C Ries1, W Schopf2, F Dietrich2, S Franke2, E Jakubowitz3, C Sobau2, C Heisel4. 1. Klinik und Poliklinik für Orthopädie und Unfallchirurgie, Universität zu Köln. 2. Arcus Kliniken Pforzheim. 3. Labor für Biomechanik, Klinik und Poliklinik für Orthopädie und Orthopädische Chirurgie, Justus-Liebig-Universität Gießen. 4. Zentrum für Orthopädie, Unfallchirurgie und Sportmedizin, Orthopädie Kurpfalz, Speyer-Mannheim-Heidelberg.
Abstract
BACKGROUND: Currently, short cementless femoral stems are alternative implants to treat osteoarthritis in young patients with sufficient bone quality in order to get a more proximal load transfer. The purpose of the present study was to biomechanically compare joint reconstructions resulting from implantations of a short-stemmed and a conventional hip replacement. METHODS: 100 patients (50 short-stemmed and 50 conventional) were retrospectively examined. For evaluation of biomechanical parameters standardised pre- and postoperative X-rays (pelvic AP views) were used and digitally analysed. RESULTS: The horizontal femoral off-set increased within both groups (short: 2.0 mm and conventional: 3.3 mm), with a significant increase in the conventional group. The hip centre of rotation was significantly medialised after both procedures (short: 6.0 mm and conventional: 4.2 mm). Limb length was shorter preoperatively at the arthroplasty side, but increased thereafter (short: 2.1 mm and conventional: 2.6 mm). Compared to the native contralateral side the limb length was almost equal after THA (short: 0.7 mm and conventional: 0.8 mm). CONCLUSIONS: Our study shows that an almost anatomic reconstruction of hip joint biomechanics is possible with a short-stemmed prosthesis compared to a conventional stem, regarding limb length, centre of rotation and offset. Georg Thieme Verlag KG Stuttgart · New York.
BACKGROUND: Currently, short cementless femoral stems are alternative implants to treat osteoarthritis in young patients with sufficient bone quality in order to get a more proximal load transfer. The purpose of the present study was to biomechanically compare joint reconstructions resulting from implantations of a short-stemmed and a conventional hip replacement. METHODS: 100 patients (50 short-stemmed and 50 conventional) were retrospectively examined. For evaluation of biomechanical parameters standardised pre- and postoperative X-rays (pelvic AP views) were used and digitally analysed. RESULTS: The horizontal femoral off-set increased within both groups (short: 2.0 mm and conventional: 3.3 mm), with a significant increase in the conventional group. The hip centre of rotation was significantly medialised after both procedures (short: 6.0 mm and conventional: 4.2 mm). Limb length was shorter preoperatively at the arthroplasty side, but increased thereafter (short: 2.1 mm and conventional: 2.6 mm). Compared to the native contralateral side the limb length was almost equal after THA (short: 0.7 mm and conventional: 0.8 mm). CONCLUSIONS: Our study shows that an almost anatomic reconstruction of hip joint biomechanics is possible with a short-stemmed prosthesis compared to a conventional stem, regarding limb length, centre of rotation and offset. Georg Thieme Verlag KG Stuttgart · New York.
Authors: L Pisecky; J Allerstorfer; B Schauer; G Hipmair; R Hochgatterer; N Böhler; T Gotterbarm; M C Klotz Journal: J Orthop Surg Res Date: 2020-11-26 Impact factor: 2.359