Sixty-four patients suffering from adhesive capsulitis (AC) were randomized to receive a single ultrasound-guided platelet-rich plasma (PRP) injection (n=32) or conventional physiotherapy (CP) consisting of shortwave diathermy treatment and exercise (n=32). Outcomes of interest included pain on a Visual Analogue Scale (VAS), function using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, and range of motion (i.e. flexion, abduction, external rotation), which were all evaluated at 1, 3 and 6 weeks post-treatment. Furthermore, the consumption of acetaminophen was recorded at 0-1 week, 1-3 weeks, and 3-6 weeks follow-up. Results revealed no statistical significant differences in all outcomes between the PRP and CP groups (p>0.05 for all). Yet, all outcomes did statistically significantly improve with time in both groups(p<0.001 for all). The consumption of acetaminophen was statistically significantly reduced in the PRP group vs CP group at 0-1 weeks (p=0.005), 1-3 weeks (p=0.005), and 3-6 weeks (p=0.002) follow-up.