Body Viz

Anterior neck muscles. Love anatomy The anterior neck muscles are a group of muscles covering the anterior aspect of the neck. They are further divided into 3 subgroups: The superficial muscles are the most superficial in the anterior neck, and include the platysma and sternocleidomastoid. The suprahyoid muscles, as the name suggests, are found superior to the hyoid bone, and include the digastric, mylohyoid, geniohyoid and stylohyoid. The infrahyoid muscles are found inferior to the hyoid bone and consist of the sternohyoid, omohyoid, sternothyroid and thyrohyoid.

The natural history of lumbar disc herniation indicates that they may decrease in size or even disappear within a few weeks or months of onset. In migrated or extruded herniations, phagocytosis of the herniated disc by the macrophages occurs, while, in contained herniations, dehydration of the herniated nucleus pulposus plays a major role in the reduction of the herniated disc size.

Lumbar discectomy is the most common operation performed in the United States for lumbar-related symptoms. Lumbar disc herniation accounts for only 5% of all low back pain problems but is the most common cause of radiating nerve root pain (sciatica). The natural history of lumbar disc herniation indicates that they may decrease in size or even disappear within a few weeks or months of onset. In migrated or extruded herniations, phagocytosis of the herniated disc by the macrophages occurs, while, in contained herniations, dehydration of the herniated nucleus pulposus plays a major role in the reduction of the herniated disc size. Approximately 90% of acute sciatica attacks improve with conservative management; thus, the mainstay of treatment for a patient with symptomatic lumbar disc herniation continues to be nonoperative methods, such as treatment with anti-inflammatory medications, physical therapy, and lumbar injection, unless the patient has an acute or progressive neurological deficit. Indications for lumbar discectomy include altered bladder and bowel function and progressive neurological deficits such as motor weakness or sensory deficit in the lower extremities. Surgery should also be considered in patients with radicular pain that persists after an adequate course of conservative management.

Mylohyoid muscle is one of the suprahyoid muscles that, together with geniohyoid muscle forms the floor of the oral cavity. Along with the other suprahyoid muscles (digastric, geniohyoid and stylohyoid), it connects the hyoid bone to the skull. The functions of this muscle are to facilitate speech and deglutition by elevating the floor of the mouth and hyoid bone and depressing the mandible. Attaching between the mandible and hyoid bone, the mylohyoid muscle has the following actions; Like all the other suprahyoid muscles, it elevates both the hyoid bone and floor of mouth, when the mandibular attachment is fixed. It depresses mandible with the hyoid attachment fixed. With its elevating actions on hyoid and floor of the mouth, the mylohyoid muscle aids deglutition by pressing the tongue against the hard palate, thus pushing the bolus towards the pharynx. Along with digastric and geniohyoid muscles, the mylohyoid can depress the mandible against resistance, separating teeth that may be held together by food and facilitating chewing.

The longissimus muscle forms the central column of the erector spinae muscle group and is the longest and thickest of this group. It is divided into three regions based on their attachments: Longissimus capitis Longissimus cervicis Longissimus thoracis, which is further subdivided into thoracic and lumbar parts. Generally speaking, longissimus muscle is a powerful extensor of the vertebral column. However, its exact function depends on the degree of engagement of the different muscle parts. Bilateral contraction of the entire muscle results in extension of the lumbar, thoracic and cervical spine, along with extension of the head and neck. Unilateral contraction of the longissimus muscle results in lateral flexion of the spine on the same side (ipsilaterally). An alternated unilateral contraction of the left and right longissimus aids the walking process by leveling the pelvis and steadying the vertebral column.

Longissimus thoracis active stretching Sit on the floor, straighten your legs and slowly reach forward until you feel a stretch in your lower back. Pain is complex, and although this exercise may help a lot of people, it may not be appropriate for everyone. This is just 1 option. There are a lot of other exercises that work with the same intent that you can add to this or might even work better for you. It’s also important to address things like sleep, stress, mood, hydration, prolonged postures or repetitive movements as well.

