Improved results of primary total hip replacement

Figures & data

Table 1. Age, sex, and diagnosis at primary surgery in 4 time periods

	All	1987–1992	1993–1997	1998–2002	2003–2007
	n (%)	n (%)	n (%)	n (%)	n (%)
Mean age	69	69	70	70	70
Sex (% women)	70	70	70	70	69
n	110,882	24,651	24,659	28,817	32,755
Diagnosis
Osteoarthritis	79,700 (72)	16,597 (67)	17,130 (70)	20,976 (73)	24,997 (76)
Rheumatoid arthritis	3,465 (3.1)	942 (3.8)	902 (3.7)	851 (3.0)	770 (2.4)
Sequelae after fracture	11,933 (11)	3,299 (13)	3,133 (13)	2,886 (10)	2,615 (8)
Sequelae dysplasia	8,125 (7.3)	2,037 (8.3)	1,795 (7.3)	2,032 (7.1)	2,261 (6.9)
Sequelae dysplasia, total luxation	879 (0.8)	414 (1.7)	214 (0.9)	141 (0.5)	110 (0.3)
Sequelae Perthes'/epiphysiolysis	1,442 (1.3)	319 (1.3)	329 (1.3)	388 (1.3)	406 (1.2)
Ankylosing spondylitis	477 (0.4)	105 (0.4)	116 (0.5)	144 (0.5)	112 (0.3)
Acute fracture	969 (0.9)	55 (0.2)	116 (0.5)	233 (0.8)	565 (1.7)

Table 2. The most commonly used implants, in 4 time periods

Most commonly used	1987–1992	1993–1997	1998–2002	2003 and later	Total
a. Acetabular implants
Charnley (DePuy)	11,947	11,789	10,431	7,270	41,437
Exeter (Stryker)	2,609	2,029	2,866	3,871	11,375
Reflection (Smith & Nephew)	0	818	3,505	6,613	10,936
Titan (DePuy)	1,903	2,262	1,861	1,884	7,910
Elite (DePuy)	597	409	1,261	2,950	5,217
Tropic (DePuy)	1,065	1,443	1,232	82	3,822
Spectron (Smith & Nephew)	2,128	1,117	406	0	3,651
Trilogy (Zimmer)	0	381	1,012	1,517	2,910
SP (Link)	474	393	776	1,211	2,854
b. Femoral implants
Charnley (DePuy)	12,556	12,291	10,039	6,323	41,209
Exeter (Stryker)	2,652	2,090	3,163	6,304	14,209
Titan (DePuy)	2,669	2,776	3,069	2,913	11,427
Corail (DePuy)	1,096	2,232	2,107	3,392	8,827
Spectron (Smith & Nephew)	51	183	2,552	5,971	8,757
ITH (Smith & Nephew)	1,230	1,446	983	64	3,723
SP (Link)	1	394	582	1,128	2,105
c. Caput implants
Exeter (Stryker)	2,269	2,088	3,206	6,598	14,161
Universal (Smith & Nephew)	1,652	2,475	3,705	5,898	13,730
Landos (Ortho Medic)	3,824	5,037	2,527	2,566	13,954
Fjord (Ortho Medic)	0	392	2,841	3,431	6,664
SP II Lubinus (Link)	0	388	584	1130	2,102

Table 3. Fixation method for 4 time periods

	1987–1992	1993–1997	1998–2002	2003 and later	Total
	n (%)	n (%)	n (%)	n (%)	n (%)
Cemented	19,837 (82)	19,833 (81)	23,161 (81)	24,104 (75)	86,935 (79)
Uncemented	3,142 (13)	3,355 (14)	3,715 (13)	4,410 (14)	14,622 (13)
Hybrid ^b	1,028 (4.3)	1,317 (5.4)	1,363 (4.7)	684 (2.1)	4,392 (4.0)
Inverse hybrid ^c	60 (0.2)	45 (0.2)	482 (1.7)	3,140 (9.7)	3,727 (3.4)
Total	24,067 (100)	24,550 (100)	28,721 (100)	32,338 (100)	109,676 (100) ^a

^a The fixation method was not reported for 1,206 prostheses.

