Kongkhet Riansuwan, MD Banchong Mahaisavariya, MD2011-02-222011-02-222010-02-092010-02-09The Thai Journal of Orthopaedic Surgery; Volume 32 Number 1-2 March-September 2007; 25 - 30http://imsear.searo.who.int/handle/123456789/132566Image-based navigation is recently accepted as one of the most profitable devices utilized to improve the accuracy of many procedures in orthopaedic surgery. Actually, navigation-assisted surgery systems were initially used in neurosurgery in the late 1980s. The interactive computer system is able to match the co-ordinate pre-or intraoperative images, patient’s anatomy and the surgical instruments by using tracking and registration process. The initial image-based navigation system has based upon preoperative computer tomography (CT) images and clinical application has been successfully introduced in spinal instrumentation since 1994.1-2 However, time consuming, comsplicated techniques and error in the registration process known as a pair-point matching remain the major concern and may cause CT-based navigation less popularity with time.en-USThe Royal College of Orthopaedic Surgeons of Thailand, Bangkok, ThailandArticles