48 single or double blinded, prospective, randomized control trails that used human subjects and compared the therapeutic effects of intra-articular hyaluronic acid with intra-articular injection of a placebo to treat osteoarthritis of the knee were analyzed to determine if the qualitative conclusions by authors about the therapeutic effects of hyaluronic acid was affected by industry sponsorship or financial conflicts of interest. Results of the systematic review indicated that industry funding may have an effect on the conclusions provided within the study and that clinicians should be aware of potential financial conflicts of interest in authors reporting on the topic of intra-articular injection of hyaluronic acid for treatment of knee OA.