Increased bone mineral density in the non-resurfaced patella after total knee arthroplasty: A clinical and densitometric study

We report the results of a longitudinal study of 40 patients with osteoarthritis who had primary prosthetic replacement without patellar resurfacing, and were followed at 6 months postoperatively with a densitometric study and clinically at a minimum follow-up of 2 years. Densitometric analysis showed a mean preoperative density at the affected knee of 0.69g/cm 2 (CI: 0.62-0.76), compared to 0.86g/cm 2 (CI: 0.79-0.93) for the opposite knee (p=0.002). In our study population, the return to load and motion to the retained patella led to a significant increase in patellar bone density as measured by densitometry studies. This observation correlated with significant improvement in knee functional score. © 2011 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland.