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Dysplasia epiphysealis hemimelica of the proximal tibia showing epiphyseal osteochondroma in an adult
DYSPLASIA EPIPHYSEALIS HEMIMELICA OF THE PROXIMAL TIBIA SHOWING EPIPHYSEAL OSTEOCHONDROMA IN AN ADULT TETSUYA SHINOZAKI, MD, DMSc, TOMOMI OHFUCHI, MD, HIDEOMI WATANABE, MD, DMSc, JUN AOKI, MD, DMSc, TOSHIO FUKUDA, MD, DMSc, AND KENJI TAKAGISHI, MD, DMSc
A 33-year-old woman was referred to our hospital complaining of pain and a tumorous lesion in her left knee joint in the absence of any history of trauma. Radiological examinations demonstrated an osseous mass originating from the epiphysis of the proximal tibia, with a continuous osteoblastic lesion involving the lateral half of the epiphysis. The pathological diagnosis of these lesions was compatible with that of osteochondroma. The clinical and pathological features of this case were considered to be identical with those of dysplasia epiphysealis hemimelica, although this patient was older than patients described in previous reports, and demonstrated no other symptoms such as valgus or varus deformity or limb-length discrepancy. Elsevier Science Inc., 1999 KEY WORDS:
Dysplasia epiphysealis hemimelica; Epiphyseal osteochondroma; Adult; Arthroscopy; Magnetic resonance imaging
INTRODUCTION Epiphyseal osteochondroma due to trauma has occasionally been reported (1, 2). Exostotic masses may also be associated with dysplasia epiphysealis hemiFrom the Department of Orthopedic Surgery, Gunma University Faculty of Medicine (T.S., T.O. H.W., K.T.), Department of Diagnostic Radiology, Gunma University Faculty of Medicine (J.A.), and Department of Laboratory Sciences & Pathology, Gunma University School of Health Sciences (T.F.) Address reprint requests to: T. Shinozaki, MD, DMSc, Department of Orthopedic Surgery, Gunma University Faculty of Medicine, 3-39-22 Showa Maebashi, Gunma, 371-8511 Japan. Received February 23, 1999; accepted April 29, 1999. CLINICAL IMAGING 1999;23:168–171 Elsevier Science Inc., 1999. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
melica (DEH) (3, 4). DEH is an uncommon skeletal developmental disorder affecting the epiphysis in young children. It usually affects the lower limbs, predominantly the knee and ankle. A valgus or varus deformity or limb-length discrepancy may be the presenting symptom (4, 5). However, to the best of our knowledge, there is no report of epiphyseal osteochondroma developing from DEH in an adult with no other symptoms. Reported here may be a mild form of DEH affecting the proximal tibia in an adult associated with epiphyseal osteochondroma alone.
CASE REPORT A 33-year-old woman was referred to our hospital in December 1996, complaining of pain in her left knee joint, and a tumorous lesion in the absence of any history of trauma. She had initially noted the tumorous lesion in 1993. She felt a pain as this lesion associated with increased body weight after she became pregnant in May 1995. The pain became worse after she was delivered of a baby. She felt rest pain and limped when she was referred to our hospital. On physical examination, a tumorous lesion measuring about 2 centimeters in diameter was palpable around the lateral knee joint space. The range of motion of her left knee joint was slightly limited due to the local pain. Laboratory data were uniformly within normal limits. Plain roentgenography showed a well-circumscribed osseous mass at the lateral border of the knee joint and an osteoblastic lesion within the proximal epiphysis of the tibia (Figure 1). However, there were no abnormalities such as joint deformity, valgus or varus deformity, or limb-length discrepancy. Both plain and computed tomography showed the 0899-7071/99/$–see front matter PII S0899-7071(99)00124-2
MAY/JUNE 1999
EPIPHYSEAL OSTEOCHONDROMA FROM DEH IN AN ADULT
FIGURE 1. Plain roentgenography showing well-circumscribed exostotic mass at the lateral border of the knee joint space and an osteoblastic lesion at the proximal epiphysis of the tibia.
