Lumbar fusion is a surgery employed for the union of one or more lumbar vertebra. In all spinal fusions a bone graft is used to promote healing of the fusion. Generally, the graft material is placed between the adjacent vertebrae, which are to be fused. During the healing process, the bone graft fuses with the vertebrae and stimulates the growth of a solid bone mass which stabilizes the spine.
Traditionally, bone graft was harvested from the patient's own body. Today, a variety of artificial bone grafts are available to reduce the need for harvesting the patient's own bone. Surgical instrumentation (screws and plates) are implanted into the spinal bones to stabilize the fusion during the healing process.
Lumbar fusion is indicated for chronic low back pain, lumbar instability, and deformity (abnormal spinal curves). In patients with severe leg pain, a significant amount of bone compressing the nerves is also removed. This increases the space surrounding the nerves, relieving pain, but this also makes the spine unstable; therefore, a spinal fusion is performed to stabilize the spine.
Before the procedure, the patient is anesthetized and sedated. The positioning of the patient depends on the type of interbody fusion to be performed. The skin over the area is cleansed and prepared. The procedure is performed under fluoroscopic X-ray guidance.
There are different approaches to lumbar fusion surgery which include:
- Posterior Lumbar Interbody Fusion, Anterior Lumbar Interbody Fusion or Transforaminal Lumbar Interbody Fusion: The spine is approached either from the back (Posterior Lumbar Interbody Fusion [PLIF]), the front (Anterior Lumbar Interbody Fusion [ALIF]) or the side (Transforaminal Lumbar Interbody
- Direct Lateral Interbody Fusion (DLIF) and Extreme Lateral Interbody Fusion (XLIF): the spine is approached from the side (lateral) rather than from the front or the back
- An AXIALIF (Axial Lumbar Interbody Fusion): the lower discs of the spine near the tailbone are accessed through an opening behind the bottom of the spine
- 360-degree spine fusion: Both ALIF and PLIF are performed in the same procedure
- Posterolateral Fusion –the bone graft is placed along the back and sides of the vertebrae to stimulate bone growth
Screws and rods are used to hold the vertebrae together during the healing process.
Usually patients are discharged home within four to six days after the surgery. You may be advised to wear a back brace. Activities such as bending, twisting or lifting should be avoided to allow healthy healing of the fusion. Some patients may experience back pain and spasms after the surgery, but this usually resolves within a few days.
Possible complications after lumbar fusion surgery may include:
- Spine infection
- Damage to the spinal nerves
- Loss of sensation
- Bowel or bladder control problems
- Movement of the implant in the spine
- Pseudarthrosis, a painful condition due to inadequate healing of the bone effusion with the development of a false joint at the site
- Formation of blood clot in the legs
- Pain at the site of bone graft