Does cup position differ between trabecular metal and titanium cups? A radiographic propensity score matched study of 300 hips

Figures & data

Figure 1. A Continuum cup (A) and a control group cup (B).

Table 1. Demographic and surgical data of study population. Values are number (%) unless otherwise specified

	Study group	Control group
Factor	n = 139	n = 150
Turku ^a	50 (36)
Coxa ^b	42 (30)
Varberg ^c	47 (34)
Hvidovre ^d		150 (100)
Females	53 (38)	60 (40)
Age, median (SD)	65 (8.9)	65 (12)
BMI, median (SD)	28 (3.4)	27 (3.5)
Femoral head size
32 mm	53 (38)	29 (19)
36 mm	86 (62)	121 (81)
Liner
Hi-wall		150 (
Neutral	98 (70)
Oblique	30 (22)
10° elevation	11 (8)

^aTurku University Hospital, Turku, Finland

^bCoxa Hospital for Joint Replacement, Tampere, Finland

^cVarberg Hospital, Varberg, Sweden

^dHvidovre University Hospital, Copenhagen, Denmark

Table 2. Median cup angles and percentages of cups in the Lewinnek safe zone in the Continuum cup study group and the other uncemented cups control group

Factor	Study group	Control group
Cup angles, mean (95% CI)
Inclination	43 (41–45)	43 (41–44)
Anteversion	19 (18–20)	17 (15–18)
Turku ^a
Inclination	42 (39–46)
Anteversion	15 (13–17)
Coxa ^b
Inclination	45 (42–49)
Anteversion	24 (22–26)
Varberg ^c
Inclination	43 (40–46)
Anteversion	19 (16–21)
Hvidovre ^d
Inclination		43 (41–44)
Anteversion		17 (15–18)
Cups in the safe zone, % (n)
Inclination	67 (93)	81 (122)
Anteversion	76 (105)	67 (100)
Both	52 (72)	55 (82)

^a–dSee Table 1.

Figure 2. The scatter plot depicts Martell radiographic analysis, which compares the distribution of 2 groups in the safe zone.