PATIENT SPECIFIC INSTRUMENTATION
Each person's knees are also to some extent different. Studies have shown that good alignment of a knee replacement is important for optimal outcome. In addition, the component sizing is also important. During conventional knee replacements, conventional alignment guides, cutting jigs and implants allow customising the knee replacement (to that particular person) only to a certain degree.
A very recent technological development is "patient specific instrumentation". In this technique, MRI scan of the person's hip, knee and ankle is done few weeks before the operation. A special computer software creates the three dimensional model of the patient's knee and allows the surgeon to plan the bone cuts and component placement on a personal computer. The model also allows the best sizing option and in certain designs can also allow choosing an appropriate shape of the knee replacement.
These images are then used to create precise 3 dimensional plastic moulds which when placed on that particular patient's knee during surgery allows customised bone preparation as planned previously in the computer.
The actual surgery will still be the same as a conventional knee replacement. However, it is likely to be more accurate, reduce outliers, facilitate minimally invasive surgery, shorten the operative time, decrease blood loss, decrease fat embolism, faster rehabilitation and optimal functional outcome