Osteoarthritis treatment and device

A method of reinforcing bone located in a targeted bone marrow lesion in a subchondral region of a first bone adjacent a knee joint for treating the targeted bone marrow lesion, the method comprising:

• identifying a bone marrow lesion less than 10 cm from a knee joint through use of magnetic resonance imaging (MRI) of the knee joint so as to establish a targeted bone marrow lesion for receiving treatment, the targeted bone marrow lesion occurring in a subchondral region of a first bone adjacent the knee joint, the subchondral region of the first bone occurring under an articular surface of the first bone;
• creating, in the first bone that contains the targeted bone marrow lesion in the subchondral region, a subchondral injection path to an area in and/or adjacent to the targeted bone marrow lesion for injecting an injectable fluid material into said area for reinforcing bone located in the targeted bone marrow lesion, wherein said creating preserves an existing condition of the overlying articular cartilage of the first bone adjacent the knee joint;
• and
• injecting an injectable and curable fluid material into the targeted bone marrow lesion via the subchondral injection path, wherein the injectable fluid material is a bone reinforcing material that is left in the targeted bone marrow lesion for becoming less fluid in the targeted bone marrow lesion so as to form, in situ, a bone reinforcing member for reinforcing bone located in the targeted bone marrow lesion, wherein the injectable fluid material is left in the targeted bone marrow lesion without also delivering and leaving a solid structural implant in and/or adjacent to the targeted bone marrow lesion in addition to the injectable fluid material.