3D-surface scan based validated new measurement technique of femoral joint line reconstruction in total knee arthroplasty

Journal of Experimental Orthopaedics

Table 1 Comparison of radiographic and 3D-surface scan measurements: JL difference pre- to postoperative

	Mean	SD	Median	Max	Min
Radiographic analysis^a
Medial JL difference (mm)	-2.2	± 0.1	-2.2	-2.0	-2.3
Lateral JL difference (mm)	-0.4	± 0.3	-0.6	0.5	-0.6
3D Structured Light Scanner analysis
Medial JL difference (mm)	-1.3	± 0.1	-1.2	-1.2	-1.4
Lateral JL difference (mm)	0.2	± 0.1	0.2	0.3	0.1
Difference in between techniques
Medial JL difference (mm)	-0.9		-1.0
Lateral JL difference (mm)	-0.6		-0.8

LDFA Lateral distal femoral angle, JL Joint line, SD standard deviation, Max Maximum, Min Minimum, ^a0° Flexion without rotation error (reference measurement), negative sign expresses ‘proximalisation’