An ache in the joints of the body. A little over half of those who suffer from Lyme disease will suffer an ache in the joints that may progressively become arthritis. This condition usually develops some months from the onset of the disease. The large joints of the body are the most affected, and most patients will develop problems with their wrists and knees, and also with the shoulders. There is considerable swelling in the joints, as well as tenderness, inflammation, and pain. Diagnosis and medical care are crucial, as this can turn into arthritis without treatment.