Forty-three patients with hip osteoarthritis (OA) were randomized into receiving intra-articular injections of hyaluronic acid (HA) or platelet-rich plasma (PRP). The primary outcome of interest was pain intensity as measured by the Visual Analogue Scale (VAS). The secondary outcomes of interest included the Italian version of the Western Ontario and McMaster Universities Arthritis Index (WOMAC), which included subscales for pain, stiffness and function (disability). The study results demonstrated that pain scores measured by VAS and WOMAC decreased significantly between the baseline and 16 week follow-up in the HA group. Furthermore, WOMAC scores for stiffness and function also decreased significantly from baseline to 16 week follow-up only in the HA group whereas it was insignificant in the PRP treatment arm. VAS pain scores at 16 weeks were significantly in favour of the HA group compared to the PRP group.