Joint assessment included formal physical examination of all joints with special care and attention to the weight-bearing joints (such as, knees, hips, and ankles) and to the shoulder girdle. All joints were examined for pain/tenderness, evidence of inflammation (i.e., redness, warmth, deformity, swelling or ballotable fluid), loss of function (to the extent this could be assessed in younger children and infants), and any restrictions to expected active/passive range of motion. An incidence count was reported as the number of subjects with at least one finding at baseline, regardless of side.