history: (1) excruciating pain localized to a distal digit, (2) the ability to trigger the pain by palpating the area (Love test), and (3) marked intolerance to cold. The pain of glomus tumor can be reproduced by placing the affected digit in a glass of ice water.
If glomus tumor is present, the characteristic lancinating, boring pain occurs within 30 to 60 seconds. Placing other unaffected fingers of the same hand in ice water does not trigger the pain in the affected finger. Hildreth test also is useful in the diagnosis of glomus tumor. It is performed by placing a tourniquet proximal to the area of suspected tumor.
As the distal area becomes ischemic, the sharp lancinating pain characteristic of glomus tumor will occur. Nail bed ridging is present in many patients with glomus tumor of the hand, and a small blue or dark red spot at the base of the nail is visible in 10% to 15% of patients with the disease. The patient with glomus tumor of the hand frequently wears a finger protector on the affected digit and guards against hitting the digit on anything to avoid triggering the pain.
How is this diagnosed?
Magnetic resonance imaging (MRI) of the affected digit often reveals the actual glomus tumor and may reveal erosion or a perforating lesion of the phalanx beneath the tumor. The tumor appears as a very high and homogeneous signal on T2-weighted images. Color Doppler imaging will help confirm the diagnosis.
The bony changes associated with glomus tumor of the hand also may appear on plain radiographs if a careful comparison of the corresponding contralateral digit is made. Radionuclide bone scan also may reveal localized bony destruction. The ice water test mentioned earlier helps the clinician strengthen the diagnosis. Based on the patient’s clinical presentation, additional tests, including complete blood cell count, uric acid level, erythrocyte sedimentation rate, and antinuclear antibody testing, may be indicated. Electromyography is indicated if coexistent ulnar or carpal tunnel syndrome is suspected. Surgical exploration of the affected digit and nail bed often is necessary to confirm the diagnosis.
The triad of localized excruciating distal digit pain, tenderness to palpation, and cold intolerance makes the diagnosis apparent to an astute clinician. Glomus tumor of the hand must be distinguished from other causes of localized hand pain, including subungual melanoma and osteoid osteoma. If a history of trauma is present, fracture, osteomyelitis, tenosynovitis, and foreign body synovitis should be considered.
If there is no history of trauma, gout, other crystal monoarthropathies, tumors, and diseases of the nail and nail bed should be considered. Reflex sympathetic dystrophy should be distinguishable from glomus tumor of the hand because the pain of reflex sympathetic dystrophy is less localized and is associated with trophic skin and nail changes and vasomotor and sudomotor abnormalities. Raynaud syndrome usually involves the entire hand, and the ice water test mentioned typically triggers pain if the “unaffected” finger is tested.
The mainstay of treatment of glomus tumor is surgical removal. Medication management is uniformly disappointing.
Injection of the affected digit in the point of maximal tenderness may provide temporary relief of the pain of glomus tumor and blocks the positive ice water test response, further strengthening the diagnosis.
The main complication associated with glomus tumor of the hand involves the problems associated with delayed diagnosis, mainly ongoing destruction of the bone and nail bed. Although usually localized and well encapsulated, rarely, these tumors can exhibit aggressive invasive tendencies, making complete excision of the tumor and careful follow-up mandatory.
The diagnosis of glomus tumor of the hand is usually straightforward if the clinician identifies the unique nature of its clinical presentation.
Glomus tumors are usually solitary tumors, but a rare autosomal dominant condition characterized by multiple glomus tumors affecting more than one body part has been described.
The clinician should remember that glomus tumors have been known to recur. Because of the rare potential for aggressive, invasive behavior, complete excision and careful follow-up are important.