Posterior Lumbar Spinal Fusion
Posterior Lumbar Inter-body Fusion - P.L.I.F.
Trans-foraminal Lumbar Inter-body Fusion - T.L.I.F.
Who Needs It?
A posterior fusion is performed on the lumbar spine when there is evidence if pain due to the spinal discs or joints themselves and/or abnormal movement of the bones. The technique also allows the surgeon to decompress the nerves in the spine at the same time as performing the fusion operation.
The Operation
This is performed under general anaesthesia with the patient lying face down on a specially padded mattress. The incision is in the line of the spine over the affected disc or discs, and the spine is approached between the muscles. Some bone may be removed from the back of the spine to allow access to the disc space and decompress the nerve roots.
The surgeon may use metal (titanium) screws and bone graft to stabilise the spine and allow the bones to heal - the fusion. If an inter-body fusion is to be undertaken, material (usually a cage containing bone graft or bone substitute) is inserted into the disc space from behind. This has the effect of adding additional support to the disc space and allows a larger surface area for the fusion to occur across.
Recovery
Most patients are out of bed the day after the operation and out of hospital a few days later. The surgeon may prescribe a brace (a moulded corset) to be worn when mobile for six to twelve weeks post-operatively. It may take between three and six months for the bones to fuse, although many patients are fused before this time.
Patients may return to work in a sedentary occupation when they feel comfortable. Those in manual jobs may need to be off work for longer, until the fusion is solid, as demonstrated by the x-rays.
Follow-Up
Patients are seen at six weeks post-operatively and then at 3, 6 and 12 months with x-rays taken at each visit to determine the stage of healing. If metal screws are used these may be removed 1 - 2 years later, but this is usually not required.
What are the risks of this operation?
| Risk | Cause |
% Risk (note figures vary) |
| Nerve injury | Damage to the nerve whilst removing disc/bone or inserting screws | <1 (some papers say up to 25%) |
| Fluid leak | Small tear in the nerve sheath allowing leakage of cerebrospinal fluid | <1-5 (But approx higher if previous surgery |
| Infection | Contamination during surgery or, rarely, late infection via the blood | Approx 1 |
| Failure of fusion | If the bone graft does not heal, the pain may return | Up to 30%, depending on technique used |
| Adjacent disc damage | The stiffening effect of the fusion puts more pressure on the disc above (or below) | 4 - 12% (some papers say higher) |
| Wound pain | Surgery | All to some extent |