There are three basic types of back surgery
1. A laminectomy – removing the back part of the bone (called the lamina) over the spinal column. A laminectomy is performed to relieve nerve root compression (pinched nerve) on one or more nerve roots in the spinal column. The compressed nerve root often causes back and leg pain. A segment of the entire lamina can be removed to relieve pressure on a nerve..
2. A discectomy – removing a portion of a disc to relieve pressure on a nerve.
3. A spinal fusion – this involves the permanent fusion of two or more vertebrae for more stability, to correct a deformity or to relieve pain. The surgeon will harvest small pieces of bone from your hip or pelvic bone and place them between the vertebrae. In many cases they will use wires, rods, screws, metal cages or plates to provide immediate stability.
How is a laminectomy performed?
Step 1: A laminectomy is performed with the patient lying on his stomach or side and under general anaesthesia. The surgeon (an orthopaedic or neurosurgeon) reaches the spinal column through a small incision in the back.
Step 2: He will use a retractor to spread the muscles of the back apart in order to expose the bony lamina.
Step 3: He cuts away part of the lamina to uncover the ligamentum flavum – a ligament supporting the spinal column.
Step 4: In the next step he will cut an opening in the ligamentum flavum to reach the delicate spinal canal containing the compressed nerve.
Step 5: The compressed nerve can now be seen as well as the bundle of nerve fibres (known as the cauda equina) to which it is attached. It is now possible to identify the cause of compression: a bulging, ruptured or herniated disc, or perhaps a bone spur.
Step 6: The source of the pressure can now be removed. This may involve removing the bulging portion of the disc or the bony spurs and scar tissue. The herniated disc is removed after the compressed nerve has been gently retracted to one side. The surgeon will remove as much of the disc as is necessary to take pressure off the nerve. Sometimes a fragment of disc has moved and presses on the nerve root as it leaves the spinal canal. This will often cause more severe symptoms.
Step 7: With the cause of compression removed, the nerve can now begin to heal. The space created by removal of the disc will gradually fill with connective tissue. The incision is closed in several layers, from the inside outwards.
Step 8: The skin layer will be closed with steri-strips, sutures or skin clips. A dressing will be placed over the incision to protect the wound.
This operation is normally performed within one or two hours, depending on the number of levels that are decompressed.
A plastic drain will run from inside the wound to remove any accumulating blood. In most cases, the drain can be removed on the second day after surgery.
An intravenous line to administer medication may remain connected through a vein in your hand or arm for two to three days.
Pain can and should be well controlled. Usually the acute pain subsides after a day or two. Pain may be most severe in the lower back. Leg pain may be caused by swelling of the previously compressed nerve and the trauma of the surgery. Muscle spasms across the back and down the legs are not uncommon and this can be relieved by muscle relaxants.
A physiotherapist will help you to begin standing and walking again, and show you how to get in and out of bed and how to sit, stand, and sleep.
What about new and less invasive procedures?
The era of less invasive surgery has dawned – also in back surgery. Smaller keyhole incisions are replacing large surgical cuts. These less invasive techniques include:
- Endoscopic discectomy – this technique employs a disposable scope that the surgeon inserts through a small incision. The protruded disc that is compressing the nerve is then removed using specially designed instruments.
- Vertebroplasty – the injection of bone cement into a fractured vertebrae. The hardened cement will seal and stabilise the fracture and relieve pain. People suffering from severe pain because of a compression fracture will be considered for this procedure, especially if they have difficulty standing and walking.
- Kyphoplasty – the insertion of a “balloon” to expand a compressed vertebra and the injection of bone cement.
Reviewed by Dr Pradeep Makan, orthopaedic surgeon, Melomed Gatesville and Life Vincent Pallotti Hospital in Cape Town and part-time lecturer in the department of orthopaedic surgery at the University of Cape Town, 2010.