Lumbar arthroplasty or disc replacement involves replacing a diseased disc segment with a prosthetic joint. This has the advantage of allowing motion in the lumbar spine to be maintained.

Indications

Lumbar arthroplasty is considered for axial back pain secondary to discogenic disc disease, when there is a discrete level involved as evidenced by typical changes on a MRI scan.

Diagnosis

The diagnosis is made with history, physical examination and corroborated with focused X-ray and MRI examination.

Non -Operative Treatment

This involves rest, activity modification, pain-killers, physical therapy and occasionally corticosteroid and local anaesthetic injections.

Risks

Specific risks include: transient postoperative slowing of bowel movement (ileus), vascular injuries (as the vessels lie immediately adjacent to the lower lumbar vertebrae) and in males retrograde ejaculation (incidence of roughly 5% in the medical literature). Other risks include subsidence of the implant and rarely implant migration.

Operative Technique

The disc space can be approached through a number of corridors. Dr Nair utilises the retroperitoneal (gains access to the disc space behind the bowel) approach and undertakes the operation in conjunction with a vascular surgeon.

The diseased disc is then excised and the artificial disc inserted. Initial stability is achieved by screws, blades or an interference fit and ultimately the implant bonds with the adjacent vertebral body.