Authors : A.P. Schulz , S. Magerlein , S Fuchs , A. Unger , L. Simon , B. Kienast , M. Faschingbauer and A. Paech
Abstract: Trauma surgeons are often less exposed to large caseloads of primary osteoarthritis, compared to purely `elective`orthopaedic surgeons. The experience in total knee arthroplasty is thereby markedly On the other hand, posttraumatic knee arthrosis is often accompanied by severe deformity and axis deviation. In theory, navigated arthroplasty can overcome some of the problems in this setting. Aim was the evaluation of the navigated technique of Total Knee Arthroplasty (TKA), including the technical difficulties, the learning curve and the feasibility in severe bony deformity. Setting is a level I trauma center. Patients and Methods: Between July 2004 and December 2005 we treated 49 Patients with a mean age 62 yrs. (32-82). All had a severe Arthritis of the knee joint due to trauma (diagram 1), 58% were male, in 51% the treatment was under the Workers injury compensation scheme. On average patients had 3.02 previous operations (1-9, including arthroscopies). In all cases a navigational system (PRAXIM, Tronche/France) was used with infrared-tracking and bone-morphing software. The implant was a mobile bearing LCS knee (DePuy/USA). Study setup was prospective, follow up on average 14.5 months (11-25) including the Knee Society Score results, In 4 cases the procedure was finished in a conventional technique, reasons were decision of the surgeon, a missing femoral cut block and a broken screw of the tracker-fixation. In one case a hinged prosthesis was implanted due to instability. There was no failure of the navigational system. There was a clear learning curve. Preoperative extension deficit was improved from average 7.1� (0-30�)-1.67� (0�-10�) postop., flexion contracture improved from av. 95�-103�. The combined knee society score improved from 83 points preoperatively to 157 points at F/U. Navigated knee endoprosthesis is reliable tool for the trauma surgeon with few technical problems. Especially for surgeons with less experience in TKA, planning of implant size and position is very helpful. With posttraumatic deformity the surgeon can gain valuable information and assistance to improve alignment and ligamentous balancing.
A.P. Schulz , S. Magerlein , S Fuchs , A. Unger , L. Simon , B. Kienast , M. Faschingbauer and A. Paech , 2007. Clinical Results of Navigated Total Knee Arthroplasty in Patients with Posttraumatic Deformity and Arthrosis . Research Journal of Medical Sciences, 1: 178-182.