Intrinsic Musculature of the Pelvic Limb Anatomy II PDF

Intrinsic musculature of the Pelvic Limb By Dr. Anas Al Makhzoomi  The intrinsic muscles of the hindlimb The power developed by these muscles is transferred to the trunk through the coxofemoral or hip joint and sacroiliac joints, which are supported by the muscle...

Intrinsic musculature of the Pelvic Limb By Dr. Anas Al Makhzoomi  The intrinsic muscles of the hindlimb The power developed by these muscles is transferred to the trunk through the coxofemoral or hip joint and sacroiliac joints, which are supported by the muscles of the hindlimb. The intrinsic musculature comprises: muscles of the hip muscles of the stifle muscles of the tarsus muscles of the digits  Muscles of the hip Rump muscles :The lateral Muscle of the Pelvis: They extend between the ilium and the thigh and are arranged in several layers Caudal muscles of the thigh : The hamstring group of muscles, they extend from the ischium to the tibia, and their tendinous components continue as part of the common calcaneal tendon to the calcaneus. Muscles of the hip Medial muscles of the thigh : They extend between the pelvic floor and the femur on the medial side of the thigh Inner pelvic muscles: They extend between the pelvis and the trochanteric fossa of the femur  Rump muscles : The lateral Muscle of the Pelvis Tensor fascia lata muscle ORIGIN: The tuber coxae and adjacent part of the ilium; the aponeurosis of the middle gluteal muscle. INSERTION: The fascia lata. ACTION: Draws limb forwards, tensor of the fascia. Superficial gluteal muscle ORIGIN: The lateral border of the sacrum , first caudal vertebra, partly by means of the sacrotuberous ligament, the cranial dorsal iliac spine by means of the deep gluteal fascia. INSERTION: The third trochanter. ACTION: Extensor and flexor of the hip joint Middle gluteal muscle ORIGIN : The crest and gluteal surface of the ilium. INSERTION: The greater trochanter. ACTION: Extensor of the hip joint, draws limb outwards and backwards  Rump muscles : The lateral Muscle of the Pelvis Deep gluteal muscle : ORIGIN: from the lateral surface of the ilial shaft, near the iliac spine, INSERTION: The cranial aspect of the greater trochanter. ACTION: Draws limb outwards and backwards Piriform muscle : It is the deep caudal portion of the middle gluteal is readily separated from the main muscle mass and it is covered by the superficial gluteal muscle ORIGIN: last sacral vertebra and the sacrotuberous ligament INSERTION: distally to the greater trochanter on the lateral surface of the femur. ACTION: Draws limb outwards and backwards Inner pelvic muscles External obturator muscle ORIGIN : Outer surface of the obturator foramen INSERTION: The trochanteric fossa. ACTION: Draws hindlimb outwards Quadratus femoris ORIGIN : The ventral surface of the caudal part of the ischium. INSERTION: Intertrochanteric crest. ACTION: Draws hindlimb outwards Inner pelvic muscles Internal obturator muscle ORIGIN : Inner surface of the obturator foramen INSERTION: The trochanteric fossa of the femur. ACTION: Draws hindlimb outwards Gemellus muscles ORIGIN: The lateral surface of the ischium, caudal to the acetabulum and ventral to the lesser ischiatic notch. INSERTION: The trochanteric fossa. ACTION: Draws hindlimb outwards  Cranial Muscles of the Thigh Quadriceps Femoris : is divided into four heads of origin, which are fused distally ORIGIN : from the femur and the ilium INSERTION: the tibial tuberosity. ACTION: most powerful extensor of the stifle joint and is necessary for the animal to support its weight. Patella a sesamoid bone, is intercalated in the large tendon of insertion of the quadriceps. It articulates with the trochlea of the femur. Patellar Ligament extends from the patella to the tibial tuberosity. It is the tendon of insertion of the quadriceps femoris Cranial Muscles of the Thigh  The rectus femoris :The straight muscle of the thigh ORIGIN : ilium, cranial to the acetabulum INSERTION: Patella, tibial tuberosity ACTION: Extensor of the stifle joint; flexor of the hip joint  The vastus lateralis : lies lateral and caudal to the rectus femoris, to which it is fused distally. ORIGIN : Lateral surface of femur INSERTION: Patella, tibial tuberosity ACTION: Extensor of the stifle joint  The vastus intermedius : lies directly on the smooth cranial surface of the femur and is quite intimately fused with the other two vasti. ORIGIN : Medial surface of femur INSERTION: Patella, tibial tuberosity ACTION: Extensor of the stifle joint Cranial Muscles of the Thigh The vastus medialis : arises from the medial side of the proximal end of the cranial surface of the femur and the proximal end of the medial lip of the caudal rough surface. ORIGIN : Medial surface of femur INSERTION: Patella, tibial tuberosity ACTION: Extensor of the stifle joint Caudal muscles of the thigh This group consists of three primary muscles: Biceps femoris m : laterally Semitendinous m: caudally Semimembranou s m: medially Caudal muscles of the thigh Biceps femoris : ORIGIN : The sacrotuberous ligament and the ischiatic tuberosity. INSERTION : by means of fascia lata and crural fascia to : The patella, patellar ligament, cranial border of the tibia by means of the crural fascia to : The subcutaneous part of the tibial body; the tuber calcanei ACTION : extends hip and hock; its cranial part extends, caudal part flexes stifle The lymph node lying in the fat Caudally, a strand of heavy fascia at runs to the tuber calcanei and its caudal border directly caudal helps to