^b Hybrid means cemented femur component and uncemented cup.

^c Inverse hybrid means uncemented femur component and cemented cup.

Figure 1. Number of hips inserted using Simplex, Palacos, or cement types resembling Palacos (green), in 4 time periods. Blue represents other cement types.

Table 4. Numbers of revisions due to specific causes for the 4 time periods

Cause of revision	All	1987–1992	1993–1997	1998–2002	2003–2007
Loose femur ^a	3,522	1,936	1,175	325	86
Loose acetabulum ^a	3,043	1,789	868	313	73
Aseptic loosening ^b	5,328	2,984	1,681	526	137
Dislocation	1,177	258	333	338	248
Infection	706	160	175	168	203
Fracture	392	164	123	62	43
Pain	668 (175 ^e)	319	220	91	38
Osteolysis acetabulum ^c	266	130	109	23	4
Osteolysis femur ^c	301	163	109	26	3
Total ^d	8,094	3,806	2,504	1,125	659

^a Aseptic loosening of one component.

^b Aseptic loosening of one or both components.

^c Osteolysis without loosening.

^d More than one cause of revision may be reported; thus, the sum of the different causes does not equal the total number of revision procedures.

^e In 175 patients, pain was the only reported cause of revision.

Figure 2. Numbers of revisions for different causes, in 4 time periods.

Figure 3. Kaplan-Meier survival plots. Revision for any cause in 4 time periods. A. All prostheses. B. All cemented prostheses. C. All uncemented prostheses. D. All hybrid prostheses.

Table 5a. Relative risk of overall revision (due to any cause), aseptic loosening of acetabular component, aseptic loosening of femoral component, dislocation, and infection adjusted for age sex, and diagnosis (OA vs. other). All prostheses, n = 101,550

A	B		C		D		E		F
Total
1987–1992	1		1		1		1		1
1993–1997	0.81	<0.001	0.69	<0.001	0.67	<0.001	1.58	<0.001	1.18	0.2
	(0.77–0.86)		(0.63–0.75)		(0.62–0.72)		(1.32–1.90)		(0.94–1.47)
1998–2002	0.51	<0.001	0.43	<0.001	0.23	<0.001	1.87	<0.001	1.11	0.4
	(0.47–0.55)		(0.37–0.49)		(0.20–0.26)		(1.56–2.26)		(0.88–1.40)
2003–2007	0.77	<0.001	0.36	<0.001	0.19	<0.001	2.21	<0.001	2.13	<0.001
	(0.68–0.85)		(0.28–0.47)		(0.15–0.24)		(1.80–2.72)		(1.69–2.68)
First year
1987–1992	1		1		1		1		1
1993–1997	1.48	<0.001	1.02	1.0	0.83	0.4	2.22	<0.001	1.99	0.01
	(1.19–1.84)		(0.59–1.75)		(0.54–1.27)		(1.56–3.16)		(1.17–3.41)
1998–2002	1.64	<0.001	0.89	0.7	0.37	<0.001	2.81	<0.001	2.05	0.007
	(1.33–2.03)		(0.52–1.54)		(0.22–0.63)		(2.01–3.93)		(1.21–3.46)
2003–2007	2.09	<0.001	0.51	0.04	0.37	<0.001	2.88	<0.001	4.60	<0.001
	(1.71–2.56)		(0.27–0.98)		(0.22–0.63)		(2.06–4.03)		(2.85–7.41)
After 1 year
1987–1992	1		1		1		1		1
1993–1997	0.78	<0.001	0.68	<0.001	0.66	<0.001	1.39	0.002	1.04	0.8
	(0.74–0.83)		(0.63–0.75)		(0.61–0.72)		(1.13–1.72)		(0.80–1.33)
1998–2002	0.42	<0.001	0.41	<0.001	0.22	<0.001	1.51	<0.001	0.93	0.6
	(0.39–0.46)		(0.36–0.47)		(0.19–0.25)		(1.20–1.91)		(0.71–1.22)
2003–2007	0.54	<0.001	0.36	<0.001	0.17	<0.001	2.09	<0.001	1.44	0.02
	(0.47–0.62)		(0.27–0.48)		(0.13–0.22)		(1.55–2.83)		(1.06–1.94)

