Failed cervical spine surgery — “Why does my neck still hurt?”

Definition

Failed cervical (“neck”) surgery, analogous to failed back surgery, typically refers to persistent or worsening axial neck pain, radicular arm pain, cervical myelopathy, or new neurologic deficits after surgical intervention, in spite of technically adequate initial surgery. The incidence of dissatisfaction with the surgical result or persistence of symptoms after cervical surgery is thought to be in the range of 10-30%, varying with the type of surgery, the pathology, the severity of the pathology, and multiple patient factors. As another example, some surgical studies suggest a revision surgery rate of 4-15% within 5 years after an anterior cervical discectomy and fusion; at the Wascher Cervical Spine Institute, that number is less than 1%. WHY IS THERE SUCH A DIFFERENCE?

The key is identifying all factors responsible for your pain syndrome and treating each cause appropriately. Cervical surgery should generally be considered a last resort, only if all other causes can be ruled out, extensive conservative management has failed, symptoms are sufficiently severe, and the patient’s signs and symptoms correlate with the radiographic findings.

Common causes of failed cervical spine surgery

1. Incorrect Diagnosis: The most common cause overall. Noncervical causes of pain need to be ruled out BEFORE cervical spine surgery. These include rotator cuff and shoulder pathology; peripheral neuropathy; thoracic outlet syndrome; levator scapulae syndrome; myofascial pain; etc., all of which may be misdiagnosed as cervical disease.
2. Psychological Factors: depression and anxiety have been shown in multiple studies as influencing pain perception. Unrecognized psychiatric disease and issues resulting in secondary gain need to be resolved before cervical spine surgery can be reasonably offered. In some cases, formal depression screening and psychiatric intervention may be required.
3. Incomplete Nerve Root and/or Spinal Cord Decompression: Persistent nerve root compression or spinal cord compression after cervical surgery fails to solve the primary problem and leads to ongoing radicular symptoms or myelopathy. Foraminal stenosis (narrowing of the bone opening through which the cervical nerve must pass to exit the spinal canal) is the most common cause and is often underestimated pre-operatively.
4. Development of Adjacent Segment Disease: Arthritic degeneration above or below fused segments may be accelerated due to changes in mechanical relationships and physical stress caused by changes produced by the fusion. This can cause new or recurrent symptoms months to years after the initial surgery, resulting in radiculopathy or myelopathy. Adjacent segment disease is seen most commonly after extended, multilevel fusions.
5. Pseudarthrosis (Nonunion): If an attempted fusion fails to produce a solid, immobile result, micromotion at the operative level can, in some instances, result in instability (too much motion) and disabling pain. Risk factors include diabetes, osteoporosis, inflammatory conditions like rheumatoid or psoriatic arthritis, use of tobacco products, chronic use of steroidal and non steroidal anti-inflammatory agents, chronic renal insufficiency, etc.
6. Hardware Failure: Malpositioned or broken screws and plates, plate migration, or implant loosening can contribute to mechanical pain or pain caused by frank compression of the nerves and spinal cord. For example, it is imperative to preserve the vertebral body endplates during an anterior cervical fusion to minimize the risk of the interbody fusion device penetrating into the vertebral body above and below (variously referred to as “telescoping” or “impaction” or “settling”).
7. Failure to Achieve Adequate Alignment (Proper Sagittal Balance): Inadequate restoration of the normal cervical curvature (lordosis) or, worse yet, fusing the cervical spine in kyphosis can result in persistent neck pain and gravity-related muscle fatigue that is difficult to treat. Every effort must be made to not only decompress the affected nerve roots and spinal cord with surgery but also to recreate/maintain normal spinal architecture to avoid adjacent segment degeneration and further problems.
8. Infection: occult, low grade infection can lead to chronic osteomyelitis (bone infection); pseudarthrosis, hardware failure, progressive pain; and spinal deformity leading to recurrent nerve root and spinal cord compression. Even mild low-grade bacterial colonization with nonvirulent subspecies of bacteria can lead to chronic pain without systemic signs of infection.
9. Scar Formation: Exuberant scar formation (epidural fibrosis) can lead to recurrent compression of the spinal cord and nerve roots, resulting in recurrent symptoms. This has been shown to occur more commonly after cervical laminectomies when fusion is not performed.
10. Progression of Myelomalacia: When scarring has resulted within the spinal cord itself, even though adequate decompression has been accomplished by surgery, in certain instances the scar tissue can proliferate leading to burning pain, progressive weakness, numbness and tingling, etc. This so-called “dysesthetic neuropathic pain” can be exceedingly difficult to treat.

