Am I a suitable candidate for cervical disc replacement rather than fusion (ACDF)?

Ideal candidates for cervical disc replacement have single or two-level degenerative disc disease with clear imaging-symptom correlation, adequate disc height (>3 mm), no severe endplate damage, preserved bone quality, and intact facet joints. Contraindications include prior fusion at the same level, significant instability, severe inflammatory arthropathy, active infection, and severe osteoporosis. A comprehensive evaluation including MRI and CT is required to determine suitability.

What is the difference between cervical disc replacement and ACDF fusion?

Cervical disc replacement removes the degenerated disc and implants an artificial prosthesis that permits 8–12° of preserved neck motion, while ACDF fusion eliminates movement at the treated level. Motion preservation matters because fusion increases stress at adjacent segments, accelerating degeneration. Studies show cervical disc replacement has a 6% adjacent segment reoperation rate versus 12–18% for ACDF at 10 years.

How long does cervical disc replacement surgery take and what is the hospital stay?

Single-level cervical disc replacement takes 1.5–2.5 hours; two-level procedures take 2–3.5 hours. Approximately 75–80% of patients are discharged within 24 hours of surgery. The anterior cervical approach requires only a small neck incision. A responsible adult must be present for discharge and provide transportation home.

Can I have an MRI after cervical disc replacement?

Yes. All TGA-approved cervical disc replacement devices used in Australia are MRI-compatible up to 3 Tesla, covering all standard clinical MRI machines. Some minor image artifact may occur around the implant area but rarely affects diagnosis at other levels. Always inform MRI staff about your implant before any scan.

Will I need a neck collar or brace after cervical disc replacement?

Modern cervical disc replacement does not require external immobilisation in most cases. A soft collar may be offered for comfort during weeks 1–2 if preferred, but is not mandatory. This contrasts with fusion surgery which typically requires 6–12 weeks of collar use. The absence of required immobilisation permits early neck motion and supports faster recovery.

What are the long-term success rates of cervical disc replacement?

Long-term studies show excellent outcomes. At 7–10 years, 85–92% of patients report good to excellent results. Clinical success (significant pain and neurological improvement) is achieved in 85–90% of patients. Patient satisfaction exceeds 90%. Motion preservation is maintained in 85–95% of implants at 10 years. Reoperation rates are significantly lower than after ACDF fusion.

Cervical Surgery Preoperative Assessment

Assessment Journey

The Preoperative Assessment JourneyWhy Assessment Matters

Preoperative assessment is not bureaucratic delay—it's surgical preparation. Every element of your assessment directly influences whether disc replacement is right for you, which approach works best, what risks apply, and how well you'll recover.

Rushed Assessment Leads To

Wrong surgical decisions
Increased complications
Suboptimal outcomes
Preventable revisions

Thorough Assessment Leads To

Confidence in decision-making
Optimised surgical planning
Reduced complications
Excellent long-term function

Assessment Timeline

4–8 weeks typical

Preoperative assessment journey visualisation showing 7 stages from consultation to surgery

Total timeline varies with complexity and optimisation needs

Your Assessment Ensures

Right decision for you

Best surgical approach

Your specific risks known

Sustained outcomes

Clinical Evaluation

Clinical Evaluation FrameworkUnderstanding Your Symptoms

The surgeon begins by understanding what is bothering you and why—not just accepting your self-reported diagnosis. A thorough cervical spine examination includes inspection, palpation, range of motion, neurological testing and specialised manoeuvres.

Chief Complaint & Symptom Characterisation

Neck only vs. arm radiation?

If arm pain, which fingers/hand region?

Constant vs. intermittent?

Positional triggers (what makes it better/worse)?

When did it start? Trauma or gradual onset?

Has it progressed, plateaued, improved?

Recent changes?

Is pain worse at certain times of day?

Numbness or tingling? Where?

Weakness in arms/hands?

Hand clumsiness or difficulty with fine motor tasks?

Walking problems or balance issues?

What activities are limited? (work, hobbies, ADLs)

Can you sleep through the night?

How much does pain affect your quality of life (0–10)?

What are your goals for surgery?

Physical therapy? How long? Response?

Medications tried? Which helped?

Injections or procedures? Outcome?

Surgery? When and where?

