Rahimzadeh P, et al. - Researchers investigated the effects of platelet-rich plasma (PRP) injection and prolotherapy (PRL) on the level of pain and function of the knee joint in patients with osteoarthritis (OA). They suggested a significant decrease in the overall Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score of patients who undergo either PRP therapy or PRL. In the overall WOMAC score, this positive change led to an improvement in the quality of life of patients with knee OA shortly after the first injection. Compared to PRL, PRP injection was found to be more effective in the treatment of knee OA.