Patient Matched TKR
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.
The Patient Matched Knee Replacement Process
- The patient receives a full leg (Hip, Knee, ankle) CT scan following the Prophecy Protocol – This soft ware available in only certain hospitals
- The Scans are Uploaded to the USA
- Virtual Pre-Operative alignment is performed accordingly
- The surgical plan is then sent from the USA to Dr. Nizam to be approved
Once the surgical plan is sighted it is approved.
- The 3D Blocks are then manufactured in the USA and these custom made cutting blocks are sent to Australia
These 3D blocks are specifically designed to provide for accurate alignment, sizing and implant placement to improve function and longevity
Dr. Nizam designed the improvements (special markings) that are now added to the 3D block- measurements and surgical planning to improve this accuracy even more.
Advantages of patient matched knee replacements:
By using these 3D guides, upto 20 different steps can be eliminated cutting down operation times and exposure of the open wound – cutting down the risk of infection
- There is no femoral Intramedullary canal violation – this reduces the incidence of fat embolism into the blood stream and reduces post operative swelling / pain enabling quicker recovery. Standard instrumentation (drilling) can generate high pressures causing fat particles to enter the circulation increasing the risk of fat embolism. The 3D printed blocks eliminate this step.
- Secondary checks can also be performed in addition to the guides to further improve accuracy if needed.
- Standard instrumentation has been reported to result in mal-alignment (greater than 3 degree variation from the mechanical axis) in approximately 28% of knee replacements. These 3D blocks avoid these problems.
Knee Replacement Surgery
Knee Replacement Surgery - Post Surgery