A novel and secure technique of stemmed acetabular cup implantation in complex hip reconstructions: a comparative study and technical note

Purpose The stemmed acetabular cup (SAC) can be considered in several complicated situations. This type of prosthesis uses the iliac isthmus, which is most often preserved, thus allowing solid anchorage. Its implantation is prone to mechanical complications intraoperatively, such as extra-isthmic effraction, fracture, and early aseptic loosening. The aim of our study was to compare a new technique using a flexible motorized reamer combined with isthmus catheterization (Group A) versus the standard technique deploying a rigid reamer alone (Group B). Materials and methods A retrospective analysis was carried out of the SACs implanted at our hospital. The main evaluation criterion was visualization of extra-isthmic effraction (EIE) of the stem. Results Fifty-six SACs (Integra Lepine (R), Genay, France) were implanted, 31 in group A and 25 in group B. The mean follow-up was 21.6 months +/- 22.3. This study found fewer EIEs using a flexible motorized reamer (0 versus 5, p = 0.014), less perioperative bleeding (p = 0.054), and less aseptic loosening in group A (p = 0.034). There was no difference in terms of infection or other mechanical complications post-operatively between the two groups. Conclusion Using iliac catheterization combined with a flexible motorized reamer when implanting a SAC helps to avoid EIE and it also appears to reduce complications such as peri-operative bleeding and early aseptic loosening. We recommend use of this surgical technique rather than a rigid reamer alone, and this new technique should allow widespread and more accessible use of this specific type of implant.