Does stress shielding occur with the use of long-stem prosthesis in total knee arthroplasty?

A retrospective study conducted to evaluate the possible occurrence of stress shielding with the use of long-stem tibial prosthesis in total knee arthroplasty. Forty-one patients were reviewed (twenty-three standard prosthesis, eighteen long-stem prosthesis) and forty-one unoperated knee of the contralateral limb). Patients underwent bone mineral density assessment with a dual-energy X-ray absorptiometry (DEXA) bone densitometer for the hip and bilateral knees. The mean time interval between surgery and the DEXA assessment was 87.7 months. There was no significant statistical difference (P > 0.05) in the bone mineral density patterns of the tibia with the use of either standard or long-stem prosthesis. The utilization of the long-stem prosthesis to off-load the tibia is not associated with any significant bone mineral density changes or stress shielding.