gliding surface; in short order, those who cared to scrutinize their results
realized that cartilage was more special than they had previously thought.
While Smith-Petersen was not ready to completely abandon the
newfangled arthroplasty of the twenties, of sculpting the bones around an
arthritic joint, a chance observation kindled a thought about the body’s
ability to form new tissue. In 1923, the Harvard surgeon had seen a young
man who complained of a painful mass in his back. Smith-Petersen took
the patient to the operative theater and found a piece of glass that was
encased in the patient’s own scar tissue. Recalling later, he said, “... a
piece of glass was removed; it had been there for a year. It was surrounded
by a minimal amount of scar tissue, lined by a glistening synovial sac,
containing a few drops of clear yellow fluid. This benign reaction to an
inert foreign body gave rise to the thought there was a repair which might
be applied to arthroplasty. This first thought gradually developed and the
idea of the “mould” was conceived. A mould of some inert material,
interposed between the newly shaped surfaces of the head of the femur and
the acetabulum, would guide nature’s repair so that the defects would be
eliminated. Upon completion of repair the mould would be removed,
leaving smooth, congruous surfaces mechanically suited for function.”^8
Smith-Petersen therefore imagined an operation where the rounded end of
a glass cylinder would be positioned over a newly shaped femoral head;
the body’s reaction would be to grow a new fibrous tissue, ideally like the
hyaline cartilage of the femoral head, that would provide new gliding
surfaces. The glass mold was intended to be an incubator of sorts, with the
intention of coming back for a second operation, between fifteen and
twenty-five months after surgery, for simple removal of the mold.
Through trial and error, over a ten-year period, the cup was made of
glass, viscaloid (a form of celluloid), Bakelite, and Pyrex, and were tested
with variable success, starting in 1923. Breakage of the glass, reaction to
the viscaloid, and infections were occurring. Pyrex was much more stable
and unbreakable, and patients were actually growing a cartilage-like
structure on the head of the femur. Fifteen years after the first cup, or mold
arthroplasty, it was clear that glass and polymers were not strong or
durable enough for the enterprise.
Realizing that the first attempts at mold arthroplasty were not up for the
task, Smith-Petersen was discussing his failures with his Boston dentist,
Dr. John Cooke, who suggested Vitallium, a newly reported metal alloy