Cervical Radiographic Study in Adolescence Cerebral Palsy

OBJECTIVE: To study the incidence and degree of the cervical instability in the cerebral palsied patients and to investigate the cause of the high incidence of cervical myelopathy in these patients. METHOD: The static and dynamic radiography of the cervical spine in the sagittal plane was performed in seventy-two patients with athetoid and spastic cerebral palsy and the incidence of spondylolisthesis, range of motion(by the Penning Method), sagittal diameter of the cervical canal, and posture of the cervical spine were evaluated. RESULTS: The incidence of the cervical spondylolisthesis was fifty percent with athetoid cerebral palsy and twenty-seven percents with spastic cerebral palsy. The incidence of spondylolisthesis was especially high at the level of C3/4 and C4/5. The excessive range of motion in flexion/extension by the sagittal plane was observed in 66.7% of athetoid patients and 53.3% of spastic patients, especially at the C2/3 and C3/4 levels. The abnormal curvature was noted in 66.6% of athetoid and spastic patients. C-curve and S-curve were more common in athetoid patients and straightening of the C-spine was more common in spastic type. A sagittal diameter of the cervical spinal canal was significantly decreased in patients with athetoid patients with C3/4 spondylolisthesis and/or abnormal curvature such as a C-curve or S-curve(P<0.05). Height of the vertebral body was decreased in both athetoid and spastic patients. CONCLUSION: The combination of a cervical instability and a narrow spinal canal predisposes the neurological progression to a cervical myelopathy in cerebral palsied patients.

Hyperthermal Injury of the Peripheral Nerve: Electrophysiologic and Histopathologic Study

OBJECTIVE: To investigate the electrophysiologic and histopathologic changes of the prheral nerve from hyperthermal nerve injury and to observe the difference of these changes according to the level of temperature and the duration of heat application. METHOD: The experimental rats (Sprague-Dawley) were divided into four groups according to the degree of temperature and the duration of heat application : Group 1, 43degrees C for 15 min; Group 2, 43degrees C for 30 min; Group 3, 45degrees C for 15 min; Group 4, 45degrees C for 30 min. A segment of 5 mm of the sciatic nerve was exposed and treated in vivo with local hyperthermia using a thermostatically controlled heating unit. For the electrophysiologic examination, both sciatic nerve conduction study and needle electromyographic examination were performed immediately before, and at 1 day, 3 days, 1 week, 2 weeks, and 4 weeks after the hyperthermia. For the histopathologic study, a sciatic nerve biopsy was performed at 1 day, 1 week, 2 weeks, and 4 weeks after the hyperthermia and the changes were investigated under the light microscopic and electronmicroscopic examinations. RESULTS: In experimental groups, the compound muscle action potentials (CMAPs) showed a significant reduction compared to the control group (p<0.05). Amplitudes of CMAPs following the heat application to the nerve were inversely related with the degree and duration of hyperthermia. A significant recovery of CMAPs was observed at 4 weeks after the hyperthermia in all experimental groups. The motor conduction latencies, however, did not show any significant changes. The needle electromyography of the gastrocnemius began to reveal fibrillation potentials on the 3rd day after the hyperthermia and continued to appear until the second week and then completely disappeared at 4 weeks after the hyperthermia. The histopathologic findings began to show the degeneration of axon and myelin within 24 hours and a remarkable regeneration at 4 weeks after the hyperthermia. CONCLUSION: The results revealed that the hyperthermia of peripheral nerve within the range of 43~45degrees C for 15~30 min is likely to cause a significant acute, but not necessarily permanent nerve injury, and the severity of nerve injuries is related to the temperature and duration of heat applications. Whether the results can be clinically applied to human beings would require further exploration.

Clinical Features of Cerebral Palsy

Cerebral palsy is a non-progressive cerebral sensori-motor defect, acquired either prenatally or in an early life and evolves over the first few years. Until recently many people believed that asphyxia at birth was a major cause of cerebral palsy and that the prevention of asphyxia at birth by improving perinatal care would reduce the number of cerebral palsy children. However the incidence of cerebral palsy in children has remained steady or ever risen slightly. The real cause of cerebral palsy is still unbaron to us. This analysis was undertaken to determine the clinical features of cerebral palsy in Korea by the retrospective study of 98 children. Over a half of infants with cerebral palsy (64.2%) was recognized by parents before 1 year of corrected age, and their chief complaints were delayed developments or equinus foot deformities. The most common type of cerebral palsy was spastic type (64.2%) which was followed by athetoid (10.5%), ataxia and hypotonia types (4.2% each). The mixed type was 19.4% Among 98 cerebral palsies, the preterm infants were 42.9% and the infants with low birth weight were 41.4%. The cerebral palsies with low birth weight and preterm infants were more likely to have spastic diplegia. The most frequent abnormal primitive reflex was absent protective extension(78.3%). No significant associations of the type of cerebral palsy with primitive reflexes were found. An increased risk of cerebral palsy with increased maternal age was not observed in this study. Of 55 MRI findings, no abnormalities were seen in 27.2%, periventricular leukomalacias in 34.5%, brain atrophies in 21.8%, cerebral infarcts in 10.9%, intracerebral hemorrhage in 3.6%, and delayed myelinations in 1.8%. The periventricular leukomalacias were associated with the preterm infants in 63.2%.