Reverse hybrid total hip arthroplasty

Figures & data

Table 1. Demographic data for cemented and reverse hybrid THAs. Comparison of survival (in %) and relative risk (RR) of revision, with all revisions as endpoint for the total material

	Cemented	Reverse hybrid
	n = 267,755	n = 38,415
Revisions	9,975	1,426
Median follow-up (IQR)	6.2 (3.2–9.3)	3.3 (1.6–5.9)
Median age (IQR)	73 (67–79)	64 (57–72)
% Men	35	40
Deceased	65,379	2,242
Diagnosis, %
Osteoarthritis	81.0	79.0
RA/inflammatory	2.5	2.5
Sequelae hip fracture	11.2	8.0
Childhood disease	1.7	6.4
Femoral head necrosis	2.2	2.4
Others	1.3	1.5
5-year survival, %	97 (97–97)	96 (96–96)
number at risk	55,864	11,717
10-year survival, %	95 (94–95)	92 (92–93)
number at risk	52,477	2,045
RR^a (95% CI)	1 (Reference)	1.4 (1.3–1.5)

a Adjusted for age, sex, period, and diagnosis

IQR: interquartile range.

Figure 1. Flow chart of the study.

Figure 2. Cox survival analysis with adjustment for age, sex, time period, and diagnosis, and with any revision of the implant as endpoint. RR =1.4 (CI: 1.3–1.5; p < 0.001).

Figure 3. Revisions in the first 12 months after surgery. Cox survival analysis with adjustment for sex, diagnosis, and period.

Table 2. Comparison of reverse hybrid THAs and cemented THAs in corresponding age groups regarding risk of revision. Cemented THAs were defined as 1 when calculating RR. Cox analysis was used, with adjustment for gender, primary diagnosis, and period

Age group	RR^a	CI (95%)	p-value
< 55 years
All revisions	0.9	0.8–1.0	0.07
Fracture	1.4	0.8–2.5	0.3
Infection	0.7	0.5–1.1	0.08
Loosening	0.9	0.7–1.1	0.2
Dislocation	0.8	0.5–1.1	0.2
55–64 years
All revisions	1.1	1.0–1.3	0.013
Fracture	3.1	2.2–4.5	<0.001
Infection	1.1	0.8–1.4	0.7
Loosening	1.1	0.9–1.3	0.5
Dislocation	0.8	0.6–1.0	0.1
65–74 years
All revisions	1.5	1.3–1.7	<0.001
Fracture	4.0	2.9–5.3	<0.001
Infection	1.1	0.9–1.3	0.6
Loosening	1.6	1.4–2.0	<0.001
Dislocation	0.8	0.6–1.0	0.08
> 74 years
All revisions	2.0	1.8–2.3	<0.001
Fracture	5.8	4.3–7.9	<0.001
Infection	1.7	1.3–2.1	<0.001
Loosening	2.6	2.0–3.5	<0.001
Dislocation	1.2	0.9–1.6	0.2

a Cemented THA same age group =1

Table 3. Relative risk of revision due to fracture in men and women

		Men			Women
		RR^a	95% CI	p-value	RR^a	95% CI	p-value
< 55	1.4	0.5–3.4	0.5	1.4	0.6–3.0	0.4
55–64	2.1	1.2–3.5	0.006	4.9	2.9–8.3	< 0.001
65–74	2.1	1.3–3.4	0.004	6.7	4.5–9.9	< 0.001
> 74	3.5	2.0–6.0	< 0.001	7.9	5.4–11.5	< 0.001

a Cemented THA same age group =1, with adjustment for diagnosis and period.

Figure 4. Prosthesis survival with revision of either cup or stem for any reason, and with adjustment for sex, age, diagnosis, and period.

Table 4. Cox regression results for reverse hybrid brand combinations compared to cemented THAs, with adjustment for age, sex, period, and diagnosis. The endpoint was any revision. Median follow-up was calculated by "reverse Kaplan-Meier"

Prosthesis cup/stem	n	Total n	Revised RR	95% CI	p-value	Median follow-up (IQR)
Cemented THA	267,755	9,975	1			6.2 (3.2–9.3)
Elite/Corail	3,346	107	0.8	0.7–1.0	0.05	5.3 (3.5–6.8)
Titan/Corail	904	45	1.2	0.9–1.7	0.2	5.6 (4.1–8.6)
Kronos/Corail	632	22	0.9	0.6–1.3	0.5	5.5 (4.3–6.9)
Reflection all-poly/Corail	1,183	60	1.3	1.0–1.7	0.05	5.2 (4.1–7.2)
Contemporary/Corail	902	20	0.7	0.5–1.1	0.1	4.0 (2.9–5.2)
Marathon/Corail	8,856	202	1.3	1.2–1.5	< 0.001	1.6 (0.8–2.6)
Lubinus/Spotorno	515	10	0.6	0.3–1.0	0.06	5.1 (3.1–6.3)
Lubinus/Corail	1,932	54	1.2	0.9–1.5	0.3	3.1 (1.8–4.3)
Contemporary/ABG II HA	646	32	1.4	1.0–1.9	0.08	5.0 (3.9–6.8)

IQR: interquartile range.

Table 5. Cox regression results for reverse hybrid brand combinations compared to cemented THAs concerning early revision (< 1 year), with adjustment for age, sex, period, and diagnosis

Prosthesis cup/stem	n	Total n	Revised RR	95% CI	p-value
Cemented THA	267,755	3,038	1
Elite/Corail	3,346	56	1.5	1.2–2.0	0.002
Titan/Corail	904	26	2.8	1.9–4.1	< 0.001
Kronos/Corail	632	13	1.8	1.0–3.1	0.04
Reflection all-poly/Corail	1,183	18	1.4	0.9–2.3	0.1
Contemporary/Corail	902	10	0.9	0.5–1.7	0.8
Marathon/Corail	8,856	172	1.8	1.5–2.1	< 0.001
Lubinus/Spotorno	515	5	0.9	0.4–2.3	0.9
Lubinus/Corail	1,932	43	1.8	1.4–2.5	< 0.001
Contemporary/ABG II HA	646	12	2.0	1.1–3.5	0.01

Table 6. Cox regression results for reverse hybrid brand combinations compared to cemented THAs with follow-up of more than 5 years, and with adjustment for age, sex, and diagnosis

Prosthesis cup/stem	Total n	Revised n	RR	95% CI	p-value	At 8 years n	At 10 years n
Cemented THA	155,845	2,825	1			90,886	52,447
Elite/Corail	1,818	11	0.4	0.2–0.7	0.02	426	168
Titan/Corail	499	7	0.6	0.3–1.3	0.2	239	107
Kronos/Corail	369	2	0.3	0.1–1.4	0.1	74	30
Reflection all-poly/Corail	628	25	2.0	1.4–3.1	< 0.001	217	88
Contemporary/ABG II HA	311	2	0.5	0.1–1.8	0.3	51	–