A Time period

B All revisions RR (95% CI) and p–value

C Acetabular loosening RR (95% CI) and p–value

D Femoral loosening RR (95% CI) and p–value

E Dislocation RR (95% CI) and p–value

F Infection RR (95% CI) and p–value

Table 5b. Relative risk of overall revision (due to any cause), aseptic loosening of acetabular component, aseptic loosening of femoral component, dislocation, and infection adjusted for age sex, and diagnosis (OA vs. other). All cemented prostheses, n = 86,929

A	B		C		D		E		F
Total
1987–1992	1		1		1		1		1
1993–1997	0.92	0.01	0.87	0.012	0.81	<0.001	1.57	<0.001	1.17	0.2
	(0.86–0.98)		(0.78–0.97)		(0.75–0.88)		(1.28–1.92)		(0.91–1.49)
1998–2002	0.59	<0.001	0.64	<0.001	0.25	<0.001	2.01	<0.001	1.07	0.6
	(0.54–0.64)		(0.55–0.74)		(0.22–0.29)		(1.63–2.47)		(0.83–1.37)
2003–2007	0.72	<0.001	0.40	<0.001	0.17	<0.001	2.20	<0.001	1.82	<0.001
	(0.65–0.81)		(0.30–0.54)		(0.13–0.22)		(1.74–2.77)		(1.41–2.34)
First year
1987–1992	1		1		1		1		1
1993–1997	1.72	<0.001	1.00	1.0	1.08	0.8	2.64	<0.001	2.03	0.01
	(1.34–2.21)		(0.56–1.79)		(0.67–1.74)		(1.74–3.99)		(1.17–3.52)
1998–2002	1.84	<0.001	0.90	0.7	0.45	0.007	3.51	<0.001	1.84	0.03
	(1.44–2.34)		(0.51–1.60)		(0.25–0.81)		(2.37–5.21)		(1.07–3.18)
2003–2007	2.01	<0.001	0.36	0.009	0.20	<0.001	3.26	<0.001	3.85	<0.001
	(1.58–2.54)		(0.17–0.77)		(0.09–0.45)		(2.19–4.85)		(2.34–6.34)
After 1 year
1987–1992	1		1		1		1		1
1993–1997	0.87	<0.001	0.86	0.01	0.80	<0.001	1.29	0.04	1.01	1.0
	(0.81–0.94)		(0.77–0.97)		(0.74–0.87)		(1.02–1.64)		(0.76–1.32)
1998–2002	0.49	<0.001	0.62	<0.001	0.25	<0.001	1.53	0.001	0.91	0.5
	(0.45–0.54)		(0.54–0.73)		(0.21–0.28)		(1.18–1.99)		(0.68–1.21)
2003–2007	0.52	<0.001	0.42	<0.001	0.17	<0.001	2.02	<0.001	1.23	0.2
	(0.44–0.60)		(0.31–0.58)		(0.13–0.23)		(1.44–2.81)		(0.88–1.71)

A–F, see Table 5a.

Figure 4. Kaplan-Meier survival plot. Revision for any cause. A. 1987–2007. B. 1998–2007.

