Muscles Of The Dog Forelimb Flashcards
Name the 8 extrinsic muscles of the forelimb
- Trapezius
- Rhomboideus
- Omotransversarius
- Serratus ventralis
- Latissimus dorsi
- brachiocephalicus
- superficial pectoral
- deep pectoral
What is the muscular attachment between the limb and trunk called in domestic species?
OMOTHORACIC junction and is a synsarcosis
Describe the origin ad insertion of the trapezium
Made up of 2 parts
Entire muscle originates from the median raphe of the neck (C3-T9) and inserts onto the scapula spine
PARTS OF THE ORIGIN AND INSERTION ARE BY WAY OF A APONEUROSIS
Describe the action and innervation of the trapezius muscle
Action- abducts and elevates the forelimb
Innervation-accessory nerve
Describe the origin and insertion of the latissimus dorsi
Originates from the thoracolumar fascia (spinous processes of the lumbar and T7/8)
Inserts on the teres major tuberosity of the humerus
Describe the action ad innervation of the latissimus dorsi
Action- retraction of the forelimb, flex the shoulder joint
Innervation by thoracodorsal nerve (C7,C8 AND T1)
Describe the origin and insertion of the omotransversarius
OMO=SHOULDER TRANSVERSE= PROCESS OF THE CERVICAL VERTEBRAE
Originates at he transverse process of the 1st cervical vertebrae ad inserts onto the distal part of the scapula spine and acromion
Describe the action and innervation of the omotransversarius
Action- protraction of the limb, flexes the back laterally
Innervation= accessory nerve
Describe the origin and innervation of the rhomboideus
Divided into 2 parts
STRONGER CERVICAL PART- originates from the median raphe of the neck and extends to the spinal processes of the first 3 thoracic vertebrae
THORACIC PART-originates from the spinous processes of the 4th to 7th thoracic vertebrae
Innervation- both parts insert on the dorsal border (BOTH MEDIALLY AD LATERALLY) of the scapula
Describe the action and innervation of the rhomboideus
Action- to elevate the limb ad to draw the scapula against the trunk
Innervation- cervical and thoracic nerves
Describe the origin and insertion of the serratus ventralis
Named after its serrated shape and ventral position
Originates from the transverse processes of the last 5 cervical vertebrae and the ventral part of the last 8 ribs. It inserts onto the faces serrata of the scapula
Describe the action and innervation of the serratus ventralis
Action- retractor/ protractor of the limb, support the limb and trunk,inspiration
Innervation- cervical nerves and long thoracic nerve
Describe the origin and innervation of the brachiocephalicus
Has 3 parts divided by the VESTIGIAL CLAVICLE
Proximal to the clavicle are the cleidomastoideus muscle from the neck and the cleidocervicalis from the neck
COLLECTIVELY, THESE 2 MUSCLES ARE CALLED THE CLEIDOCEPHALICUS and are innervated by the cervical and accessory nerves
Distal to the clavicle, cleidobranchialis runs to the humerus and is innervated by the axillary nerve
Describe the action of the brachiocephalicus
To protract the limb
Describe the origin and insertion of the superficial pectoral
Originates from the cranial end of the sternum to the third costal cartilage and inserts on the major tubercle of the humerus
Describe the action and innervation of the superficial pectoral
Action-adducts the limb
Innervation- cranial pectoral nerve
Describe the origin and insertion of the deep pectoral
LARGER OF THE 2 PECTORALS
Originates from the entire length of the sternum and inserts on the minor tubercle (lesser tubercle) of the humerus
Describe the action and innervation of the deep pectorals
Action-to advance the trunk onto the limb and retract and adduct the limb
Innervation- caudal pectoral nerve
Describe the origin and insertion of the deltoideus
Muscle comprises of 2 parts
THE SCAPULA PART ARISES FROM A WIDE APONEUROSIS ARISING FROM THE SPINE OF THE SCAPULA, COVERING INFRASPINATUS MUSCLE
Originates from the spine and acromial process of the scapula and inserts onto the deltoid tuberosity
Describe the action and innervation of the deltoideus muscle
Action is to flex the shoulder
Innervation by the axillary nerve
Describe the origin and insertion of the long head of the tricep
Origin=the caudal border of the scapula
Insertion=olecranon tuber
Describe the action and innervation of the long head of the tricep
Action= to extend the elbow and flex the shoulder Innervation= the radial nerve
Describe the origin and insertion of the lateral head of the tricep
Origin= the tricepital line of the humerus
Inserts on the olecranon tuber
Describe the action and innervation of the lateral head of the tricep
Action=to extend the elbow
Innervation= the radial nerve
Describe the origin and insertion of the accessory and medial head of the tricep. What is its action and innervation?
Origin= the proximal third of the humerus
Inserts on the olecranon tuber of the ulna
Action=extensor of the elbow
Innervation= radial nerve
Describe the origin and insertion of the supraspinatus muscle
SUPRA= SUPERIOR TO SPINATUS= SPINE
Origin= arises from and fills the supraspinous fossa Inserts= by way of a short tendon on the major tubercle of the humerus