Computer-Assisted Total Knee Replacement (TKR) System: The outcome of total knee replacement surgery is particularly sensitive to variations in surgical technique. Incorrect orientation of implants and improper alignment can lead to accelerated implant wear, loosening, and sub-optimal functional performance. Even the most elaborate mechanical instrumentation systems rely on visual cues to confirm the accuracy of the limb and implant alignment, particularly rotational orientation. KneeNav-TKR is a CT based surgical navigation system that utilizes a hand held tracker in the usual saw slot of TKR mechanical guides in order to get intra-operative measurements of alignment and guidance information. Once the guides are properly aligned, bone cuts are made using a traditional oscillating saw.

Computer-Assisted ACL Reconstruction System: Although Anterior Cruciate Ligament (ACL) reconstruction is a routine procedure, accurate graft placement and tensioning remain a difficult task even with the use of arthroscopic techniques. The purpose of this research is to develop and evaluate a computer-assisted ACL system that makes efficient and precise performance of graft positioning possible. A CT-based surgical navigation system (KneeNav ACL) is being developed to orient the placement of standard guide-pin assembly. The position of the bones and guide-pin assembly are monitored simultaneously by means of an optical tracker. This computer-assisted ACL reconstruction system will allow accurate and reproducible positioning of the ACL tunnels according to a preoperative plan.