Table 7.

Geometric parameters of 9 forelimb equivalent MTUs representing sagittal plane actions of the corresponding individual MTUs with the same actions at the joints.

Muscle	${\text{a}}_1$, cm	${\text{a}}_2$, cm	${\phi }_1$, rad	${\phi }_2$, rad	${\text{R}}_1$, cm	${\text{R}}_2$, cm
Shoulder protractor	5.64	0.795	−0.277	2.392	0.794	−
Shoulder retractor	5.08	1.67	0.128	0.595	0.184	−
Shoulder protractor - Elbow flexor	1.22	1.11	−1.969	−0.400	1.00	0.53
Shoulder retractor - Elbow extensor	1.02	1.49	−0.046	−2.832	0.44	1.19
Elbow extensor	6.00	0.56	0.155	−2.691	0.21	−
Elbow flexor	7.15	0.74	−0.070	0.899	0.32	−
Elbow flexor - Wrist dorsiflexor (OV) Elbow flexor - Wrist dorsiflexor (VI)	1.14 0.61	9.51 3.33	0.287 −1.531	0.065 0.126	0.54	0.35
Wrist plantarflexor (OV) Wrist plantarflexor (VI)	0.64 0.52	9.63 2.89	−0.047 1.282	−0.052 −0.163	0.27	−
Wrist dorsiflexor (OV) Wrist dorsiflexor (VI)	1.11 0.601	9.89 1.71	−0.571 −2.333	0.044 0.115	0.24	−

Note. The geometric parameters are explained in Fig. 2. The MTU paths of the Elbow flexor - Wrist dorsiflexor, Wrist plantarflexor, and Wrist dorsiflexor consist of two lines connected by a via point (designated by V). The first line connects the point of origin (O) with V, and the second line connects V with the point of insertion (I).