The CT-Based Patient Specific Hip Joint 3D-Modeling; Potential to Create a Virtual Alignment

Abstract

Background/Objectives: The salvage proximal femoral osteotomy is performed in mild to moderate forms of osteoarthritis when the articulating surfaces are normal and relieves the subject’s pain. Because of the importance of angular mal-alignment of the femur bone at the hip junction, accurate preop planning based on patient specific anatomy is required to prevent any lower misalignment and joint problem. Patients and Methods: In this study, a virtual CT-Based modeling technique was used to a 3D-Model of the patient’s pelvis and proximal femur. The registration stage using angio-fluoroscopy was performed to calculate the proximal femur kinematic and input it into a finite element model to achieve the stress distribution pattern of femoroacetabular joint. Results: To assess the biomechanics of the joint contact surface, it is necessary to have the stress distribution in the articulating surfaces of the hip joint. The decision about the salvage surgical approach and the appropriate plan for wedge excision will be made based on the biomechanical results at the joint. FE model also provides additional information on the stress profile of the contact surface when the joint moves from full extension to full flexion. Conclusion: Use of a non-invasive 3D modeling method will remediate the surgical approach in pre-op stage. Here, the in-vivo modeling and assessment of the patient femuroacetabular contact is approved. It has been shown that the accuracy of the proposed model is comparable with the existing surgical pre-op planning.