الفهرس 
Basics and Design of Computer Assisted SurgeryOnly 14 pages are availabe for public view
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Abstract
present greater details, three dimensional views or sights of internal strictures, which are invisible to the naked eye.
In the 1970s the early results of surface arthoplasty of the hip with metal on polyethylene bearing surface showed high failure rates due to polyethylene water between 5 to 10 years after implantation with the procedure being abandoned. With the introduction. Hip resurfacing arthroplasy, this procedure has gained new interest in the treatment of hip arthritis especially for younger patients. Several advantages have been advocated in the use of surface replacement of the hip compared to traditional total hip replacement. This procedure has been reported with superior results in terms of conservation and restoration of the natural anatomy and biochemical function of the hip.
Navigation techniques have been already used in various orthopedic procedures. So the idea came up to provide additional intra operative information for the hip resurfacing procedure and to improve the surgical accuracy by introducing navigation techniques.
In elderly patients THA is the perfect choice for restoration of a well-functioning, painless hip joint is the most important goal in total hip arthroplasty, Correct alignment of the total hip components means positioning of the cup and the stem relative to bony landmarks but also relative to each other in a planned orientation, systems that can meet these requirements up to now are real-time navigation technology.
Several types of CAS in Hip surfacing and THA (CT based fluoroscopic based- image free) but any new technology Most have disadvantages one of most important disadvantages is economic issue.