The Journal of Arthroplasty, Volume 27, Issue 4, 648 - 654

Micromotion of Cementless Tibial Baseplates Under Physiological Loading Conditions

Bhimji, Safia et al.

Initial implant stability is crucial to cementless knee arthroplasty success. The objective of this study was to develop a physiological relevant methodology that incorporates torsion, shear, and compression forces to evaluate two tibial component designs that feature either a keel or cylindrical porous metal pegs. The data were compared with a simplified compression loading scenario. Results show a loading profile that combines compressive, shear, and torsional loads results in significantly larger motions than occur when loading in compression only. When comparing between a keeled and a pegged device, the new method shows significant differences in tibial component subsidence/liftoff at the anterior and posterior locations, which were lacking in the simplified test model. To accurately assess implant stability, studies should use physiological relevant loading.

Download article