Fusion When Stability Is Needed
Understanding when and why spinal fusion is the best option
While motion preservation is ideal when possible, spinal fusion remains the gold standard for many conditions requiring stability. Modern minimally invasive fusion techniques offer excellent outcomes with less tissue disruption than traditional open surgery. This chapter explains when fusion is necessary and the advanced techniques Dr. Greenberg uses in Fort Wayne.
When Fusion Is the Right Choice
Spinal fusion permanently connects two or more vertebrae, eliminating motion at that segment. This is appropriate when:
Instability
Spondylolisthesis (vertebral slippage), fractures, or severe disc degeneration causing abnormal movement between vertebrae.
Deformity
Scoliosis, kyphosis, or other spinal curves causing pain, imbalance, or neurological symptoms.
Severe Arthritis
Advanced facet joint degeneration where motion preservation would not be effective or durable.
Multi-Level Disease
Extensive stenosis or disc disease affecting multiple levels, where decompression alone would create instability.
Revision Surgery
Prior surgery has altered anatomy or created instability requiring fusion for stability.
ACDF (Anterior Cervical Discectomy and Fusion)
Purpose: Remove damaged cervical disc and fuse vertebrae to treat arm pain, myelopathy, or instability when motion preservation is not appropriate.
The Procedure
- Small incision at front of neck (typically 1-2 inches)
- Remove damaged disc completely
- Decompress spinal cord and nerve roots
- Insert bone graft or cage to maintain disc height
- Secure with plate and screws for stability
- Fusion occurs over 3-6 months as bone grows
When ACDF Is Preferred Over Disc Replacement
- Significant facet joint arthritis
- Kyphotic (backward) deformity requiring correction
- Multi-level disease (3+ levels)
- Ossification of posterior longitudinal ligament (OPLL)
- Prior fusion at adjacent level
- Patient preference for proven long-term track record
Recovery and Outcomes
- Hospital stay: Overnight or 23-hour observation
- Collar: May be used for 4-6 weeks (varies by surgeon)
- Return to desk work: 2-4 weeks
- Fusion healing: 3-6 months
- Success rate: 85-95% experience significant symptom relief
- Fusion rate: Greater than 95% with modern techniques
Learn More: Read the complete ACDF procedure guide.
MIS TLIF/PLIF (Minimally Invasive Lumbar Fusion)
Purpose: Decompress nerves and stabilize the lumbar spine through small incisions, treating stenosis, spondylolisthesis, or instability.
TLIF vs. PLIF: What's the Difference?
- TLIF (Transforaminal): Approach from the side, through the foramen. Less nerve retraction, single-sided approach.
- PLIF (Posterior): Approach from directly behind. Allows bilateral cage placement.
- Both achieve: Complete decompression, interbody fusion, and stabilization
The MIS Technique
- Two small incisions (1-2 inches each) on the back
- Tubular retractors dilate muscles without cutting
- Remove lamina and decompress nerves
- Remove damaged disc
- Insert bone graft cage between vertebrae
- Place pedicle screws and rods for stability
- Fusion occurs over 6-12 months
Advantages of MIS Fusion
- Less muscle damage: Muscles dilated, not stripped from bone
- Less blood loss: Smaller incisions, less tissue disruption
- Less post-operative pain: Reduced tissue trauma
- Shorter hospital stay: 1-2 nights vs. 3-5 for open surgery
- Faster recovery: Return to activity weeks sooner
- Same fusion rates: Equivalent outcomes to open surgery
Recovery Timeline
- Hospital stay: 1-2 nights
- Walking: Same day or next day
- Return to desk work: 4-6 weeks
- Return to physical work: 3-6 months
- Fusion healing: 6-12 months
- Full recovery: 12-18 months
Learn More: Explore the detailed MIS TLIF/PLIF guide.
Robotic-Assisted Spinal Fusion
Purpose: Use robotic guidance to place pedicle screws with submillimeter accuracy, enhancing safety and precision in complex cases.
How Robotic Guidance Works
- Pre-operative CT scan creates 3D model of spine
- Surgeon plans optimal screw trajectories
- Robotic arm holds instruments in precise position
- Real-time navigation confirms accuracy
- Surgeon maintains full control throughout procedure
Benefits of Robotic Assistance
- Enhanced accuracy: Submillimeter precision in screw placement
- Improved safety: Reduced risk of nerve or vessel injury
- Better outcomes: Optimal screw positioning improves fusion rates
- Less radiation: Reduced fluoroscopy time during surgery
- Handles complexity: Especially valuable in revision surgery or deformity
When Robotic Guidance Is Most Valuable
- Complex deformity correction
- Revision surgery with altered anatomy
- Multi-level fusions
- Challenging anatomy (small pedicles, scoliosis)
- Minimally invasive approaches with limited visualization
Important: The robot doesn't perform surgery—it's a guidance tool. The surgeon's skill, judgment, and experience remain the most critical factors in surgical success.
Learn More: Read about robotic-assisted fusion and separating myths from evidence.
SI Joint Fusion
Purpose: Stabilize the sacroiliac joint to relieve chronic lower back and buttock pain when conservative treatments have failed.
The Procedure
- Small incision at the side of the buttock (1-2 inches)
- Minimally invasive approach to SI joint
- Insert 2-3 titanium implants across the joint
- Implants provide immediate stability
- Bone grows around implants over 6-12 months
Who Needs SI Joint Fusion?
SI fusion is considered after:
- 6+ months of conservative treatment (therapy, injections, medications)
- Positive diagnostic injection confirming SI joint as pain source
- Significant quality of life impact
- No other treatable pain sources identified
Recovery and Outcomes
- Hospital stay: Same-day or overnight
- Weight-bearing: Immediate, with walker or crutches initially
- Return to desk work: 2-4 weeks
- Return to full activity: 3-6 months
- Success rate: 70-80% experience significant pain relief
Learn More: Read the complete SI joint fusion guide.
Revision Spine Surgery
Revision surgery is more complex than primary surgery and requires specialized expertise. Dr. Greenberg's fellowship training and experience make him well-suited to evaluate and treat complex revision cases.
Common Reasons for Revision
- Pseudarthrosis: Fusion failed to heal properly
- Adjacent segment disease: Degeneration at levels above or below prior fusion
- Recurrent herniation: New disc herniation at same or different level
- Hardware complications: Screw loosening, breakage, or malposition
- Persistent stenosis: Incomplete decompression from prior surgery
- Infection: Requires hardware removal and treatment
The Revision Approach
Successful revision surgery requires:
- Thorough review of prior surgery records and imaging
- Accurate identification of pain source
- Realistic expectations about outcomes
- Careful surgical planning to address specific problem
- Often longer recovery than primary surgery
Learn More: Explore the detailed revision surgery guide.
Key Takeaways
- Fusion is necessary when instability, deformity, severe arthritis, or multi-level disease is present.
- Minimally invasive fusion offers the same outcomes as open surgery with less tissue damage and faster recovery.
- Robotic guidance enhances accuracy and safety, especially in complex cases.
- SI joint fusion can provide relief when conservative treatments fail for SI joint dysfunction.
- Revision surgery requires specialized expertise and careful evaluation to identify the cause of persistent symptoms.
Medical Disclaimer: This chapter provides educational information only and is not intended as personal medical advice. Every patient's condition is unique. Consult with Dr. Greenberg or another qualified spine specialist for an accurate diagnosis and personalized treatment plan.