The spine, which serves as the weight-bearing structure of the body, is comprised of segments of bones (vertebrae) surrounding protective discs. The spine has four segments: the cervical, thoracic, lumbar, and sacral.
The basic types of spinal fractures include: 1) vertebral compression fractures, 2) vertebral burst fractures (a more serious compression fracture), and 3) fracture-dislocations, which involve significant damage to the facet joints. More minor or uncommon fractures consist of laminar or spinous process fractures (both of these structures are located in the posterior column, known as the third column of the spine). Another minor or uncommon fracture is to the transverse process. (There are two transverse processes on each side of the vertebral body).
The most common fractures of the spine occur in the thoracic (midback) and lumbar spine (lower back) or at the connection of the thoracic and lumbar spine (called the thoracolumbar junction). These fractures are typically caused by high-velocity accidents, such as a car crash or fall from heights.
Men experience fractures of the thoracic or lumbar spine four times more often than women. Seniors are also at risk for these fractures due to weakened bone mass as a result of osteoporosis. The primary causes of spinal fractures are car accidents (45%), falls (20%), sports (15%), acts of violence (15%), and miscellaneous activities (5%).
Diseases such as spine tumors also contribute to fractures. Other associated causes of fractures may be tied to injuries of the spinal cord, nerve roots or the group of nerve roots at the end of the spinal cord, called the cauda equina.
Symptoms of spinal fractures can include the following, depending on location and type of fracture:
Neurogenic shock – Serious result of injury to spinal cord, this is a life-threatening medical condition in which there is insufficient blood flow throughout the body.
A significant traumatic spinal fracture may cause a spinal cord injury. Spinal shock, a complication of injury to the brain or spinal cord, is the temporary loss of spinal reflex activity that occurs below a total or near-total spinal cord injury.
Major fractures can result in serious long-term problems unless treated promptly and properly. Surgery is necessary in various other circumstances, such as injury that results in instability of the spine. Surgical repair is also indicated when painful compression fractures persist, such as from osteoporosis.
Spondylolisthesis is a spinal condition in which one of the vertebra slips forward or backward compared to the next vertebra. Forward slippage of an upper vertebra on a lower vertebra is called anterolisthesis, and backward slippage is referred to as retrolisthesis. Spondylolisthesis can lead to a deformity of the spine, as well as a narrowing of the spinal canal (central spinal stenosis) or compression of the exiting nerve roots (foraminal stenosis).
There are various types of spondylolisthesis. These include: dysplastic spondylolisthesis, a congenital condition (i.e. a condition that is present at birth). It is caused by a defect in the formation of a part of the vertebra, called the facet, that allows it to slip forward.
Isthmic spondylolisthesis, which leads to small stress fractures in the vertebrae, can be caused by repetitive trauma. This is more common in athletes who perform hyperextension motions, such as linemen in football and gymnasts.
Degenerative spondylolisthesis is the most common form, and occurs due to arthritic changes and cartilage degeneration in the joints of the vertebrae. Degenerative spondylolisthesis commonly occurs in those over age 40.
Less common types of spondylolisthesis include:
- Traumatic spondylolisthesis, which is due to direct trauma or injury to the vertebrae. This can be caused by a fracture or slipping of the vertebra.
- Pathologic spondylolisthesis, which is caused by abnormal bone, resulting from such causes as a tumor, Paget’s disease, or tuberculosis.
Symptoms of spondylolisthesis include:
- Lower back or leg pain
- Hamstring tightness
- Numbness and tingling in the legs or feet
Surgery may be indicated for patients with a grade 3 (50%-75% slippage) or grade 4 spondylolisthesis (more than 75% slippage), as well as for patients with severe pain and inability to function who have not gotten better after at least three to six months of non-surgical treatment.
Spinal Cord Injuries
Spinal Cord Injury (SCI) is damage to the spinal cord that results in a loss of function below the level of the injury or wound. SCI most commonly occurs following trauma. However, there are other causes including pathologic fractures (i.e. fractures caused by weakening of the bone, such as from the variety of diseases which lead to this problem), spinal tumors, spinal infections, and congenital spinal anomalies.
Current estimates indicate that between 250,000 and 400,000 people in the U.S. are living with a spinal cord injury or spinal dysfunction. Ten thousand new SCI’s occur each year, of which the majority (82%) are males between the ages of 16-30. Spinal trauma typically results from motor vehicle accidents, violent acts and falls.
SCI can be divided into two types: complete and incomplete. The type of SCI is important in the prognosis and return of function. A complete injury means that there is no function below the level of the injury. This means the absence of any sensation and no voluntary movement. An incomplete injury means that there is some function below the primary level of the injury. With an incomplete injury, a person may be able to feel parts of the body (even if they cannot be moved) or move a limb. Complete injuries tend to have little recovery, while incomplete injuries usually have some degree of improvement.
Symptoms of spinal cord injury include:
- Severe pain and/or pressure in the back, neck, or head
- Difficulty breathing
- Numbness/tingling or lack of ability to feel sensations such as heat, cold, or touch
- Partial or complete loss of control over any part of the body
- Loss of reflexes
- Loss of/or changes in normal bowel and bladder control/function
- Difficulty with walking and/or balance
- Unusual pain, pressure sensations in the trunk
- Abnormal lumps or bumps on the head or spine
- Exaggerated reflexes or muscle spasms
- Sensitivity to stimuli
- Changes in sexual function
Surgery to treat spinal cord injury (SCI) may be performed immediately after the injury, or at a later time. Urgent surgery is more common with an incomplete SCI.
Surgery is indicated when there is significant instability of the spine or if there is compression of the spinal cord with an incomplete SCI. Decompression is used to address conditions compressing the spinal cord such as a herniated disc, fracture, infection, blood or fluid build-up, or a tumor. Spinal stabilization is done if the spine needs to be re-aligned or stabilized, meaning that instrumentation (such as rods, screws and cages) and fusion is necessary. While surgery may not reverse spinal cord damage, it can also be necessary to prevent further problems such as pain or deformity, or to halt the progression of neurological problems such as weakness, tingling, or bowel/bladder problems.