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Seizure-induced thoracic spine compression fracture
Seizure-Induced Thoracic Spine Compression Fracture CASE REPORT Toshiyuki Takahashi, M.D.,* Teiji Tominaga, M.D.,* Hiroshi Shamoto, M.D.,* Hiroaki Shimizu, M.D.,* and Takashi Yoshimoto, M.D.† *Departments of Neurosurgery, Kohnan Hospital and †Tohoku University School of Medicine, Sendai, Japan
Takahashi T, Tominaga T, Shamoto H, Shimizu H, Yoshimoto T. Seizure-induced thoracic spine compression fracture: a case report. Surg Neurol 2002;58:214 –7.
sustained a seizure-induced thoracic compression fracture during inpatient video-electroencephalographic (EEG) monitoring.
BACKGROUND
Vertebral fracture caused solely by a convulsive seizure has rarely been reported in the neurosurgical literature. CASE DESCRIPTION
We describe a 34-year-old male with severe back pain from a thoracic fracture occurring in association with a seizure during hospitalization for treatment of temporal lobe epilepsy. Bone mineral densities in the lumbar spine and the femoral neck were decreased, possibly by longterm anti-epileptic medication. Muscle contractions during a seizure can result in vertebral fractures, especially at the thoracic levels. CONCLUSION
A complaint of back pain after a convulsive seizure should prompt radiologic investigation for vertebral fracture, even in the absence of external trauma. © 2002 by Elsevier Science Inc. KEY WORDS
Epilepsy, fracture, seizure, thoracic spine.
one fractures in epileptic patients may be associated with trauma either induced directly by a seizure or resulting from a fall or other accident resulting from the seizure [2,3,4,7,16]. In themselves, seizures can induce fractures of the femoral neck, humeral head, acetabulum, scapula, or vertebral column by violent contractions of skeletal muscles [3,8,10,13,15]. Seizure-induced vertebral fracture has been recognized, but has rarely been reported in the neurosurgical literature. We describe a patient with temporal lobe epilepsy who
B
Address reprint requests to: Dr Toshiyuki Takahashi, Department of Neurosurgery, Kohnan Hospital, 4 –20-1 Nagamachi-minami, Taihaku-ku, Sendai 982-8523, Japan. Received February 18, 2002; accepted May 30, 2002. 0090-3019/02/$–see front matter PII S0090-3019(02)00837-6
Case Report A 34-year-old male was admitted to our hospital for treatment of temporal lobe epilepsy. He had a history of intractable epilepsy from the age of 16 years and had received valproate, phenytoin, and carbamazepine, singly and in various combinations. During overnight video and EEG monitoring in our hospital, the patient complained of severe back pain after a generalized clonic convulsion lasting for minute. No accidental trauma accompanied this convulsion. Because of persistent severe back pain, thoracic spine radiographs were obtained 2 weeks later. These showed compression fractures at T6 and T7. The fractures also were evident on magnetic resonance (MR) images and on threedimensional computed tomography (3D-CT) (Figure 1). Moderate kyphosis was present at the levels of the fractures. Neurologically, hyperreflexia was noted in both lower extremities. Bone mineral densities measured by dual energy X-ray absorptiometry (Shimazu, Tokyo, Japan) were as follows: lumbar spine (L2 to L4), 0.800 g/cm2 (71% of the age-matched control value); right and left femoral neck, 0.879 and 0.883 g/cm2, respectively (87 and 88% of control). Three weeks after the fracture, the patient underwent right anterior temporal lobectomy and hippocampectomy for treatment of temporal lobe epilepsy. Postoperatively, seizures were well controlled with anti-epileptic drugs. As severe back pain persisted, spinal surgery was performed 17 days after epilepsy surgery to relieve back pain and © 2002 by Elsevier Science Inc. 360 Park Avenue South, New York, NY 10010 –1710
Seizure-Induced Vertebral Fracture
1
Surg Neurol 215 2002;58:214 –7
Three-dimensional computed tomographic (CT) image using bone window settings (left) and T1-weighted magnetic resonance (MR) imaging (right) of the thoracic spine showing compression fractures at T6 and T7.
to prevent further kyphotic deformity. The vertebrae at T6 and T7 were resected via a retropleural approach, autogenous iliac bone was grafted, and a Z-plate (Sofamor-Danek, Osaka, Japan) was used for fixation from T5 to T8. The postoperative course was uneventful. Postoperative MR images and radiographs indicated correction of the kyphotic deformity and rigid fixation (Figure 2).
