System: Musculoskeletal

Soleus Muscle

Soleus Muscle The structure indicated is the soleus muscle of the leg. The soleus is a muscle of the posterior compartment of the leg.The muscles in the posterior compartment of the leg are separated into a superficial group and a deep group. The superficial group consists of the following leg muscles: Gastrocnemius Plantaris Soleus The deep group consists of the following leg muscles: Popliteus Flexor hallucis longus Flexor digitorum longus Tibialis posterior The soleus muscle lies deep to the gastrocnemius and is large and flat in shape running the length of the leg from the knee to the heel, closely …

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Soleus Muscle

Inferior Extensor Retinaculum

Inferior Extensor Retinaculum The structure indicated is the inferior extensor retinaculum. Retinacula (retinaculum singular) are bands of connective tissue which surround tendons and hold them in place. They function to stabilise tendons as the muscles to which they attach contract to cause movement. There are retinacula in the wrist, ankle and knee. In the ankle, there is the flexor retinaculum, the peroneal retinacula and on the extensor surface, there is the superior and inferior extensor retinacula. The superior retinaculum is situated distally in the leg just above the ankle joint, attaching to the anterior aspects of the fibula and tibia. …

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Inferior extensor retinaculum

Deltoid Muscle

Deltoid Muscle The structure indicated is the deltoid muscle. There are several muscles which act on the glenohumeral joint to produce movement at the shoulder. The deltoid is a large, powerful superficial muscle which is responsible for giving the shoulder its characteristic contour. The deltoid muscle is comprised of three sets of muscle fibres: Anterior fibres Lateral fibres Posterior fibres The various groups of fibres of the deltoid muscle originate on the clavicle and scapula and converge to insert onto the deltoid tuberosity of the humerus. The anterior fibres originate from the anterior border of the lateral third of the …

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Deltoid muscle

Orbicularis Oculi

Orbicularis Oculi The structure indicated is the orbicularis oculi muscle of the face. The orbicularis oculi muscle is one of the muscles of facial expression belonging to the orbital group. The muscles of facial expression can be organised into functional groups to provide a more structured approach to understanding the muscles. The functional groups include the following: Orbital group Nasal group Oral group Other The orbicularis oculi muscle is the principle muscle of the orbital group of facial muscles and consists itself of two parts: Palpebral part Orbital part There is an additional muscle in the orbital group – the …

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Orbicularis Oculi

Styloid Process of Ulna

Styloid Process of Ulna The structure indicated is the styloid process of the ulna. The styloid process of the ulna is a bony process that extends from the distal end of the ulna bone. Attaching to the styloid process of the ulna is the ulnar collateral ligament of the wrist. Learn more about the anatomy of the radius and ulna in this tutorial
Styloid process of ulna

Intertubercular sulcus

Intertubercular Sulcus The structure indicated is the intertubercular sulcus of the humerus. The intertubercular sulcus, also known as the intertubercular groove, or bicipital groove, is a groove separating the greater and lesser tubercles of the humerus. The tendon of the long head of the biceps muscle runs in this groove and attaches on the supraglenoid tubercle of the scapula. The short head of the biceps muscle on the other hand has its origin on the coracoid process of the scapula. The intertubercular sulcus is the site of three important muscle attachments: Pectoralis major Latissmus dorsi Teres major The pectoralis major …

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intertubercular sulcus

Posterior Inferior Iliac Spine

Posterior Inferior Iliac Spine The structure indicated is the posterior inferior iliac spine of the pelvic bone. The pelvic bone consists of three parts: Ilium Ischium Pubis The posterior part of the ilium consists of two bony spines. Superiorly is the posterior superior iliac spine, and inferiorly is the posterior inferior iliac spine. Anteriorly is the anterior superior iliac spine and the anterior inferior iliac spine. Learn more about the anatomy of the pelvic bones in this tutorial.
Posterior inferior iliac spine

Anterior Inferior Iliac Spine

Anterior Inferior Iliac Spine The structure indicated is the anterior inferior iliac spine of the pelvic bone. The pelvic bones consist of three parts: Ilium Ischium Pubis The anterior part of the ilium consists of two bony spines. Superiorly is the anterior superior iliac spine (ASIS), and inferiorly is the anterior inferior iliac spine. Posteriorly is the posterior superior iliac spine and the posterior inferior iliac spine. The rectus femoris muscle of the quadriceps group of thigh muscles attaches to the anterior inferior iliac spine, as well as the iliofemoral ligament. Learn more about the anatomy of the pelvic bones …

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pelvis - anterior inferior iliac spine

Flexor Digiti Minimi Brevis

Flexor Digiti Minimi Brevis The structure indicated is the flexor digiti minimi brevis muscle of the foot. The intrinsic muscles on the plantar aspect of the foot are divided into four layers. The flexor digiti minimi brevis muscle is located in the third layer of intrinsic foot muscles. There are three muscles located in this layer: Flexor hallucis brevis Adductor hallucis Flexor digiti minimi brevis Origin: Base of 5th metatarsal Insertion: lateral base of proximal phalanx of little toe Action: flexes little toe at metatarsophalangeal joint Innervation: lateral plantar nerve   Learn more about the anatomy of the foot muscles in …

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flexor digiti minimi brevis

Extensor Carpi Ulnaris

Extensor Carpi Ulnaris The structure indicated is the extensor carpi ulnaris muscle of the forearm. The extensor carpi ulnaris 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 …

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extensor carpi ulnaris