What is the difference between these difficult terms relating to the low back/lumbar spine?
Spondylosis is arthritis of the spine. Here is a picture of this condition in the lumbar spine. Picture Tobi spine institute
Spondylolysis is a fracture of an area of the spine called the pars interarticularis. Here is an image of this.
Spondylolisthesis is a fracture of the pars interarticularis and a slippage of one vertebrae on the other. It can range from 25% to 100%. Here is an illustration of this condition.
Spondylolysis and Spondylolisthesis typically occur in athletes that are gymnasts or linemen in football where the low back is put into hyperextension with force. If a patient has these conditions lumbar extension or backwards bending is not supposed to be done because it can worsen the condition. If the slippage of the spine is too much an orthopedic spinal surgeon may need to stabilize the area with surgery. If a patient has numbness, weakness, or decreased reflexes in the legs the patient should is having pinching of the spinal nerves and this is a critical condition for the physician to look at more fully.