Improved accuracy of component alignment with the implementation of image-free navigation in total knee arthroplasty

• Published in: Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA sports traumatology, arthroscopy : official journal of the ESSKA, 2008-03, Vol.16 (3), p.249-257
• Main Authors: Rosenberger, Ralf E., Hoser, Christian, Quirbach, Sebastian, Attal, Rene, Hennerbichler, Alfred, Fink, Christian
• Format: Article
• Language: English
• Subjects: Accuracy; Aged; Aged, 80 and over; Arthritis; Arthroplasty, Replacement, Knee - methods; Biomechanical Phenomena; Computers; Female; Humans; Joint replacement surgery; Knee; Knees; Legs; Male; Medicine; Medicine & Public Health; Middle Aged; Minimally Invasive Surgical Procedures - methods; Navigation systems; Orthopedics; Osteoarthritis - surgery; Patients; Retrospective Studies; Software; Standing; Surgeons; Surgery; Surgery, Computer-Assisted - methods; Surgical techniques; Technology; Tibia - surgery; Transplants & implants; X-Ray
• ISSN: 0942-2056; 1433-7347
• DOI: 10.1007/s00167-007-0420-y

Accuracy of implant positioning and reconstruction of the mechanical leg axis are major requirements for achieving good long-term results in total knee arthroplasty (TKA). The purpose of the present study was to determine whether image-free computer navigation technology has the potential to improve the accuracy of component alignment in TKA cohorts of experienced surgeons immediately and constantly. One hundred patients with primary arthritis of the knee underwent the unilateral total knee arthroplasty. The cohort of 50 TKAs implanted with conventional instrumentation was directly followed by the cohort of the very first 50 computer-assisted TKAs. All surgeries were performed by two senior surgeons. All patients received the Zimmer NexGen™ total knee prosthesis (Zimmer Inc., Warsaw, IN, USA). There was no variability regarding surgeons or surgical technique, except for the use of the navigation system (StealthStation ® Treon plus ® , Medtronic Inc., Minnesota, MI, USA). Accuracy of implant positioning was measured on postoperative long-leg standing radiographs and standard lateral X-rays with regard to the valgus angle and the coronal and sagittal component angles. In addition, preoperative deformities of the mechanical leg axis, tourniquet time, age, and gender were correlated. Statistical analyses were performed using the SPSS 15.0 (SPSS Inc., Chicago, IL, USA) software package. Independent t -tests were used, with significance set at P