Zimmer Orthopedic Implants

Building acceptance for titanium alloy implants

Today, titanium alloy is routinely used for orthopedic implants -- hips, knees, and fracture fixation -- and Zimmer was a pioneer in their introduction. Today, it's hard to believe that just a decade or so ago, orthopedic surgeons were quite resistant to a change from chrome-cobalt. Titanium had a lower modulus of elasticity (more flexible) than chrome-cobalt. The general fear was, a flexing implant would break bone cement, the implant would prematurely loosen -- and reoperation would be necessary.

One of the first titanium alloy hip implants introduced was the "Sarmiento" hip, developed by Augusto Sarmiento, M.D. currently professor and chairman emeritus at the University of Miami Medical School, and Loren Latta, PhD, associate professor of biomedical engineering at the same institution. Sales at first were disappointing, due to surgeon concerns about a "flexing" implant.

A visit to Miami with Drs. Sarmiento and Latta revealed that surgeon misconceptions about flexing went beyond simply the implant. Most important, the two experts explained, was not just the modulus of any one component in the bone-cement-implant system, but the modulus of the combination. Dr. Latta sketched out a diagram to explain the results of biomedical testing in the Miami labs, which showed that, when considered as a combination of cylinders and sleeves of different moduli, titanium alloy was the perfect material from which to manufacture implants.

ProClinica captured the discussion on tape, and began assembling a monograph on the subject of titanium implants. The Sarmiento-Latta backgrounding was combined with case experience with both titanium arthroplasty and fixation devices, offered by other teaching and private-practice clinicians. Individual chapters in the monograph were abridged to spreads and run as advertorials in the leading orthopedics journals.

Result: Zimmer distributors reported high interest from orthopedists, who began trying the new Sarmiento and subsequent Zimmer titanium alloy implants. Today, the material is standard, and the principles advanced in the monograph and advertorials are well accepted by the profession and industry.

The first page of an 8-page advertising insert developed by ProClinica for Zimmer. The following pages were a jarring difference from ordinary implant ads, which showed the devices on white backgrounds with studio lighting. Hip, knee and external fixation systems were shown, close-up, in the OR -- bloody by consumer ad standards, but demonstrating to viewing orthopedists how leading surgeons use Zimmer implants.