Three-dimensional femur morphology analysis for the optimal location of subtrochanteric osteotomy with an implanted Wagner cone stem in total hip arthroplasty for Crowe type IV developmental dysplasia of the hip

Table 2 Femur–femoral stem matching

Level (cm)	Shortest diameter of the medullary cavity (mm)	Diameter of Wagner cone femoral stem^a (mm)
Level (cm)	Shortest diameter of the medullary cavity (mm)	13#	14#	15#
0	14.2 ± 3.6	12.6	13.6	14.6
0.5	13.3 ± 3.4	12.1	13.1	14.1
1	12.5 ± 3.1	11.7	12.7	13.7
1.5	12.1 ± 3.0	11.3	12.3	13.3
2	11.5 ± 2.7	10.8	11.8	12.8
2.5	11.2 ± 2.6	10.4	11.4	12.4
3	11.1 ± 2.6	10.0	11.0	12.0
3.5	10.9 ± 2.7	9.5	10.5	11.5
4	10.7 ± 2.6	9.1	10.1	11.1
4.5	10.6 ± 2.6	8.7	9.7	10.7
5	10.5 ± 2.5	8.2	9.2	10.2
5.5	10.4 ± 2.4	7.8	8.8	9.8
6	10.3 ± 2.4	7.4	8.4	9.4
6.5	10.1 ± 2.3	6.9	7.9	8.9
7	10.0 ± 2.2	6.5	7.5	8.5
7.5	9.9 ± 2.3	NA	NA	NA
8	9.8 ± 2.2	NA	NA	NA

NA—not available
^aThe level 25 mm below the proximal–medial end of the Wagner cone femoral stem was the same level just below the lesser trochanter

ISSN: 1749-799X