Why This Matters

• Localises problem: Specific dermatomal pattern suggests specific nerve root compression
• Suggests urgency: Myelopathy symptoms (hand clumsiness, gait disturbance) are urgent
• Assesses chronicity: Longstanding severe symptoms sometimes have worse outcomes
• Sets expectations: Realistic functional goals improve satisfaction

Physical Examination Protocol

Cervical spine physical examination showing dermatome testing regions

Motor Testing (Graded 0–5)

Shoulder shrugC5 (+ CN XI)

Push down on shoulders while patient shrugs

Arm abductionC5

Resist outward arm motion at shoulder

Elbow flexionC6

Resist forearm curling

Wrist extensionC6

Resist lifting hand back (wrist extended)

Elbow extensionC7

Resist straightening arm from flexed position

Finger flexionC8

Resist gripping fingers into fist

Intrinsic hand musclesC8/T1

Test finger spreading, hand grip strength

Diagnostic Imaging

Diagnostic Imaging HierarchyLayered Diagnostic Intelligence

Each imaging modality reveals different aspects of your cervical spine pathology. Combined, they create a complete picture for surgical planning. Clinical correlation is essential—imaging must match symptoms.

Diagnostic imaging modalities for cervical spine assessment

MRI: The Soft Tissue Blueprint

MRI

The Soft Tissue Blueprint

What It Reveals

Disc structure: Nucleus signal intensity (dark = desiccated, bright = hydrated)
Disc height: Quantifiable disc space height
Herniation pattern: Protrusion vs. extrusion; central, paracentral, or lateral location
Spinal cord: Signal changes (T2 hyperintensity = cord edema or gliosis from compression)
Nerve root: Compression, inflammation, signal changes
Ligament status: PLL thickening, calcification; ligamentum flavum thickening

Limitations

Cannot precisely show bone anatomy (cortical detail)
Cannot clearly identify calcifications
Overestimates stenosis in some cases
Does not show dynamic compression (patient must be supine)

Asymptomatic disc herniations are common (30–50% of people without neck pain have MRI findings), so imaging must match symptoms.

DEXA T-Score Candidacy Guide

T-Score	Classification	Arthroplasty Candidacy
> -1.0	Normal bone	Excellent
-1.0 to -2.5	Osteopenia	Good
-2.5 to -3.5	Moderate osteoporosis	Questionable
-3.5 to -4.0	Severe osteoporosis	Marginal
< -4.0	Very severe osteoporosis	Contraindicated

If osteoporosis is discovered, bone-strengthening medications can be started 3–6 months before surgery.

Neurophysiological Testing

EMG and Nerve Conduction StudiesFunctional Confirmation of Imaging

While MRI shows structure, neurophysiological testing shows function. These tests determine whether nerves are actually being compressed and damaged—providing functional confirmation of imaging findings.

Neural pathway visualization showing electrical signal transmission for neurophysiological testing

Measuring electrical conduction through neural pathways

Nerve Conduction Studies

Measures how quickly and effectively electrical impulses travel along nerves.

How It Works

1Small stimulating electrodes placed on skin over a nerve
2Electrical stimulation applied (patient feels mild tingling)
3Recording electrodes at another location detect the response
4Latency and amplitude are measured and compared to normal values

Normal NCS in Cervical Radiculopathy

This is expected and normal for most radiculopathy patients
Compression occurs proximal to the dorsal root ganglion
Normal NCS does NOT rule out cervical radiculopathy

Abnormal NCS Findings

Slowed conduction velocity suggests demyelination
Reduced amplitude suggests axonal injury
F-wave abnormalities can detect root-level slowing

55%

Sensitivity

100%

Specificity

Cervical Radiculopathy Criteria

All of the following criteria must be met:

1Paraspinal muscle abnormalities: Fibrillations or positive sharp waves on needle EMG
2Peripheral nerve motor abnormalities: EMG abnormalities in 2 muscles innervated by same nerve root
3Different peripheral nerve distribution: Both muscles must be in different peripheral nerves
4Sensory NCS typically normal (expected finding)
5Motor NCS usually normal or mildly abnormal

Cervical Myelopathy Criteria

One or more of the following:

1SEP abnormalities: Delayed N13, abnormal P14, reduced amplitude (most specific)
2MEP abnormalities: Prolonged CMCT, reduced amplitude, asymmetry
3Combined SEP and MEP abnormalities (most specific for myelopathy)
4Correlation with clinical and imaging findings

Clinical Utility Note

EMG/NCS is most valuable when clinical diagnosis is unclear, multiple levels of compression exist, or peripheral nerve involvement may confound diagnosis. Test results also provide prognostic information—acute denervation patterns generally indicate good recovery potential, while chronic patterns suggest slower or incomplete recovery.

Patient Selection

Patient Selection CriteriaWho Benefits from Disc Replacement?

Careful patient selection is crucial for optimal outcomes. Understanding who makes an ideal candidate, who requires careful consideration, and who should not undergo arthroplasty ensures the right surgical decision.

