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Less-Invasive Techniques Shrink Rehab Period in Joint Replacement

An emphasis on innovative, less-invasive surgical techniques for knee and hip replacement and the use of technologically advanced prostheses is shrinking the rehab period in joint replacement surgery, says Andrew Spitzer, M.D., associate director of the Institute for Joint Replacement.

Patients whose surgery is performed using less-invasive surgical techniques are often discharged from Cedars-Sinai within three days after surgery and are back to normal functioning within one to two months. One such technique Spitzer uses in hip replacement surgery is a short posterior incision that minimizes the dissection of muscle and reduces the damage to surrounding tissues.

"Ten years ago we had patients staying in the hospital for one to two weeks after their joint replacement surgery (both knee and hip) and now we've reduced that to one to three days in some cases," he said.

As the baby boomer generation ages, the number of hip replacement surgeries is expected to increase.

One of the newer hip prostheses is a triple-tapered polished collarless stem
replacement, a technology that Spitzer helped to design. "This cemented prosthesis represents an interesting twist in the history of hip replacements. Its unique feature is that it is the only prosthesis in its particular variety that has been observed to actively create positive remodeling of the bone," he said.

Over time, prostheses tend to cause the bone around them to waste in such a way that the body doesn't load them properly. Eventually, the bone surrounding the replaced joint becomes weaker and thinner and can fail catastrophically.

"There is some early evidence to indicate that this new type of prosthesis may be causing the bone to positively remodel or reinforce itself in a physical manner. Cemented stems, paradoxically, have been felt to be more applicable to an older population. This particular prosthesis may create an indication for use in younger patients, particularly in those who may otherwise be looking at multiple joint replacements during their lifetime," he said.

Another technically advanced implant being used at Cedars-Sinai is mobile-bearing knee
replacement prosthesis.

"The mobile-bearing prosthesis is a different concept than the more traditional fixed-bearing knee replacement. The plastic that's between the two metal pieces actually moves in multiple planes," Spitzer said. "This allows for a reduction in the wear associated with knee replacements by as much as 95 percent. Since the wearing surface has been one of the weaker links in the replacement process, we¿re looking at expanding the longevity and durability of these surgeries, thereby greatly reducing the need for revision surgery."