© 2016 Elsevier Inc. Screws, pegs and hydroxyapatite-coating are used to enhance the primary stability of uncemented cups. We present a 14-year follow-up of 48 hips randomized to four groups: press-fit only, press-fit plus screws, press-fit plus pegs and hydroxyapatite-coated cups. Radiostereometric migration measurements showed equally good stability regardless cup augmentation. The mean wear rate was high, 0.21. mm/year, with no differences between the groups. Seven hips had radiographical osteolysis but only in hips with augmented cups. Cups without screw-holes compared with cups with screw-holes resulted in better clinical outcome at the 14-year follow-up. Thus, augmentation of uncemented cups with screws, pegs, or hydroxyapatite did not appear to improve the long-term stability compared with press-fit only.
Otten, V. T. C., Crnalic, S., Röhrl, S. M., Nivbrant, B., & Nilsson, K. G. (2016). Stability of Uncemented Cups - Long-Term Effect of Screws, Pegs and HA Coating: A 14-Year RSA Follow-Up of Total Hip Arthroplasty. Journal of Arthroplasty, 31(1), 156-161. https://doi.org/10.1016/j.arth.2015.07.012