arthritic(n = noun.person) - a person afflicted with arthritis; "the hands of an elderly arthritic"
is a kind of patient
Derived form noun arthritis₁

   arthritic(s = adj.all) creaky, rheumatic, rheumatoid, rheumy - of or pertaining to arthritis; "my creaky old joints"; "rheumy with age and grief"
Derived form noun arthritis₁

1.  Pertaining to the joints. Sir T. Browne. [1913 Webster]

2.  Of or pertaining to arthritis; gouty. Cowper. [1913 Webster]

3.  afflicted with arthritis. [WordNet 1.5]