The iASSIST system is a portable, accelerometer base with electronic navigation used for total knee arthroplasty (TKA) which guides the surgeon to align and validate bone resection during the surgical procedure. The purpose of this study was to compare the radiological outcome between accelerometer base iASSIST system and the conventional system. Method: A prospective study between two group of 36 patients (50 TKA) of primary osteoarthritis of the knee who underwent TKA using iASSIST ™ or conventional method (25 TKA in each group) from January 2018 to December 2019. A single surgeon performs all operations with the same instrumentation and same surgical approach. Pre-operative and postoperative management protocol are same for both groups. All patients had standardized scanogram (full leg radiogram) performed post operatively to determine mechanical axis of lower limb, femoral and tibial component alignment. Result: There was no significant difference between the 2 groups for Age, Gender, Body mass index, Laterality and Preoperative mechanical axis(p>0.05).There was no difference in proportion of outliers for mechanical axis (p=0.91),Coronal femoral component alignment angle (p=0.08),Coronal tibial component alignment angle (p=1.0).The mean duration of surgery, postoperative drop in Hb, number of blood transfusion didn’t show significant difference between 2 groups (p>0.05). Conclusion: Our study concludes that despite being a useful guidance tool during TKA, iASSIST does not show any difference in limb alignment (mechanical axis), Tibial and femoral component alignment when compared with the conventional method.

Background: The iASSIST (Zimmer) system is an accelerometer base navigation tool use for total knee arthroplasty (TKA) which guides surgeon to take bone cuts during surgery. The purpose of this study was to compare the functional outcome between accelerometer base iASSIST system and the conventional system. Method: A prospective study between two groups of 28 patients (14 iASSIST and 14 conventional) of primary osteoarthritis of the knee who underwent TKA using Zimmer iASSIST ™ or conventional method from January 2018 to December 2019. A single surgeon performs whole operations with the same instrumentation and same surgical approach. Pre-operative and postoperative management protocol are same for both groups. Preoperative oxford knee score, SF12 and Knee society score was taken 1 week prior to surgery and postoperative scores was taken 3 weeks after surgery. Results: There was no difference between the two groups for age, height and weight (p > 0.05). No significant difference was observed in SF 12(Physical and mental score),OKS and knee score preoperatively and postoperatively . Significant difference was observed in knee society functional score preoperatively and postoperatively between 2 groups but no significant difference was observed in difference of score. Significant correlation observed in preoperative short form(SF)12 physical component score (PCS) and preoperative oxford knee score. Conclusion: Our study concludes that despite being a useful guidance tool during TKA, iASSIST does not show any difference in functional and satisfaction outcomes when compared with the conventional method.