Custom fitted total knee arthroplasty is a newer technology in total knee replacement surgery. It is an advanced procedure using an individualised patient-specific knee implant for replacement of all three components of the knee. The difference with custom knee replacement from other knee replacement surgeries is the use of an MRI scan prior to the surgery that provides a clear view of the shape and structure of the different components of the joint. The implants are then designed specifically to match the natural shape of the articulating surfaces of the patient’s knee based upon the MRI. Unlike other knee replacement surgeries, custom fitted total knee replacement can also be used for severe knee arthritis.
Prior to the surgery several MRI scans are taken to understand the specific anatomy of the affected joint. Along with the MRI images a special tool called a jig is also used to provide a clear view of implantation. The patient specific jigs have a built-in image guidance which simplifies the surgical procedure and improves the outcome. Based on the MRI images the surgeon plans the surgery and calculates the cutting measurements that help the surgeon to remove the necessary amount of bone, at specific angles. This customised cut provides better implantation, more reliable alignment and removal of less amount of bone.
There are several advantages to customised total knee replacement arthroplasty over the regular traditional implants, which include:
- No compromise on the size of the implant as it is patient specific
- Provides better fit of the implant as the implant conforms to the patient’s unique shape of the articulating surfaces of the knee joint
- Maximises the implants contact area decreasing the polyethylene contact stress thereby prolonging the life of the implant
- Preserves more natural bone
- Maximises proximal tibial coverage and thus reduces the risk of tibial implant caving in and loosening