I just presented a case study presentation on a patient I saw in my last clinical rotation. The purpose of the presentation was to explore 3rd Generation Autologous Chondrocyte Implantation (ACI) indications and contraindications for therapy.
To briefly summarize, rehab protocols and movement restriction post-op depends GREATLY on the site and size of the site grafted with chondrocytes. The patient in the case presented had chondrocytes grafted to the articular surface of his patella. Compression of the grafting site can decrease chondrocyte proliferation by more than half of un-compressed controls. This compression is not immediately reversible, either, as chondrocyte proliferation begins to plateau at 7 days post op (in animal studies).
Different portions of the patella articulate with the femur depending on the angle of knee bend. The portion of the patella which was grafted with juvenile chondrocytes would have articulated with the femur between 30 and 60-70 degrees. Tension through the quadricep inside that range would compress the patella and grafting site directly into the femur and hurt chondrocyte proliferation.
In order to effectively decide on a protocol, we, as autonomous practitioners of PT, have a foundation in sciences (such as biomechanics, kindesiology, cell biology, research) to keep up to date with novel surgical procedures. We have the skills, abilities, and informational background to make clinical decisions for patients as technology continues to advance in the medical field. Don't get left behind.
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