Spondylolisthesis is an instability of the spine and is also known as spondylolisthesis because one vertebra tends to slide over the next deeper one.
Most often the vertebrae L5 and L4 are affected, only in rare cases the overlying section. In spondylolisthesis, the vertebrae usually slide forward (anterolisthesis), only rarely backwards (retrolisthesis) or to the side.
About 5% of the population is affected by this back problem.
Forms of spondylolisthesis
A distinction is made between gravity states: I° to V° severity; the I° degree corresponds to an offset of the vertebral bodies to each other by less than 25% of the vertebral body depth.
The other degrees of severity increase progressively up to the V° degree, at which the vertebrae have lost contact with each other and the upper one slips completely and positions itself in front of the lower vertebra; this is referred to as spondyloptosis.
In this condition, the back is usually inflamed and painful.
There are two types of spondylolisthesis: the wear-related, degenerative form and the true form of spondylolisthesis due to cleft formation (spondylolysis).
Degenerative spondylolisthesis is usually caused by osteoarthritis, which leads to loss of contact of the vertebral joints; normally the second severity is not exceeded and it mainly affects women and over 50-year-olds.
It can also arise as a complication as a result of surgery or be caused by infections and tumors (neoplasms).
The situation is aggravated if there is degeneration of the longitudinal ligaments and facet joints, and the capsule-ligament structures are damaged.
Degenerative spondylolisthesis is characterized by a narrowed spinal canal and a disorder of the nerve roots.
Spondylolysis is the interruption (splitting) of the bony connection between the adjacent vertebral bodies (the area between the upper and lower articular process and spinous process: interarticular portion).
Spondylolysis can lead to the development of spondylolisthesis.
Cleft formation occurs slowly in hereditary patients at the age of 6 years and continues to develop during the growth phase; once growth is complete, it stabilizes and does not change further in adulthood.
The lesion can also occur as a result of repeated microtrauma (stress or fatigue fracture), when the interarticular portion between the joints of the vertebral arch is weak and unconsolidated. Over time, the affected vertebral body and the articular and transverse processes tend to slide forward over the next deeper vertebra (spondylolisthesis).
In some cases, a repair process is set in motion that restores this bony connection, but the vertebra then appears lengthened and shifted forward and it is possible that only one side closes.
What are the symptoms of spondylolysis?
People suffering from spondylolisthesis can be completely painless and during an X-ray examination, a spondylolisthesis is accidentally detected; under certain circumstances, low back pain has become noticeable from time to time in the past.
Adults suffer from low back pain more often than children.
In more severe cases, the pain can also radiate to the hip and thigh, as in lumboischialgia or lumbocruralgia.
As a rule, the pain is not excessively strong and affects the area where the vertebra is displaced.
When stretching, the pain increases, when bending it subsides. Only rarely is there a herniated disc between the two vertebrae affected by the spondylolisthesis, but often in the area above. Magnetic resonance of L5 with gap formation in the posterior vortex area.
How is spondylolysis diagnosed?
For diagnosis, a lateral X-ray of the lumbar cross section of the spine is taken; here you can see the severity of the spondylolisthesis, the height of the underlying intervertebral disc and any damage to the interarticular portion.
The function recordings are made at maximum diffraction and maximum extension; If the listhesis increases when bending forward and becomes less when stretching backwards, this is proof of the instability of the vertebra.
Magnetic resonance indicates possible compression of the nerves, especially those located under the displaced vertebra. The intervertebral disc of an adult can show severe signs of wear, limiting the space available to the nerve roots.
The functionality of the nerves originating from the vertebra affected by spondylolisthesis can be examined with the help of electromyography, which indicates nerve conduction and suffering of the nerve root.
Which therapy is suitable?
Treatment can be conservative or surgical.
Conservative therapy is preferable here, because in this way intervention can be avoided; very good results can be achieved with slight spondylolisthesis.
Physiotherapy to strengthen the abdominal and back muscles improves the stability of the lumbar spine. If the pain does not subside, experts recommend ultrasound or Tecar® therapy to relieve the inflammation.
Rigid corsets, which immobilize part of the spine and reduce hyperlordosis (strong curvature of the spine forward), are no longer prescribed to patients today.
Over time, the intervertebral disc, which lies under the sliding vertebra, can degenerate, become thinner and eventually disappear altogether. In this way, the two vertebrae approach each other until they unite and grow together (ossification).
If the pain is chronic and very severe, surgical joint fusion (arthrodesis) can be performed, i.e. stabilization of the vertebrae by means of synthetic agents that connect the vertebrae with each other.