Spondylolysis and Spondylolisthesis
What are Spondylolysis and Spondylolisthesis?
Spondylos - vertebra; lysis - break; listhesis - slip.
Spondylolysis refers to a break in the pars interarticularis (see picture) which constitutes a hook and claw mechanism that prevents the vertebrae from slipping forward on the one below. Spondylolisthesis refers to a condition where a vertebrae slips forward to varying extents on the one below.
What causes these diseases?
Spondylolysis is seen in approximately 6% of the population. It is seen more frequently in gymnasts and cricket bowlers. Spondylolysis can occasionally lead to spondylolisthesis.
Spondylolisthesis is caused by numerous factors that disturb the integrity of the hook-claw mechanism located behind the vertebral body. Spondylolysis, fractures and abnormal shaped hook-claw mechanism (dysplastic) can lead to a slip of the vertebra on the one below - spondylolisthesis.
What are the symptoms/effects?
Spondylolysis and spondylolisthesis may or may not cause symptoms. The symptoms caused may include back pain, leg pain, muscular weakness and numbness in the lower limbs. Spondylolisthesis may progress (increased slippage) during the adolescent years.
How are they diagnosed?
Spondylolysis and spondylolisthesis is diagnosed by a thorough history and clinical examination and confirmed with x-rays, CT scan and MRI scan. The MRI scans reveals the extent of neural compression and the integrity of the intervertebral discs whereas the CT scan provides better visualisation of the bony anatomy including the spondylolysis.
What are the treatment options?
Treatment is not warranted in the absence of symptoms. A trial of non-operated treatment is advisable as a first stage of treatment. Non-operative treatment includes short duration of pain medications, physiotherapy, muscle strengthening exercises. Surgery is indicated when the a) failure of symptoms to subside after non-operative treatment, b) significant weakness in the legs and feet at presentation and c) involvement of the bladder with difficulty in passing urine d) progressive slippage (spondylolisthesis). Surgery may be in the form of a decompression (removing compression from the nerves) with or without a fusion.