The association between cement type and the subsequent risk of revision surgery in primary total hip replacement

Figures & data

Figure 2. Patient inclusion in/exclusion from the study.

a 44,179 individuals from England and Wales were not traceable. Northern Ireland joined the NJR on February 1, 2013; however, there was no tracing service available for patients in Northern Ireland, and 609 procedures were therefore excluded from the analysis.

Table 2. Demographic and surgical characteristics at the time of the primary procedure

	Women	Men
Variable	n (%)	n (%)
Age (years)
40–54	3,943 (3)	2,633 (4)
55–64	18,346 (14)	11,489 (16)
65–74	49,140 (38)	29,249 (41)
75–84	47,546 (37)	23,550 (33)
≥ 85	9,745 (8)	3,564 (5)
ASA physical status
1	16,430 (13)	10,111 (14)
2	91,922 (71)	47,623 (68)
3	19,774 (15)	12,295 (17)
4	594 (0)	456 (1)
Surgical approach
Posterior	65,274 (51)	36,196 (51)
Other	63,446 (49)	34,289 (49)
Fixation
Cemented	87,928 (68)	45,899 (65)
Hybrid	35,537 (28)	21,643 (31)
Reverse hybrid	5,255 (4)	2,943 (4)
Bearing surface
MoP	112,999 (88)	59,696 (85)
CoP	9,633 (7)	6,528 (9)
CoC	6,088 (5)	4,261 (6)
Head size (mm)
22.25	12,374 (10)	6,170 (9)
26	8,210 (6)	3,931 (6)
28	78,479 (61)	38,334 (54)
30–32	20,959 (16)	14,336 (20)
≥36	8,698 (7)	7,714 (11)

Table 3. Number of primary procedures, revisions, crude revision rate, and PTIR by cement type

Manufacturer		Primary procedures	Revised	Crude revision rate
Brand Viscosity	Antibiotic	n (%)	n	(%)	PYAR	PTIR
All	199,205 (100)	2,494	1.25	813,034	3.07
Heraeus Medical
Palacos HV	G	97,956 (49.2)	988	1.01	299,985	3.29
Palacos HV	–	499 (0.3)	4	0.80	1,531	2.61
Palacos MV	G	379 (0.2)	2	0.53	1,374	1.46
Palacos LV	G	1,069 (0.5)	16	1.50	4,438	3.61
Stryker
Simplex MV	T	14,982 (7.5)	176	1.17	59,474	2.96
Simplex MV	E/C	13,913 (7.0)	170	1.22	63,516	2.68
Simplex MV	–	4,733 (2.4)	78	1.65	25,852	3.02
Schering-Plough
Palacos HV	G	26,270 (13.2)	499	1.90	178,318	2.80
Palacos HV	–	1,620 (0.8)	23	1.42	10,447	2.20
Palacos LV	G	1,156 (0.6)	34	2.94	8,463	4.02
Biomet
Palacos HV	G	235 (0.1)	3	1.28	1,492	2.01
Palacos HV	–	1,143 (0.6)	18	1.57	5,556	3.24
Biomet HV	G	18,495 (9.3)	229	1.24	77,584	2.95
DePuy
CMW 1 HV	G	6,841 (3.4)	99	1.45	33,854	2.92
CMW 1 HV	–	800 (0.4)	7 0.88	4,583	1.53
CMW 2 HV	G	3,418 (1.7)	34	0.99	10,158	3.35
CMW 2 HV	–	506 (0.3)	9	1.78	2,306	3.90
CMW 3 MV	G	1,887 (0.9)	53	2.81	8,532	6.21
SmartSet HV	G	3,096 (1.6)	45	1.45	14,620	3.08
SmartSet HV	–	207 (0.1)	7	3.38	950	7.36

Viscosity: HV = high, MV = medium, LV = low.

Antibiotics: G = gentamicin, T = tobramycin, E/C = erythromycin/colistin.

PYAR = prosthesis years at risk.

PTIR = prosthesis time incidence rate, per 1,000 prosthesis-years.

Figure 4. Incident rate ratio (95% CI) of revision surgery comparing different bone cements with Heraeus Palacos HV + gentamicin. Abbreviations are G = gentamicin, T = tobramycin, E/C = erythromycin/colistin, HV = high, MV = medium, LV = low viscosity. Point estimates are weighted by sample size to illustrate the number of procedures to estimate the cement type IRR.

Figure 5. Incident rate ratio (95% CI) of revision surgery comparing antibiotic-loaded cement with its plain variant. For abbreviations, see Figure 4.