Pseudarthrosis After Cervical Fusion
If your cervical fusion did not heal, or your symptoms returned after an initially successful surgery, pseudarthrosis may be the reason.
Also Called: Failed fusion, non-union, painful non-union.
What It Is
Pseudarthrosis occurs when the bone graft from a prior neck fusion does not fully turn into solid bone. The treated segment stays slightly mobile instead of healing into one piece. That motion can keep the original pain, numbness, or weakness going, or bring it back after a period when the surgery seemed to work.
Causes & Risk Factors
Smoking is the biggest modifiable risk factor for a fusion failing to heal; it interferes with how bone forms. Risk also rises with the number of levels fused and with osteoporosis. Pseudarthrosis is more common than most patients realize, and it is easy to miss on standard imaging, especially early on.
Symptoms
- Persistent or returning neck pain after a prior cervical fusion
- Arm pain, numbness, or weakness that never fully went away — or that came back after initial improvement
- Imaging showing that the treated level hasn't fully healed
Diagnosis
A CT scan is the most reliable way to see whether the fusion has actually healed, since it shows bone in far more detail than an X-ray. Flexion-extension X-rays, taken bending forward and back, can also reveal motion at a level that shouldn't still be moving. A common pattern is symptoms that improved after the first surgery and then returned. The segment can start out stable enough to feel better, before that motion catches up with it again.
Treatment
Pseudarthrosis is a mechanical problem, the segment hasn't fused, so medication and therapy can ease symptoms but won't make the fusion heal on its own. Smoking cessation matters here specifically. It's the single biggest modifiable factor in whether a fusion unites. Surgery is considered when pain persists and imaging confirms the level hasn't healed.
Posterior Cervical Fusion
Stabilizing the level from behind is often the most direct way to complete a fusion that didn't heal from the front. It adds a second point of fixation without reopening the original approach.
Revision Spine Surgery
When more than one level is involved, or the case needs a broader look at what was done before, treatment follows from a full review of the prior surgery and current imaging.
Dr. Hirsch is board-certified and Yale-trained. Read his full background.