Table 2.

Univariate association of patient and implant factors with risk of revision after hemiarthroplasty (humeral head replacement)

Variable	# shoulders	# events	K-M estimates (95% CI)			Cox proportional hazards
			5 years	10 years	20 years	Hazard Ratio (95% CI)	p-value	overall p-value
Female	898	58	94.4 (92.7, 96.1)	92.3 (90.2, 94.5)	88.1 (84.5, 91.8)	1.0 (ref)
Male	533	56	92.1 (89.5, 94.9)	86.0 (82.1, 90.1)	80.4 (74.7, 86.5)	1.65 (1.14, 2.40)	0.008
Age at surgery						0.97 (0.96, 0.98)	<0.001
Body Mass Index in kg/m2 a						1.04 (1.01, 1.08)	0.03
ASA (1, 2)b	489	36	91.7 (88.9, 94.7)	89.1 (85.5, 92.8)	85.6 (79.9, 91.8)	1.0 (ref)
ASA (3, 4)	501	16	96.7 (94.8, 98.7)	94.6 (91.5, 97.7)	N/A	0.47 (0.26, 0.84)	0.01
Deyo-Charlson index						1.06 (0.96, 1.17)	0.22
No cement	575	45	93.0 (90.6, 95.5)	89.3 (86.0, 92.7)	84.0 (78.9, 89.4)	1.0 (ref)
Cement	870	69	93.9 (92.1, 95.8)	90.4 (87.9, 93.0)	86.0 (82.2, 90.0)	0.86 (0.58, 1.26)	0.43
Diagnosis								0.02
Rheumatoid arthritis	233	15	93.9 (90.5, 97.3)	93.0 (89.4, 96.8)	91.8 (87.5, 96.3)	1.0 (ref)
Trauma	493	44	93.7 (91.4, 96.1)	89.8 (86.6, 93.2)	84.0 (78.6, 89.8)	1.51 (0.84, 2.70)	0.17
Tumor	145	15	84.3 (76.4, 92.9)	80.9 (71.3, 91.8)	74.1 (60.0, 91.7)	3.33 (1.58, 7.02)	0.002
Osteoarthritis	348	26	94.4 (91.5, 97.3)	90.3 (85.9, 94.9)	79.9 (71.5, 89.3)	1.71 (0.89, 3.27)	0.11
Rotator cuff	137	5	96.8 (93.3, 100)	93.6 (88.1, 99.4)	93.6 (88.1, 99.4)	0.78 (0.28, 2.15)	0.63
Otherc	75	9	95.3 (90.2, 100)	85.5 (75.9, 96.4)	85.5 (75.9, 96.4)	1.97 (0.83, 4.63)	0.12

^aavailable from 9/1/1987 to present

^bavailable from 11/1/1988 to present; for 9 patients with TSA and 7 patients with hemiarthroplasty, ASA class was missing

^cOther category for underlying diagnosis includes: avascular necrosis, ankylosing spondylitis, psoriatic arthritis, gout, Charcot arthropathy, dislocation, old injury, prior history of septic arthritis

N/A, not applicable