The success of non-operative knee osteoarthritis treatments is of great interest to patients and surgeons. The authors in this article randomized 63 patients with knee osteoarthritis to receive extracorporeal shockwave therapy (ESWT) or sham ESWT, and followed their pain, function, and MRI T2 measurements at 5 and 12 weeks. Primary outcome was pain on a 0-10 VAS, and secondary outcomes were the Wester Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Lequesne Index, and T2 relaxation time on MRI. ESWT, compared to placebo, resulted in significantly improved pain and function at 5 and 12 weeks. There was no significant change in T2 relaxation time.