Patient selection criteria assessment showing candidacy evaluation

Candidacy Assessment

Ideal Candidates for Cervical Disc Replacement

Excellent candidates typically have these characteristics:

Clinical Decision Support

These criteria guide shared decision-making between you and your surgeon. Relative contraindications don't automatically exclude arthroplasty—they require careful evaluation, possibly additional testing (like SPECT/CT for facet arthropathy), and realistic discussion of expected outcomes.

Medical Optimisation

Comorbidity ScreeningComprehensive Medical Assessment

Cervical spine surgery carries specific risks related to various body systems. Thorough screening identifies conditions that increase surgical risk and allows optimisation before surgery.

Body systems overview for comorbidity screening assessment

Cardiovascular Assessment

Screening Questions

History of MI, stroke, or TIA?

Angina or chest pain with exertion?

Hypertension? Controlled?

Arrhythmias (AFib)?

Heart failure?

Key Considerations

Low risk: No cardiac history, normal exam, good functional capacity
Intermediate risk: Controlled HTN, prior MI >5 years ago, controlled AFib
High risk: Recent MI (<6 months), unstable angina, decompensated heart failure

Management

Cardiology referral if acute cardiac symptoms
Recent MI or intervention requires clearance
Significant arrhythmias need evaluation

Goal of Screening

Identify conditions that increase risk and allow optimisation before surgery—not to deny surgery but to improve safety.

Baseline Testing

Metabolic panel, coagulation studies, and specific tests as indicated form the pre-operative baseline for comparison.

Collaborative Care

Multidisciplinary Team CollaborationExpert Network Around You

Your preoperative assessment involves a coordinated team of specialists working together. Each brings unique expertise to ensure comprehensive evaluation and optimal outcomes.

Multidisciplinary team network showing interconnected healthcare specialists

Patient-Centred Collaborative Care

Spine Surgeon

Team Leader

Responsibilities

Leads assessment, makes surgical recommendations

Interprets imaging in context of clinical findings

Conducts physical examination

Discusses risks/benefits and obtains informed consent

Multidisciplinary Rounds Benefits

Diverse expert input reduces individual bias
Better risk stratification through multiple perspectives
Improved patient education with team consensus
Complex cases receive comprehensive evaluation
Recommendations documented for clinical continuity

Specialist Consultations

Clinical Algorithms

Diagnostic Decision-MakingFrom Symptoms to Surgical Planning

The path from initial presentation to surgical decision follows a systematic algorithm. Clinical correlation—matching symptoms, imaging, and neurophysiological findings—is essential for optimal outcomes.

Diagnostic Algorithm

Diagnostic decision-making flowchart for cervical spine assessment

1

Patient presents with neck pain ± arm pain

History, physical exam, red flag screening

2

Red flags identified?

No → Conservative care trial (6–12 weeks) | Yes → Urgent imaging

3

Conservative care fails or red flags present

MRI cervical spine (first-line imaging)

4

MRI shows surgically relevant pathology

CT cervical spine (bone anatomy detail)

Clinical Correlation Examples

Symptoms

Thumb/index finger pain radiating from neck
Thumb numbness
Wrist extension weakness

Imaging Findings

C5-C6 right-sided herniation
Compressing right C6 root in foramen

EMG/NCS (if performed)

Right C6 paraspinal fibrillations
Abnormalities in musculocutaneous and median nerve territories (C6 muscles)

Clinical Correlation

Perfect symptom-imaging-EMG correlation

Surgical Planning

C5-C6 anterior discectomy, placement of cervical disc prosthesis

Key insight: Imaging findings alone don't determine surgery. The correlation between symptoms, examination, imaging, and neurophysiological testing guides the optimal treatment plan.

Informed Consent

Shared Decision-MakingYour Voice in Your Care

Surgery is a partnership. Your surgeon provides expertise, evidence, and recommendations. You provide your values, preferences, and goals. Together, you reach a truly informed decision.

Evidence-Based Discussion

Surgeon-patient consultation dialogue for shared decision-making

Outcome Statistics

80-95%Pain Relief

85-95%Success Rate

25-30%Adjacent-Segment Risk (Fusion)

10-15%Adjacent-Segment Risk (Arthroplasty)

Valid Informed Consent Requires

Patient understands nature and purpose of surgery
Patient understands realistic alternatives (conservative care, fusion, arthroplasty)
Patient understands material risks (infection, nerve injury, vascular injury, etc.)
Patient understands likely benefits (pain relief, neurological improvement)
Patient's decision is voluntary (no coercion)
Patient has opportunity to ask questions

Consent Process

1Surgeon explains in understandable language (not jargon)
2Patient asks questions (encouraged)
3Surgeon clarifies any concerns
4Patient signs formal consent document
5Documentation in medical record

Risks to Discuss

5-15%Overall Complication Rate

0.5-2%Infection Rate

1-3%Neurological Injury

10-30%Temporary Dysphagia

Your Questions Are Welcome

Take time to understand your options. Write down questions before your consultation. There is no such thing as a "silly" question when it comes to surgery on your spine. Your surgeon wants you to feel confident and informed.

