There is also a much smaller second extensor on the outer side of this in each limb, the lateral extensor of the phalanges.
In the fore-leg the tendon of this muscle (which corresponds with the extensor minimi digiti of man) receives a slip from that of the principal extensor, and is inserted into the first phalanx.
There is a patella, intercalated in the tendon of the femori-tibialis or extensor cruris muscle.
On the anterior or extensor surface of the limb a powerful tendon (7 in fig.
A strong ligamentous band behind the metapodium, arising from near the upper extremity of its posterior surface, divides into two at its lower end, and each division, being first connected with one of the paired upper sesamoid bones, passes by the side of the first phalanx to join the extensor tendon of the phalanges.
Consequently only a few of the original extensor muscles have been preserved, but these are much modified into very independent organs, notably the extensor metacarpi radialis longus, the ext.
It is a brief extension of the limb at the knee-joint, due to a simple contraction of the extensor muscle, elicited by a tap or other short mechanical stimulus applied to the muscle fibres through the tendon of the muscle.
This runs down the anterior and outer side of the upper arm, and is attached to the proximal tendon of the extensor metacarpi radialis longus, a little below the outer condyle of the humerus.
On the anterior side of the tibia, is the intercondylar sulcus, which is crossed by an oblique bridge of tendon or bone, acting as a pulley for the tendon of the extensor digitorum communis muscle.
The motor cells of the extensor muscles, when preoccupied by cerebral influence, appear refractory.