MRI-detected osteophyte is a predictor for receiving total knee arthroplasty in patients with end-stage knee osteoarthritis

Abstract

in 84 knees and rheumatoid arthritis in 6 knees. The pre-operative mechanical alignment of the lower limbwas in 13.4 6.3 (0-30) varus. The knees were randomized in 1:1:1 ratio into one of the three groups conventional instruments (CON), computer navigation (NAV) and patient specific instruments (PSI). They were also randomized with regard to the 3 surgeons. Each surgeon performed 10 CON, 10 NAV and 10 PSI TKA. The three groups were matched, except there were more male patients in the PSI group. The prostheses and surgical routines were standardized. Post-operative standing long films of the entire lower limbs were taken.We recorded the tourniquet time and the operative time (skin-to-skin). We measured the femoral and tibial component positions in the coronal and axial planes and the overall lower limb alignment of the lower limb after TKA. Results: The mean tourniquet times were 49.2 12.7 minutes for CON, 68.6 14.8 minutes for NAV and 49.1 15.3 minutes for PSI groups (p < 0.001, Oneway ANOVA). Conventional instrument was more likely to result in an excessively flexed femoral component (p 1⁄4 0.001, Oneway ANOVA). Number of outliers in postoperative lower limb alignment, and other components positions in the coronal and sagittal plane showed no statistically significant difference. Conclusion: We found that the tourniquet time and operation time of using patient specific instrument in TKA were similar to that of conventional instrument, and shorten than computer navigation. The postoperative lower limb alignment and individual component positions were similar in all 3 groups except in sagittal plane where conventional instrument resulted in a significantly flexed femoral component. Although statistical significance was not achieved, the incidence of outliers was the highest in the conventional instrument group, followed by patient specific instrument and finally computer navigation. The current studied identifiedmarginal benefit of PSI in isolated component position compared to conventional instrument. A prospective study with a larger sample size and better post-op imaging modality (e.g. CT or MRI) may be needed to prove the efficacy of PSI. 860 MRI-DETECTED OSTEOPHYTE IS A PREDICTOR FOR RECEIVING TOTAL KNEE ARTHROPLASTY IN PATIENTS WITH END-STAGE KNEE OSTEOARTHRITIS L. Liu y,z, H. Kaneko y, R. Sadatsuki y, S. Hada y, A. Yusup y, M. Kinoshita y, I. Futami y, Y. Shimura x, H. Kurosawa x, Y. Saita y, Y. Takazawa y, H. Ikeda y, K. Kaneko y,z, M. Ishijima y,z. yDept. of Med. for Orthopaedics and Motor Organ, Juntendo Univ. Graduate Sch. of Med., Tokyo, Japan; z Sportology Ctr., Juntendo Univ. Graduate Sch. of Med., Tokyo, Japan; xDept. of Orthopaedic Surgery, Juntendo Tokyo Metropolitan Koto Geriatric Med. Ctr., Tokyo, Japan