Study Of The Effect Of IASSIST Navigation Assisted Technique In Total Knee Arthroplasty On Patients With Knee Osteoarthritis And Extra-Articular Deformity

Background: The number of patients undergoing total knee arthroplasty is increasing every year and total knee arthroplasty in patients with knee osteoarthritis with associated Extra-articular deformities is one of the major challenges faced by joint surgeons.Extra-articular deformities result in abnormalities in the patient’s anatomical axis and bony landmarks,making the intramedullary positioning technique used in traditional techniques for osteotomies unreliable.iASSIST navigation is an inertial measurement unit-based technique that is highly accurate and sensitive.Compared to conventional technique,iASSIST navigation eliminates the need for intraoperative marrow opening,avoids difficult marrow cavities,reduces the probability of intraoperative bleeding and fat embolism,reduces trauma and surgury risks.As sensor positioning is not dependent on bony landmarks,the position of the osteotomy can be re-verified after the osteotomy,making the operation more flexible.Intraoperative force line can be automatically and precisely positioned,which can significantly reduce postoperative mechanical axis abnormalities and is a beneficial technique in the management of extra-articular deformities.Objectives: Comparison of the imaging and clinical outcomes of total knee arthroplasty in patients with knee osteoarthritis and Extra-articular deformities using the iASSIST navigation technique versus conventional techniqueMethods: This is a retrospective study that included 63 patients with knee osteoarthritis associated with extra-articular deformity who underwent total knee arthroplasty from July 2016 to July 2022 in the Joint Surgery and Sports Medicine Ward,First Affiliated Hospital of China Medical University,divided into 26 patients in the navigation group(experimental group)using the iASSIST navigation system and 37 patients in the conventional group(control group).Paired t-test was used to analyze the preoperative and postoperative HKA angles and KSS scores between two groups.The HKA angle,prosthetic component angle and postoperative KSS scores were analyzed between the two groups using independent samples t-test.Results: A total of 26 patients with 29 knees were included in the navigation group and37 patients with 43 knees in the conventional group.There was no statistical difference in baseline levels between two groups.The postoperative HKA angle and KSS scores were significantly improved in both groups compared to the preoperative levels.In the navigation group,the mean postoperative HKA angle was 2.07±1.38°,the mean postoperative KSS clinical score was 92.7±1.9,the mean postoperative KSS functional score was 92.3±2.9,the mean operative time was 90.7±8.9 min,and the mean blood loss was 110.33±4.9 m L.In the conventional group,the mean postoperative HKA angle was3.87±3.16°,the mean postoperative KSS clinical score 91.8±1.6,mean postoperative KSS functional score 86.8±3.8,mean operative time 92.8±9.6 min and mean blood loss293.85±9.8 m L.Conclusion: For patients with knee osteoarthritis of the knee associated with extra-articular deformity,total knee arthroplasty using iASSIST navigation technology allows for more precise component position and reconstruction of lower limb alignment than conventional technique,reducing surgury trauma,achieving effective deformity correction and allowing patients to achieve better post-operative knee function.