11 randomized controlled trials were included in this traditional meta-analysis and network meta-analysis comparing the efficacy of intra-articular injections of hyaluronic acid (IA-HA), corticosteroids (IA-CS), and placebo (IA-P) in the treatment of patients with mild-moderate knee osteoarthritis. The primary end point was the treatment response rate according to the Outcome Measures in Rheumatoid Arthritis Clinical Trials-Osteoarthritis Research Society International (OMERACT-OARSI) criteria, and the secondary end points included standard mean differences in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, function, and stiffness scores. All data came between 8 and 26 weeks post-injection time points. Network meta-analysis demonstrated significance in favour of IA-HA over both IA-CS and IA-P regarding OMERACT-OARSI response rate and WOMAC function scores, and, additionally, significance in favour of IA-HA over IA-P in WOMAC pain scores. No significant difference between treatments was observed in network meta-analysis of WOMAC stiffness scores. Based on the results of the analysis, the American Medical Society for Sports Medicine put forth the recommendation of using IA-HA for the treatment of mild-moderate knee osteoarthritis in patients over the age of 60 years.