Pars Fracture

Spondylolysis

Spondylolysis is a stress fracture of vertebra that may progress into spondylolisthesis, a condition of displacement of vertebrae from the spinal column. Spondylolysis is the cause for frequent low back pain in children. It is more common among children and teenagers who participate actively in sports such as football, weightlifting and gymnastics.

Causes

Spondylolysis occurs as a result of a defect or stress fracture in the pars interarticularis, the part of the lumbar spine joining the upper and lower joints. Genetic factors may have a role. Children born with thin vertebra are prone to vertebral stress fractures. Also, repetitive trauma to the lower back area that occurs during sports and other activities can cause weakness of the pars interarticularis, resulting in spondylolysis.

Symptoms

Although initially the patient may not have any symptoms, lower back pain is apparent during the teenage growth spurt period. The pain worsens with vigorous physical activities and exercises. At times, the pain may feel similar to a muscle strain.

Risk Factors

Risk factors for developing spondylolysis include:

  • Family history of back problems
  • Repetitive trauma to the lower back
  • Increased lordosis (swayback)
  • Incomplete development of spinal cord (spina bifida occulta) and
  • Participation in sports such as football, gymnastics and weight lifting that require constant overstretching of spine

Diagnosis

Your surgeon diagnoses spondylolysis by asking several questions and performing several tests that includes:

  • Family History
  • Medical History
  • Physical Examination
  • X-ray
  • MRI scan
  • SPECT scan (single photon emission computed tomography), sometimes also with a CT scan

Treatment

Primary treatment for spondylolysis is always conservative. The goal of the conservative treatment is to reduce the pain, allow the fracture to heal (if it is only a stress reaction) and improve the function. Once a lysis or a complete break has occurred these do not heal and the goal of treatment is to relieve the symptoms of back pain.

Conservative treatment options include:

  • Rest : Adequate rest should be taken and strenuous exercises should be avoided until the symptoms subside
  • Medications : Nonsteroidal anti-inflammatory drugs (NSAID’s) or other pain medicines may be prescribed to reduce the pain and inflammation.
  • Physical therapy : An exercise program helps to strengthen the abdominal and back muscles, improve flexibility and increase range of motion of the lower back
  • Use of braces : In severe cases of spondylolysis, a brace or back support may be used to stabilize the lower back during healing

Surgical treatment

Surgery is sometimes required if spondylolysis progresses into spondylolisthesis. The goal of the surgery is to remove any abnormal bone compressing a nerve and to stabilize the spine.

Decompressive Laminectomy & Spinal Fusion

In this procedure a portion of the bone or lamina imparting pressure on the nerves is removed. An incision is made in the back, then part of the bone and thickened tissue pressing on the spinal nerves is removed. This allows more space for the nerves thus relieving pain and pressure. This procedure makes the spine unstable and therefore spinal fusion will be performed to stabilize the spine.

Spinal fusion is the procedure of joining two adjacent vertebrae. During the procedure a piece of bone, taken from elsewhere in the body or donated from a bone bank, is transplanted between the adjacent vertebrae. As healing occurs, the transplanted bone fuses with the spine. This stimulates growth of a solid mass of bone which helps to stabilize the spine. Metal implants including rods, screws, and/or cages are used to hold the vertebra stable until the new bone grows between them.

Pars repair

Occasionally if spondylolisthesis is not present and the level of the pars fracture is at L4 or above, a pars repair can be performed to try to get the fracture itself to heal without doing a spinal fusion. This involved placing metal screws, rods, hooks, and/or cages to stabilize the fracture and using bone graft products to allow the fracture to heal.

Prevention

Although spondylolysis is not completely preventable, certain factors can reduce the risk of developing the condition:

  • Maintaining a healthy weight to reduce stress on the lower back
  • Core exercises to keep the abdominal and back muscles strong will help to support the lower back
  • Eating a well-balanced diet to keep your bones strong