Evaluation of failed cervical surgery and associated diagnostic studies

1. Extensive Clinical History and Physical Examination: It becomes imperative to differentiate between pre-existing, persisting, recurrent, or new symptoms. All possible causes of the failed surgery need to be considered, with examination focusing on instability, signs of infection, or new findings of neurologic deterioration.
2. MRI of the Cervical Spine with and Without Contrast: will detect infection, recurrent compression and adjacent segment disease, progression of myelomalacia, and epidural fibrosis.
3. CT scan: best to evaluation bony integrity, presence or absence of a solid fusion, or hardware failure/loosening.
4. Dynamic Flexion-Extension Cervical Spine X-Rays: useful to identify instability, pseudoarthrosis, and loss of normal cervical lordosis.
5. Electrodiagnostic Testing: EMG/NCV testing can help differentiate true nerve root compression from peripheral nerve disorders and diseases mimicking radiculopathy.
6. Laboratory Blood Tests: ESR, C-reactive protein and CBC with differential can be used to look for inflammation if infection is considered.

Management strategies

1. Nonoperative Treatment: Management of failed cervical surgery begins with administration of NSAID’s, muscle relaxants, and neuromodulators like gabapentin and pregabalin. Physical therapy is also a mainstay to focus on stabilization and strengthening exercises. Epidural steroid injections or selective nerve root blocks with pain diaries, in selected cases, may be useful for both therapeutic and diagnostic purposes. Additionally, when indicated, psychological support for treatment of anxiety and depression is crucial to a successful outcome.
2. Surgical Revision: Indications for revision surgery would include persistent neurologic compression; mechanical instability and pseudarthrosis; hardware failure associated with chronic pain; progressive spinal deformity; symptomatic adjacent segment disease; and infection failing to respond to treatment. Options for surgical intervention include posterior cervical decompression, instrumentation, and fusion (PCDIF): extension of the previous anterior cervical fusion; combined anterior-posterior (360 degrees) procedures; and revision anterior cervical discectomy, instrumentation, and fusion (ACDIF) or anterior cervical corpectomy and fusion. Any revision surgery can be challenging, due to scar formation; higher risks of CSF leak and nerve root/spinal cord injury; higher risk of poor healing and infection; and lower success rates compared to primary surgery.

Prognosis

In general, outcomes after revision surgery are less predictable than primary surgery, depending on the procedure performed and its extent. Patients with demonstrable pain generators and mechanical problems (i.e., pseudarthrosis or new area of compression) have better outcomes than surgeries performed for axial neck pain alone.

Prevention of failed cervical surgery

Obviously, the goal of any surgeon is to prevent failed surgery. This can be achieved by:

1. Careful patient selection and detailed pre-operative assessment.
2. Exacting surgical technique that respects healthy tissues, with adequate decompression of neural elements and restoration of alignment (normal sagittal balance).
3. Pre-operative smoking cessation along with medical optimization, including bone health (correction of osteoporosis).
4. Setting realistic expectations regarding the goals and limitations of surgery.

Conclusions

Failed cervical surgery is a complex, multifactorial challenge that requires a comprehensive evaluation as well as personalized decision-making and management. Early recognition and treatment of modifiable risk factors, accurate diagnosis, and specifically-targeted interventions (nonoperative and operative) offer the best hope for optimal outcomes.

As cervical spine surgery evolves, better diagnostic tools, including AI-driven protocols for complex problems like failed spine surgery, along with ever-improving surgical techniques, will continue to reduce the incidence of surgical failure.

If you or a loved one has undergone a cervical surgery and is unhappy with the result, a second opinion is always a good idea, especially if additional surgery is considered. Call us today if we can be of assistance at 1-855-854-9274 — ask about our Free MRI Review.