continuity of these two lesions (Figure 2A and B). Arteriography demonstrated moderate neovascularity at the exostotic mass (Figure 3). On T1-weighted magnetic resonance (MR) images, both the exostotic mass and osteoblastic lesion of the tibial epiphysis
169
showed low signal intensity (Figure 4A). On T2weighted MR images, these lesions showed an intermediate signal intensity (Figure 4B). 99mTc-DMSA scintigraphy showed increased uptake at the lateral knee joint space. An operation was performed in January 1997. Arthroscopy revealed no abnormal finding in her knee joint capsule. The tumor, which originated from the tibial osteoblastic lesion extended beneath the iliotibial tract and was adhesive to the lateral joint capsule, was resected. The pathological diagnosis was osteochondroma, showing a cartilagineous cap and a zone of chondro-osseous transformation (Figure 5A). Exploratory surgery of the tibial osteoblastic lesion was also performed at that time. The pathology showed osseous tissue with a partial cartilagineous cap (Figure 5B). After the operation, she experienced relief of the local pain, and regained full range of motion of the knee joint.
DISCUSSION Osteochondroma is one of the most common benign bone tumors. This lesion is related to the herniation of epiphyseal plate cartilage through a periosteal cuff
FIGURE 2. Plain (A and B) and computed (C) tomography showing the continuity of the lesions.
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FIGURE 3. Digital subtraction angiography demonstrating neovascularity at the exostotic mass.
defect. Herniated tissue can grow unrestrainedly and aberrantly in the direction of least resistance, resulting in the gradual evolution of the osteochondroma with bone growth. For these reasons, osteochondromas are theoretically located in the metaphysis or diaphysis. None are epiphyseally centered (6). Dysplasia epiphysealis hemimelica (DEH) is characterized by an osteocartilaginous outgrowth affecting half of the epiphysis (4, 5). Some epiphyseal osteochondromas are categorized in this disorder (3). Histologically, the epiphyseal lesion is indistinguishable from metaphyseal osteochondromas (5). Our case showed an epiphyseal exostotic mass of the proximal tibia with a continuous osteoblastic lesion involving the lateral half of the epiphysis without any trauma in the past history. The pathological diagnosis of these lesions was compatible with that of osteochondroma. Considering these facts, the clinical and pathological features of this case were identical with DEH, although this case was older than those described in previous reports and demonstrated no other symptoms such as valgus or varus deformity or limb-length discrepancy (3–5). We should keep in mind a mild form of DEH when we see an epiphyseal osteochondroma in the absence of any trauma in the past history.
We thank Mr. Kiichi Osawa for his technical assistance in making the figures.
FIGURE 4. T1- (A; TR 5 450 msec, TE 5 18 msec) and T2weighted (B; TR 5 3000 msec, TE 5 80 msec) MR images. It shows low signal intensity on T1-weighted images and intermediate signal intensity on T2-weighted images.
REFERENCES 1. Learmonth DJA, Raymakers R. Osteochondroma of the femoral neck secondary to a slipped upper femoral epiphysis. Arch Orthop Trauma Surg 1993;112:106–107. 2. Light TR, Ogden JA. Complex dislocation of the index metacarpophalangeal joint in children. J Pediatr Orthop 1988;8:300–305. 3. Edeiken J. Dysplasia epiphysealis hemimelica. In Roentgen Diagnosis of Disease of Bone (third ed). Baltimore: Williams & Wilkins, 1981;1286–1287. 4. Keret D, Spatz DK, Caro PA Mason DE. Dysplasia epiphysealis
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hemimelica: Diagnosis and treatment. J Pediatr Orthop 1992; 12:365–372. 5. Rao SB, Roy DR. Dysplasia epiphysealis hemimelica. Upper limb involvement with associated osteochondroma. Clin Orthop 1994;307:103–109. 6. Mirra JM. Benign cartilaginous exostoses; Osteochondroma and osteochondromatosis. In Mirra JM, Picci P, Gold RH (eds): Bone Tumors; Clinical, Radiologic, and Pathologic Correlations. Philadelphia: Lea & Febiger, 1989;1626–1659.
