TABLE 4. Demographics of lower extremity arthritis in the hip, knee and ankle.

	Hips	Knees	Ankles
Total	167	424	48
Primary	109 (65%)	347 (82%)	9 (19%)
Post-traumatic	14 (8%)	53 (12.5%)	26 (54%)
Rheumatoid	3 (2%)	15 (3.5%)	7 (14.6%)
Neuropathic	0	3 (0.7%)	3 (6%)
Dysplastic	18 (11%)	2 (0.5%)	3 (6%)
Avascular Necrosis	18 (11%)	2 (0.5%)	0
Other	5 (3%)	2 (0.5%)	1 (2%)

(N=639 total)

April 1998 to March 1999