Excerpt from Citak et al. Acta Orthop. 2013 Jun; 84(3): 326–327. (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3715825/):
Between January 1996 and February 2012, we treated 4 patients with interprosthetic femoral fractures (3 of them women) (Figure 2) using a custom-made interposition device (Waldemar Link GmbH, Hamburg, Germany) (Figure 1). Mean age was 74 (59–86) years. The fractures occurred mean 18 (13–28) years after primary THA and mean 14 (10–17) years after primary TKA. At the latest follow-up, after mean 8 (0.5–16) years, revision surgery with a total femur replacement was required in 1 case due to aseptic loosening. No other complications requiring revision surgery occurred.