PATHOPHYSIOLOGY Incomplete Spinal Cord Injury (Central Spinal Cord Syndrome; Mild Disc Bulging in Cervical Spine) Risk Factors:
Predisposing Factors:
Gender (Female 20%)
Age (15 – 35 y/o are most affected)
Sports activity/participation activity/participation in risky physical activity
Falls (22%)
Etiology: Common mechanisms of SCI from traumatic impact include (1) hyperextension, (2) hyper hyper flexion flexion injuries injuries,, frequentl frequently y accompan accompanied ied by (3) rotation rotational al movements movements,, (4) vertical compression, compression, or (5) lateral flexion. Penetrating wounds such a missile trauma or stab wounds are commonplace. Primary and secondary injuries similar to those occurr occurring ing to the brain brain can can also also occur occur to the spi spinal nal cord, cord, includ including ing concus concussio sion, n, contusion, hemorrhage, laceration, eschemia, and edema. Asso Associ ciat ated ed vert verteb ebra rall inju injuri ries es may may lead lead to spin spinal al cord cord dama damage ge in subl sublux uxat atio ion n (incomple (incomplete), te), compress compression ion fracture fractures s and fracture fracture dislocat dislocations ions and other vertebra vertebrall injuries. The extent of cord damage in vertebral injury is related to the degree of bony Fal
Traumatic impact on cervical spine damaging inter vertebral disc Tears in the annulus (outer rings)
Fluid content of nucleus pulposus leak through some torn annular fibers Mild inter-vertebral inter-vertebral disc bulging on C4-C5, C5-C6 Bulging puts pressure on surrounding ligaments
Functions: C4: Upper body muscles (e.g. Deltoids, Biceps, Trapezius) C5: (1) Primary Motor: Shoulder Abduction, Elbow Flexion (2) Sensation: Lateral Arm (3) Reflex: Biceps C6: (1) Primary Motor: Wrist Extension (2) Sensation: Lateral Forearm, Thumb, and
Intrusion into the spinal canal Pain Affects spinal function
Impaired/Loss of function, such as mobility or sensation Weakness in upper extremities > Hemiparesis
C4: Results in significant loss of function at the biceps and shoulders. Also affects function of diaphragm and intercostals muscles which may be obliterated in very severe injuries. C5 : Full inervation of sternocleidomastoid, sternocleidomastoid, trapeziuz and other muscles: therefore neck, scapula and shoulder movement is retained. C6 : Complete innervations of the rotator muscles of the shoulder is
Quadriplegia, Quadriplegia, incomplete 31.2% - Paraplegia, complete 28.2% - Paraplegia, incomplete 23.1% Quadriplegia, Quadriplegia, complete 17.5% An incomplete spinal cord injury is the term used to describe damage to the spinal cord that is not absolute. The incomplete injury injury will vary enormously enormously from person person to person and will be entirely dependant on the way the spinal cord has been compromised.
Central Cord Syndrome: is when the damage is in the centre of the spinal cord. This typically results in he loss of function in the arms, but some leg movement may be preserved. There may also be some control over the bowel and bladder preserved. It is possible for some recovery from this type of injury, usually usually starting in the legs, legs, gradually progressing progressing upwards. upwards. This is a type of incomplete spinal cord injury
Motor strengths and sensory testing
The extent of injury is defined by the ASIA Impairment Scale (modified from the Frankel classification), using the following categories1,2 : • •
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A - Complete: No sensory or motor function is preserved in sacral segments S4-S5. S4-S5.4 B - Incomplete: Sensory, but not motor, function is preserved below the neurologic level and extends through sacral segments S4-S5. C - Incomplete: Motor function is preserved below the neurologic level, and most key muscles below the neurologic level have muscle grade less than 3. D - Incomplete: Motor function is preserved below the neurologic level, and most key muscles below the neurologic level have muscle grade greater than or equal to 3. E - Normal: Sensory and motor functions are normal.