essentially they consist of painful , peripheral joint manifestations : either simple arthralgia , or true arthritis differing in the degree of pain , the degree of the clinical signs accompanying the pain , the mode of evolution , and the number and the grouping of the joints affected , thus occurring in numerous clinical forms of which the two principal ones are subacute oligoarthritis with a tendency to migrate and chronic polyarthritis that gives rise to few definitive deformations .
C0003862
arthralgia
C0030193
pain