PLF (postero-lateral fusion)
This technique can be done either with or without instrumentation (metal work). In fusion without metal work (non-instrumented fusion) only a bone graft is required, which is placed at the back and sides of the vertebra. Patients will usually need to wear a brace for a few months afterwards. With the technical advance of implants, only few spinal surgeons still perform this technique. In instrumented fusion (pedicle screw fixation) screws are inserted through the pedicle into the vertebral body (see ‘The Normal Structure of the Spine’). These are connected with rods.
PLIF (posterior lumbar interbody fusion)
Through a midline incision the disc between two vertebrae is removed and the nerves decompressed. A cage is inserted as a spacer into the disc space. Screws are place in the pedicles of the vertebra and connected with rods (as in pedicle screw fixation – above). A bone graft is placed into and around the cage and sides of the spine.
TLIF (transforaminal lumbar interbody fusion)
Similar to PLIF. One facet joint (a small joint connection to adjacent vertebra) is resected to allow access to the disc space. This procedure is usually less traumatic for the muscles.
ALIF (anterior lumbar interbody fusion)
The spine is fused through an incision in the abdomen which allows access to the front of the spine. A simple cage is not indicated and will require additional support from the front (plate) or through a additional procedure from the back (pedicle screw fixation). The main advantage of this technique is that the back muscles will not be affected. However, the large vessels in front of the spine and other pelvic organs are at risk.
XLIF (extreme lateral interbody fusion)
The spine is fused through an incision at the side of the abdomen (flank). As for ALIF a simple cage is not indicated and will require additional support from the side with a plate or more commonly through a additional procedure from the back (pedicle screw fixation) which can be done minimal-invasive.
Depending on the underlying condition. Up to 30% of patients undergoing a lumbar fusion for lower back pain in the absence of instability will have minimal or no improvement of the pain. This should be borne in mind when considering surgery for back pain.
Depending on the underlying condition. The back will feel sore for a few weeks. It is important to know that it will take at least 3-4 months for the bone to fuse and therefore pre-existing pain might take a while to improve.
Commonly asked questions
Are some techniques better than others?
All of these fusion techniques have advantages and disadvantages. Which technique is used for a specific case depends on the underlying problem and surgeon’s preference.