Implant migration and bone mineral density measured simultaneously by low-dose CT scans: a 2-year study on 17 acetabular revisions with impaction bone grafting

Figures & data

Figure 1. Postoperative images. Note the greater density in the bone graft compared with native bone. The 3 red circles indicate the ROIs of the bone mineral density measurements.

Figure 2. 3-D rendering of bone graft volume.

Table 2. Postoperative measurements of bone mineral density in the ROIs. Values are mean (mg/cm³) with 95% confidence intervals

Region of interest	Postop., day 1	Time-point 6 weeks	2 years	p-value
Native bone
cranial	137 (88–186)	145 (94–196)	132 (72 to 192)	0.2
caudal	79 (18–140)	93 (33–153)	35 (–38 to 108)	0.05
Bone graft	378 (355–401)	430 (412–448)	466 (390 to 542)	0.05

Table 1. Postoperative translations of the acetabular component. Values are mean (mm) with 95% confidence intervals

	Time-point
Axis	6 weeks	2 years
X (med. +)	–0.16 (–0.46 to 0.14)	–0.56 (–1.56 to 0.44)
Y (prox. +)	0.31 (0.11 to 0.51)	1.52 (0.42 to 2.62)
Z (ant. +)	0.00 (–0.10 to 0.10)	0.27 (–0.03 to 0.57)