Prolonging Total Knee Replacement Surgery with Innovative 3D Solutions

Despite knowing the risks of certain activies, even doctors at times find themselves on the operating table. Bill•, one such doctor and avid sportsperson, suffered 2 years of being unable to enjoy hobbies such as walking and golf because of cartilage damage in his knee. The orthopaedic experts at Materialise, in collaboration with specialists at UZ Gent, created a custom 3D-printed solution for the doctor, preventing total knee replacement surgery and putting the 'active' back into his active lifestyle.

Personalized Alternatives to Total Knee Replacement

Following a sports injury, Bill found himself with walking difficulties and pain on the medial side of his knee. Because of discomfort and soreness, he was unable to continue many of his regular physical activities. Joint aspiration was performed to provide relief, but a further MRI scan showed that the cartilage was damaged at the joint. Bill then underwent a small surgical procedure to remove loose particles of cartilage and any hard fragments; however, 2 years later, the pain still remained.

Total knee replacement is a common solution in severe cases of cartilage wear, but after consultation with Prof. Jan Victor, an orthopaedic specialist from UZ Gent, a tibial osteotomy was recommended given the patient's young age and degree of physical fitness. Because of concerns of further wear on the joint surfaces and increasing pain to the patient, the osteotomy needed to be exceptionally precise to prevent any degree of malalignment. A 2D x-ray is usually used to plan the degree of alignment needed for correction, with mechanical axes drawn up on the image. However, such a surgical plan can lack precision owing to inter- and intra-observer variability with x-ray images. To reduce this variability and increase the chance of recovery for his patient, Prof. Victor called on engineers at Materialise to help him create a personalized surgical plan.

Realignment Through 3D Reconstruction

Materialise transformed CT images into full 3D reconstructions of the patient's bones as a base for a 3D pre-operative surgical plan. To enhance the accuracy of the procedure when transferred into the operating theatre, surgical guides were manufactured to allow precise execution of the osteotomy at the desired angle. Placement of screw holes to be pre-drilled prior to osteotomy were determined to ensure reduction of the fragment to its planned corrected position, and were incorporated into the surgical guides.

Surgery That Goes the Distance

Although the cartilage wear is still there, the surgery both allowed Bill to postpone a total knee replacement, and reduced the discomfort he experiences while walking. He can now walk longer distances and has even returned to his golf game!

· Name has been changed to protect the patient's privacy.
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