Dr. Nizam has done the largest study in the English literature that looks at Patient Specific Instrumented (Patient Matched Knee replacements) to determine its accuracy in bone resection in Knee replacement surgery.
Published Article: Accuracy of Bone Resection in CT assisted 3D Printed PSI Knee Replacements
In short Dr. Nizam wanted to see how accurately his surgical precision in resecting arthritic bone was, depending on the 3D printed blocks that were specifically printed and sent from the USA for each patient undergoing Knee Replacement. The study found that 94% of the time the resection error if any was less than 1.5mm (that’s how accurate this knee replacement surgery is). There were NO infections in these patients and 99% of them had excellent range of motion. The amount of bone resected will then determine how well the implant sits, and this directly affects how patients perform and succeed in surgery with achieving excellent clinical outcomes.
The other study that is being conducted will give some answers in the near future with special Xray – EOS scans to determine alignment.
Normally surgeons usually use preoperative Xrays in planning of surgery to template component sizes.
Some of this process of planning and sizing also takes place during surgery.
The patient matched instrumentation uses Xrays and 3-dimensional Magnetic Resonance Imaging to give the surgeon a customized template (model) for each patient (to compliment their anatomy). This enables the surgeon to precisely choose prosthesis size and proper alignment and placement.
Customized “blocks or instrumentation” can take upto 2-4 weeks to be made from the time of Xrays and MRI scan as the images have to be sent to specialized a centre. In this case USA.