The Use of Patient-Specific Intra-Operative Guides for Total Knee Arthroplasty (TKA)

Purpose: We describe a new technique of total knee replacement using patient-specific guides. Postoperatively, extremity and component alignment were evaluated by full-length leg x-rays and CT scans. Material and methods: 5 patients who underwent Total Knee Replacement with this technique were included in the study. In every patient, a preoperative MRI was taken. This MRI scan leads to a patient-specific plan of implant size and positioning. The surgeon has the ability to alter the planning before the approval and manufacturing of guides (BIOMET, Vanguard Signature Personalised Arthritis Care). During the operation, the patient-specific guides find their unique position on the patient and #8217;s knee, providing exact pin placement for the distal resection guide, 4-in-1 cutting block and the proximal tibial cutting guide. The advantage of this method is providing each patient with a specific guide depending upon the proper anatomy. Intramedullary access for axis alignment is unnecessary. By providing specific guides for individual knees, each knee is dealt with differently, corresponding to its native anatomy. Perioperative time of surgery and postoperative implant position were evaluated by standing antero-posterior and lateral x-rays of the knee as well as a CT scan for rotational alignment of components. Results: The mean operative time is 65.6 minutes. The mean coronal femoral component angle is 89.2. The mean sagittal femoral component angle is 88.8. The mean coronal tibial component angle is 89.4. The mean femoral rotation angle is 0.6 degrees, and the mean tibial rotation angle is 1.2. Conclusions: We conclude that this novel technique hereby described has major benefits: less operative time and proper implant positioning, but more prospective studies are mandatory. [Arch Clin Exp Surg 2012; 1(4.000): 206-212