With regards to my knee will this OA get better, become worse or stay the same if I employ physical therapy?

Physical therapy for knee osteoarthritis is worth doing. It will not reverse the joint damage, but it consistently reduces pain and improves function.

The evidence is consistent across multiple randomized trials. A 2011 systematic review found that strength training and exercise therapy each reduce pain and disability, with effect sizes ranging from small to large depending on the program [1]. A 2000 trial showed that manual physical therapy combined with exercise produced a 170-meter improvement in 6-minute walk distance and a 599-point improvement on the WOMAC scale compared to placebo, with only 5% of the treatment group needing surgery versus 20% of the placebo group [2]. A 2020 meta-analysis confirmed that muscle strength training increases lean mass and muscle thickness in older adults with knee OA [4].

The key question is whether the condition itself gets better or worse. OA is a progressive disease of cartilage breakdown, and no exercise program has been shown to reverse that structural damage. What physical therapy does is strengthen the muscles around the knee, improve joint stability, and reduce the load on damaged cartilage. The 2013 cartilage-loading study found that squatting caused temporary cartilage deformation that recovered within 15 minutes, with no difference between mild OA and healthy knees [5]. That suggests exercise is not accelerating joint damage.

The risk of physical therapy is low. Temporary pain during exercise is common but resolves. A 2016 study of progressive resistance training after hip replacement found that 38% of patients had short-term pain flares, but 78% of those resolved by the next session [3]. No serious adverse events were reported in any of these trials.

My call: physical therapy will improve your symptoms and function, but it will not change the underlying disease course. The knee will likely continue to worsen slowly over years regardless, but physical therapy buys you better function and less pain during that progression. Confidence: high.