The infraspinatus and teres minor rotate the head of the humerus outward (external, or lateral, rotation); they also assist in carrying the arm backward. Insertion: (distal attachments) a. . An anterior view of the final rotator cuff muscle, the subscapularis. Insertion of pectoralis minor, origin of coracobrachialis, and origin of short head of Biceps; Question: 1. Origin of Supraspinatus muscle 3. Structure Origin Insertion Action Deltoideus, pars clavicularis Lateral third of clavicle Deltoid tuberosity of the lateral side of the body of the . Origin: Infraspinous fossa of scapula Insertion: Greater tubercle of humerus, posterior to insertion of supraspinatus Teres Minor (works with infraspinatus) Small, elongated muscle. Teres minor is part of the rotator cuff muscles . True Back Muscles Superficial/Deep Origin Insertion Action Splenius Capitis Superficial Contract one side, rotate head to . This video explains the anatomy of the infraspinatus muscle, one of the 4 rotator cuff muscles: origin, insertion and actions. The origin is the attachment of the muscle to the least mobile of the two bones involved in an action or movement. Its synergists are teres minor and the deltoid. The supraspinatus (plural supraspinati) is a relatively small muscle of the upper back that runs from the supraspinous fossa superior portion of the scapula (shoulder blade) to the greater tubercle of the humerus.It is one of the four rotator cuff muscles and also abducts the arm at the shoulder. rami of cervical spinal nerves 1-4. action: retracts (adducts) and depresses. Action: Outward rotator and abductor of the humerus and a flexor or extensor of the shoulder joint, depending on the position of the joint when the muscle contracts. action: extension, horizontal extension and lateral rotation of humerus at the shoulder joint. It helps in extending shoulders and with the help of other rotator cuff muscles, it stabilizes the shoulder. Insertion areas are presented in Table 1 and visualized in Figure 2.There were two constant parts of the infraspinatus muscle. Origin: (proximal attachments) a. Supraspinous fossa of the scapula. Action: Laterally rotate arm; helps to hold humeral head in glenoid cavity of scapula. Origin of Infraspinatus muscle HONE FEATURES Latera Lateral view 4. Shoulder posterior internal impingement in the overhead athlete. Infraspinatus Muscle: The infraspinatus muscle is a thick triangular muscle, which occupies the most part of the infraspinatus fossa. The subacromial bursa lies between the remaining one third (bare area) of the scapula and the muscle and sometimes communicates with the shoulder joint. INSERTION: Medial of border of the scapula. Origin: Insertion: intertubercular groove Actions: adduction internal rotation . Origin, infraspinous fossa of scapula; insertion, middle facet of greater tubercle of humerus; action, extends arm and rotates it laterally; nerve supply, suprascapular (from fifth to sixth cervical spinal nerves). The Supraspinatus is a relatively small muscle of the upper back that make up the rotator cuff. The infraspinatus is composed of cross-striated muscles of mesodermal origin. Case Study: Structure Origin Insertion Action . The supraspinatus and infraspinatus muscles starts from 2 large fossae, 1 above and 1 below the spine, on the posterior surface of the scapula. Insertion . The insertion area of the infraspinatus at the greater tuberosity is clearly observed. Infraspinatus muscle: origin, functions, disorders The infrapinatu mucle, or muculu infrapinatu,together with the uprapinatu, the ubcapulari and the tere minor, it form the tructure known a the rotator cuff. The black line (asterisk) indicates the border between the insertion . Insertion: Distal to the greater tubercle of the humerus. Teres minor is a narrow and elongated muscle (cord-like muscle) that is completely hidden by the deltoid muscle and difficult to clearly delineate it from the infraspinatus muscle because teres minor muscle fibers may be fused with fibers of the infraspinatus muscle. The infraspinatus muscle, or musculus infraspinatus, forms together with the supraspinatus, the subscapularis and the teres minor the structure known as the rotator cuff. Part 1 (ISP1) was the largest part and had its origin at the infraspinous fossa. . Action: Flexes shoulder. Origin: Infraspinous fossa, scapular spine and the caudal border of the scapula. Nerve: Suprascapularis. Release and stretch the infraspinatus, teres minor and rear deltoid. Attachments of the infraspinatus Muscle Origin: Infraspinous fossa [] Purpose: To use moment arm values to indicate the efficacy of SCR and rTSA to . Levator scapulae. 