Author(s)

Dominik Drnek, Nicolas Haffner, Armin Sadjed, Peter Ritschl

Vienna Hospital Association, Orthopedic Clinic Gersthof, Vienna, Austria.

Serous Purpose: There is limited information in the literature surrounding the use of patient-specific instrumentation (PSI) by a large number of surgeons. This prospective observational study was therefore designed to evaluate the logistics of using PSI for total knee arthroplasty (TKA) in a multi-surgeon environment, as well as its accuracy in positioning components. Methods: Of 73 patients enrolled in this study, 3 were excluded after the surgeon decided intraoperatively to switch to conventional instrumentation. Results: Mean operative time was 77.6 minutes. The component size had to be changed in 19 patients and bone cuts corrected in 12. In 65 of the 70 cases (92.9%), mechanical alignment was within the optimal range from 3° varus to 3° valgus, with the remaining 5 cases considered outliers (7.1%). Mean overall mechanical alignment was 0.3° varus (standard deviation, ±2°). There was a distinct variance with regard to the position of the tibial component in the sagittal plane. Conclusions: PSI can be effectively incorporated in larger, multisurgeon practices. Although high accuracy was observed for overall mechanical alignment and component positioning in the frontal and sagittal planes, further attention must be paid to the tibial slope. We highly recommend the use of the extramedullary alignment rod to the proper position of the tibial block, as well as double-checking the slope before performing bone cuts.

Patient-Matched Instrumentation; Patient-Matched Cutting Blocks; Total Knee Arthroplasty; Radiological Results

Drnek, D. , Haffner, N. , Sadjed, A. and Ritschl, P. (2014) Patient-specific instruments as a standard procedure in total knee arthroplasty: Logistics and postoperative radiological results in 70 patients. Case Reports in Clinical Medicine, 3, 57-63. doi: 10.4236/crcm.2014.31014.