Prolotherapy for knee osteoarthritis Hesham El-Dosoky, Saad M El Zokm, El Sayed Abd El-Hamid, Yousra Abo State The Scientific Journal of Al-Azhar Medical Faculty, Girls 2019 3(1):33-43 Background and aim Osteoarthritis (OA) is the most common type of chronic arthritis and represents a major cause of pain and disability. Prolotherapy is an injection of hypertonic dextrose used for painful chronic musculoskeletal pain conditions, including knee OA. Patients and methods This study was done to evaluate the effect of prolotherapy in treatment of knee OA. It was carried out on 200 patients with mild to moderate knee OA. The patients were classified into two groups: group 1 (100 patients) was treated by prolotherapy at 1, 5, and 9 weeks with re-evaluation after 6 months, and group 2 (100 patients) was treated by NSAIDS and physiotherapy for 6 months and served as a control group. Results The 6-month post-treatment visual analog scale and Western Ontario and McMaster Universities Osteoarthritis Index showed significant difference in pain, stiffness, and functional disability (P=0.001 and 0.043; 0.032 and 0.027; and 0.007 and 0.015, respectively) in both groups when compared with the baseline. However, on comparing both groups after treatment, we noticed significant difference in pain and disability favoring group 1 (P=0.031 and 0.048, respectively), whereas stiffness did not show significant difference between them (P=0.83). By knee ultrasound, degree of synovitis showed significant difference in groups 1 and 2 when compared with the baseline (P=0.004 and 0.007, respectively), but other parameters showed no significant differences. However, when comparing both groups after treatment, we noticed significant difference in cartilage thickness favoring group 1 (P=0.01), whereas other parameters did not show significant difference between them, although the degree, signs, and symptoms of knee effusion were improved in favor of prolotherapy group. Conclusion Prolotherapy is a promising line for treatment of knee OA. Prolotherapy reduces pain and improves the functional status in patients with knee OA.