FIGURE 5. The pathological findings of the osseous mass (A, HE x 35) and osteoblastic lesion (B, HE x 88). Both areas show a cartilagineous cap and a zone of chondro-osseous transformation.
A 33-year-old woman was referred to our hospital complaining of pain and a tumorous lesion in her left knee joint in the absence of any history of trauma. Radiological examinations demonstrated an osseous mass originating from the epiphysis of the proximal tibia, with a continuous osteoblastic lesion involving the lateral half of the epiphysis. The pathological diagnosis of these lesions was compatible with that of osteochondroma. The clinical and pathological features of this case were considered to be identical with those of dysplasia epiphysealis hemimelica, although this patient was older than patients described in previous reports, and demonstrated no other symptoms such as valgus or varus deformity or limb-length discrepancy. Elsevier Science Inc., 1999 KEY WORDS:
Dysplasia epiphysealis hemimelica; Epiphyseal osteochondroma; Adult; Arthroscopy; Magnetic resonance imaging
INTRODUCTION Epiphyseal osteochondroma due to trauma has occasionally been reported (1, 2). Exostotic masses may also be associated with dysplasia epiphysealis hemiFrom the Department of Orthopedic Surgery, Gunma University Faculty of Medicine (T.S., T.O. H.W., K.T.), Department of Diagnostic Radiology, Gunma University Faculty of Medicine (J.A.), and Department of Laboratory Sciences & Pathology, Gunma University School of Health Sciences (T.F.) Address reprint requests to: T. Shinozaki, MD, DMSc, Department of Orthopedic Surgery, Gunma University Faculty of Medicine, 3-39-22 Showa Maebashi, Gunma, 371-8511 Japan. Received February 23, 1999; accepted April 29, 1999. CLINICAL IMAGING 1999;23:168–171 Elsevier Science Inc., 1999. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
melica (DEH) (3, 4). DEH is an uncommon skeletal developmental disorder affecting the epiphysis in young children. It usually affects the lower limbs, predominantly the knee and ankle. A valgus or varus deformity or limb-length discrepancy may be the presenting symptom (4, 5). However, to the best of our knowledge, there is no report of epiphyseal osteochondroma developing from DEH in an adult with no other symptoms. Reported here may be a mild form of DEH affecting the proximal tibia in an adult associated with epiphyseal osteochondroma alone.
CASE REPORT A 33-year-old woman was referred to our hospital in December 1996, complaining of pain in her left knee joint, and a tumorous lesion in the absence of any history of trauma. She had initially noted the tumorous lesion in 1993. She felt a pain as this lesion associated with increased body weight after she became pregnant in May 1995. The pain became worse after she was delivered of a baby. She felt rest pain and limped when she was referred to our hospital. On physical examination, a tumorous lesion measuring about 2 centimeters in diameter was palpable around the lateral knee joint space. The range of motion of her left knee joint was slightly limited due to the local pain. Laboratory data were uniformly within normal limits. Plain roentgenography showed a well-circumscribed osseous mass at the lateral border of the knee joint and an osteoblastic lesion within the proximal epiphysis of the tibia (Figure 1). However, there were no abnormalities such as joint deformity, valgus or varus deformity, or limb-length discrepancy. Both plain and computed tomography showed the 0899-7071/99/$–see front matter PII S0899-7071(99)00124-2
MAY/JUNE 1999
EPIPHYSEAL OSTEOCHONDROMA FROM DEH IN AN ADULT
FIGURE 1. Plain roentgenography showing well-circumscribed exostotic mass at the lateral border of the knee joint space and an osteoblastic lesion at the proximal epiphysis of the tibia.
