Clinical Neurology and Neurosurgery ELSEVIER
Clinical Neurology and Neurosurgery 98 (1996) 186-188
Myelopathy due to hereditary multiple exostoses: CT and MR studies Hayati Atabay*, Yusuf Kuyucu, Okan Korkmaz, A. Celal iplikcio~lu Department of Neurosurgery, Tepecik Social Security Hospital, Ali Cetinkaya Bulvart, Doktorlar Sitesi 68/22, Alsancak, izmir, Turkey Received 19 July 1995; revised 8 January 1996; accepted 8 January 1996
Abstract Substantiated myelopathy in hereditary multiple exostoses is very rare. A few cases have been reported previously. We report a case of a 17-year-oldboy with two exostoses in the cervical spine, in one of which caused a high cervical cord compression.
Keywords: Exostosis; Myelopathy; Osteochondroma; Magnetic resonance
1. Introduction Hereditary multiple exostoses (HME) is an inherited autosomal disorder characterized by the multipl osteochondromas arising mainly from the metaphysis of long and flat bones [1-5]. This disease occasionally involves the spine and rarely cause spinal cord compression [3,6,7,8]. In this report, we present a case of HME with high cervical spinal cord compression. To our knowledge, only 11 cases of high cervical spinal cord compression due to HME have been reported previously.
2. Case report
nation disclosed a moderate spastic quadriparesis, bilateral hyperactive deep tendon reflexes, ankle clonus and Babinski reflexes. Hypoesthesia below C5 was also detected. Plain X-ray films of the upper cervical spine were unremarkable. CT scan showed a bony protrusion into the spinal canal, arising from right C2 lamina (Fig. 2). Another exostosis protruding dorsally from the posterior arch of C4 vertebra was also detected (Fig. 3). Magnetic resonance imaging (MRI) revealed the extreme cord compression at the level of C2 vertebrae by the exostoses (Fig. 4). In the operation, C2-3 laminectomies and the removal of exostosis arising from C4 lamina were performed. Marked dural and spinal cord compression at the level of C2 was relieved (Fig. 5). Postoperative period was uneventful. The patient was discharged on the 11th postoperative day. Two months after the operation, the patient was symptom-free and neurologically intact. The histopathological examination resulted in the diagnosis of benign osteochondroma.
A 17-year-old boy was admitted to our hospital with a complaints of weakness in all extremities, neck pain and urinary dysfunction for 2 months. He had been operated on for multiple osteochondromas on his left leg. His father and one of his brothers also had been operated on for multiple exostoses and the diagnosis of HME had been made as a result of family history. On physical examination, he had palpable exostoses over the bones of his legs and arms (Fig. 1). Neurological exami-
HME were first described by Boyer in 1814 . Heredity is manifested in nearly 2/3 of all cases. In the remainder of the patients, is condition arises spontaneously.
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H, A tabay et al. I Clinical Neurology and Neur osurgery 98 (1996) 186-188
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Fig. 1. Radiograph demonstrating multiple exostoses arisen from the metaphyses of leg bones (arrows).
Fig. 2. CT scan of the cervical spine with metrizimide showing the exostosis protrusion into the spinal canal, arising from right C2 lamina and significantly compromising the spinal cord.
Fig. 3. CT scan showing an other exostosis growing from the outer layer of the C4 posterior arch.
Fig. 4. Cervical Tl-weighted and high signal on proton density MR images showing extreme cord compression at the dens level by the exostoses.
There is evident predilection for the male sex (2/1) in hereditary cases [2,10,11]. The exostoses and bone deformities become appearent during childhood and adolescence. New exostosis rarely occurs after growth is completed [12,13]. Clinical findings are usually skeletal deformities due to shortening of bones, exostoses and scoliosis. Exostoses may compress nerves, tendons and vessels and cause pain, limitation of motion, urinary or bowel dysfunction and neurological deficits [2,13,14]. Malignant degeneration to a chondrosarcoma may occur in up to 20% of patients with HME [2,10,14]. Spinal involvement is rare and seen in 7% of the cases [4,14,15]. However, spinal cord compression due to HME is more rare, because most of the cases exostoses grow from the external part of the laminae [12,15]. They usually affect the cervical and upper thoracic region. Exostoses growing in to the spinal canal cause compression of the roots and spinal cord. High cervical spinal cord compression associated with HME are extremely
Fig. 5. Postoperative CT scan showing relived of significant dural and spinal cord compression at the level of C2.
H. Atabay et al./Clinical Neurology" and Neurosurgery 98 (1996) 186-188
rare a n d o n l y 11 such cases have been r e p o r t e d previously. I n these cases, s y m p t o m s have been p r e s e n t for u p to 9 years b e f o r e diagnosis. H o w e v e r , acute cervical m y e l o p a t h y a n d s u d d e n d e a t h f r o m H M E have also been r e p o r t e d . C T is the useful t o o l in the d e t e c t i o n o f the origin a n d extent o f spinal exostoses. H o w e v e r , M R I allows visuali z a t i o n o f the spinal cord, its c o m p r e s s i o n a n d i n t r a m e d u l l a r y changes s e c o n d a r y to c o m p r e s s i o n . C o m p l e t e r e m o v a l o f the exostoses a n d d e c o m p r e s s i o n o f the spinal c o r d is the t r e a t m e n t for H M E causing spinal c o r d c o m p r e s s i o n a n d u s u a l l y a s s o c i a t e d with a g o o d o u t c o m e . R e c u r r e n c e s after surgical resection o f spinal exostoses have n o t been r e p o r t e d , b u t occur in u p to 5% o f patients with e x t r a s p i n a l disease [2,15].
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