Anatomic Reconstruction of Hip Joint Biomechanics with the Bone Preserving Silent Micro Hip (TM) Prosthesis

Background: The design and the surgical technique of the Silent Micro Hip are different compared to other hip stems due to a conical shape for fixation within the metaphyseal femur. The purpose of the present study was to evaluate hip joint biomechanics of the Silent Micro Hip in comparison to other implants. Implant-specific differences are highlighted. Material and Method: 150 consecutive patients (each group 50 Silent Micro Hip, Nanos and SL-Plus MIA) were analysed retrospectively. For evaluation of biomechanical parameters pre- and postoperative X-rays (pelvic AP views) were used. Results: The horizontal femoral offset and the limb length showed no significant difference between the Silent Micro Hip and the Nanos or SL-Plus MIA stem at the reconstructed hip. An almost anatomic reconstruction of hip joint biomechanics was reached with all three types of implants. Conclusions: The Silent Micro Hip allows for almost anatomic reconstruction of hip joint biomechanics. Short-term results support the bone-preserving reconstruction with a proximal femoral load transfer. Further studies on the mid- and long-term outcomes are ongoing.