Locomotor Flashcards
Describe the anatomy of the femur? (5)
Diaphysis - shaft. Epiphysis - around the growth plate. Head Metaphysis - growth plate. Trochanter.
What is abduction? (1)
Movement away from the midline.
What is adduction? (1)
Movement towards the midline.
Define cranial translation of the proximal tibia. (1)
Sliding movement in a cranial direction.
Define valgus deviation of the carpus. (1)
Lateral deviation, refers to distal limb only.
Define varus deviation of the stifle/knee. (1)
Medial deviation of the distal limb.
Define dorsal (sub)luxation of the femoral head. (1)
Separation of joint surfaces, i.e. dislocation.
How do levers change the force required to move a set mass? (2)
Altering the length of the lever arms to reduce load or increase speed.
Outline the terminology for levers. (4)
Lever - rigid bar (bone).
Fulcrum - pivot point (joint).
Load - the mass that requires moving (limb/bodyweight).
Effort/force - force input to generate movement (muscle).
What is a type 1 lever? Give an example. (2)
See-saw, effort and load in opposite directions, fulcrum in the centre. E.g. elbow.
What is a type II lever? Give an example. (2)
Wheelbarrow, effort and load run in the same direction, fulcrum at one end. E.g. dog standing up, pivots on toes. load close to the fulcrum.
What is a type III lever? Give an example. (2)
Most levers are of this type. Baseball swing, effort and load in the same direction, effort close to the fulcrum.
Describe the hierarchical structure of skeletal muscle. (4)
Myofibrils
What is the function of a tendon? (1)
Join muscle bellies to bones or other tendons.
What is the function of a ligament? (1)
Join bone to bone.
What is the origin of a muscle? (1)
Less movable attachment, typically proximal.
What is the insertion of a muscle? (1)
Mobile segment of the body with attachment - typically distal.
What is Wolff’s law? (1)
Every change in the function of a bone is followed by a certain definite change in it’s internal architecture and it’s external conformation.
The bone’s shape is a result of the functional forces experienced through life optimising the architecture to resist failure/fracture.
What is the name of the type of joint between the quadruped forelimb and the thorax. (3)
Synsarcosis. There is no bony attachment to the trunk, as a result there is a greater possible range of motion with the attachments made from purely muscular and connective tissue.
What is the function of the olecranon? (1)
Attaches the insertion of the triceps brachii, allows extension of the elbow.
What are the functions of the collateral ligaments? (3)
Connects the lateral epicondyle to the lateral radial head and lateral ulna.
Connects the medial epicondyle to the medial radial head.
Prevents lateral or medial translation.
What is the annular ligament? (1)
Encircles the head of the radius and attaches it to the ulna notch either side.
What is the function of the radius? (1)
Bears most of the weight.
What is the function of the ulna? (1)
Provides rotational and joint stability.
Describe the anatomy of the radius and ulna. What is the clinical relevance of this? (4)
There is a strong fibrous attachment between radius and ulna that allows rotation.
The radius has a proximal and distal growth plate for longitudinal lengthening.
The ulna only has a growth plate at the distal end of the bone.
This can make for discrepancies in the length between radius and ulna, known as joint incongruity.
Why is the medial coronoid process prone to problems in dogs? (1)
Most common cause of lameness, due to un-equal load sharing between radius and ulna due to joint incongruity.
Describe the anatomy of the carpus? (4)
Collateral ligaments prevent lateral and medial translation.
Short dorsal carpal ligaments hold together the carpal bones.
Distal accessory carpal ligament connects accessory carpal bone to the metacarpals.
Palmar carpal ligament connects the accessory carpal bone to the ulnaris lateralis and FCU tendon.
What are extrinsic muscles of the forelimb? (1)
Muscles which attach from the limb to the body.
What are the intrinsic muscles of the forelimb? (1)
Muscles that have both origin and insertion within the limb.
What is the function of the trapezius muscle? (1)
Attaches the dorsal scapula to the trunk. Allows elevation of the limb and some protraction (cervical) and retraction (thoracic).
What muscles are involved primarily in the thoracic girdle? (4)
Major muscles: Pectorals (deep and superficial), serratus ventralis and rhomboideus.
Minor: other extrinsic muscles. Trapezius, latissimus dorsi, omotransversarius, brachiocephalicus.
What is the function of the brachiocephalicus? (1)
Protracts the limb.
What are the purposes of the muscles of the thoracic girdle? (3)
Serratus ventralis - suspends the thorax.
Pectorals - adduction and support.
Rhomboideus - suppot, elevates the limb, abducts the limb by moving the proximal scapula medially.
What is the function of the latissimus dorsi? (1)
Retracts the limb.
Where does the trapezius attach? What is it’s fibre direction? (2)
The trapezius has two bellies, it attaches from the scapular spine to the cervical midline cranially and the dorsal midline caudally. The fibres are caudo-ventral in the cervical portion, and cranio-ventral in the thoracic portion.
Where does the omotransversarius attach? (1)
From the distal scapular spine to the transverse process of C1-2.
Describe the anatomy of the brachiocephalicus. (1)
Two portions, the cleidobrachialis and the cleidocephalicus.
Describe the anatomy of the latissimus dorsi. (1)
Large fan shaped muscle from the teres major tuberosity on the caudal humerus to the thoracolumbar fascia and the last 2-3 ribs.
Describe the location of the superficial pectorals. (1)
First 2-3 sternebrae to the greater tubercle.
Describe the location of the deep pectorals. (1)
Whole sternum to the lesser tubercle and the brachial fascia.
Describe the intrinsic shoulder muscles. (4)
Supraspinatus - supraspinous fossa to the greater tubercle. Shoulder extensor. Innervated by the suprascapular nerve.
Infraspinatus - infraspinous fossa to the lateral greater tubercle, offers lateral support. Innervated by the suprascapular nerve.
Describe the shoulder flexor muscles. (4)
Deltoideus - lateral, acromion and scapula spine to the deltoid tuberosity. Innervated by the axillary nerve.
Teres Major - medial, caudal scapula margin to the medial humeral diaphysis. Innervated by the axillary nerve.