SPINAL CORD INFARCTION
Fibrocartilaginous embolization of the spinal cord is a functional equivalent of a stroke (infarction) to the spinal cord rather than the brain. The events are acute (instantaneous), nonprogressive, and occur without any prior signs or warnings. Because they can occur in any portion of the cord, clinical signs can involve the rear limbs, all four limbs, one side of the body or only one limb. The syndrome is NOT painful, but can result in a profound paralysis. After the initial "spinal cord shock" subsides, one side of the body frequently remains worse or is slower to show improvement.
In a spinal cord fibrocartilaginous embolization, the stroke, or infarction, is due to a small fragment of intervertebral disc material entering the cords vascular system via the tissues attached to the disc (Fig.1&2). This tiny fragment of disc material results in varying degrees of damage, depending on the portion of the cord supplied by the embolized vessel. Thus, the clinical signs are variable.
In general, if deep pain perception is intact to the paralyzed limb(s), recovery will begin in two to three weeks with most clinical function restored by four months. In most cases, once the diagnosis and degree of clinical damage is ascertained, an accurate prognosis can be made.
A tentative diagnosis of a fibrocartilaginous embolism is made based on history and neurologic examination. Radiographs (x-rays) are evaluated to ascertain the presence of degenerative discs and may outline other abnormalities in the spine, including fractures and dislocations. A definitive diagnosis may require a special x-ray test called a myelogram ( a contrast dye study of the spine). The purpose of this procedure is to delineate the spinal cord on radiographs. Spinal cord swelling may be seen with a myelogram immediately after an infarction (Fig.3). If several days have passed since the onset of the clinical signs, the myelogram will be normal. Other differential diagnoses delineated on a myelogram include intervertebral disc extrusions, tumors, fractures, hematomas, and hemorrhage. With new gas anesthetics, advanced monitoring equipment, and modern "contrast" agents for the dye study, the myelogram and concurrent cerebrospinal fluid analysis are now a common and safe diagnostic procedure when performed with care and under the proper conditions.
Individuals experiencing an acute episode of a fibrocartilaginous embolism are immediately treated once the diagnosed is confirmed. Intensive medical therapies are of value only during the first 24 to 48 hours after the spinal cord damage has occurred. The medications used include corticosteroids (cortisones) to relieve the spinal cord swelling and to prevent collateral damage. Surgery is not indicated in the treatment of spinal cord infarction. After the initial medical management, intensive nursing care and physical therapy are continued. The goal is to maintain muscle tone while the spinal cord tissue heals.
The prognosis in cases of fibrocartilaginous embolization depends on many factors:
1) the severity of
In general the ability to perceive deep pain in the affected limbs and tail remain the major prognostic indicator. Even if paralysis is complete, the perception of deep pain remains the key to determining if permanent damage has occurred. This means that in spite of a profound and devastating paralysis, if the conscious perception of deep pain is intact, a functional recovery is anticipated. While the time required for recovery and the degree of neurologic improvement is quite variable, diligent physical therapy and good nursing care remain the keys to recovery.
1998, Southern California Veterinary Surgical Group