Limb Movement Flashcards
Hyperextension
When a joint goes beyond its normal RoM
Palmar
Forelimb fetlock
Planter
Hindlimb fetlock
Flexion
Size of angle formed is nearly always reduced
Extension
Increasing the size of an angle between bones
Protraction
Forward movement of entire limb in relation to trunk (only bears weight when moving backwards)
How is forelimb protraction brought about?
Muscle contraction and release of energy stored in elastic tissue in stance phase
Primary muscles used in forelimb protraction
Brachiocephalicus
Omotransversarius
These muscles have long fascicles that facilitate long ranges of movement (Payne et al., 2005).
Main elastic elements used in forelimb protraction
Lacertus fibrosus and its tendinous continuation through the belly of biceps brachii
Use of trapezius (pars cervicalis) in forelimb protraction
Pulls scapula forward over the lateral aspect of the thorax (if the limb is seen as having a fixed axis
of rotation roughly on a level with the shoulder joint then this muscle would rotate the limb about
this axis and cause retraction, at least of the part of the limb distal to the point of rotation)
Intrinsic muscles used in forelimb protraction
Biceps brachii
Extensor carpi radialis
Extensor digitorum communis
Main protractors of the hindlimb
Gluteus superficialis
Tensor fasciae latae
Psoas major
Iliacus
Intrinsic muscles used in hindlimb protraction
Rectus femoris
Flexors of the hock (e.g. tibialis cranialis)
Extensors of the digit (e.g. extensor digitorum longus)
What ensures the hind hoof clears the ground during swing phase?
Reciprocal apparatus ensure the hock is flexed, this then extends the hock at the end of the phase in order to meet the required length of the stride
Retraction
Backward movement of the entire limb in relation to the trunk
Primary muscles used in forelimb retraction
Latissimus dorsi
Ascending part of pectoral muscle
Trapezius, serratus ventralis and rhomboideus have fibres arranged in a fan, in which some of assist in retraction
Retraction of the forelimb in stance phase
Elbow remains extended, which is achieved mostly by the contraction of the triceps bracii
Muscles used in hindlimb retraction
Middle gluteal muscle Hamstring muscles (biceps femoris, semitendinosus, semimenbranosus)
Abduction
Movement of the limb away from the median plane (e.g. cow kicking)
Only possible in shoulder and hip (ball and socket joints)
Muscles used in forelimb abduction
Trapezius
Rhomboideus
Infraspinatus
Deltoideus
Muscles used in hindlimb abduction
Gluteal muscle group
Biceps femoris
Tensor fasciae latae
Adduction
Movement of the limb towards the median plane (e.g. half pass)
Muscles used in forelimb adduction
Subscapularis
Teres major
Coracobrachialis
Pectoral muscles including subclavius
Muscles used in hindlimb adduction
Adductor Iliacus Psoas major Semimembranosus Semitendinosus Sartorius Gracilis
Circumduction
When the hoof traces and arc as it moves forward (paddling or winging)
Made up from a combination of protraction and abduction
Pronation
Entire limb rotated inward
Supination
Outward rotation of the limb
Muscles used in forelimb pronation
Subscapularis
Teres major
Brachiocephalicus
Muscles used in inward rotation of hindlimb
Tensor fasciae latae
Gluteus superficialis
Semimembranosus
Gluteus profundus
Muscles used in outward rotation of forelimb
Infraspinatus
Teres minor
Deltoideus
Muscles used in outward rotation of hindlimb
Iliacus
Sartorius
Psoas major
Several small muscles immediately behind the femoral head
