Bovine Hindlimb - Anatomy & Physiology
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Pelvic Girdle and Hip
Bones
The pelvic girdle is formed by two hip bones which are joined ventrally at the cartilagenous pelvic symphysis and articulate dorsally with the sacrum. The three components of each hip bone are the Ilium, pubis and ischium.
The bone that articulates with the hip bones to form the hip joint is the Femur.
Bovine Bone Specifics
- Ilium
- In the cow the tuber coxae is visible and is readily palpable.
- The sacral tuber has two prominences; the cranial and caudal dorsal iliac spines.
- The iliac crest is thin and concave.
- The ileal wing is orientated in a vertical manner.
- Ischium
- The ischial tuberosity is triangular in shape.
- Femur
- The greater trochanter extends further dorsally compared to the femoral head.
- The medial and lateral condylar ridges are very assymetrical with the medial ridge being larger.
Joints and Synovial Structures
Sacroiliac Joint
- In cattle the short branch of the dorsal sacroiliac ligaments connects the sacral tuberosity to the spinous processes of the sacrum.
- The sacrotuberous ligament is a broad sheet-like ligament, which extends between the lateral aspect of the sacrum and the dorsal border of ischium and ilium. In this ligament are the lesser and greater ischiatic foramen, these are present to allow for blood vessels, nerves and tendons. The caudal border of this ligament is visible subcutaneously.
Coxafemoral/Hip Joint
- The cow has the most limited range of movement compared other domestic species in its hip. This is mainly restricted to flexion and extension and is a result of the conformation of its femoral head, intraarticular ligaments and a large muscle mass around the joint.
- Cattle also have an extra acetabular notch on it's cranioventral aspect.
Musculature
The muscles affecting the pelvic girdle and hip can be divided into two distinct groups:
- Girdle Musculature
- Psoas minor - the muscle is marked by many tendinous intersections
- Iliac muscle - a fleshy muscle that is cross-sectionally flat cranially and round caudally. It originates from two heads; a strong lateral head from the wing of the ilium and a small medial one from the ileal shaft. They enclose the greater psoas and will unite to form a common tendon for insertion.
- Quadrate Lumbar - a thin tendinous muscle whose origin is at the proximal end of the last rib and the transverse process of the cranial lumbar vertebrae. Its insertion is the transverse processes of the caudal lumbar vertebrae and the sacral wing.
- Rump Muscles
- Superficial gluteal
- It is totally fused with the biceps muscle of the thigh forming the gluteobiceps.
- Middle Gluteal
- Origin - the gluteal surface of the ilium. The muscle is flat at its origin and so the iliac crest is very palpable.
- Insertion - The short portion inserts on the greater trochanter, the deep portion inserts on both the greater trochanter and distal and medial to it.
- Deep Gluteal
- Insertion - distal to the greater trochanter on the craniolateral aspect of the femur.
- Tensor Muscle of the Fascia Lata
- Origin - coxal tuberosity
- Insertion - it joins the fascia lata and so indirectly attaches to the patella, lateral pattelar ligament and cranial border of the tibia. A caudodorsal detachment joins the superficial gluteal and so attaches to the greater trochanter.
- Gluteobiceps
- Origin - Vertebral head - caudal sacral vertebrae, sacrotuberous ligament and ischial tuberosity. Pelvic head - venterolateral aspect of the ischium from the ischiatic tuberosity to the obturator foramen.
- Insertion - the two bellies unite and the redivide at mid-tibia level. The cranial belly attaches to the fascia lata and crural fascia and so inserts on the patella, the lateral patellar ligament and the tibial tuberosity. The cranial part forms the tarsal tendon and so inserts on the calcaneal tuberosity.
- A synovial bursa exists between the tarsal tendon and lateral femoral condyle.
- Semitendinous
- Origin - caudoventral aspect of the ischial tuberosity.
- Insertion - via a flat aponeurotic tendon to the cranial border of the proximal tibia, the crural fascia and the tendinous insertion of the gracilis muscle. An accessory tendon also inserts on the calcaneal tendon.
- Semimembranous
- Origin - it just has one from the pelvic head.
- Sartorius
- Origin - It is divided briefly into two head because of the passage of femoral vessels.
- External Obturator
- Cattle have an extra intrapelvic part that originates from the ilial body, the pubis and ischium. This then inserts with the rest of the muscle on the trochantic fossa.
- Superficial gluteal
Proximal Hindlimb including Stifle and Tarsus
Bones
The bones immediately distal to the femur are the tibia, fibula, patella and some minor sesamoid bones. Some of these are involved in the stifle joint, weight-bearing and providing attachment for muscles.
Distal to these bones are the complex series of bones that make up the tarsus, these are the tarsal bones and metatarsals.
Bovine Bone Specifics
- Patella
- The patella is extended medially by fibrocartilage.
- Fibula
- The shaft of the fibula is totally absent.
- The proximal head is fused to the tibia.
- The distal part remains as the malleolar bone, which articulates with the tibia.
- Talus
- The trochlear ridges lie in a sagittal direction and articulates with the medial malleolus medially and the mlleolar bone laterally.
- The distal trochlear is well defined, articulating with the combined 4th and central tarsal bones.
- Calcaneus
- The calcaneal tuberosity's proximal aspect is roughened and hollowed out.
- Distal Row of Tarsal Bones
- The cow only has three bones in the distal row, with the 1st tarsal bone being the only one left unfused. The 2nd and 3rd tarsal bones are fused together. The central and 4th tarsal bones are also fused.
Joints and Synovial Structures
- Like the horse the cow has three patellar ligaments; the middle patellar ligament, the lateral patellar ligament and the medial patellar ligament.
- The middle patellar ligament connects the the cranial aspect of the patella apex to the tibial tuberosity. It has one associated bursae; one between the ligament and the groove on the tibial tuberosity. It is palpable just proximal to the tibial plateau.
- The medial patellar ligament connects the parapatellar fibrocartilage to the medial aspect of the tibial tuberosity.
- The lateral patellar ligament the cranio-lateral aspect of the patella to the lateral aspect of the tibial tuberosity.
- The medial and lateral femorotibial joint capsules communicate and the medial femorotibial communicates with the femoropatellar.
- The cow has some degree of flexion and extension in its proximal intertarsal joint.
- Like the dog the cow has an extra branch to its short medial collateral ligament that extends to the medial metatarsal bones.