The use of tourniquets in total knee arthroplasty (TKA) for patients with knee osteoarthritis is controversial. Although surgical techniques are more easily applied in a shorter time; there are some disadvantages associated with tourniquet use in orthopedic surgery. The aim of this study was to evaluate the effect of the tourniquet time on quadriceps strength by isokinetic muscle strength measurements in patients undergoing TKA. Prospective controlled study. Twenty-five knees of 25 patients with primary degenerative joint disease who underwent TKA were evaluated preoperatively and postoperatively at weeks 6 and 12 and month 6 by isokinetic knee extensor muscle strength testing at and American Knee Society Score (AKSS). The tourniquet time of all patients was recorded, and the preoperative results of all patients were compared with those postoperatively. The mean 60º/s angular velocity quadriceps peak torque was significantly lower postoperatively in patients with a longer tourniquet time. Isokinetic tests showed a significant negative correlation between the tourniquet time and mean muscle strength (week 6: r = 0.718, p < 0.01; week 12: r = 0.651, p < 0.01; month 6: r = 0.672, p < 0.01). The highest correlation with tourniquet time was obtained 6 weeks after surgery. Additionally, strong negative correlations were observed between the AKSS and tourniquet times (Knee Score: r = 0.904, p < 0.01; Knee Functional Score: r = 0.878, p < 0.01). Lower postoperative mean quadriceps strength in patients with a longer tourniquet time, suggesting that the tourniquet time affects the quadriceps muscle strength witl longer times resulting lower muscle strength.
Knee osteoarthritis;muscle strength;quadriseps;tourniquet time