Radiate - To travel outward from a point. “The pain radiates from my neck to my elbow.”
 
Rheumatoid Arthritis - Chronic inflammatory disease with destruction of joints. Considered by some to be an autoimmune disorder in which immune complexes formed in joints excite an inflammatory response towards own tissues.
 
Rotator Cuff - The group of muscles which comprise the shoulder. See Encyclopedia
Runners’ Condition - Where the kneecap (patella) rubs on the surface of the femur rather than following its normal tracking over the knee joint. This condition is due to stress or overuse. Symptoms include knee pain, just under the kneecap after running, progressing to knee pain at rest. Treatment includes rest and stretching exercises for the quadriceps and hamstring muscles.