Optimisation Strategies

Preoperative OptimisationPreparing Your Body for Surgery

The weeks before surgery are an opportunity to optimise your body for the best possible outcomes. Each area of preparation contributes to faster recovery, fewer complications, and better long-term results.

Preoperative optimisation journey showing preparation stations

Physical Therapy & Conditioning

4–8 weeks before surgery

Why It Matters

Improves baseline strength and endurance

Teaches proper body mechanics

Establishes baseline for postoperative rehabilitation

Reduces postoperative pain and disability

Recommendations

Cervical spine stabilisation exercises
Upper extremity strengthening
Postural training
Range of motion preservation
Education on proper lifting, ergonomics

Your Role in Optimisation

Active participation in preoperative optimisation is one of the most important things you can do to influence your surgical outcome.

Medication List Essential

Bring a complete list of all medications (including supplements) to your preoperative visit for review and planning.

Advanced Planning

Advanced Surgical PlanningYour Unique Anatomy, Precisely Mapped

Modern imaging technology allows your surgeon to create patient-specific surgical plans based on your exact anatomy. This precision planning translates to better outcomes and reduced surgical time.

3D surgical planning visualization with implant positioning overlays

Patient-Specific 3D Surgical Model

3D Reconstruction

Patient-specific 3D models generated from CT data for precise anatomical understanding.

Clinical Benefits

Visualise your unique anatomy before surgery
Identify unusual structures or variations
Plan optimal approach trajectory

Anatomical Variants Requiring Recognition

Implant Selection Strategy

Disc Space Dimensions

Length, width, height measured on imaging; implant sized to fit

Endplate Geometry

Flat vs. lordotic implants chosen based on segmental anatomy and lordosis needs

Implant Material

Metal-on-plastic, metal-on-metal, or other bearing surfaces based on patient factors

Surgeon Familiarity

Experience with specific implants is important for optimal outcomes

Institutional Protocols

Hospital often standardises on 1–2 implant systems for consistency

Final sizing is typically done intraoperatively after disc removal and endplate preparation, but preoperative planning narrows options and aids surgical efficiency.

Assessment for OutcomesThe Foundation of Outstanding Surgery

Preoperative assessment is the foundation of excellent surgery. Every element—history, examination, imaging, neurophysiological testing, specialist input, shared decision-making, and optimisation—contributes to achieving the best possible outcomes.

Assessment quality wheel showing interconnected goals for surgical success

Patient Safety

Identifies and optimises medical conditions that increase surgical risk

Surgical Technique

Detailed imaging, testing, and clinical correlation optimise approach and implant positioning

Outcome Optimisation

Appropriate patient selection, careful technique, realistic expectations lead to better outcomes

Patient Confidence

Thorough evaluation demonstrates thoroughness and builds confidence in surgical team

Legal/Ethical Standards

Informed consent ensures ethical practice and informed decision-making

Assessment Transforms Outcomes

Patients with excellent preoperative assessment typically experience:

Fewer complications

Faster recovery

Better pain relief

Improved neurological recovery

Higher satisfaction

Better long-term outcomes

Your Role in Assessment

As a patient, you contribute by:

Providing honest symptom history
Accurate timeline, location, functional impact
Communicating medical history
All prior surgeries, medical conditions, medications, allergies
Asking questions
Understanding the plan and risks
Following preoperative instructions
NPO, medications, arrival time
Participating in optimisation
Smoking cessation, physical therapy, weight management if applicable
Setting realistic expectations
Understanding recovery timeline and early postoperative course

Final Thoughts

By participating actively in your preoperative assessment, you ensure that you and your surgical team have the information needed to make the best possible decisions about your spine health and surgical care.

"Understanding your preoperative assessment process—including the important role of neurophysiological testing—transforms you from a passive patient into an informed partner in your own healthcare. This partnership, built on thorough assessment and clear communication, is the foundation for excellent surgical outcomes."

Correct diagnosis

Appropriate treatment

Optimal planning

Minimised complications

Excellent outcomes

Informed patients

Preoperative Assessment Cervical Disc Replacement