1. nerve: spinal accessory (XI) and ventral. Insertion - Thoracolumbar fascia and the spinous processes of T7-L6. Answer. Superior aspect of the greater tubercle of the humerus. Rhomboid major. The infraspinatus muscle is supplied by the suprascapular nerve (C5 and C6), which arises from the superior trunk of the brachial plexus and passes laterally through the posterior triangle of the neck and through the scapular notch on the superior border of the scapula. The infraspinatus muscle is a thick triangular muscle, which occupies the chief part of the infraspinatous fossa. The infraspinatus muscle, or musculus infraspinatus, forms together with the supraspinatus, the subscapularis and the teres minor the structure known as the rotator cuff. Infraspinatus Infraspinatus fossa of scapula Greater tubercle of humerus Lateral rotation at shoulder Suprascapular Teres Minor Lateral border of scapula Greater tubercle of humerus Lateral rotation at shoulder Axillary . The upper limb bud lies in opposition to somites C4, C5, C6, C7, C8, T1, and T2. Muscle Function of Infraspinatus: Externally rotates the shoulder joint. It passes inferiorly surrounding the glenohumeral joint on all sides and inserts onto the humerus. ORIGIN: Transverse process of C1-C4. The Deltoid muscle is a thick, triangular shoulder muscle. Origin: Infraspinous fossa of thescapula Insertion: Middle facet of greater tubercle of the humerus Artery: Suprascapular and circumflex scapular arteries Nerve: Suprascapular nerve Action: Lateral rotation of arm and Adduction of arm and stabilizeshumerus Antagonist: Subscapularis, pectoralis major, and latissimus dorsi Description: The Infraspinatus is a thick triangular muscle . The shoulder is a ball and socket joint formed between the humerus and the scapula. Synonym (s): musculus infraspinatus [TA] . Nerve Supply: Suprascapular Nerve (C5 & C6) Blood . It is at this insertion that infraspinatus tendinitis most commonly occurs. The spine of the scapula separates the supraspinatus muscle from the infraspinatus muscle, which . Orbicularis Oculi. Teres Minor Muscle: Teres minor muscle is a narrow, elongated muscle of the rotator cuff. Medical Dictionary for the Health . Muscle Origin, Insertion, and Action List Charts 85 Muscles that act at Hip (to move leg) ACTION ORIGIN INSERTION Pectineus Flexes hip, adducts leg Pubis and pubic -- Select -- Supraspinatus Trapezius Triceps brachii Infraspinatus Deltoid Pectoralis major Subscapularis Biceps brachii Teres minor Latissimus dorsi. Insertion. Test yourself with our rotator. Insertion: The posterior aspect of greater tuberosity of the humerus, and the capsule of the shoulder joint. It helps in lateral rotation of the arm and stabilizes the humerus. The infraspinatus is the main external rotator of the shoulder. Testing the Infraspinatus While the patient stands with the elbow flexed to 90 degrees and pointing anteriorly. Infraspinatus muscle fibers originate most strongly from the deep aspect of the inferomedial band (Fig. When the arm is fixed, it adducts the inferior angle of the scapula. It may be associated with lack of prior athletic conditioning. When the muscle contracts, it'll pull the humeral head back and arm gets rotated laterally. Origin: Occipital bone and spinous processes of thoracic vertebrae. INSERTION: lateral third of clavIcle, acromion process, scapular spine. Circular muscle around the eyes. Background: Lines of action of the superior, middle, and inferior infraspinatus muscle fibers work together to produce moment arms that change throughout abduction in an intact shoulder, after a supraspinatus tear, and after superior capsular reconstruction (SCR) and reverse total shoulder arthroplasty (rTSA). It is at this insertion that infraspinatus tendinitis most commonly occurs. Action - Retraction of the scapula, flexion and internal rotation of the shoulder, lateral flexion and extension of the opposing LD muscle. 