318 FASCL# AND MUSCLES OF THE HORSE 
fascia is very thick and strong on the front and lateral surface. This part, the 
fascia lata (Fig. 267), is continuous with the gluteal fascia; it is tendinous in char- 
acter, and easily separable from the underlying muscles. It furnishes insertion to 
the tensor fascize latee and to the biceps femoris (in part), by both of which it is 
tensed. At the stifle it is attached to the patella and the lateral and medial patellar 
ligaments. Medially it is continuous with the medial femoral fascia. It furnishes 
the following intermuscular septa: (1) One which passes between the vastus lat- 
eralis and biceps femoris to be attached to the third trochanter of the femur; (2) 
two which pass between the three branches of the biceps femoris; (3) a fourth be- 
tween the biceps femoris and semitendinosus. The medial femoral fascia (Fascia 
femoralis medialis) covers the superficial muscles on the medial surface of the thigh. 
At its upper part it is joined by the femoral lamina of the aponeurosis of the external 
oblique muscle (Fig. 575). The posterior part is thin. It is continuous with the 
fascia lata in front and the fascia cruris below. At the stifle it fuses with the ten- 
dons of the sartorius and gracilis. 
The fascia cruris, or fascia of the leg, consists of three layers. Two of these 
invest the entire region and may, therefore, be termed the common fasciz. The 
superficial layer is a continuation of that of the thigh, while the second layer may be 
regarded chiefly as a continuation of the tendons of the superficial muscles of the 
hip and thigh (biceps femoris, semitendinosus, tensor fascize late, sartorius, and 
gracilis). The two layers frequently fuse, and are attached chiefly to the medial 
and lateral patellar ligaments and the crest and medial surface of the tibia. About 
the middle of the leg the two layers unite behind the deep flexor of the digit and 
form a strong band which passes downward in front of the tendons of the gastroc- 
nemius and superficial flexor, to be attached with the latter to the anterior and 
medial part of the tuber calcis. This constitutes a tarsal tendon of insertion of the 
biceps femoris and semitendinosus. <A strong band, about two inches in width, 
arises from the lateral supracondyloid crest, descends over the lateral head of the 
gastrocnemius, and blends with the foregoing and the superficial flexor tendon. 
The third layer forms sheaths for the muscles, furnishing origin in part to their 
fibers. Two important intermuscular septa are detached, viz.: (1) One which 
passes between the long and lateral digital extensors to be attached to the fibula 
and the lateral border of the tibia; (2) one between the lateral digital extensor and 
the deep digital flexor. 
The tarsal fascia (Fascia tarsi) fuses with the igaments and bony prominences 
of the region. It is strong and tendinous in front, and joins the tendon of the long 
extensor below the joint. On the sides it is thin and fuses with the ligaments. 
Posteriorly it is very thick and strong, forming an annular ligament which stretches 
from the medial ligament to the fibular tarsal bone and the plantar ligament. This 
converts the groove at the back of the hock into a canal, in which are the deep flexor 
tendon with its synovial sheath and the plantar vessels and nerves. In this vicinity 
there are three annular ligaments (Ligamenta transversa). The proximal one binds 
down the tendons of the long extensor, peroneus tertius, and tibialis anterior on 
the distal end of the shaft of the tibia. The middle one stretches from the fibular 
tarsal bone to the lateral tendon of the peroneus tertius, forming a loop around the 
tendon of the long extensor. The distal band stretches across the proximal ex- 
tremity of the large metatarsal bone and incloses the tendons (and sheaths) of the 
two extensors of the digit. 
The metatarsal and digital fascia do not differ materially from those of the 
corresponding regions of the thoracic limb. 