Table 5c. Relative risk of overall revision (due to any cause), aseptic loosening of acetabular component, aseptic loosening of femoral component, dislocation, and infection adjusted for age sex, and diagnosis (OA vs. other). Charnley prostheses with Palacos or Simplex cement, n = 28,225

A	B		C		D		E		F
Total
1987–1992	1		1		1		1		1
1993–1997	1.27	<0.001	1.12	0.3	1.28	0.001	1.75	0.002	1.15	0.5
	(1.13–1.44)		(0.89–1.40)		(1.11–1.49)		(1.23–2.50)		(0.78–1.70)
1998–2002	0.61	<0.001	0.44	<0.001	0.21	<0.001	2.21	<0.001	0.88	0.6
	(0.51–0.72)		(0.30–0.63)		(0.15–0.28)		(1.54–3.18)		(0.58–1.35)
2003–2007	0.88	0.3	0.31	0.003	0.25	<0.001	2.61	<0.001	1.76	0.02
	(0.70–1.12)		(0.14–0.67)		(0.14–0.45)		(1.68–4.07)		(1.11–2.79)
First year
1987–1992	1		1		1		1		1
1993–1997	2.01	0.002	0.97	1.0	1.10	0.8	2.78	0.003	1.49	0.3
	(1.30–3.09)		(0.33–2.89)		(0.46–2.61)		(1.42–5.45)		(0.66–3.34)
1998–2002	2.00	0.002	0.91	0.9	0.61	0.3	3.30	<0.001	1.50
	(1.23–3.07)		(0.31–2.72)		(0.23–1.63)		(1.71–6.39)		(0.68–3.35)
2003–2007	2.31	<0.001	0.24	0.2	0.17	0.09	3.63	<0.001	2.89	0.01
	(1.45–3.68)		(0.03–2.02)		(0.021.30)		(1.79–7.40)		(1.30–6.43)
After 1 year
1987–1992	1		1		1		1		1
1993–1997	1.22	0.002	1.13	0.3	1.29	0.001	1.42	0.1	1.06	0. 8
	(1.07–1.39)		(0.89–1.42)		(1.11–1.50)		(0.93–2.17)		(0.68–1.66)
1998–2002	0.46	<0.001	0.39	<0.001	0.18	<0.001	1.83	0.008	0.70	0.2
	(0.38–0.56)		(0.26–0.58)		(0.13–0.26)		(1.17–2.87)		(0.41–1.17)
2003–2007	0.62	0.004	0.33	0.009	0.27	<0.001	2.36	0.009	1.34	0.3
	(0.45–0.86)		(0.14–0.76)		(0.15–0.48)		(1.24–4.50)		(0.74–2.45)

A–F, see Table 5a.

Table 5d. Relative risk of overall revision (due to any cause), aseptic loosening of acetabular component, aseptic loosening of femoral component, dislocation, and infection adjusted for age sex, and diagnosis (OA vs. other). Other cemented prostheses, n = 58,704

A	B		C		D		E		F
Total
1987–1992	1		1		1		1		1
1993–1997	0.83	<0.001	0.86	0.02	0.68	<0.001	1.50	0.002	1.15	0.4
	(0.76–0.90)		(0.75–0.97)		(0.61–0.75)		(1.17–1.94)		(0.84–1.58)
1998–2002	0.60	<0.001	0.72	<0.001	0.27	<0.001	1.94	<0.001	1.17	0.3
	(0.55–0.66)		(0.61–0.85)		(0.24–0.32)		(1.51–2.51)		(0.86–1.60)
2003–2007	0.67	<0.001	0.41	<0.001	0.15	<0.001	2.08	<0.001	1.90	<0.001
	(0.59–0.76)		(0.30–0.56)		(0.11–0.20)		(1.58–2.73)		(1.40–2.57)
First year
1987–1992	1		1		1		1		1
1993–1997	1.60	0.003	1.07	0.8	1.11	0.7	2.53	0.001	2.47	0.02
	(1.17–2.19)		(0.54–2.14)		(0.62–1.98)		(1.49–4.29)		(1.16–5.25)
1998–2002	1.79	<0.001	0.93	0.8	0.39	0.01	3.67	<0.001	2.09	0.05
	(1.34–2.40)		(0.47–1.81)		(0.19–0.81)		(2.25–5.99)		(0.99–4.40)
2003–2007	1.90	<0.001	0.36	0.02	0.20	<0.001	3.20	<0.001	4.78	<0.001
	(1.43–2.50)		(0.16–0.84)		(0.08–0.49)		(1.97–5.20)		(2.46–9.31)
After 1 year
1987–1992	1		1		1		1		1
1993–1997	0.79	<0.001	0.85	0.02	0.67	<0.001	1.26	0.1	0.96	0.8
	(0.73–0.86)		(0.75–0.97)		(0.60–0.74)		(0.94–1.69)		(0.67–1.36)
1998–2002	0.52	<0.001	0.71	<0.001	0.27	<0.001	1.41	0.04	1.03	0.9
	(0.47–0.58)		(0.60–0.84)		(0.23–0.31)		(1.03–1.95)		(0.73–1.46)
2003–2007	0.48	<0.001	0.43	<0.001	0.14	<0.001	1.88	0.002	1.20	0.4
	(0.40–0.56)		(0.30–0.61)		(0.10–0.20)		(1.27–2.78)		(0.81–1.79)

