80 patients undergoing primary total knee arthroplasty (TKA) were randomized to receive either an intraoperative soft-tissue balance sensor (Group 1; n=20) or knee balance by surgeon technique only (Group 2; n=20). Outcomes of interest included pain scores, time to narcotics discontinuation, the number of narcotic pills taken, the use of aids, and the incidence of pressure-balanced knees. The results showed that intraoperative and final postoperative knee motion was similar between groups. However, Group 1 patients achieved their range of motion goals sooner, with less reported pain up to 6 weeks after surgery, and discontinued narcotics sooner than Group 2. Additionally, Group 1 had a greater percentage of pressure-balanced knees and less high/low extremes than Group 2.