Muscles

Vastus Lateralis

Vastus Lateralis The structure indicated is the vastus lateralis The vastus lateralis is one of the muscles that makes up the quadriceps femoris, and is contained in the anterior compartment of the thigh. The muscles of the anterior compartment are all innervated by the femoral nerve and serve generally to extend the leg at the knee joint. The four muscles that make up the quadriceps femoris are the: Rectus femoris Vastus lateralis Vastus medialis Vastus intermedius In addition to the quadriceps muscles, the Sartorius muscle is also located in the anterior compartment together with the distal ends of the iliopsoas …

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Vastus Lateralis

Pectineus

Pectineus The structure indicated is the pectineus muscle. The pectineus muscle is one of six muscles in the medial compartment of the thigh. The thigh consists of three muscular compartments: Anterior Medial Posterior The medial compartments consists of the following muscles: Gracilis Pectineus Adductor longus Adductor brevis Adductor magnus Obturator externus All the muscles of the medial compartment are innervated by the obturator nerve except for the pectineus (femoral nerve) and the hamstring part of the adductor magnus (tibial division of sciatic). The muscles of the medial compartment generally serve to adduct the thigh at the hip joint. Due to …

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Pectineus

Infraspinatus

Infraspinatus The structure indicated is the infraspinatus muscle of the rotator cuff. The infraspinatus muscle is one of the four muscles of the rotator cuff. The rotator cuff muscles are located in the posterior scapula region and serve to stabilise the glenohumeral joint. There are 4 rotator cuff muscles which can be remembered using the mnemonic SITS: Supraspinatus Infraspinatus Teres minor Subscapularis The supraspinatus and infraspinatus, as their names suggest originate in the fossae above and below the spine of the scapula respectively (supraspinatous and infraspinatous fossae). The supraspinatus, infraspinatus and teres minor muscles insert on to the greater tubercle …

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Infraspinatus

Extensor Digitorum Longus

Extensor Digitorum Longus The structure indicated is the extensor digitorum longus muscle. The extensor digitorum longus is one of the four muscles of the anterior compartment of the leg. The muscles of the leg consist of three compartments: Anterior Posterior Lateral In the anterior compartment are the four following muscles: Tibialis anterior Extensor hallucis longus Extensor digitorum longus Fibularis tertius The muscles of the anterior compartment of the leg serve to dorsiflex the ankle joint, extend the toes and invert the foot, and they are supplied by the deep fibular (peroneal) nerve. Origin: Proximal ½ of medial surface of fibula. …

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extensor digitorum longus

Extensor Digiti Minimi

Extensor Digiti Minimi The structure indicated is the extensor digiti minimi muscle. The extensor digiti minimi muscle is one of 7 muscles located in the superficial compartment of the posterior forearm. The posterior forearm consists of a superficial and a deep compartment. The superficial compartment contains 7 muscles, whereas the deep compartment contains 5 muscles. The superficial compartment of the posterior forearm includes the following 7 muscles: Brachioradialis Extensor carpi radialis longus Extensor carpi radialis brevis Extensor digitorum Extensor digiti minimi Extensor carpi ulnaris Anconeus The muscles of the posterior compartment of the forearm originate from the lateral epicondyle of the humerus and the supraepicondylar ridge and they are all innervated by …

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extensor digiti minimi

Brachialis

Brachialis The structure indicated is the brachialis muscle. The brachialis muscle is one of three muscles in the anterior compartment of the arm: Biceps brachii Brachialis Coracobrachialis The muscles of the anterior compartment are innervated by the musculocutaneous nerve and generally serve to flex the forearm at the elbow joint. The brachialis muscle lies deep to the biceps brachii muscle and is synergistic in its action, assisting with flexion of the forearm at the elbow joint. Origin: Distal half of anterior humerus Insertion: Ulna tuberosity Action: Flexion of elbow Innervation: Musculocutaneous nerve Learn more about the anatomy of the arm …

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Brachialis

Biceps Brachii – Long Head

Biceps Brachii – Long Head The structure indicated is the long head of the biceps brachii muscle. The biceps muscle is one of three muscles in the anterior compartment of the arm: Biceps brachii Brachialis Coracobrachialis The muscles of the anterior compartment are innervated by the musculocutaneous nerve and generally serve to flex the forearm at the elbow joint. The biceps brachii muscle is comprised of two muscular heads: Short head Long head The long head of the biceps brachii originates on the supraglenoid tubercle of the scapula, and traverses the superior aspect of the glenohumeral joint to descend in …

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biceps brachii long head

Semimembranosus

Semimembranosus The structure indicated is the semimembranosus muscle. The semimembranosus muscle is one of three muscles in the posterior compartment of the thigh. The other muscles are the semitendinosus, and the biceps femoris. The muscles in the posterior compartment are often referred to as the “hamstrings” muscles. Collectively, these muscles are responsible for extending the hip joint, and flexing the knee joint. The biceps femoris lies laterally, and the semitendinosus and semimembranosus lie medially. The semitendinosus gets its name from its structure which is comprised of a muscle belly which tapers into a long tendon that extends to insert onto …

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semimembranosus

Gluteus Medius

Gluteus Medius The structure indicated is the gluteus medius muscle. The gluteus medius muscle is one of the muscles of the gluteal region. The muscles in the gluteal region are divided into a superficial and deep group. There are four muscles of the superficial group: Gluteus maximus Gluteus medius Gluteus minimus Tensor fasciae latae There are 5 muscles in the deep group: Gemellus superior Gemellus inferior Quadratus femoris Piriformis Obturator internus Origin: Dorsal ilium inferior to iliac crest Insertion: Lateral and superior surfaces of greater trochanter Action: Hip abduction. Hip medial rotation (medial fibres). Hip lateral rotation (posterior fibres) Innervation: …

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gluteus medius

Teres Minor

Teres Minor The structure indicated is the teres minor muscle. The teres minor muscle is one of the four muscles of the rotator cuff. The rotator cuff muscles are located in the posterior scapula region and serve to stabilise the glenohumeral joint. There are 4 rotator cuff muscles which can be remembered using the mnemonic SITS: Supraspinatus Infraspinatus Teres minor Subscapularis The supraspinatus and infraspinatus, as their names suggest originate in the fossae above and below the spine of the scapula respectively (supraspinatous and infraspinatous fossae). The supraspinatus, infraspinatus and teres minor muscles insert on to the greater tubercle of …

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Teres minor