Spondylolisthesis is a type of spinal deformity where one vertebra is displaced over the one below it.

The displacement, if forward, is called anterolisthesis and if backward, is called retrolisthesis. This problem generally occurs in the lower back or lumbar spine between the last two lumbar vertebrae (L4 – L5) or between the last lumbar and first sacral vertebra(L5-S1). Spondylolisthesis is responsible for causing narrowing of the spinal canal or compression of the nerves exiting at that level.

Types of Spondylolisthesis

There are five types of spondylolisthesis as listed below. The risk of developing it increases if there is a family history of backache or in athletes like gymnasts, weight lifters and football linemen whose spines are subjected to large forces repeatedly.

• Dysplastic: This is a congenital condition in which there is a defect during the formation of the vertebra.
• Isthmic: This is the most common type in which the front portion of the vertebra gets separated from the back portion. This is often seen in sportsmen who tend to over-extend the lower back like gymnasts and football linemen.
• Degenerative: This is common in elderly people because of osteoarthritis. The slippage may be forwards or backwards. The displacement is not severe and does not usually cause neurological problems.
• Pathological: It occurs due to a weakened bone for e.g. if there is a tumour.
• Traumatic: This is a very rare type due to a back injury.

Symptoms and Signs of Spondylolisthesis

• The most important symptom is pain in the lower back which gets worse after exercises, especially those which cause over-extension of the lower spine.
• There may be a decrease in the range of motion of the lower back and tightness of the hamstrings (calf muscles located behind).
• Neurological symptoms like pain, numbness, tingling and weakness in the legs due to nerve compression.
• In severe cases there may be loss of bladder or bowel control.

Diagnosis of Spondylolisthesis

The physician may suspect spondylolisthesis after taking the patient’s history and some examination. It can be confirmed by X-rays of the lumbar spine in the lateral view. The severity of the condition is described by grading it from 1to 5 where 1 is the mildest and 5 is the most severe.

Treatment of Spondylolisthesis

The treatment options are conservative and surgical. In mild and uncomplicated cases, rest is prescribed while athletes are advised to discontinue exercises for some time. Anti-inflammatory drugs are prescribed for backache and specific exercises help to strengthen the abdominal muscles. If a patient has symptoms of tingling, epidural steroid injections are of value. In athletes a special brace can be worn which extends the lumbar spine and promotes fusion of the two bones.

Surgery: Surgery depends on the grade of the condition and if the bone is active. In some cases a bone graft has to be placed , fitted with screws. If the nerves are compressed, decompression is carried out and the area around the nerves is cleared. The surgeon takes a call to join the vertebrae (lumbar fusion) in the original position or in the new position after the bone has slipped.

Prevention of Spondylolisthesis

Spondylolisthesis cannot be completely prevented. However, certain athletes like gymnasts and football linemen have a higher risk of developing it.