• Feature
• The tragically hip

Hip

Hip replacement is the most successful, cheapest and safest form of replacement surgery. The first artificial hips were inserted in the 1930s, made of steel or chrome they were better than arthritis but had a number of drawbacks. The main problem being that the articulating surfaces could not be lubricated by the body, leading to wear and loosening and hence the need to replace the joint again, revision operations. Attempts to use teflon produced joints that caused osteolysis and wore out within two years.

The modern artificial joint owes much to the work of John Charnley at the Manchester Royal Infirmary, his work in the field of tribology resulted in a design that completely replaced the other designs by the 1970s. Charnley's design was a polyethylene design that could be lubricated with synovial fluid, joined to the femoral bone with bone cement. Wear issues only made it suitable for sedentary patients, but the improvements in friction led to the Charnley design being chosen over the other options (the designs of McKee and Ring)

In the last decade several evolutionary improvements have been made in the total hip replacement procedure and prosthesis. Many hip implants are made of a ceramic material rather than polyethylene, which some research indicates dramatically reducing joint wear. Most implants are joined without cement; the prosthesis is given a porous texture into which bone grows. This has been shown to reduce the need for revision.

The latest developments are several competing Minimally Invasive Surgery (MIS) techniques, which result in far less soft tissue damage and a much quicker recovery.

External links

• Hip Replacement Guide
• Hip joint replacement surgery description with diagrams
• Hip implant products with photographs
• Commentary & Perspective on "Alumina-on-Alumina Total Hip Arthroplasty"