Artificial encapsulation of joint prostheses.
The great success of total joint replacement in surgery has been disturbed mainly by later loosening and wear-out of the plastic components. In an attempt to improve long term performance of joint prostheses and eliminate the adverse effects of wear debris, polymeric encapsulation as a main design feature has been proposed. The benefits of having an encapsulated and artificially lubricated joint prosthesis have been evaluated in tribological terms with particular reference to the UMIST shoulder joint. The selection of a number of biopolymers involved in this research project described. The possible interactions arising from the coexistence of these materials have been mechanically investigated. Much attention and a great deal of practical work has been focussed on the sealing of the capsule and on the relevant liquid permeability.