Artificial Support and Replacement of Human Organs - Biomimetics: Biologically Inspired Technologies - page 461

Figure 18.12 (See color insert following page 302) The SynCardia CardioWest total artificial heart. (With

permission from SynCardia Systems, Inc., Tucson, AZ.)

18.9 TOTAL JOINT REPLACEMENTS

Attempts have been made since decades to find a cure for the treatment of arthritis which affects
mainly the hip and knee joints. Earlier treatments included fusion of joint spaces (arthrodesis),
removing some part of bone (osteotomy), disrupting the nerve supply and cleaning (d ´ bridement)
of the joint spaces to remove the irregular coverings over the bone in the joints. In an attempt to
smoothen the joint spaces, calcium deposits, parts of cartilage, and extraneous bony spurs were
removed. Attempts were made to cover the joint spaces with fat, muscle, fascia, or metals like
gold, magnesium, and zinc. These strategies had limited success, and they proved short lived at
the best. Smith Peterson in 1925 in Boston proposed using a glass molding of the ball of the hip
joint to reduce friction (Neff, 1954). However, it was soon apparent that glass could not withstand
the stress of the normal body weight in the erect posture. Other materials like plastics and
stainless steel were tried, and steel was proven to be biocompatible. Other material used was
cobalt-chromium to allow a resistant free joint movement; this met with some mixed success.
Austin Moore and Frederick Thompson independently demonstrated the feasibility of replacing
the entire ball of the hip, but this only addressed the problems of the arthritic femoral head, since
the hip socket (acetabulum) was not replaced.
In 1938, Jean Judet and his brother used acrylic material to replace the hip surfaces; although
unsuccessful initially due to the limited adhesiveness offered by acrylic, this was the precursor for
using the dental fast setting acrylic in joint replacement (Lukes and Merckelbach, 1958). John
Charnley is credited with using polyethylene to create the hip joint socket and used to achieve a
smooth surface between the metal ball component and the new socket, which was cemented using
polymethyl acrylate (Mallory, 2004). This essentially established the field of total hip replacement
(Wroblewski, 2004). Around 100,000 hip replacements are performed annually in the United
States. The aspect of breakdown in the cement fixation has been the area of intense research in