17 patients with an anterior cruciate ligament injury undergoing surgical reconstruction were randomized to receive a singular intraarticular injection of hyaluronan (HA) with or without allogeneic STRO-1+ human mesenchymal precursor cells (MPC). The purpose of this study was to determine if the administration of allogeneic immunodeficient STRO-1+ human MPC resulted in significantly improved clinical pain, function, and joint structure outcomes after 24 months when compared to HA injection alone. Results demonstrated that patients who received STRO-1+ human MPC and HA (MPC+HA) had significantly improved function and pain throughout study duration and showed significantly decreased tibial bone expansion when measured at 26 weeks.