Discussion The present case demonstrates that forceful muscle contractions during convulsive seizures can result in vertebral fractures without any external trauma. Kyphotic deformity of the thoracic spine after a seizure because of tetanus was observed in the early 1900s. Subsequently, electroconvulsive therapy in psychiatry and as well as seizures from epilepsy have been recognized as uncommon causes of compression fracture of the spine [6,13]. Symptomatic spinal fracture from a seizure is rare; its frequency of occurrence has been estimated at 1% of epileptic patients [13]. Vasconcelos reported that 15 of 1,487 epileptic patients had both complaints of back pain and radiologic evidence of one or more vertebral fractures [13]. However, the
reported prevalence of asymptomatic fracture associated with seizure is as high as 15 to 16%; Pedersen et al found asymptomatic vertebral fractures in 16% of 87 epileptic outpatients [10], and Vasconcelos found them in 11 of 70 epileptic patients (15%) [13]. Therefore, most vertebral fractures induced by seizure are inherently stable and neurologically silent. When a fracture is symptomatic, the patient usually complains of back pain alone, as in the present case. The most common fracture location is upper- to midthoracic (T3 to T8), in contrast to the thoracolumbar junction or the cervical spine fractures frequently found in patients with external trauma [8,13,15]. This distinctive distribution occurs because compressive forces during contraction of the muscles are concentrated along the anterior and middle columns of the midthoracic kyphotic curve [8,15]. Cervical fracture and lumbosacral dislocation have been documented on rare occasions [5,13]. Seizure-associated vertebral fractures occur primarily in adult males, although fractures in children receiving anti-epileptic drugs have been reported [4,9,10,13]. Notably, the fracture occurs during sleep in 40% of the patients with seizureinduced vertebral fractures [13]. These nocturnal
216 Surg Neurol 2002;58:214 –7
Takahashi et al
may be overlooked in patients with mild back pain. A complaint of back pain in epileptic patients raises a strong suspicion of vertebral fracture and should be evaluated radiologically.
REFERENCES
Postoperative radiograph (left) and T1-weighted magnetic resonance (MR) imaging (right) showing resection of the T6 and T7 vertebrae, iliac bone fusion, and fixation with a Z-plate system.
2
vertebral compression fractures presumably are indicative of unwitnessed convulsive seizures [1]. Anti-epileptic drugs are considered to increase fracture risk in epileptic patients through reduction of bone mineral density [9,11,12,13]. For instance, valproate reduces bone mineral density by 14% in the lumbar spine in children taking the drug for more than 18 months [4]. Phenytoin and carbamazepine also reduce bone mineral density, thereby increasing the risk of fracture [11,12,14]. In the present case, bone mineral density was decreased to less than the mean value minus one standard deviation in values from age-matched controls. We suspect that anti-epileptic drug therapy continuing for more than 10 years reduced our patient’s bone mineral density and thus made him susceptible to vertebral fracture, although direct evidence of reduced bone mineral density in the thoracic spine was not sought. In conclusion, forceful muscle contractions during a convulsive seizure can result in vertebral compression fracture, especially in the midthoracic region. Absence of external trauma and possible postictal consciousness disturbance may hinder early diagnosis. Further, vertebral fracture easily
