The Evolution of Polyurethane Orthopaedic Polymeric Casting Systems

Abstract

Within the past several years polyurethane polymeric casting systems have been increasingly used by orthopaedic medical personnel as an alternate material to the traditional plaster of Paris in immobilizing various parts of the body. This is occurring because of advances being made in the utilization of polyurethane technology for this purpose. Over the past 25 years a number of different polymeric systems have been evaluated for orthopaedic cast use with only limited success due to one or more deficiencies present making the use of them less desirable than the standard plaster of Paris casting material. This paper traces the evolution of orthopaedic casting materials starting from plaster of Paris. The chemistry of the curing reaction of the several polymeric materials is discussed together with a definition of the chemical requirements for a functional casting material. Special emphasis is given to the polyurethane systems which have proven to be quite adequate in their function and are predicted to replace a significant portion of plaster of Paris casting materials in the future.