Features of an ideal replacement arthroplasty

1. Patient
   • Good range of movement
   • Complete pain relief
2. Implant
   • Mechanical stability
   • Low coefficient of friction
   • Low wear
   • Biocompatible
3. Surgery
   • Secure fixation to skeleton
   • Revisable in event of component failure

Materials used for manufacturing hip joint prostheses

• Ultra high molecular weight polyethylene
• Cobalt-chromium-molybdenum alloys
• Cobalt-chromium alloys
• Ceramic 

Surgical Options

1. Total hip replacement
2. Hip resurfacing

Complications

1. Infection
   • Minimised by pre-operative antibiotics
   • Anti-microbial loaded cememnt
   • Laminar airflow ventilation in operating room
   • Thorough scrubbing, use of disposable gowns, changing gloves and good skin preparation
   • Gentle handling of tissues, adequate haemostasis and good suturing techniques
   • Optimisation of tissue oxygenation
2. Component failure
3. Dislocation
4. Mechanical loosening
   • Minimised by dry operative field with adequate haemostasis
   • Pressurised cement (tighter fit)
   • Cement restrictors
   • Lavage systems
5. Aseptic loosening
   • Microfracture of components
   • Leads to small particulate matter in joint
   • Incites inflammatory reaction leading to cysts and loosening
6. Metal sensitivity