In the latest in our season of articles exploring the role of technology in knee surgery, Jim Newman discusses one tool that’s proving particularly useful in partial knee replacements where patients have unusual anatomy.
A huge part of knee replacement surgery takes place long before the patient ever reaches the operating theatre. As a knee surgeon, I need to know the particular dimensions of a knee in order to know precisely where to cut. Whilst every knee is different, the ‘landmarks’ that guide every knee specialist’s decisions are usually much the same – the operative word being ‘usually’.
Sometimes, perhaps as a result of a fracture to the thighbone, a birth defect or a skeletal disorder such as rickets, those landmarks are not where you expect them to be, which renders the traditional tools unreliable.
The custom knee replacement
It’s in situations such as these that I turn to custom knee replacement technology. A scan of the limb – not just the knee but the hip and ankle too – provides precise dimensions of the knee joint and illustrates how weight is distributed along the leg and through knee. The scan then forms the basis for a 3D printed model of the knee, which fits exactly on the patient’s knee and acts as the perfect cutting guide.
I believe this is a classic example of technology being used in a way that augments traditional techniques whilst keeping the knee surgeon in control. I do the cutting. I can even use standard instruments to double check the model. The technology is an assistive tool and nothing more. But the model gives me reference points that can improve my cutting accuracy in cases of unusual anatomy, and it gives me planning time before the op, so I can think about the implant type, its positioning and the procedure without any need for the patient to be present.
For patient and knee surgeon, that’s time well spent.
If you’d like to discuss your knee pain, and the ways we might alleviate it, talk to me or any of the knee consultants at Yorkshire Knee Clinic on 03453 052 579.