The vertebral bodies are like links in a chain. Joints and spinal discs connect them to each other. When this order is disturbed, the vertebral body can move against each other. This is known as spondylolisthesis medically speaking.
Due to spondylolisthesis, the spine loses its stability which leads to severe back pain. At the same time, the nerve roots in the spinal canal are squeezed due to the shifted vertebral bodies resulting in leg or arm pain.
The causes of spondylolisthesis are diverse and can only be differentiated through an X-ray. In younger people, the cause of spondylolisthesis can be a fracture of the vertebral arch due to overexertion, or more uncommonly a congenital anomaly of the closure of the spinal arch. This is known as genuine spondylolisthesis.
After the age of 40, pseudospondylolisthesis may develop. The joints with their associated ligamentous structures are relaxed and the spinal discs are worn down and thin. Then, the instable segment slides away. This condition is graded into four degrees of severity.
In order to avoid a further slide and to restore the harmonious alignment of the spine, a stabilising operation is mostly required with the insertion of titanium implants.