Complications arising from a misdiagnosed giant lipoma of the hand and palm: a case report

Abstract

IntroductionLipomas are benign tumors which may appear in almost any human organ. Their diagnosis rate in the hand region is not known.Case PresentationWe present the case of a 63-year-old Greek Caucasian woman with a giant lipoma of the hand and palm which was not initially diagnosed. After repeated surgical decompression of the carpal tunnel the patient was referred with persisting symptoms of median and ulnar nerve compression and a prominent mass of her left palm and thenar eminence. Clinical examination, magnetic resonance imaging, nerve conduction study and biopsy, revealed a giant lipoma in the deep palmar space (8.0 × 4.0 × 3.75 cm), which was also infiltrating the carpal tunnel. She had already undergone two operations for carpal tunnel syndrome with no relief of her symptoms and she also ended up with a severed flexor pollicis longus tendon. Definitive treatment was performed by marginal resection of the lipoma and restoration of the flexor pollicis longus with an intercalated graft harvested from the palmaris longus. Thirty months after surgery the patient had a fully functional hand without any neurological deficit.ConclusionNot all lipomas of the wrist and hand are diagnosed. Our report tries to emphasize the hidden danger of lipomas in cases with carpal tunnel symptoms. The need for a high index of suspicion in conjunction with good clinical evaluation and the use of appropriate investigative studies is mandatory in order to avoid unnecessary operations and complications. Marginal excision of these tumors is restorative.

Lipoma in Thenar Region

“…4 Surgical excision is the treatment of choice for thenar intramuscular lipoma. 5,8,9 In most reported cases, surgical excision of the lipoma resulted in full functional recovery. Due to its rarity, the recurrence rate is unclear.…”

Carpal Tunnel Syndrome Caused by Bifid Median Nerve in Association with Anomalous Course of the Flexor Digitorum Superficialis Muscle at the Wrist

“…The most reported nerve affected by lipoma is the radial nerve, which is usually affected with subfascial, parosteal lipomas 7,12,16,25) , followed by the median 5,6,8,10,14,18,22,27) and ulnar nerves 9,21) . Involvement of the nerves in the upper extremity is more common than those in the lower extremity and the reports regarding involvement of the median nerve by a lipoma within carpal tunnel are now increasing 5,6,14,18,22) . Although symptomatic involvement of the median nerve in the proximal forearm by a lipoma has been reported twice 13,27) , to our knowledge, the case presented is the first of compression of the median nerve by a lipoma in the distal forearm just proximal to the wrist.…”

“…However, MRI could provide more information in those situations in which greater number of structures may have been affected by the lesions, such as brachial plexus or popliteal fossa involvement 8) . Not all lipomas of the wrist and hand are preoperatively diagnosed, and their diagnostic rate in the hand region is not known 18) . The risk of neurologic deficit and iatrogenic sever-ing of the flexor pollicis longus tendon has been reported in a patient with giant lipoma of the hand who was not adequately investigated and treated with two carpal tunnel releases 18) .…”

“…Not all lipomas of the wrist and hand are preoperatively diagnosed, and their diagnostic rate in the hand region is not known 18) . The risk of neurologic deficit and iatrogenic sever-ing of the flexor pollicis longus tendon has been reported in a patient with giant lipoma of the hand who was not adequately investigated and treated with two carpal tunnel releases 18) . In the present case, bilateral idiopathic carpal tunnel syndromes were found to be associated with median nerve compression in the left distal forearm just proximal to the carpal tunnel, according to physical examinations, an electrodiagnostic study, and a preoperative MRI scan.…”

“…Among the nonneural sheath-origin tumors, lipomas are a very rare cause of peripheral nerve compression 8) . Therefore, peripheral nerve compression by lipoma is infrequently reported in the medical literature, and most reports are restricted to case reports and small series of patients 3,5,6,[9][10][11]13,14,17,18,20,21,[23][24][25]27) . Lipomas are benign fatty tumors that are common in humans; it is a globose or ovoid mass which is mostly localized in the subcutaneous tissue 15) .…”