erosion of the “roof” of the Teflon cup, with the impression that the metal
femoral head was working its way into the plastic cup like a hot knife
through butter, albeit over the course of a few years. Mr. Charnley began
to re-operate, and to his horror, realized that wear of the Teflon cup was
not the chief problem. Worse, “wear debris” was found around the hip
joints of patients who had suffered failure of the Teflon cups. He
discovered globs of fibrous tissue surrounding the Teflon particles within
the hip capsule. The adverse tissue reaction to a material he had initially
concluded was “inert” reinforced the idea that Teflon, despite its early
promise, was completely unsuitable for human use. To further confirm his
hunch, Charnley prepared specimens of finely ground PTFE and injected
them into his own thigh with a large bore needle. After waiting nine
months, he dissected out the nodules underneath his skin, and examining
the blobs of PTFE surrounded by an amalgam of fibrous tissue, knew that
he would never use Teflon again. A block of Teflon in the body is inert;
particles of Teflon are not. We are amazed that Charnley would inject
Teflon particles into his thigh, but considering the action of his English
forebear, John Hunter, the father of scientific surgery, who applied
syphilitic pus onto a self-inflicted scratch on his own penis as an
experiment, Charnley doesn’t seem as unhinged.
John Charnley, staring defeat in the face, was racked with guilt and was
disconsolate. For weeks he lived in total despair, his wife (he had finally
married at age forty-six) finding him awake at night, sitting up in bed with
his head in his hands. She felt that “everything was gray and there was an
all-pervading gloom.”^8 The anguish lasted for weeks, when a chance
discovery set him back on track.
In May, 1962, an industrial salesman representing a German plastics
company arrived in Wrightington and asked to speak with Charnley, or his
assistant John Craven. The salesman was selling plastic gear parts, which
were being used in the Lancashire weaving trade (still substantial in the
1960s), and surmised that Charnley would need mechanical parts for his
lab. Craven met with the salesman, and at a glance, saw the raw physical
similarity to Teflon. He obtained a four-inch sample block of the material,
high molecular weight polyethylene (HMWP), intent on showing
Charnley.
Craven showed the block of polyethylene to Charnley, who handled it,
dug his thumbnail into it, and realizing that he was able to score the