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. Author manuscript; available in PMC: 2012 Jun 1.
Published in final edited form as: Strength Cond J. 2011 Jun 1;33(3):21–35. doi: 10.1519/SSC.0b013e318213afa8

Figure 2.

Figure 2

A. Representative subject whose combination of decreased tibia length and mass prior to her rapid growth spurt diminish risk to demonstrate high LOAD landing mechanics. Knee valgus motion during the drop vertical jump is calculated as the displacement measure between the two marked knee alignment in the X plane measured at the frame prior to initial contact and the frame with maximum knee flexion (X2− X1).

B. Knee flexion range of ROM during the drop vertical jump is calculated as the difference in knee flexion angle between initial contact and maximum knee flexion positions (ϴ1−ϴ2).

C. Completed nomogram for the representative subject (Tibia length: 32.5 cm; Knee valgus motion: 4.2 cm; Knee flexion ROM: 74.1°; mass: 30.7 kg; QuadHam: 1.64). Based on her demonstrated measurements this subject would have a 12% (62.5 points) percent chance to demonstrate high LOAD during the drop vertical jump. Her actual LOAD measure for the presented drop vertical jump that was quantified simultaneously with 3D motion analysis was 13.4 Nm of knee abduction load.

D. Example of representative subject whose combination of increased tibia length and mass associated with her rapid growth contribute to her increased risk to demonstrate high LOAD landing mechanics when using the clinic-based ACL injury risk prediction algorithm. Knee valgus motion during the drop vertical jump is calculated (X2− X1).

E. Knee flexion range of ROM during the drop vertical jump is calculated (ϴ1−ϴ2).

F. Completed nomogram for the representative subject (Tibia length: 45 cm; Knee valgus motion: 3.0 cm; Knee flexion ROM: 60.0°; mass: 71 kg; QuadHam: 1.19). Based on her demonstrated measurements this subject would have a 91% (116.5 points) percent chance to demonstrate high LOAD during the drop vertical jump. Her actual LOAD measure for the presented drop vertical jump that was quantified simultaneously with 3D motion analysis was 48.5 Nm of knee abduction load.