Computer and robotic assisted osteotomy around the knee.

The outcome variability and failures of conventional osteotomy have been attributed to lack of preoperative planning and inaccuracy in performing the correction. We present a computer and robotic assisted surgery system that can aid in accurate surgical planning for realignment, and in precisely implementing the plan in theatre. The approach seeks to avoid the cost and risks associated with the use of CT, and the insertion of fiducial markers, which are characteristic of existing computer assisted surgical systems. The paper details the architecture of the system as a whole, placing particular emphasis on planning technique. It is anticipated that the increased accuracy possible with the system will prove particularly useful for correcting multi-plane deformities, which are more problematic with conventional techniques.

Robotic-assisted internal fixation of hip fractures: a fluoroscopy-based intraoperative registration technique.

The internal fixation of proximal femoral (hip) fractures is the most frequently performed orthopaedic surgery procedure. When using a sliding compression hip screw, a commonly used fixation device, accurate positioning of the device within the femoral neck-head is achieved by initially drilling a pilot hole. A cannulated component of the hip screw is then inserted over the guide wire (surgical drill bit), which is used to drill the pilot hole. However, in practice, this fluoroscopically controlled drilling process is severely complicated by a depth perception problem and, as such, a surgeon can require several attempts to achieve a satisfactory guide wire placement. A prototype robotic-assisted orthopaedic surgery system has therefore been developed, with a view to achieving accurate right-first-time guide wire insertions. This paper describes the non-invasive digital X-ray photogrammetry-based registration technique which supports the proposed robotic-assisted drilling scenario. Results from preliminary laboratory (in vitro) trials employing this registration technique indicate that the cumulative error associated with the entire X-ray guided robotic system is within acceptable limits for the guide wire insertion process.

Robotic-assisted internal fixation of femoral fractures.

Closed surgical techniques for the internal fixation of femoral fractures require orthopaedic surgeons to work in close proximity to X-rays. In addition to the occupational health risk this imposes, inexperienced surgeons often encounter great difficulty in achieving optimal positioning of fracture repair fixtures. A vision-guided robotic system has been proposed as a possible solution to these problems and an initial investigation involving two exemplar orthopaedic procedures has been undertaken. Robotic surgery assistance imposes rigorous safety-related design constraints, since the orthopaedic robot must operate in close proximity to the patient and operating staff. The design and implementation of a purpose-built robotic system for orthopaedic surgery assistance is described in this paper.