1. Aboukasm AG, Smith BJ. Nocturnal vertebral compression fracture. A presenting feature of unrecognized epileptic seizures. Arch Fam Med 1997;6:185–7. 2. Buck D, Baker GA, Jacoby A, Smith DF, Chadwick DW. Patients experiences of injury as a result of epilepsy. Epilepsia 1997;38:439 – 44. 3. Finelli PF, Cardi JK. Seizure as a cause of fracture. Neurology 1989;39:858 – 60. 4. Gilles P, Alliet P, Bruneel E, Raes M. Effect of valproate on bone mineral density [letter; comment]. J Pediatr 1996;128:441. 5. Gra¨ be RP. Fracture-dislocation of the lumbosacral spine during a grand mal epileptic seizure. S Afr Med J 1988;74:129 –31. 6. Kelly JP. Fracture complicating electro-convulsive therapy and chronic epilepsy. J Bone Joint Surg (Br) 1954;36:70 –9. 7. Kumar SK, Freeman BJ. Quadriplegia following grand mal seizures. Injury 1999;30:626 –9. 8. McCullen GM, Brown CC. Seizure-induced thoracic burst fractures. A case report. Spine 1994;19:77–9. 9. Nilsson OS, Lindholm TS, Elmstedt E, Lindback A, Lindholm TC. Fracture incidence and bone diseases in epileptics receiving long-term anticonvulsant drug treatment. Arch Orthop Trauma Surg 1986;105:146 –9. 10. Pedersen KK, Christiansen C, Ahlgren P, Lund M. Incidence of fractures of the vertebral spine in epileptic patients. Acta Neurol Scand 1976;54:200 –3. 11. Sheth RD, Wesolowski CA, Jacob JC, et al. Effect of carbamazepine and valproate on bone mineral density. J Pediatr 1995;127:256 – 62. 12. Stephen LJ, McLellan AR, Harrison JH, et al. Bone density and antiepileptic drugs: a case-controlled study. Seizure 1999;8:339 – 42. 13. Vasconcelos D. Compression fractures of the vertebrae during major epileptic seizures. Epilepsia 1973; 14:323– 8. 14. Vestergaad R, Tigaran S, Rejnmark L, Tigaran C, Dam M, Mosekilde L. Fracture risk is increased in epilepsy. Acta Neurol Scand 1999;99:269 –75. 15. Youssef JA, McCullen GM, Brown CC. Seizure-induced lumbar burst fracture. Spine 1995;20:1301–3. 16. Zwimper TJ, Brown J, Sullivan R, Moulton RJ. Head injuries due to falls caused by seizure: a group at high risk for traumatic intracranial hematomas. J Neurosurg 1997;86:433–7.
COMMENTARY
This article describes a not-uncommon complication of epilepsy. It is, however, unusual for a patient to suffer a significant thoracic compression fracture requiring surgical stabilization in this context. The
Takahashi T, Tominaga T, Shamoto H, Shimizu H, Yoshimoto T. Seizure-induced thoracic spine compression fracture: a case report. Surg Neurol 2002;58:214 –7.
sustained a seizure-induced thoracic compression fracture during inpatient video-electroencephalographic (EEG) monitoring.
BACKGROUND
Vertebral fracture caused solely by a convulsive seizure has rarely been reported in the neurosurgical literature. CASE DESCRIPTION
We describe a 34-year-old male with severe back pain from a thoracic fracture occurring in association with a seizure during hospitalization for treatment of temporal lobe epilepsy. Bone mineral densities in the lumbar spine and the femoral neck were decreased, possibly by longterm anti-epileptic medication. Muscle contractions during a seizure can result in vertebral fractures, especially at the thoracic levels. CONCLUSION
A complaint of back pain after a convulsive seizure should prompt radiologic investigation for vertebral fracture, even in the absence of external trauma. © 2002 by Elsevier Science Inc. KEY WORDS
Epilepsy, fracture, seizure, thoracic spine.
