Figure 3

Position of the muscle motor points for the quadriceps and gastrocnemii in 53 healthy subjects. The arrows indicate the average motor point (MP) positions along the respective reference lines. A) Vastus lateralis muscle MPs (blue circles, proximal MP; white circles, central MP; yellow circles, distal MP). The continuous black line is the reference line for the proximal MP, while the dashed black line is the reference line for the central and distal MPs. B) Rectus femoris muscle MPs (blue circles, proximal MP; yellow circles, distal MP). C) Vastus medialis muscle MPs (blue circles, proximal MP; yellow circles, distal MP). The continuous black line is the reference line for the proximal MP, while the dashed black line is the reference line for the distal MP. D) Medial (blue circles) and lateral (yellow circles) gastrocnemii muscle MPs. (Modified from Botter et al. [5]. Copyright © 2011 Springer. Used with permission provided by Copyright Clearance Center, license number: 2923641294715).