A–F, see Table 5a.

Table 5e. Relative risk of overall revision (due to any cause), aseptic loosening of acetabular component, aseptic loosening of femoral component, dislocation, and infection adjusted for age sex, and diagnosis (OA vs. other). Uncemented prostheses, n = 14,621

A	B		C		D		E		F
Total
1987–1992	1		1		1		1		1
1993–1997	0.61	<0.001	0.46	<0.001	0.16	<0.001	1.56	0.02	1.31	0.4
	(0.55–0.67)		(0.40–0.53)		(0.12–0.22)		(1.06–2.28)		(0.69–2.48)
1998–2002	0.30	<0.001	0.09	<0.001	0.11	<0.001	1.28	0.3	1.51	0.4
	(0.25–0.35)		(0.06–0.14)		(0.07–0.17)		(0.83–1.95)		(0.77–2.96)	0.2
2003–2007	0.91	0.4	0.28	<0.001	0.27	<0.001	1.93	0.005	5.51	<0.001
	(0.75–1.11)		(0.15–0.52)		(0.17–0.45)		(1.22.–3.05)		(2.85–10.66)
First year
1987–1992	1		1		1		1		1
1993–1997	0.87	0.6	1.26	0.8	0.34	0.04	1.25	0.5	1.85	0.6
	(0.55–1.38)		(0.28–5.63)		(0.12–0.93)		(0.63–2.49)		(0.17–20.42)
1998–2002	1.04	0.9	0.59	0.6	0.19	0.01	1.15	0.7	6.00	0.09
	(0.67–1.61)		(0.10–3.53)		(0.06–0.67)		(0.58–2.28)		(0.74–48.81)
2003–2007	2.08	<0.001	1.41	0.6	0.75	0.5	1.68	0.1	18.07	0.005
	(1.41–3.05)		(0.34–5.90)		(0.35–1.64)		(0.89–3.16)		(2.43–134.2)
After 1 year
1987–1992	1		1		1		1		1
1993–1997	0.60	<0.001	0.46	<0.001	0.15	<0.001	1.71	0.02	1.27	0.5
	(0.54–0.66)		(0.40–0.53)		(0.11–0.21)		(1.08–2.70)		(0.65–2.46)
1998–2002	0.25	<0.001	0.09	<0.001	0.11	<0.001	1.33	0.3	1.12	0.8
	(0.20–0.30)		(0.06–0.13)		(0.07–0.17)		(0.78–2.28)		(0.53–2.37)
2003–2007	0.62	0.001	0.18	<0.001	0.14	<0.001	2.11	0.04	3.77	0.001
	(0.47–0.83)		(0.08–0.42)		(0.07–0.31)		(1.04–2.27)		(1.70–8.38)

A–F, see Table 5a.

Figure 5. Kaplan-Meier survival plot for cemented hip prostheses: every hospital in Norway in 2 time periods. A. 1987–1997. B. 1998–2008.