one fractures in epileptic patients may be associated with trauma either induced directly by a seizure or resulting from a fall or other accident resulting from the seizure [2,3,4,7,16]. In themselves, seizures can induce fractures of the femoral neck, humeral head, acetabulum, scapula, or vertebral column by violent contractions of skeletal muscles [3,8,10,13,15]. Seizure-induced vertebral fracture has been recognized, but has rarely been reported in the neurosurgical literature. We describe a patient with temporal lobe epilepsy who
B
Address reprint requests to: Dr Toshiyuki Takahashi, Department of Neurosurgery, Kohnan Hospital, 4 –20-1 Nagamachi-minami, Taihaku-ku, Sendai 982-8523, Japan. Received February 18, 2002; accepted May 30, 2002. 0090-3019/02/$–see front matter PII S0090-3019(02)00837-6
Case Report A 34-year-old male was admitted to our hospital for treatment of temporal lobe epilepsy. He had a history of intractable epilepsy from the age of 16 years and had received valproate, phenytoin, and carbamazepine, singly and in various combinations. During overnight video and EEG monitoring in our hospital, the patient complained of severe back pain after a generalized clonic convulsion lasting for minute. No accidental trauma accompanied this convulsion. Because of persistent severe back pain, thoracic spine radiographs were obtained 2 weeks later. These showed compression fractures at T6 and T7. The fractures also were evident on magnetic resonance (MR) images and on threedimensional computed tomography (3D-CT) (Figure 1). Moderate kyphosis was present at the levels of the fractures. Neurologically, hyperreflexia was noted in both lower extremities. Bone mineral densities measured by dual energy X-ray absorptiometry (Shimazu, Tokyo, Japan) were as follows: lumbar spine (L2 to L4), 0.800 g/cm2 (71% of the age-matched control value); right and left femoral neck, 0.879 and 0.883 g/cm2, respectively (87 and 88% of control). Three weeks after the fracture, the patient underwent right anterior temporal lobectomy and hippocampectomy for treatment of temporal lobe epilepsy. Postoperatively, seizures were well controlled with anti-epileptic drugs. As severe back pain persisted, spinal surgery was performed 17 days after epilepsy surgery to relieve back pain and © 2002 by Elsevier Science Inc. 360 Park Avenue South, New York, NY 10010 –1710
Seizure-Induced Vertebral Fracture
1
Surg Neurol 215 2002;58:214 –7
Three-dimensional computed tomographic (CT) image using bone window settings (left) and T1-weighted magnetic resonance (MR) imaging (right) of the thoracic spine showing compression fractures at T6 and T7.
to prevent further kyphotic deformity. The vertebrae at T6 and T7 were resected via a retropleural approach, autogenous iliac bone was grafted, and a Z-plate (Sofamor-Danek, Osaka, Japan) was used for fixation from T5 to T8. The postoperative course was uneventful. Postoperative MR images and radiographs indicated correction of the kyphotic deformity and rigid fixation (Figure 2).
Discussion The present case demonstrates that forceful muscle contractions during convulsive seizures can result in vertebral fractures without any external trauma. Kyphotic deformity of the thoracic spine after a seizure because of tetanus was observed in the early 1900s. Subsequently, electroconvulsive therapy in psychiatry and as well as seizures from epilepsy have been recognized as uncommon causes of compression fracture of the spine [6,13]. Symptomatic spinal fracture from a seizure is rare; its frequency of occurrence has been estimated at 1% of epileptic patients [13]. Vasconcelos reported that 15 of 1,487 epileptic patients had both complaints of back pain and radiologic evidence of one or more vertebral fractures [13]. However, the
reported prevalence of asymptomatic fracture associated with seizure is as high as 15 to 16%; Pedersen et al found asymptomatic vertebral fractures in 16% of 87 epileptic outpatients [10], and Vasconcelos found them in 11 of 70 epileptic patients (15%) [13]. Therefore, most vertebral fractures induced by seizure are inherently stable and neurologically silent. When a fracture is symptomatic, the patient usually complains of back pain alone, as in the present case. The most common fracture location is upper- to midthoracic (T3 to T8), in contrast to the thoracolumbar junction or the cervical spine fractures frequently found in patients with external trauma [8,13,15]. This distinctive distribution occurs because compressive forces during contraction of the muscles are concentrated along the anterior and middle columns of the midthoracic kyphotic curve [8,15]. Cervical fracture and lumbosacral dislocation have been documented on rare occasions [5,13]. Seizure-associated vertebral fractures occur primarily in adult males, although fractures in children receiving anti-epileptic drugs have been reported [4,9,10,13]. Notably, the fracture occurs during sleep in 40% of the patients with seizureinduced vertebral fractures [13]. These nocturnal
216 Surg Neurol 2002;58:214 –7
Takahashi et al
may be overlooked in patients with mild back pain. A complaint of back pain in epileptic patients raises a strong suspicion of vertebral fracture and should be evaluated radiologically.