Iliacus is a triangular muscle of the iliac region which together with the psoas major, comprises the iliopsoas muscle. The iliacus muscle has a vast origin, the majority of it arising from the superior two-thirds of the iliac fossa. The rest arises from several other origin points, which are the inner lip of the iliac crest, the lateral aspect of the sacrum and anterior sacroiliac and iliolumbar ligaments. The muscle fibers converge distally towards the hip, thus contributing to the triangular shape of this muscle. At the level of the capsule of the hip joint, the iliacus muscle fibers blend with those of the psoas major muscle, forming a common tendon for the iliopsoas. The tendon of iliopsoas crosses the anterior surface of the hip joint to finally insert to the lesser trochanter of femur. Before insertion, the tendon of iliopsoas receives a small slip called the iliocapsularis muscle, which is a small muscle lying just superficial to the hip joint capsule. The iliacus muscle is innervated by the femoral nerve (L2-L4). The iliacus muscle works in synergy with the psoas major muscle to produce movements in the hip joint. When its proximal attachment is fixed, the muscle contributes to the flexion of the thigh. On the other hand, with its distal attachment fixed, the muscle helps to bring the trunk forwards against resistance. These actions are essential for lower limb functions such as walking, running and jumping.

The shoulder girdle, also called the pectoral girdle, is an incomplete bony ring formed by the clavicle and scapula on each side of the body, joined anteriorly by the manubrium of the sternum. The bones of the shoulder girdle articulate with each other and partake in the formation of 4 joints that include: The sternoclavicular joint - formed between the sternum and clavicle. The acromioclavicular (AC) joint - formed between the scapula and the clavicle. The glenohumeral (shoulder) joint - formed between the scapula and humerus. The scapulothoracic joint - formed between the scapula and the posterior thoracic cage. The shoulder girdle functions as the anchor that attaches the upper limbs to the axial skeleton. Additionally, the shoulder girdle allows for a large range of motion, mainly in the highly mobile scapulothoracic joint. The muscles of the shoulder support and produce the movements of the shoulder girdle. They attach the appendicular skeleton of the upper limb to the axial skeleton of the trunk. Four of them are found on the anterior aspect of the shoulder, whereas the rest are located on the shoulder’s posterior aspect and in the back. Anterior axio-appendicular muscles: Pectoralis major, pectoralis minor, subclavius and serratus anterior.

The sphenoid is an unpaired butterfly-shaped bone of the neurocranium. It forms the middle aspect of the skull base and connects with the frontal, parietal, temporal and occipital bones. Also, it participates in the formation of the middle cranial fossa. I sincerely hope you enjoy it please follow my channel if you want to learn new scientific material every day.

Piriformis is a muscle of the gluteal region which lies deep to the gluteus maximus. Piriformis belongs to a group of six short external rotators of the hip , i.e. gemellus superior, obturator internus, gemellus inferior, quadratus femoris, obturator externus. Attaching to the sacrum on one end and the greater trochanter on the other one, this muscle is reponsible for stabilising the hip joint and moving the thigh in various directions. This is a flat pyramid-shaped muscle that arises from the anterior surface of the sacrum, between the sacral foramina. It passes laterally to exit the bony pelvis through the greater sciatic foramen, often attaching to the gluteal surface of the ilium, close to the posterior inferior iliac spine. It inserts onto the apex of the greater trochanter, posterosuperior to the insertion site of the conjoined tendon of gemellus superior, obturator internus and gemellus inferior. The muscle divides the greater sciatic foramen into two foramina (suprapiriform and infrapiriform). The superior gluteal artery and nerve (L4-S1) leave the pelvis through the suprapiriform foramen. The sciatic nerve, inferior gluteal nerve (L5-S2) and artery, posterior femoral cutaneous nerve (S1-S3) and the nerve to quadratus femoris (L4-S1) leave the pelvis through the infrapiriform foramen. The pudendal nerve (S2-4) also leaves the pelvis through the infrapiriform foramen, wraps around the sacrospinous ligament, and re-enters the pelvis by passing back into the lesser sciatic foramen. After re-entering the pelvis, it is joined by the internal pudendal artery and vein. The gluteus medius and minimus are medial rotators, and hence oppose the action of the lateral rotators.

