The PROP OA study investigated whether adding a special knee brace to physical therapy and exercise produces better results than physical therapy alone in patients with knee osteoarthritis. A randomized controlled trial enrolled 466 adults aged 45 and over with symptoms of knee osteoarthritis from the English cities of Cheshire, Manchester, North Tyneside and Staffordshire. The group of patients who received the orthosis along with physical therapy and exercise had a greater improvement in KOOS-5 (0-100) scores at six months compared to the group who received only physical therapy and exercise (a difference of 3.39 points). The biggest benefit of the orthosis was in pain reduction, where a difference of 6.13 points on the KOOS scale (0-100) was observed after six months. The benefits of the orthosis decreased over time and the adverse events were minor and expected. The study concluded that the addition of a knee brace specific to the type of osteoarthritis is a safe intervention that produces small improvements and represents a potential treatment option for this common condition.