Effect of standard total knee arthroplasty surgical dissection on human patellar blood flow in vivo: an investigation using laser Doppler flowmetry.

We examined the in vivo alterations of human patellar bone blood flow that occur with surgical dissection of the extensor mechanism during total knee arthroplasty. A laser doppler probe was used to measure central patellar blood flow at baseline after quadriceps tenotomy, after partial fat pad excision, after lateral release, and after completion of the lateral release with superolateral geniculate sacrifice. The initial quadriceps tenotomy and medial arthrotomy decreased patellar vascularity to 60.4% of baseline. Fat pad resection initiated another 10.4% decline. The lateral release resulted in a patellar vascularity that was 43.6% of baseline. Finally, the loss of superolateral geniculate inflow reduced the patellar flow to 30.61% of baseline.