From the Guidelines
Vertebral fusion surgery is indicated for patients with spinal instability, progressive deformity, or intractable pain that has not responded to conservative management, as recommended by the most recent and highest quality study 1. The indications for vertebral fusions include:
- Severe degenerative disc disease
- Spondylolisthesis (especially grades 3-4)
- Spinal fractures with instability
- Spinal tumors causing structural compromise
- Severe scoliosis (typically curves >45-50 degrees)
- Recurrent disc herniation
- Failed previous spine surgery with continued symptoms Fusion may also be warranted for spinal infections causing destruction, symptomatic pseudarthrosis, or as an adjunct to decompression procedures when significant instability is anticipated, as suggested by 1. The decision for fusion should follow a thorough clinical evaluation including physical examination, appropriate imaging (MRI, CT, X-rays), and failure of conservative measures such as physical therapy, medication management (NSAIDs, muscle relaxants, gabapentinoids), and interventional procedures (epidural injections) for at least 3-6 months, as recommended by 1. Patient factors including age, comorbidities, bone quality, smoking status, and activity goals should be carefully considered before proceeding with this definitive but potentially limiting intervention, as noted in 1 and 1. The benefits of stabilizing painful motion segments must be weighed against the risks of adjacent segment disease, pseudarthrosis, hardware complications, and the significant recovery period of 6-12 months, as discussed in 1.
From the Research
Indications for Vertebral Fusions
The indications for vertebral fusions include:
- Degenerative disc disease, particularly when associated with chronic low-back pain, spinal instability, or severe degenerative changes 2, 3
- Lumbar herniated disc with evidence of spinal instability, chronic low-back pain, and/or severe degenerative changes, or if the patient participates in heavy manual labor 4
- Recurrent disc herniations with evidence of instability or chronic low-back pain 4
- Lumbar spinal stenosis with underlying biomechanically unstable spine, failed back surgery syndrome, degenerative instability, considerable essential deformity, symptomatic spondylolysis, refractory degenerative disc disease, and adjacent segment disease 5
- Extensive decompression associated with a wide disc space or insufficient bone stock 5
Surgical Techniques and Outcomes
Different surgical techniques for vertebral fusions have been compared, including:
- Noninstrumented posterolateral fusion (PLF)
- Instrumented posterolateral fusion (IPLF)
- Interbody fusion (IBF) Studies have shown that while all techniques can improve patient-reported outcomes, the addition of interbody fusion to posterolateral fusion may be associated with a higher risk for additional surgery 6