Clinical & imaging diagnosis
Case 123
【Progress】She was admitted in our hospital to receive physical rehabilitation. At the time 10 days after admission, she felt no pain, but felt touch well in the left lower extremity below L4. She could move contraction of left lower extremity below L5. She could feel urination but not evacuation of stools. She was scheduled to have rehabilitation for three months.
【Discussion】
There are 31 segments in the spinal cord (8; cervical cord, 12; thoracic cord; 5 lumbar cord; 5 sacral cord; 1 coccygeal cord). Although the detail structure of spinal cord varies dependent on the sites of the cross section, each cord has grey matter and white matter. The grey matter is included in the gelatin substance in the center of the spinal cord, which is butterfly-shaped. The main function of the spinal cord is spinal reflex of muscle tension and muscle repression, working in this gelatin substance. The butterfly shaped grey matter is composed of anterior grey column and posterior grey column. Anterior grey column affects skeletal muscles and posterior grey column receives information of sensation such as pain and touch.
Anterior horn (nerve root) cells in anterior grey column play a key role of motor reflex. They connect with pyramidal tract and extrapyramidal tract, and work to coordinate with central motor centers of cerebrum and cerebellum. As pyramidal tract coming from cerebral cortex, lateral cortico-spinal tract (pyramidal decussation [crossing] axons) and anterior cortico-spinal tract (not crossing axons) are listed. As extra-pyramidal tract, rubro-spinal tract, olivo-spinal tract and vestibulo-spinal tract originally coming from cerebellum, and reticulo-spinal tract from brain stem are listed. These motor tracts are arranged surrounding anterior horn cells.
Posterior grey gelatin substances compose of neuro-fibers which divides to anterior horn and ascending tract as sensation pathways. Sensation pathways to the central nerve center are categorized into cerebrum via thalamus and cerebellum. There are several kinds of sensations: position, pressure, vibration, pain, temperature, touch. These sensations are transmitted to thalamus (finally cerebral cortex) via the different tracts. In short, position, pressure and vibration are transmitted through fasciculus gracillis (lower extremity below Th6) and fasciculus cuneatus (upper extremity Th6 or upper) which are the most prominent pathway in the posterior column. Pain and temperature are transmitted through lateral spinothalamic tract. Touch is transmitted through anterior spinothalamic tract. Further, the same information of these sensations is transmitted to cerebellum at the same time through dorsal and ventral spinocerebellar tract.
The sensations of L4 to S3 are transmitted to cerebellum via superior cerebellar peduncle through ventral spinocerebellar tract and those of Th1 to L3 to cerebellum via inferior cerebellar peduncle through dorsal spinocerebellar tract.
Spinal cord syndrome caused by spinal injury is categorized into central cord syndrome, anterior cord syndrome, posterior cord syndrome and Brown-Sequard syndrome (hemi-lateral injury). In central spinal cord syndrome, upper extremity is more susceptible to damage than lower extremity, irrespective of motor tract and sensory tract. Injury to C1 to C4 is the most severe of the spinal injuries because the phrenic nerve is formed from C3 to C5 nerve fibers. Patients might not able to breath on her or his own. In our case, MRI showed central cord injury at the level of C3 and partial injury at the level from C4 and C5. She experienced quadriplegia and preserved respiratory function.
The causes of central cord injury include falls, vehicle accidents, spinal cord impingement by spinal canal stenosis, tumor or vertebral disk. The causes of anterior spinal canal injury which spares sensation of position, pressure and touch, occur disk herniation or occlusion of anterior spinal artery. The causes of posterior spinal cord syndrome are tabes dorsalis by syphilis and vitamin deficiency rather than trauma resulting in loss of sensation of position, pressure and touch. Brown- Sequard syndrome occurs due to penetrating wounds such as gunshot and knife insertion, resulting in ipsilateral disorder of motor and sensory function. In our case, she fell down from a wheel chair, causing central spinal cord syndrome.
【Summary】
We present a ninety one-year-old female who had central spinal cord injury caused by fell down from a wheel chair, resulting in quadriplegia. We should keep in mind that there are 31 segments in the spinal cord (8; cervical cord, 12; thoracic cord; 5 lumbar cord; 5 sacral cord; 1 coccygeal cord). Each section of the spinal cord has butterfly shaped-gray matter in the center where the spinal reflex acts. Anterior horn cells not only work spinal reflex but also work to coordinate with central motor centers of cerebrum and cerebellum via pyramidal tract (lateral cortico-spinal tract and anterior cortico-spinal tract and extra pyramidal tracts: rubro-spinal tract, olivo-spinal tract and vestibulo-spinal tract originally coming from cerebellum, and reticulo-spinal tract from brain stem). Sensation pathways to the central nerve center are categorized into cerebrum via thalamus and cerebellum. Position, pressure and vibration are transmitted through fasciculus gracillis (lower extremity below Th6) and fasciculus cuneatus (upper extremity Th6 or upper), pain and temperature are transmitted through lateral spinothalamic tract, touch is transmitted through anterior spinothalamic tract. The sensations of L4 to S3 are transmitted to cerebellum via superior cerebellar peduncle through ventral spinocerebellar tract and those of Th1 to L3 to cerebellum via inferior cerebellar peduncle through dorsal spinocerebellar tract. Spinal cord syndrome caused by spinal injury is categorized into central cord syndrome, anterior cord syndrome, posterior cord syndrome and Brown-Sequard syndrome (hemi-lateral injury).
【References】
The content of this article is written by the book as below.
Peter Duus. Neuroloigisch-topische Diagnostik: Anatomie Physiologie Klinik, second edition translated in Japanese by Hajime Handa and Junya Hanakita. Bunkodo, Tokyo
2018.10.3