Resurfacing
Concept![Birmingham Hip Resurfacing](/sites/default/files/TDwyer/Birmingham Hip Resurfacing.jpg)
Femur
- removal of femoral head cartilage
- resurfacing with metal
- cemented / uncemented
Acetabulum
- standard technique
Bearing surface
- metal on metal
Indications
Relatively young man (40 - 50)
OA
Femur
- removal of femoral head cartilage
- resurfacing with metal
- cemented / uncemented
Acetabulum
- standard technique
Bearing surface
- metal on metal
Relatively young man (40 - 50)
OA
Extraskeletal bone formation in periarticular tissues
- HA crystals within osteoid matrix
Different to calcification
- osteoid matrix laid down
1. Myositis Ossificans
- post traumatic
Top 6 conditions associated with DVT
- stroke
- THR
- multi trauma
- TKR
- hip fracture
- spinal cord injury
Not one of the 12 doctors was an orthopaedic surgeon
Heparin / LMWH / fondaparinux
- confirmed effectiveness
Infection (1% risk deep infection)
Wound Haematoma
Bleeding / Transfusion
Dislocation (2 - 3% recurrent)
NVI
Fracture
DVT/PE (Fatal PE 1/1000 with chemoprophylaxis)
LLD (average 1cm, stability more important)
Medical complications
- pneumonia, UTI, CVA. IHD
Death
Limp (LLD, 1 year with anterolateral approach)
Intrinsic
Infection
Loosening
Thigh pain in uncemented
- micro motion at distal end of stem
- modulus mismatch
Stress fracture / insufficiency fracture
- pubic rami, sacral
Intra-operative fracture
Prosthesis failure
Subtle instability
Extrinsic
Primary THR 1%
Revision THR 3%
DDH 5%
Sciatic nerve 90% of nerve palsy
Other
- femoral nerve
- CPN
- ulna / radial nerve from positioning
Direct
Laceration
- exposure / sciatic and superior gluteal nerve
- drill reamer / obturator nerve
- spike of cement / obturator nerve
Most common reason for litigation against orthopaedic surgeons in THR
Usually from lengthening
1. Nerve palsy
Sciatic nerve - tolerate average 4.4cm lengthening
Common peroneal nerve - tolerate average 2.7 cm lengthening
Lengthen by up to 15-20% of the resting nerve length
- but in reality is unknown and multifactorial
Increased incidence with press-fit component
- especially if under ream
Don't under-ream >1mm
In osteopenic bone
- line to line reaming
- i.e. ream to outer diameter of cup
This also avoids leaving gaps at floor
- very common if under-ream by 2mm