Lumbar total disc replacement
Overview of surgery
In younger individuals (below 60 years) a painful and degenerated disc from the lower back can be removed and replaced with an artificial disc. The artificial disc (made of metal and lined with plastic) retains movement at the operated level of the spine. As opposed to spinal fusion which stops movement at the involved region of the spine. Retention of spinal movement also has the advantage of reducing the stresses on the adjacent intervertebral discs
Steps of the surgery:
- The surgery is performed under general anaesthesia, with the patient lying on the back
- The spine is accessed through an incision on the skin over the lower abdomen. The spine is exposed by moving the intestines and large blood vessels aside. The involved disc(s) is completely removed and the resultant space is filled with an artificial disc made of cobalt-chromium and having a plastic liner
- The incision (cut) is closed with dissolvable sutures. A drain tube will remove the blood that collects at the surgical site. A urinary tube may be used to drain the bladder.
The Success rates and the outcomes
This surgery is used to treat a very difficult problem- chronic low back pain resulting from disc degeneration. Although the results are not uniform, around 70-75% of patients have relief of symptoms after surgery and are able to function better. However, this procedure is indicated in a few carefully selected patients only.
Your pathway to recovery:
- Following surgery, the patient will be moved to the recovery room. Adequate pain relief and intravenous fluids will be provided. When the patient is comfortable, he/she will be transferred to a high dependency ward for an overnight stay or moved back to the ward
- Most patients will be encouraged to walk the day after surgery with or without a back brace. Normal diet or a soft diet is usually advised after 24-36 hours
- The duration of stay in the hospital may extend from 3-6 days depending on comfort and ability to walk and the surgeon will decide on the date of discharge.
Allergic reactions to medications and conditions like pneumonia, stroke or heart attack, though rare and not directly caused by the surgical treatment, may have serious consequences.
Surgical complications can include bleeding, infection, spinal fluid leak, injury to the veins and arteries near the spine, injury to the spinal cord and nerves and its surrounding protective layer (dura). Injury to the spinal cord or the nerves during surgery can result in varying degrees of muscular paralysis, alteration of normal sensations and loss of bowel and bladder control which may be permanent or may recover over a period of time. An injury to the covering layers of the nerves (dura) can result in a leak of spinal fluid and may rarely require a repeat surgery. Damage to the large blood vessels (1-10%) in front of the spine may result in excessive blood loss. The bone graft may not heal and fuse the spine (non-union) and may in some instances require further surgery.
A unique risk of an anterior lumbar surgery in males (especially while approaching the L5-S1 region) is damage to the nerves in front of the spine that can result in retrograde ejaculation (instead of the semen being ejaculated out of the body, it enters the urinary bladder). Retrograde ejaculation can make conception very difficult. Fortunately the risk is less than 1%. Anterior lumbar surgery does not usually cause impotence.
A 1-5% incidence of post-operative wound infection is possible despite antibiotics given before and after surgery. Superficial infections can be treated with antibiotics, while deep infections may require a wound wash-out under anaesthesia. The presence of an infection in any other region (urinary bladder, chest and skin) immediately prior to surgery, increases the risk of post-operative infection, so inform your surgeon about this.
Deep vein thrombosis (DVT – clotting of blood in your calf muscles) and pulmonary embolism (clot migrating to your lungs) are uncommon after an elective spine surgery, particularly when you are out of bed and walking within 24 hours after surgery. We do not routinely use medications to prevent DVT; however, if you have had an episode of DVT in the past, let your surgeon know.