Anatomy of the Cat

by Jacob Reighard; H. S. Jennings

Origin ([Fig. 90], 2).—From the ventral surface of the tuberosity of the ischium by tendon- and muscle-fibres. The fibres diverge, and near the knee the mass has spread out, ending in a fascia. The dorsal border of the muscle and the common fascia are continuous dorsad with the superficial fascia of the thigh and with the tendon of the caudofemoralis ([Fig. 68], s). Ventrad it is continuous with the superficial fascia of the shank.

Insertion into rather more than the proximal one-third of the dorsal border of the tibia along its lateral margin and into the lateral margin of the patella. In passing over the knee-joint it is closely united to the underlying ligaments and tendons.

Relations.—Outer surface with the superficial fascia and with a few of the most caudal fibres of the cutaneus maximus ([Fig. 62], b, [page 94]). Cranial (or dorsal) edge with the caudofemoralis ([Fig. 68], s) and the vastus lateralis ([Fig. 90], d). Caudal border with the semitendinosus ([Fig. 68], u) and a mass of fat. Inner surface with the caudofemoralis ([Fig. 68], s), the tenuissimus ([Fig. 90], g), the obturator internus ([Fig. 90], e), the quadratus femoris ([Fig. 90], f), the semitendinosus ([Fig. 68], u), the semimembranosus ([Fig. 90], i), the adductor femoris ([Fig. 90], h), the great sciatic nerve ([Fig. 163], a), and distad with the following muscles of the lower leg: the tibialis anterior ([Fig. 90], n), the extensor longus digitorum ([Fig. 90], p), the peroneus longus ([Fig. 90], q), and the lateral head of the gastrocnemius ([Fig. 90], m).

Action.—Abductor of the thigh, and flexor of the shank.

M. tenuissimus or M. abductor cruris ([Fig. 90], g).—A very slender muscle, only three or four millimeters wide.

Origin from the tip of the transverse process of the second caudal vertebra, in common with the caudofemoralis ([Fig. 68], s) or gluteus maximus. It passes obliquely beneath the biceps femoris ([Fig. 68], t) distad and ventrad, to the distal end of the ventral border of that muscle. Here it becomes continuous with the ventral border of the biceps, ending in a continuation of the same fascia into which the biceps is inserted.

Relations.—Outer surface with the caudofemoralis ([Fig. 68], s) and the biceps femoris ([Fig. 68], t); distad with the integument. Inner surface with the obturator internus ([Fig. 90], e), quadratus femoris (f), semitendinosus (j), adductor femoris (h), semimembranosus (i), and distad with the muscles of the lower leg.

M. caudofemoralis (parameralis, Strauss-Durckheim) ([Fig. 68], s, [page 117]).

Origin by a flat tendon from the transverse processes of the second and third caudal vertebræ. The muscle forms a flat band which passes distad along the middle of the lateral side of the thigh over the pelvis and caudad of the great trochanter. At the middle of the thigh it ends in a very thin tendon. The tendon passes distad along the medial surface of the biceps femoris ([Fig. 68], t), pierces the fascia lata near the knee, and passes to its

Insertion into the middle of the lateral border of the patella.