Ankle Arthrodesis
Results
90% fusion rates
Lose70% sagittal plane ROM
Disadvantages of Arthrodesis
Non union rates up to 12%
Decreased gait speed
Poor mobility over uneven surfaces
90% fusion rates
Lose70% sagittal plane ROM
Non union rates up to 12%
Decreased gait speed
Poor mobility over uneven surfaces
Always use the most lateral scar
- blood supply comes from medial aspect
- want to avoid a large lateral flap of dubious quality
- cross transverse scars at 90o
- minimum 7 cm skin bridge
Options
- can do trial / sham incision down to capsule
1. Always resurface
2. Never resurface
3. Selectively resurface
Controversial
- literature divided on issue
Historically
- poor outcomes due to poor implant design
- now improved designs
- non resurfacing also improved due to better design and improved techniques in regard to tracking and rotation
Indications
- anteromedial disease
- patient points to anterior medial joint line only as source of pain
Pre-op x-rays
- AP and lateral
- Rosenberg to assess lateral joint
- long leg AP view to assess alignment
Pre-op examination
Usually occurs in patients over 60
- due to decreased vascularity & collagen weakness
Younger patient on steroids / growth hormone
Occasionally occurs in young athlete with excessive contracture
Often preceded by quadriceps tendinosis
Adolescent apophyseal avulsion
- treat non operatively
- unless displaced > 2 cm
Adult
- soft tissue avulsion
Usually associated with sporting activities
- skiing
- water skiing
Violent contraction
- knee extended
- hip flexing
Usually young patients
- 15 - 40
15% compound
High velocity injury
- MBA
- MVA
- pedestrian v car
- fall from height
EMST principles
- need for transfusion not uncommon
Rheumatoid arthritis
Combined ankle and subtalar joint osteoarthritis
Avoiding convergence of ACL tunnel and femoral tunnels of popliteus / LCL
- drill LCL and popliteus femoral tunnels anterior to avoid more posterior ACL tunnel
- avoid drilling LCL femoral tunnel proximal, to avoid more proximal ACL tunnel
Moatshe et al. Am J Sports Med 2017
- avoiding tunnel convergence
- aim LCL and popliteus tunnel anteriorly 35o