Courtesy: Jordi Sanchez-Ballester, FRCSOrth, Liverpool, UK
End-Stage Ankle Arthritis: Arthrodesis vs Total Ankle Replacement
Overview
End-stage ankle arthritis is a relatively uncommon condition compared to hip and knee arthritis, but it can cause significant disability.
Objectives
- Review epidemiology
- Understand surgical options
- Compare:
- Ankle arthrodesis (fusion)
- Total ankle replacement (TAR)
- Evaluate current evidence and outcomes
Epidemiology
Key Facts
- Ankle arthritis is much less common than hip or knee arthritis
- Knee replacements are performed approximately 24 times more frequently than ankle procedures
Clinical Data (Example)
- Population: ~400,000
- Annual procedures:
- 28 ankle fusions
- 7 ankle replacements
- 600 hip and knee replacements
UK Referral Statistics
- ~29,000 patients referred annually
- Only ~300 undergo surgery
Surgical intervention in approximately 1% of cases
Surgical Options
Two Primary Treatments
- Ankle Arthrodesis (Fusion)
- Total Ankle Replacement (TAR)
Current Standard
- Arthrodesis remains the gold standard treatment
Ankle Arthrodesis (Fusion)
Indications
Absolute
- End-stage ankle osteoarthritis
- Severe deformity (>15° malalignment)
- Neuromuscular deformities
- Failed ankle replacement
- Failed fracture fixation
Relative
- Younger patients (<60 years)
- High activity level
Techniques
1. Arthroscopic Fusion
Advantages
- Minimally invasive
- Day-case procedure
- Faster recovery
Outcomes
- Fusion rate — 94%
Complications
- Very low infection rate
- Minimal soft tissue issues
Postoperative Protocol
- Non-weight bearing for 6 weeks
2. Open Fusion
Indications
- Severe deformity
- Not suitable for arthroscopy
Approach
- Transfibular approach
Advantages
- Provides bone graft from fibula
Outcomes
- Fusion rate – 89%
Complications
- Higher infection risk
- Soft tissue complications
- Longer recovery
Biomechanical Consequences
- Loss of ankle motion
- Increased load on adjacent joints:
- Subtalar joint
- Chopart joint
Long-Term Effect
- Adjacent joint arthritis (~7 years post-fusion)
Clinical Outcomes
- Good long-term function
- Minimal deterioration even at long follow-up
Total Ankle Replacement (TAR)
Ideal Candidate
- End-stage arthritis
- Good alignment (<10° deformity)
- Stable ankle
- Adequate bone stock
- No osteonecrosis
Particularly Suitable For
- Rheumatoid arthritis
- Inflammatory arthropathies
- Patients with multiple joint involvement
Motion preservation reduces stress on adjacent joints
Contraindications
Relative
- Age <60 years
- Previous infection
- Severe deformity
- Ligament instability
- Osteoporosis
- Talar osteonecrosis
Advantages
- Preserves ankle motion
- Better biomechanics than fusion
Historical Challenges
Earlier implants showed:
- Poor outcomes
- Wound complications
- Persistent pain
Modern Implants
Examples
- STAR prosthesis
- Mobility prosthesis (withdrawn due to high failure rates)
- Infinity Total Ankle System (current generation)
Outcomes
Survival Rates
- ~92.7% at 5 years (early modern implants)
- ~97% at 2–4 years (newer implants)
Concerns
- Revision rates up to 32%
- Deep infection up to 4.6%
- Residual pain in 2–30%
Return to Activity
- ~50% return to low-impact sports:
- Walking
- Cycling
- Swimming
Registry Data Insights
- Higher revision rates than expected
- Higher failure rates in women
Fusion vs Replacement: Evidence
Short-Term Outcomes
- Similar patient satisfaction
Implant Survival (TAR)
- ~78% at 5 years
- ~77% at 10 years
Lower than hip or knee replacements
Pain and Function
- TAR may provide slightly better pain relief
- However:
- Higher complication rate
- Higher revision rate
Failure of Total Ankle Replacement
Management Options
- Revision TAR
- Salvage ankle fusion
Salvage Fusion Outcomes
- Worse than primary fusion
- More pain
- Reduced function
Complex Revision Cases
May require:
- Bone grafts
- Metal cages
- Long-stem implants
Associated with high complication rates
Current Trends
- Increasing number of ankle fusions
- Decreasing use of ankle replacements in some regions
Reflects preference for reliable outcomes with fusion
Ongoing Research
TARVA Trial (UK)
- Multicenter randomized trial
- Comparing TAR vs fusion
- Patients aged 50–85 years
Key Questions
- Will TAR outperform fusion long-term?
- Does motion preservation reduce adjacent arthritis?
- What is the long-term implant survival?
Key Conclusions
Ankle Arthrodesis
Advantages
- Reliable
- Cost-effective
- Durable long-term results
Limitations
- Loss of ankle motion
- Adjacent joint arthritis
Total Ankle Replacement
Advantages
- Preserves motion
- Better biomechanics
Limitations
- Higher revision rate
- Lower implant survival
Clinical Decision-Making
General Principles
- Fusion – more reliable option
- TAR – selected patients only
Patient Selection is Critical
Consider:
- Age
- Activity level
- Deformity
- Bone quality
- Comorbidities
Practical Clinical Message
When counselling patients:
- Explain both options clearly
- Discuss:
- Risks
- Complications
- Revision rates
- Functional expectations
Current Consensus
Ankle arthrodesis remains the most reliable treatment for end-stage ankle arthritis
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