Vertebral arthrodesis surgery is designed to stop movement in a painful vertebral segment, which in turn should decrease pain generated from the joint.
There are many approaches to lumbar arthrodesis surgery, and they all involve the following process:
Add a bone graft to a segment of the spine.
Set up a biological response that causes the bone graft to grow between the two vertebral elements to create a bone fusion.
Bone fusion, which consists of a fixed bone that replaces a mobile joint, stops movement in that joint segment.
How Vertebral Arthrodesis Works
At each level of the spine there is an intervertebral space in the anterior part and a pair of facet joints in the posterior part. These structures work together, define a segment of movement, and allow various degrees of movement.
Two vertebral segments must be fused to stop movement in one segment, so an L4-L5 vertebral arthrodesis (lumbar segment 4 and lumbar segment 5) is actually a single-level fusion. An L4-L5, L5-S1 arthrodesis is a 2-level fusion.
Types of vertebral arthrodesis
Instrumented posterolateral arthrodesis: The procedure is performed through the back.
Posterior lumbar interbody fusion (PLIF) arthrodesis: the procedure is performed from the posterior part and includes removing the disc between two vertebrae and inserting bone into the space created between the two vertebral bodies.
Anterior lumbar interbody fusion (ALIF) arthrodesis: the procedure is performed from the anterior part and includes removing the disc between two vertebrae and inserting bone into the space created between the two vertebral bodies.
For patients with the following conditions, if abnormal and excessive movement in a vertebral segment causes severe pain and inability to function, lumbar arthrodesis may be considered:
Degenerative lumbar disc disease.
Lumbar spondylolisthesis (isthmic, degenerative or postlaminectomy spondylolisthesis).
Other conditions that can be treated with spinal arthrodesis surgery are weakness or instability of the spine (caused by infections or tumors), fractures, scoliosis, or deformity.
Lumbar spine surgery is complex and subject to risks and complications, particularly in rescue surgery for failure of previous surgeries. Nerve injuries, cerebrospinal fluid leaks, infections, failure of the implanted material, failure of arthrodesis due to lack of integration of the graft and the consequent deterioration of the implanted osteosynthesis material can occur. This involves a refined technique and the good judgment of the surgeon to act at all times in accordance with the requirements of the patient's pathology.
It is important to note that with any type of vertebral arthrodesis there is a risk of clinical failure (meaning that the patient's pain does not go away) despite successful fusion.
Lumbar surgery well indicated and performed with the correct technique gives good results. The liberation of the affected roots and the resection of articular massifs constitute the basic elements to reach the healing of the low back pain, sciatica or lumbar claudication symptoms. Osteosynthesis material is incorporated to stabilize and immobilize the weakened vertebral segments and bone graft is added to make the assembly permanent. Regardless of the more or less prolonged surgical time, once the spine is released and stabilized, the patient can be incorporated and walk within the first 24 hours. The healing time of the process is considered to be 5-7 months, once the incorporation of the graft has been achieved and the remission of the clinic that motivated the surgery has been achieved.