1. The shoulder muscles arise from a common early-muscle mass that is continuous with the pectoral mass and the common arm sheath known as the upper limb bud. The infraspinatus muscle is innervated by the suprascapular nerve. Origin: Infraspinous fossa of thescapula Insertion: Middle facet of greater tubercle of the humerus Artery: Suprascapular and circumflex scapular arteries Nerve: Suprascapular nerve Action: Lateral rotation of arm and Adduction of arm and stabilizeshumerus Antagonist: Subscapularis, pectoralis major, and latissimus dorsi Description: The Infraspinatus is a thick triangular muscle . Stabilizes shoulder. infraspinatus muscles. ORIGIN: occipital bone ,spinous processes of C1-T12. scaplular muscles include the supraspinatus, subscapularis, teres minor, infraspinatus, deltoid and teres major. Orbicularis Oris. In this video we will go through the anatomy of the infraspinatus muscle covering its; origin, insertion, action, nerve and blood supply. Closes and protrudes lips. origin: supraspinous fossa of the scapula; insertion: superior facet of the greater tubercle of the humerus; innervation: suprascapular nerve (C5,6); arterial supply: suprascapular and dorsal scapular arteries 2; action: abduction of the humerus; Gross anatomy Origin. Caused by exposure to cold & maladjustment of pillow during sleep. All originate from the scapula or shoulder blade and insert into the outermost portion of the humerus trochiter. The medical illustrations contained . Infraspinatus. Origin - Teres major tuberosity. In the horse, the aponeurosis of the deltoid is partially fused to the infraspinatus. 4 C). Introduction : The scapula provides attachment for several groups of muscles. Introduction. most upper body exercises; anything from DB internal rotations to bench to rows to pull ups). This article will primarily highlight the origin, insertion . Description. It is a member of the rotator cuff, commonly remembered by the mnemonic "SITS" (supraspinatus, infraspinatus, teres minor, subscapularis). Description. The Infraspinatus muscle is a thick, triangular shape of muscle; one of the 4 muscles which comprise the Rotator Cuff of the shoulder joints. Prevention is achieved by keeping dogs in good athletic condition and warming them up to full activity . Circular muscle around the mouth. Origin: Caudal border and spine of the scapula. The infraspinatus is a thick and triangular muscle. Characteristics of myofascial pain syndrome of the infraspinatus muscle. Insertions of Rhomboid Major, Rhomboid minor, Leyator Scapulae, and Serratus. 42-1). Anterior 5. The infraspinatus muscle has its origin in the infraspinous fossa of the scapula and inserts into the middle facet of the greater tuberosity of the humerus (see Fig. It's not the acceleration of throwing the ball as much as it is the eccentric control . Origin: Infraspinous fossa of scapula. dorsi List the exor muscles coracobrachialis pect major (upper bers) * from superior angle of root of spine. Infraspinatus muscle View Related Images. The infraspinatus muscle owes its name to the fact that it occupies a large part of the infraspinatus fossa of . is a small rotator cuff muscle, which is hidden from the surface of the physique. Palpation of Infraspinatus: The posterior surface inferior to the spine of the scapula. 42-1 ). Frontalis:Forehead to Galea Aponeurotica; Occipitalis:Galea Aponeurotica to Occipital Bone. Baseball pitchers classically tear the infraspinatus muscle. Background:Lines of action of the superior, middle, and inferior infraspinatus muscle fibers work together to produce moment arms that change throughout abduction in an intact shoulder, after a sup. cle (in'fr-sp'n-ts ms'l) Origin, infraspinous fossa of scapula; insertion, middle facet of greater tubercle of humerus; action, extends arm and rotates it laterally; nerve supply, suprascapular (from fifth to sixth cervical spinal nerves). Insertion :-It inserts into the middle impression on the greater tubercle of the humerus. The infraspinatus is the major muscle that facilitates external rotation of the shoulder joint. It originates with strong muscle fibers directly from the medial two-thirds of the infraspinous fossa, whereas its tendinous fibers arise from the ridges of the fossa. Epicranius: Frontalis & Occipitalis. cle. The teres minor (L. teres, round and long ; minor, smaller.) All originate from the scapula or shoulder blade and insert into the outermost portion of the humerus trochiter. These muscles allow the shoulder . Table 1. Like all rotator cuff muscles, it also helps stabilize the humeral head in the shoulder . 