Glomus tumors are benign hamartomas that arise from the normal glomus apparatus, located in subcutaneous tissue. The normal glomus body is a contractile neuromyoarterial receptor that controls blood pressure and temperature by regulating flow in the cutaneous microvasculature6)
. Glomus bodies are highly concentrated in the tips of digits, especially under the nail. So, the tumors are usually in the subungual area9)
. The glomus tumor being located in the volar pulp of the distal phalanx is very rare.
Many articles about this tumor have noted that the long duration of symptoms before correct diagnosis and treatment is caused by the tumors being small and usually not palpable, and varying in presentation2,6-8)
. Importantly, the diagnosis of the glomus tumor must be made through the history and clinical examination of the patients. One of the distinguishing features of the glomus tumor is the classic triad of symptoms : hypersensitivity to cold, paroxysmal severe pain, and point tenderness in the finger. There are three main clinical diagnostic tests. The first is Love's pin test, in which the head of a pin is pressed gently against the tender lesion to localize the pain. The second is Hildreth's test. After the patient feels severe pain, a tourniquet is applied to the base of the digit and Love's pin test is repeated. For a positive result, the patient should not experience any pain. The last test is a cold sensitivity test that produces increased pain when the finger is exposed to cold. In addition to these clinical tests, ultrasonographic imaging and magnetic resonance imaging (MRI) can be a valuable method of imaging glomus tumors3,6)
The treatment for glomus tumors is surgical total excision. Complete excision is curative and necessary to avoid recurrence. The incidence of recurrence after surgery has been reported in the range of 5-50%2,5,8,9)
. The standard approach is direct transungual excision : the nail plate is removed and the incision is made on the nail bed. It can afford a better exposure for completely subungual lesions5,8)
. An alternate approach is through a lateral incision. The incision allows exposure to the dorsal distal phalanx without violating the nail matrix, so reducing the risk of postoperative nail deformity9)
. However, the lateral approach affords a more narrow view of the tumor bed, with a higher chance of incomplete excision, compared to the transungual approach4)
. In our case, the lateral approach was enough for complete excision because the lesion was located in volar pulp.