Progression of roentgenographic changes over five to eleven years and the relationship of roentgenographic changes to symptoms, function and quadriceps strength were evaluated in fifty knees (thirty-five patients). Patellofemoral arthritis progressed more than that of the weight-bearing compartments. Increased degeneration of the medial compartment occurred in less than 50 per cent of the varus knees. Severity of roentgenographic degeneration was not related to body weight. Women had more severe patellofemoral arthritis and greater limitation of activity than men. Increased patellofemoral arthritis was associated with increased pain, increased functional impairment, and decreased quadriceps strength.