The lumbar spine is located in the lower back below the cervical and thoracic sections of the spine. It consists of five vertebrae known as L1 - L5. These lumbar vertebrae contain spinal cord tissue and nerves which control communication between the brain and the legs. Damage to the lumbar spinal cord subsequently affects the hips and groin area, and may impact the lower abdominal muscles and thigh flexion as well.
Lumbar spinal cord damage may be complete or incomplete and may affect one or both sides of the body. As is the case with other spinal cord injuries, the completeness of the spinal cord damage will determine how severe the injury and symptoms will be for the patient.
It is also important to understand that the lumbar vertebrae are much different than the upper segments of the spine because the spinal cord does not extend the entire length of the lumbar spine. L2 is the lowest vertebral segment that contains spinal cord tissue. After that point, nerve roots exit each of the remaining lumbar levels beyond the spinal cord.
Injuries below this level (at the L3, L4, and L5 vertebrae) affect the hips and legs and may cause numbness extending to the feet (sciatica). It may also harm the tip of the spinal cord known as the caudal equina, which is a bundle of spinal nerves and nerve roots that innervate the lower lumbar spine to the sacrum.
As a fetus, vertebral segments directly relate to spinal cord segments. As an adult, the spinal column grows longer than the spinal cord and they no longer relate to one another. The spinal cord ends around the L1 or L2 vertebrae in adults, forming the conus medullairs. The horsetail shaped area, which extends past the conus medullairs, is the cauda equina.
Injuries to the lumbar spine are severe but not life-threatening. Early treatment is important to the prognosis of lumbar spinal cord damage. Patients with a lumbar spinal cord injury can be independent and care for their own mobility and hygienic needs. Many patients are able to maneuver around in their manual wheelchair and may even be able to walk for short distances. Weakness is the main issue with patients who experience lumbar nerve injuries, so physical therapy is a must in the recovery phase.
Cauda equina syndrome (CES), which is often difficult to distinguish from the similarly-located conus medullaris syndrome, affects the lumbar spine and is considered a medical emergency. CES affects the nerves of the lumbar spine, which may cause incontinence and potentially permanent paralysis of the legs. Patient’s symptoms may come on slowly, but once it is diagnosed, it requires immediate surgery.
Patients with lumbar spinal cord injuries may experience:
The most common causes spinal cord injuries at the lumbar level are:
Current treatments available for spinal cord patients with lumbar injuries are:
Damaging the spinal cord in the lumbar region should leave the patient with full upper body strength and mobility. Although the use of a wheelchair may be necessary, these patients go on to live fairly normal lives and are able to care for most of their own needs. Lumbar spinal cord injury patients may even go on to drive modified cars.