TABLE II.

Factors Associated with Subsequent Arthroplasty

Variable	Crude Rate of Subsequent Arthroplasty*	Multivariable Hazard Ratio† (95% CI)	P Value
Age in yr
50-59‡	4.3% (3/70)	1.00	—
60-79	13.7% (35/256)	3.06 (0.94, 10.01)	0.06
≥80	15.3% (35/229)	3.88 (1.16, 12.90)	0.03
Sex
Male‡	9.1% (16/175)	1.00	—
Female	15.0% (57/380)	1.72 (0.97, 3.05)	0.06
Pre-fracture functional status
Independent ambulator‡	12.8% (53/414)	1.00	—
Using ambulatory aid	14.2% (20/141)	1.09 (0.63, 1.89)	0.76
Quality of implant placement
Acceptable‡	12.7% (66/521)	1.00	—
Unacceptable	26.3% (5/19)	1.95 (0.77, 4.93)	0.16
Unable to assess	13.3% (2/15)	1.39 (0.34, 5.69)	0.65
Posterior tilt
<20°‡	11.9% (58/488)	1.00	—
≥20°	22.4% (15/67)	2.22 (1.24, 4.00)	0.008

^*Values are given as the percentage of patients who underwent subsequent arthroplasty, with the count in parentheses. N = 555; 73 events.

^†Hazard ratios adjusted for age, sex, preoperative functional status, and quality of implant placement.

^‡Reference category.