form the common Caudal muscles of the thigh Semitendinous: ORIGIN: The ischiatic tuberosity INSERTION: The distocranial border of the tibia. The medial surface of the body of the tibia and the tuber calcanei by means of the crural fascia. ACTION : Flexor of the stifle joint; extensor of the hip joint Caudal muscles of the thigh Semimembranosus: ORIGIN : The ischiatic tuberosity INSERTION : The distal medial lip of the caudal rough surface of the femur The medial condyle of the tibia. ACTION : Extensor of the stifle joint; draws limb inwards Medial muscles of the thigh This group consists of four primary muscles: Sartorius muscle Gracilis muscle Pectineal muscle Adductor muscles Medial muscles of the thigh Sartorius muscle ORIGIN: Cranial part—the crest of the ilium and the thoracolumbar fascia caudal part—the cranial ventral iliac spine and the adjacent ventral border of the ilium. INSERTION: Cranial part—the patella, in common with the rectus femoris of the quadriceps caudal part—the cranial border of the tibia, in common with the gracilis ACTION: Adducts and draws hindlimb forwards Medial muscles of the thigh Gracilis muscle ORIGIN: Aponeurosis on the symphysis INSERTION: The cranial border of the tibia and, with the biceps femoris and semitendinosus, the tuber calcanei ACTION: adducts hindlimb Medial muscles of the thigh Pectineus muscle ORIGIN: From the iliopubic eminence and the pubic tubercle via the prepubic tendon. INSERTION : The distal end of the medial lip of the caudal rough face of the femur. ACTION: adduction of thigh Medial muscles of the thigh Adductor muscles ORIGIN: The entire pelvic symphysis by means of the symphysial tendon, the adjacent part of the ischiatic arch, and the ventral surface of the pubis and ischium. INSERTION: Medial border of the femur ACTION: adducts hindlimb Muscles of The Crus The muscles of the crus comprise extensors and flexors of the tarsus and extensors and flexors of the digit. They are grouped in two masses according to the location of their bellies: one on the craniolateral aspect of the tibia, (Craniolateral group). the other one on the caudal aspect of the tibia, (Caudal groups). Craniolateral muscles of the crus This group can be divided into: Flexors of the tarsus with: Cranial tibial muscle (m. tibialis cranialis) Long fibular muscle (m. fibularis longus) Short fibular muscle (m. fibularis brevis) (Only presents in dogs) Third fibular muscle (m. fibularis tertius). (not present in dogs) Craniolateral muscles of the crus Flexors of the tarsus : Cranial tibial muscle ORIGIN: The extensor groove and the adjacent articular margin of the tibia; the lateral edge of the cranial tibial border. INSERTION: The plantar surface of the base of metatarsals I and II. ACTION: Flexor of tarsus Craniolateral muscles of the crus Fibularis longus muscle ORIGIN: The lateral condyle of the tibia, the proximal end of the fibula, and the lateral epicondyle of the femur by means of the lateral collateral ligament of the stifle. INSERTION: The fourth tarsal bone; the plantar aspect of the base of the metatarsals. ACTION : Flexor of tarsus, draws limb inwards Craniolateral muscles of the crus Extensors of the digits with:  long digital extensor muscle  lateral digital extensor muscle  long extensor muscle of first digit Craniolateral muscles of the crus Long digital extensor muscle ORIGIN: The extensor fossa of the femur. INSERTION: The extensor processes of the distal phalanges of digits II, III, IV, and V. ACTION : Extensor of the digits, extensor of stifle joint In the distal crus it runs under the crural extensor retinaculum along with the cranial tibial tendon. they are surrounded by a synovial sheath and are held in place by the tarsal extensor retinaculum Craniolateral muscles of the crus lateral digital extensor muscle ORIGIN : Fibula and lateral condyle of tibia INSERTION : Middle phalanx of 5th or 4th digit ACTION : Extensor of the digits Craniolateral muscles of the crus long extensor muscle of first digit ORIGIN : Fibula INSERTION : 2nd digit ACTION : Extensor of the 2nd digit Caudal Muscles of the crus Gastrocnemius muscle ORIGIN: The medial and lateral supracondylar tuberosities of the femur. INSERTION: The proximal surface of the tuber calcanei. contribute the major component of the common calcanean tendon. ACTION : Extensor of the tarsus; flexor of the stifle joint Caudal Muscles of the leg the crus Superficial digital flexor muscle ORIGIN: The lateral supracondylar tuberosity of the femur. INSERTION: The tuber calcanei and the bases of the middle phalanges of digits II, III, IV, and V. ACTION : Flexor of the stifle joint; flexor of the digits; extensor of the tarsus  Caudal Muscles of the leg the crus Deep digital flexor muscle consists of three separate heads: Caudal tibial muscle lateral digital flexor muscle Medial digital flexor muscle ORIGIN: The caudal aspect of the proximal two thirds of the tibia, the proximal half of the fibula, and the adjacent interosseous membrane. INSERTION: The flexor tubercle on the plantar surface of the base of each of the distal phalanges. ACTION : Flexor of the digits  Caudal Muscles of the leg the crus Popliteus muscle ORIGIN: The lateral epicondyle of the femur. INSERTION: The proximal third of the caudal surface of the tibia. ACTION : Flexor of the stifle joint; draws limb inwards It courses caudally, medial to the lateral collateral ligament. At the junction of the tendon with the muscle, there is a sesamoid that articulates with the caudal aspect of the lateral condyle of the tibia.