Effect of load on rotational moment of inertia
. | . | Site of load . | . | . | ||
---|---|---|---|---|---|---|
Joint . | Unloaded . | Proximal femur . | Distal femur . | Distal tibia . | ||
Thorax-coxa | 38962 | 43289 (1.1) | 103265 (2.7) | 247260 (6.4) | ||
Coxa-trochanter | 27176 | 27744 (1.0) | 73184 (2.7) | 197860 (7.3) | ||
Femur-tibia | 4846 | 56108 (11.6) |
. | . | Site of load . | . | . | ||
---|---|---|---|---|---|---|
Joint . | Unloaded . | Proximal femur . | Distal femur . | Distal tibia . | ||
Thorax-coxa | 38962 | 43289 (1.1) | 103265 (2.7) | 247260 (6.4) | ||
Coxa-trochanter | 27176 | 27744 (1.0) | 73184 (2.7) | 197860 (7.3) | ||
Femur-tibia | 4846 | 56108 (11.6) |
Values are mg mm2 (N=5 animals)
Numbers in parentheses indicate the factor of increase in rotational inertia caused by each load. The basis of the calculation is as follows: Coxa:mass 7.8 mg, length 3.6 mm, centre of mass 1.8 mm. Femur: 107.8 mg, 20.0 mm,7.3 mm. Tibia: 19.0 mg, 21.0 mm, 12.6 mm. Tarsus: 3.3 mg, 6.8 mm, 3.4 mm. Load: 142 mg, centred 2 mm from end of limb segments. Leg posture: thorax-coxa joint angle 11.8°, coxa-trochanter joint angle 27.8°, femur-tibia joint angle 125.2°, tibia-tarsus joint angle 45.2° (all as required to reach the mean position of the posterior stimulus site)