A comparison of registration errors with imageless computer navigation during MIS total knee arthroplasty versus standard incision total knee arthroplasty: a cadaveric study.

Optimal component alignment in total knee arthroplasty has been associated with better functional outcome as well as improved implant longevity. The ability to align components optimally during minimally invasive (MIS) total knee replacement (TKR) has been a cause of concern. Computer navigation is a useful aid in achieving the desired alignment although it is limited by the error during the manual registration of landmarks.

Defining the errors in the registration process during imageless computer navigation in total knee arthroplasty: a cadaveric study.

Computer assisted arthroplasty was introduced as a means to optimally align implants in order to improve function and longevity. The error during the manual registration of landmarks and its effect on component alignment was investigated in this study. Five fresh frozen lower limbs were used and the registration process was performed five times by five surgeons.

Computer-assisted navigation for the assessment of fixed flexion in knee arthroplasty.

Background: Correction of a fixed flexion deformity is an important goal when performing total knee arthroplasty. The purpose of this study was to assess the accuracy of clinical assessment compared with imageless computer navigation in determining the degree of fixed flexion.

Methods: We performed navigation anatomy registration using 14 cadaver knees.

Proximity of the femoral neurovascular bundle during hip resurfacing.

A standard posterior approach was performed in 5 fresh frozen cadaveric limbs. An anterior incision was then used to measure the distance of the femoral neurovascular structures to the anterior capsule. Magnetic resonance imaging (MRI) of 11 hips was also analyzed to validate our cadaveric method.

The reliability of radiographic assessment of femoral neck-shaft and implant angulation in hip resurfacing arthroplasty.

Fifteen sets of patient radiographs were analyzed by 3 different observers on 2 occasions. Each observer measured the femoral neck-shaft angles (NSAs) of the preoperative digital radiographs and stem-shaft angles (SSAs) of the postoperative radiographs. The effect of femur position on SSA measured by digital radiographs was also investigated using a resurfaced synthetic femur.