COMBINED TRIGGERING AT THE WRIST AND FINGERS AND SEVERE CARPAL TUNNEL SYNDROME CAUSED BY MACRODYSTROPHIA LIPOMATOSA. CASE REPORT AND REVIEW OF LITERATURE

INTRODUCTION

Macrodystrophia lipomatosa (MDL) is a rare form of non-hereditary congenital, developmental anomaly causing localized overgrowth of a digit(s) or extremity consisting of predominately fibroadipose tissue (1). Trigger wrist is a relatively rare entity, which may be caused by a mass originating from a tendon, an anomalous muscle or intracarpal pathologies (2,3). We present a case of triggering at the wrist and carpal tunnel syndrome due to carpal bone enlargement and lipofibromatous hamartoma (LH) of the median nerve in a patient with MDL.

CASE REPORT

A 42-year-old man presented with triggering during active movements of the fingers and intractable pain and numbness in the fingers to our emergency department. His entire right upper extremity was hypertrophic (Fig. 1). His thumb was amputated at the base of metacarpal 4 years ago. The index finger was bigger than the other fingers and the thenar eminence area of the hand looked like a large mass. He presented a history of progressive enlargement, especially of the right thumb and index finger since his early childhood. He was operated 4 times (3 times debulking of palmar mass and one time amputation of the thumb and distal phalanx of the index finger). He could not flex his wrist and index finger. His complains increased in the last two weeks and he could not extend his normal fingers. On physical examination, he could flex actively his finger but he could not extend it. We could extend his fingers passively and the extension was very limited and painful. X-ray image has shown diffuse and disproportional enlargement in the carpal bone (Fig. 2).

During the operation, hypertrophic carpal bone was seen and carpal tunnel was extremely narrowed due to this bony enlargement. We divided flexor carpi radialis (FCR) tendon from its insertion and excised the bony enlargement and excessive palmar soft tissue mass and noticed the disappearance of triggering in the wrist and fingers peroperatively. We released the yellowish lipomatous-like enlarged median nerve, 1.5 to 2 cm in diameter, compressed under the flexor retinaculum and took biopsy from the cutaneous branch of the median nerve. We reconstructed insertion of FCR with a tendon graft harvested from the distal part of the flexor pollicis longus (FPL) tendon (Fig. 3). The operation was completed with skin closure and proper hand dressing and splinting. After the operation, symptoms of triggering in the wrist and fingers and carpal tunnel syndrome disappeared. After 4 weeks of hand immobilization and hand rehabilitation, the patient gained his hand function. The patient was very satisfied both with the aesthetic and functional result of the operation (Fig. 4). Histologically, the biopsy of the cutaneous brunch of the median nerve showed lipofibromatous hamartoma.

DISCUSSION

MDL is a rare developmental anomaly. Megalodactyly, gigantism, macrodactyly and macrodactylia fibrolipomatosis have been used as alternative terms (1). The anomaly is usually unilateral and may affect more than one digit of the hand or foot and rarely the entire extremity. The disorder is generally recognized at birth or in the early years of life. The aetiology of MDL is unknown. MDL is characterized by lipomatous hypertrophy of subcutaneous tissue, muscle and nerves and bone abnormalities (erosion, exostosis, ankylosis of the interphalangeal joints and obliteration of medullar cavity) (1). Compression neuropathies associated with fatty infiltration of the median or ulnar nerves or lipomatous mass in carpal tunnel were presented in the literature (4,5). Jain R et al reported first case of macrodystropia lipomatosa involving an entire upper limb. In this article, they did not provide any information regarding treatment of the patient (6). Gao B reported second case of MDL involving an entire upper limb and they presented the first report of successful limb salvage surgery of the case of a 14 year-old girl and they removed an 18 kg soft tissue mass (the excision of an 18 kg mass) from her right arm (7). Our case is a third case of MDL involving the entire upper limb and first case with triggering at the wrist and severe carpal tunnel syndrome due to carpal bone enlargement caused by MDL.

Treatment of the patient with MDL should be planned according to the type of MDL, rate of progression and the age of the patient. The aim of treatment is to lessen the disproportion in length and circumference between the affected and unaffected digits to preserve sensation of the fingertip, and to maintain motion at the metacarpophalangeal joint. The outcome of the surgical procedures is based upon improving the cosmetic appearance and function of the hand (8). Progressive MDL often requires multiple surgical interventions (such as repeated debulking, partial amputation, decompression of nerve compression) (5,7,8). Our case is a progressive form of MDL. If the symptoms of carpal tunnel recur due to the enlargement of carpal bones or progressive soft tissue enlargement, new surgical interventions may be needed (debulking or decompression of the nerves). We informed our patient about the possible risk of progressive MDL disease.

Trigger wrist was first reported by Eibel 1961 and has been used for cases in which either passive or active movement of the wrist or the fingers caused triggering of the wrist (9). Trigger wrist is an uncommon condition, which may be caused by a mass originating from a flexor or extensor tendon (fibroma, giant-cell tumour of the flexor sheath, gouty tophus, hemangioma, lipoma), an anomalous muscle, rheumatoid nodule, intracarpal pathologies (1,3,10). Suematsu 1985 classified the aetiology of wrist triggering into three types. but this classification involved only flexor tendon pathology and did not include problems of extensor tendon and intracarpal pathologies (3). Our case was an example of intracarpal pathology. Progressive carpal bone enlargement in the wrist caused triggering of the flexor tendons of the fingers in our case. Giannikas reported 3 cases with trigger wrist and suggested that Suematsu’s classification cannot explain all causes of trigger wrist and a new extended and comprehensive trigger wrist classification should be prepared (3).

Triggering in the wrist and carpal tunnel syndrome due to carpal bone enlargement in MDL was not hitherto described in the literature. Hand surgeons should know and inform the patient about nerve compression and functional restrictions due to MDL.

Address for correspondence:

Kamuran Zeynep Sevim M.D.

Şişli Etfal Hastanesi 7. Kat Plastik Cerrahi Kliniği Şişli

Istanbul, Turkey

E-mail:kzeynep.sevim@gmail.com