REFERENCES
Postoperative radiograph (left) and T1-weighted magnetic resonance (MR) imaging (right) showing resection of the T6 and T7 vertebrae, iliac bone fusion, and fixation with a Z-plate system.
2
vertebral compression fractures presumably are indicative of unwitnessed convulsive seizures [1]. Anti-epileptic drugs are considered to increase fracture risk in epileptic patients through reduction of bone mineral density [9,11,12,13]. For instance, valproate reduces bone mineral density by 14% in the lumbar spine in children taking the drug for more than 18 months [4]. Phenytoin and carbamazepine also reduce bone mineral density, thereby increasing the risk of fracture [11,12,14]. In the present case, bone mineral density was decreased to less than the mean value minus one standard deviation in values from age-matched controls. We suspect that anti-epileptic drug therapy continuing for more than 10 years reduced our patient’s bone mineral density and thus made him susceptible to vertebral fracture, although direct evidence of reduced bone mineral density in the thoracic spine was not sought. In conclusion, forceful muscle contractions during a convulsive seizure can result in vertebral compression fracture, especially in the midthoracic region. Absence of external trauma and possible postictal consciousness disturbance may hinder early diagnosis. Further, vertebral fracture easily
1. Aboukasm AG, Smith BJ. Nocturnal vertebral compression fracture. A presenting feature of unrecognized epileptic seizures. Arch Fam Med 1997;6:185–7. 2. Buck D, Baker GA, Jacoby A, Smith DF, Chadwick DW. Patients experiences of injury as a result of epilepsy. Epilepsia 1997;38:439 – 44. 3. Finelli PF, Cardi JK. Seizure as a cause of fracture. Neurology 1989;39:858 – 60. 4. Gilles P, Alliet P, Bruneel E, Raes M. Effect of valproate on bone mineral density [letter; comment]. J Pediatr 1996;128:441. 5. Gra¨ be RP. Fracture-dislocation of the lumbosacral spine during a grand mal epileptic seizure. S Afr Med J 1988;74:129 –31. 6. Kelly JP. Fracture complicating electro-convulsive therapy and chronic epilepsy. J Bone Joint Surg (Br) 1954;36:70 –9. 7. Kumar SK, Freeman BJ. Quadriplegia following grand mal seizures. Injury 1999;30:626 –9. 8. McCullen GM, Brown CC. Seizure-induced thoracic burst fractures. A case report. Spine 1994;19:77–9. 9. Nilsson OS, Lindholm TS, Elmstedt E, Lindback A, Lindholm TC. Fracture incidence and bone diseases in epileptics receiving long-term anticonvulsant drug treatment. Arch Orthop Trauma Surg 1986;105:146 –9. 10. Pedersen KK, Christiansen C, Ahlgren P, Lund M. Incidence of fractures of the vertebral spine in epileptic patients. Acta Neurol Scand 1976;54:200 –3. 11. Sheth RD, Wesolowski CA, Jacob JC, et al. Effect of carbamazepine and valproate on bone mineral density. J Pediatr 1995;127:256 – 62. 12. Stephen LJ, McLellan AR, Harrison JH, et al. Bone density and antiepileptic drugs: a case-controlled study. Seizure 1999;8:339 – 42. 13. Vasconcelos D. Compression fractures of the vertebrae during major epileptic seizures. Epilepsia 1973; 14:323– 8. 14. Vestergaad R, Tigaran S, Rejnmark L, Tigaran C, Dam M, Mosekilde L. Fracture risk is increased in epilepsy. Acta Neurol Scand 1999;99:269 –75. 15. Youssef JA, McCullen GM, Brown CC. Seizure-induced lumbar burst fracture. Spine 1995;20:1301–3. 16. Zwimper TJ, Brown J, Sullivan R, Moulton RJ. Head injuries due to falls caused by seizure: a group at high risk for traumatic intracranial hematomas. J Neurosurg 1997;86:433–7.
COMMENTARY
This article describes a not-uncommon complication of epilepsy. It is, however, unusual for a patient to suffer a significant thoracic compression fracture requiring surgical stabilization in this context. The