1. deltoid infraspinatus teres minor lat. Insertion of the Infraspinatus From the infraspinous fossa, the infraspinatus muscle travels upward. This will help improve internal rotator muscle activation and range of motion. These muscles attach to the scapular surface and assist with abduction and external and internal rotation of the glenohumeral joint. The infraspinous fossa contributes to both the shape and name of the infraspinatus muscle. It's one of the Rotator Cuff muscles providing the mechanical link between the posterosuperior and anterior parts of the rotator cuff. and fascia of supraspinatus and. Insertion: Deltoid tuberosity of humerus. It occurs due to a spasm of the trapezius muscle and sternocleidomastoid muscle in the neck. It is a large thin muscle that is triangular in shape. Origin: Infraspinous fossa of scapula. The infraspinatus muscle originates from the infraspinous fossa at the back side of the scapula. It is one of the four muscles of the rotator cuff, the main function of the infraspinatus is to externally rotate the humerus and stabilize the shoulder joint. These muscles contribute to help form the glenohumeral joint, which aids in shoulder joint motion and stability. Raises the eyebrows. Insertion The posterior aspect of greater tuberosity of humerus, and the capsule of shoulder joint. Nerve Supply Suprascapular Nerve (C5 & C6) Blood Supply Lesson Summary. The infraspinatus muscle and tendons are susceptible to trauma and to wear and tear from overuse . Description: Origin: Medial aspect of the infraspinous fossa of the scapula and the tendinous septa of the fossa Insertion: Middle aspect of the greater tubercle of the humerus Actions: Rotates the shoulder joint laterally Nerve supply: Suprascapular nerve Blood supply: Branches of the subclavian and . From this location, the infraspinatus muscle travels upward diagonally and inserts onto the greater tubercle of the humerus (long bone of the upper arm). It acts on the shoulder joint and is a prime mover (along with the infraspinatus) in shoulder external rotation. They create tendons that insert on the greater tubercle of the humerus. Insertion: Scapula and clavicle. Unformatted text preview: MUSCLE ORIGIN INSERTION Supraspinatus (13) Supraspinous fossa of scapula Greater tubercle of humerus Infraspinatus (14) infraspinous fossa of scapula Greater tubercle of humerus Teres minor (15) Inferior lateral border of scapula Greater tubercle of humerus Subscapularis (17) Subscapular fossa Lesser tubercle of humerus Biceps brachii (20) Radial tuberosity of radius . A tear of the infraspinatus could be the result of either an acute or chronic movement. Infraspinous fossa of scapula Middle part of greater tubercle of posterior humerus . Attachment of the Teres Minor Muscle Origin: The middle part of the lateral border of scapula Insertion: The inferior aspect of greater tubercle of the humerus Action of the Teres Minor Muscle Laterally rotates the arm at the shoulder joint. Origin The infraspinatus fossa of scapula, with some fibres arising from the infraspinatous fascia which covers the muscle and separates it from Teres Major and Teres Minor. Infraspinatus Laterally rotates humerus at shoulder. Origin: infraspinatus fossa of the scapula. We hope you enjoy i. A posterior view of the rotator cuff muscles. 4.2 Morphology of the infraspinatus muscle. It occurs due to irritation of the spinal accessory nerve caused by inflamed or suppurating lymph nodes. Infraspinatus Origin and Insertion The muscle arises from the infraspinous fossa (medial three fourth) and also from the deep surface of the infraspinous fascia that covers it. Shoulder posterior internal impingement in the overhead athlete. Summary. Stabilizes the head of humerus in the glenoid cavity during movements of the joint.