Summary Our long range goal is to develop an image-guided workstation that uses a novel Continuum Dexterous Manipulator (CDM) and tools to enable next generation of minimally- and less-invasive procedures allowing access to regions not currently accessible with conventional surgical tools in orthopaedic surgery. The system and devices will enable treatment of bone defects such as femoroacetabular impingement, metastatic bone disease, severe osteoporosis in areas including the pelvis/acetabulum, femoral neck, peri- and sub- trochanteric regions, as well as the shin and foot, and finally traumatic fracture repair. The near-term focus of this application is the core decompression for the treatment of Avascular Necrosis (AVN) of the femoral head and reduction of pelvis fracture. We propose the development of an image-guided prototype robot-assisted surgical system for planning, real-time intraoperative monitoring, navigation, and updating of the plans. In the United States, avascular necrosis (AVN, also known as osteonecrosis) of the femoral head occurs in 10000-20000 of patients per year between the ages of 20-50 years old. The incidence of the AVN is even higher in Middle Eastern and Asian countries. AVN occurs due to the loss of blood supply to the bone, leading to the spontaneous death of the trabecular bone, which in turn may cause microfractures in the trabecular bone. Depending on the amount of femoral head involved, collapse of the articular surface will occur as the disease advances. Once collapse of the femoral head occurs in these patients, the disease course rarely regresses. Total Hip Arthroplasty (THA) will be the primary surgery of choice and will provide pain relief to those AVN patients. However, because of the young age of the AVN patients, THA is not the most desirable choice. Core decompression is a conventional techniques used for the treatment of the AVN prior to the collapse of the femoral head. Typically in core decompression the lesion area (death bone) is removed by drilling and debriding. After debriding the bone graft will be inserted and/or bioresorbable material such as calcium phosphates will be injected into the core to fill the void and provide stability. The long-term success of core decompression is dependent on many parameters that may be out of the control of surgeons given the existing tools and techniques. Some of the issues that the current conventional techniques for core decompression does not answer are: 1) complete debriding of the death bone requires significant increase in dexterity of the debriding tools, currently not available to the surgeons; 2) While it is ideal to completely remove the death bone, the extent of the bone removal may be limited by the stability requirements of the femoral head to prevent its collapse underweight bearing conditions. Biomechanical analysis of the stability of the structure, therefore, must be important part of the planning. Further, the successful implementation of t...