Muscles classification according to fibers arrangement of muscle and on the basis of muscle function in body
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Shazia rehman CLASSIFICATION OF MUSCLES
CLASSIFICATION OF MUSCLES On the basis of muscles fiber arrangement Parallel fasciculi Oblique fasciculi Circular fasciculi Spiral fasciculi Cruciate fasciculi On the basis of functions Agonists Antagonists Synergists Fixators
On the basis of muscles fiber arrangement Skelton muscle is made up of fascicles(bundle of muscle fibres).The arrangement of fascicles vary, resulting in muscle with different shapes & function capabilities
Parallel fasciculi Parallel muscles have fibres which, as the name suggests , run parallel to line of pull . Great range of movement Less Strength Strap Muscles Quadrilateral Muscles Fusiform Muscles
Fusiform Muscles Spindle-shaped, with the muscle belly being wider than the origin and insertion
Strap Muscles Length is greater then width giving them strap like appearance Eg sternohyoid muscle
Quadrilateral Muscles Length is short giving muscle a flat, quadrilateral appearance Eg Thyrohyoid muscle
Oblique fasciculi Muscle fibre arrange oblique to line of pull Greater strength Less range of movement Triangular muscles Radial Muscles Pennate Muscles
Triangular muscles A flat muscle with a broad origin and narrow insertion Eg Deltoid Muscle
Radial Muscles Muscle fibres converge into central tendon from all sides. Also called circumpenate Muscle
Pennate Muscles Pennate muscles have a large number of muscle fibres per unit and so are very strong , but tire easily. They can be divided into: Unipennate Bipennate Multipennate
Unipennate All muscle fibres are arrange obliquely on one side of tendon E.g flexor pollicis longus
Bipennate All muscle fibres are arrange obliquely on both side centrally placed tendon. E.G Rectus femoris muscle of thigh
Multipennate Multipennate muscles have multiple rows of fibres, with a central tendon E.G Deltoid muscle
Circular fasciculi These muscles appear circular in shape and are normally sphincter muscles which surround an opening such as the mouth. E.G Obicularis Oris Obicularis Oculi
Spiral fasciculi Muscle fibres are twisted in arrangement close to their insertion. Also called twisted Muscle E.G Pectoral Major muscle
Cruciate fasciculi A muscle in which the fiber bundles are arranged in the shape of an X . E.g. Sternocleidomastoid muscle
ON THE BASIS OF FUNCTION When completing movements such as walking or squatting, there are a lot of different muscles involved in order to complete the movement smoothly and effectively. They achieve this as they each adopted the appropriate type of contraction (concentric, eccentric or isometric) and have their own specific role that they play during the movement.
There are four different roles that a muscle can fulfill during movement, these roles are : Agonist Muscle Antagonist Muscle Synergist Muscle Fixators Muscle
Agonist Muscle The agonist in a movement is the muscle that provides the major force to complete the movement(prime movers). In the bicep curl which produces flexion at the elbow, the biceps muscle is the agonist
Antagonist Muscle The antagonist in a movement refers to the muscles that oppose the agonist. During elbow flexion where the bicep is the agonist, the tricep muscle is the antagonist. While the agonist contracts causing the movement to occur, the antagonist typically relaxes
Synergist The synergist in a movement is the muscle that stabilizes a joint around which movement is occurring, which in turn helps the agonist function effectively. Synergist muscles also help to create the movement. In the bicep curl the synergist muscles are the brachioradialis and brachialis which assist the biceps to create the movement and stabilize the elbow joint .
Fixator The fixator in a movement is the muscle that stabilizes the origin of the agonist and the joint that the origin spans (moves over) in order to help the agonist function most effectively . In the bicep curl this would be the rotator cuff muscles will be guardians of the shoulder joint ’