A solitary osteochondroma of the capitate bone: A case report Rajesh Malhotra, J. Maheshwari, and Amit K. Dinda, New Delhi, India
Solitary osteochondromas in the hand are unusual. We recently treated a man in whom this lesion arose from a carpal bone after skeletal maturity and showed persistent growth.
Case report A 30-year-old manual laborer complained of a painless swelling of 8 months' duration on the dorsum of his right wrist. There was no history of injury. Examination showed a 4 X 3 em very hard nodular mass, which was not tender, fixed to the underlying carpal bones. The overlying skin was normal. There was some limitation of wrist extension. A plain x-ray film revealed a bony excrescence related to the distal carpal row (Fig. 1), and a cr scan of the wrist showed it to arise from the capitate (Fig. 2). At operation it was found to be a gray-white, firm tumor attached to the capitate. The tumor had a central bony stalk with a covering of cartilage. Histologic examination confirmed the diagnosis of osteochondroma (Fig. 3).
Discussion Although solitary osteochondromas are common in human beings, fewer than 1% of these tumors occur in the hand and most of these are thought to follow trauma. I, 2 The tumor has been reported in the carpus;' but this is a very uncommon location. Wrist bones, although formed from cartilage, are unusual sites of osteochondroma because they develop from centrifugally expanding centers of ossification. Long bones form in this fashion, but in long bones the osteochondromas arise not from the epiphyses but from the jux-
From the Department of Orthopaedic Surgery, All India Institute of Medical Sciences, New Delhi, India. Received for publication July lO, 1991; accepted in revised form Oct. l4, 1991. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Reprint requests: 1. Maheshwari, Department of Orthopaedic Surgery, All India Institute of Medical Sciences, New Delhi-lIOO29, India. 3/1/34391
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THE JOURNAL OF HAND SURGERY
Fig. 1. X-ray film showing bony growth from distal carpal bones.
taepiphyseal area." This leads to the possible conclusion that some of these lesions are true tumors rather than developmental defects.
REFERENCES 1. Howard LD Jr. Tumors of the hand. In: Boyes J, ed. Bunnell's surgery of the hand. 3rd ed. London: Pitman, 1956. 2. Mason ML. Tumors of the hand. Surg Gynecol Obstet 1937;64: 129-48. 3. Medlar RC, Sprague HH. Osteochondroma of the carpal scaphoid. J HAND SURG 1979 ;4: 150-1. 4. Jaffe HL. Tumors and tumorous conditions of the bones and joints. Philadelphia: Lea & Febiger, 1958.
Vol. 17A, No.6 November 1992
Solitary osteochondroma of capitate bone
Fig. 2. CT scan showing bony growth from capitate.
'.
Fig. 3. Photomicrograph showing large cartilaginous cap with foci of proliferating chondrocytes. (Hematoxylin and eosin stain. Magnification x 120.)
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Solitary osteochondromas in the hand are unusual. We recently treated a man in whom this lesion arose from a carpal bone after skeletal maturity and showed persistent growth.
Case report A 30-year-old manual laborer complained of a painless swelling of 8 months' duration on the dorsum of his right wrist. There was no history of injury. Examination showed a 4 X 3 em very hard nodular mass, which was not tender, fixed to the underlying carpal bones. The overlying skin was normal. There was some limitation of wrist extension. A plain x-ray film revealed a bony excrescence related to the distal carpal row (Fig. 1), and a cr scan of the wrist showed it to arise from the capitate (Fig. 2). At operation it was found to be a gray-white, firm tumor attached to the capitate. The tumor had a central bony stalk with a covering of cartilage. Histologic examination confirmed the diagnosis of osteochondroma (Fig. 3).
Discussion Although solitary osteochondromas are common in human beings, fewer than 1% of these tumors occur in the hand and most of these are thought to follow trauma. I, 2 The tumor has been reported in the carpus;' but this is a very uncommon location. Wrist bones, although formed from cartilage, are unusual sites of osteochondroma because they develop from centrifugally expanding centers of ossification. Long bones form in this fashion, but in long bones the osteochondromas arise not from the epiphyses but from the jux-
From the Department of Orthopaedic Surgery, All India Institute of Medical Sciences, New Delhi, India. Received for publication July lO, 1991; accepted in revised form Oct. l4, 1991. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Reprint requests: 1. Maheshwari, Department of Orthopaedic Surgery, All India Institute of Medical Sciences, New Delhi-lIOO29, India. 3/1/34391
1082
THE JOURNAL OF HAND SURGERY
Fig. 1. X-ray film showing bony growth from distal carpal bones.
taepiphyseal area." This leads to the possible conclusion that some of these lesions are true tumors rather than developmental defects.
REFERENCES 1. Howard LD Jr. Tumors of the hand. In: Boyes J, ed. Bunnell's surgery of the hand. 3rd ed. London: Pitman, 1956. 2. Mason ML. Tumors of the hand. Surg Gynecol Obstet 1937;64: 129-48. 3. Medlar RC, Sprague HH. Osteochondroma of the carpal scaphoid. J HAND SURG 1979 ;4: 150-1. 4. Jaffe HL. Tumors and tumorous conditions of the bones and joints. Philadelphia: Lea & Febiger, 1958.
Vol. 17A, No.6 November 1992
Solitary osteochondroma of capitate bone
Fig. 2. CT scan showing bony growth from capitate.
'.
Fig. 3. Photomicrograph showing large cartilaginous cap with foci of proliferating chondrocytes. (Hematoxylin and eosin stain. Magnification x 120.)
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