Table 3.

Trends in rates of arthroplasty (per 100,000 persons per year) by arthroplasty site, in the group with no inflammatory or autoimmune conditions and the group with inflammatory arthritides

	1991	2005	Average annual change, % (P)*
Arthroplasty type in patients with noninflammatory conditions
Total knee	49.05	134.42	6.6 (<0.001)
Total hip	42.53	73.12	3.9 (<0.001)
Partial hip	29.62	31.37	0.02 (<0.001)
Total shoulder	1.52	4.25	6.9 (<0.001)
Partial shoulder	1.80	4.31	6.7 (<0.001)
Arthroplasty type in patients with inflammatory arthritides
Total knee	2.74	2.88	−0.06 (<0.001)
Total hip	1.84	1.52	−1.6 (<0.001)
Partial hip	0.24	0.39	2.5 (<0.001)
Total shoulder	0.21	0.17	−3.5 (<0.001)
Partial shoulder	0.06	0.14	3.6 (<0.001)

^*P values were derived from coefficients in Poisson regression analysis.