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
UKA is intended to be load sharing
- correct to neutral or slight varus
HTO is a load-shifting / load-sparing procedure
- over correct into valgus
Advantages UKA
1. Rapid rehabilation
Trauma
RA
Rickets / osteomalacia
Horizontal joint line important
- < 10° tilt acceptable
> 10o joint line tilt / due to femoral valgus
- continues to overload lateral compartment
Trauma
Meniscectomy
Osteonecrosis
Varus or valgus malalignment
Relief of pain
Improve function
No loss of ROM
No or slight restriction of activity
Allow heavy functional demands
Rheumatoid arthritis
Combined ankle and subtalar joint osteoarthritis
Revision
Multi-ligament injury
Older patient
Graft preparation
Calcaneal bone plug for femoral tunnel
Prepare bone plug
- decide on bone graft size needed
Fewer complications than TSR
Simpler procedure
1. RC arthropathy / > 70 / low functional demand
2. Revision TSR
3. Failed Hemiarthoplasty in proximal humerus fracture
Able to achieve relatively high level of function after STJ fusion
- previously believed that isolated STJ fusion should not be performed
- believed that triple arthrodesis was operation of choice for hindfoot
- STJ fusion has superior result with less stress on AJ
Average loss of DF 30% / PF 10%
Position of hindfoot determines flexibility of transverse tarsal (CCJ & TNJ) joints
- imperative that fusion be positioned in ~ 5o valgus
1. Persistent instability despite ORIF and LCL repair
2. Gross acute instability, not suitable for surgery
3. Delayed treatment > 4 weeks