continuity of these two lesions (Figure 2A and B). Arteriography demonstrated moderate neovascularity at the exostotic mass (Figure 3). On T1-weighted magnetic resonance (MR) images, both the exostotic mass and osteoblastic lesion of the tibial epiphysis
169
showed low signal intensity (Figure 4A). On T2weighted MR images, these lesions showed an intermediate signal intensity (Figure 4B). 99mTc-DMSA scintigraphy showed increased uptake at the lateral knee joint space. An operation was performed in January 1997. Arthroscopy revealed no abnormal finding in her knee joint capsule. The tumor, which originated from the tibial osteoblastic lesion extended beneath the iliotibial tract and was adhesive to the lateral joint capsule, was resected. The pathological diagnosis was osteochondroma, showing a cartilagineous cap and a zone of chondro-osseous transformation (Figure 5A). Exploratory surgery of the tibial osteoblastic lesion was also performed at that time. The pathology showed osseous tissue with a partial cartilagineous cap (Figure 5B). After the operation, she experienced relief of the local pain, and regained full range of motion of the knee joint.
DISCUSSION Osteochondroma is one of the most common benign bone tumors. This lesion is related to the herniation of epiphyseal plate cartilage through a periosteal cuff
FIGURE 2. Plain (A and B) and computed (C) tomography showing the continuity of the lesions.
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CLINICAL IMAGING VOL. 23, NO. 3
FIGURE 3. Digital subtraction angiography demonstrating neovascularity at the exostotic mass.
defect. Herniated tissue can grow unrestrainedly and aberrantly in the direction of least resistance, resulting in the gradual evolution of the osteochondroma with bone growth. For these reasons, osteochondromas are theoretically located in the metaphysis or diaphysis. None are epiphyseally centered (6). Dysplasia epiphysealis hemimelica (DEH) is characterized by an osteocartilaginous outgrowth affecting half of the epiphysis (4, 5). Some epiphyseal osteochondromas are categorized in this disorder (3). Histologically, the epiphyseal lesion is indistinguishable from metaphyseal osteochondromas (5). Our case showed an epiphyseal exostotic mass of the proximal tibia with a continuous osteoblastic lesion involving the lateral half of the epiphysis without any trauma in the past history. The pathological diagnosis of these lesions was compatible with that of osteochondroma. Considering these facts, the clinical and pathological features of this case were identical with DEH, although this case was older than those described in previous reports and demonstrated no other symptoms such as valgus or varus deformity or limb-length discrepancy (3–5). We should keep in mind a mild form of DEH when we see an epiphyseal osteochondroma in the absence of any trauma in the past history.
We thank Mr. Kiichi Osawa for his technical assistance in making the figures.
FIGURE 4. T1- (A; TR 5 450 msec, TE 5 18 msec) and T2weighted (B; TR 5 3000 msec, TE 5 80 msec) MR images. It shows low signal intensity on T1-weighted images and intermediate signal intensity on T2-weighted images.
REFERENCES 1. Learmonth DJA, Raymakers R. Osteochondroma of the femoral neck secondary to a slipped upper femoral epiphysis. Arch Orthop Trauma Surg 1993;112:106–107. 2. Light TR, Ogden JA. Complex dislocation of the index metacarpophalangeal joint in children. J Pediatr Orthop 1988;8:300–305. 3. Edeiken J. Dysplasia epiphysealis hemimelica. In Roentgen Diagnosis of Disease of Bone (third ed). Baltimore: Williams & Wilkins, 1981;1286–1287. 4. Keret D, Spatz DK, Caro PA Mason DE. Dysplasia epiphysealis
MAY/JUNE 1999
EPIPHYSEAL OSTEOCHONDROMA FROM DEH IN AN ADULT
171
hemimelica: Diagnosis and treatment. J Pediatr Orthop 1992; 12:365–372. 5. Rao SB, Roy DR. Dysplasia epiphysealis hemimelica. Upper limb involvement with associated osteochondroma. Clin Orthop 1994;307:103–109. 6. Mirra JM. Benign cartilaginous exostoses; Osteochondroma and osteochondromatosis. In Mirra JM, Picci P, Gold RH (eds): Bone Tumors; Clinical, Radiologic, and Pathologic Correlations. Philadelphia: Lea & Febiger, 1989;1626–1659.
FIGURE 5. The pathological findings of the osseous mass (A, HE x 35) and osteoblastic lesion (B, HE x 88). Both areas show a cartilagineous cap and a zone of chondro-osseous transformation.