A human hip joint is a ball and socket joint comprising the head of a femur bone (femoral head) located in an acetabulum of a human pelvis. During total hip arthroplasty (THA), the hip joint of a patient is replaced with prosthetic components. The surgical procedure involves the surgical excision of the head and proximal neck of the femur bone and removal of the acetabular cartilage and subchondral bone. An artificial canal is created in the proximal medullary region of the femur, and a metal femoral prosthesis is inserted into the femoral medullary canal. An acetabular component or implant is inserted proximally in the enlarged acetabular space.
One of the most important aspects of THA is ensuring proper alignment of the acetabular component or implant with respect to the pelvis. Alignment of the prosthetic components has typically been performed relying solely on a surgeon's judgment of the spatial location of the prosthetic components. Studies have shown that failure to properly align the acetabular component or implant with the pelvis may lead to premature wear, propensity to dislocate and patient discomfort. Surgical navigation systems can assist surgeons in providing guidance in the placement of the prosthesis in the body of the patient to improve clinical outcomes. A surgeon may obtain a pre-operative scan providing medical images of the patient's anatomy of interest. During the surgical procedure, systems may provide intra-operative surgical navigation by providing surgical measurements with respect to the medical images.