Force couple relationship refers to a biomechanical concept in which two or more muscles act together to produce a coordinated movement around a joint. In a force couple, each muscle produces a force at a different angle than the other muscles, but the combined effect of all the forces is a rotational movement around the joint. The muscular forces are often synergistic, meaning the main muscle performs a specific action while the other muscles stabilise the joint to prevent injury or displacement of the bones. An example of a synergistic force couple relationship is that of the trapezius and serratus anterior muscles acting around the scapula (shoulder blade) to stabilise it during movements of the arm. The upper fibers of the trapezius elevate the scapula, while its lower fibers protract and rotate it medially. The upper fibers of the serratus anterior protract and suspend the scapula, while its lower fibers pull the lower angle of the shoulder blade forward. Together, these muscles perform scapular rotation to allow the arm to be raised above the head.

The popliteus muscle is a small muscle that forms the floor of the popliteal fossa. It belongs to the deep posterior leg muscles, along with tibialis posterior, flexor digitorum longus and flexor hallucis longus. The popliteus muscle extends over the posterior aspect of the knee joint. It originates from the femur and the posterior horn of the lateral meniscus, and inserts on the proximal tibia. The popliteus muscle plays an important role in the gait cycle by initiating the flexion of the fully extended (“locked”) knee. Thus, the popliteus is referred to as the “key to unlock the knee”. In addition, the popliteus muscle is the main stabiliser of the posterior knee region.

Every adolescent has heard at least once “don’t forget your head somewhere!” from their parents. Well, luckily, we have necks that attach our heads to our trunks, so joke’s on them for saying that. For instance, it supports the position of the head and enables us to turn our head towards stimuli. The content of the neck is grouped into 4 neck spaces, called the compartments. Vertebral compartment: contains cervical vertebrae and postural muscles. Visceral compartment: contains glands (thyroid, parathyroid, and thymus), the larynx, pharynx and trachea. Two vascular compartments: contain the common carotid artery, internal jugular vein and the vagus nerve, on each side of the neck. Protection of the parts of the neck and its mobility are ensured by the vertebrae and muscles of the neck.

he heart is a muscular organ that pumps blood around the body by circulating it through the circulatory/vascular system. It is found in the middle mediastinum, wrapped in a two-layered serous sac called the pericardium. The heart is shaped as a quadrangular pyramid, and orientated as if the pyramid has fallen onto one of its sides so that its base faces the posterior thoracic wall, and its apex is pointed toward the anterior thoracic wall. The great vessels that originate from the heart, radiate their branches to the head and neck, the thorax and abdomen and the upper and lower limbs. Borders Superior (atria, auricles), inferior (right and left ventricles), left (left auricle, left ventricle), right (right atrium) borders Surfaces: Sternocostal (right ventricle), diaphragmatic (mostly right ventricle, portion of left ventricle), pulmonary (cardiac impression) surfaces Chambers: Atria (left and right), ventricles (left and right) Emerging/entering vessels Pulmonary veins (-> left atrium), superior and inferior vena cavae (-> right atrium), aorta (left ventricle ->), pulmonary artery (right ventricle ->) Valves: Tricuspid, pulmonary, mitral, aortic valves Mnemonic: Try Pulling My Aorta

Extending from the mouth to the anus, the digestive tract is one of the largest systems in the human body. It contains organs that regulate food intake, its digestion and absorbtion of the useful materia that it contains. In addition to this, the digestive system also eliminates the waste products from food and products from various endogenous metabolic processes. In a nutshell, the digestive tract has the tumultuous responsibility of converting large chunks of food into their constituent micro-molecules that will subsequently be used to build and repair the body.

In the human body, the rotator cuff is a functional anatomical unit located in the upper extremity. Its function is related to the glenohumeral joint, where the muscles of the cuff function both as the executors of the movements of the joint and the stabilisation of the joint as well. Injuries of the rotator cuff interfere with the function of the glenohumeral joint and correspond with inability to perform the movements associated with this joint. Supraspinatus muscle Origin: supraspinatous fossa of scapula Insertion: greater tubercle of humerus Innervation: suprascapular nerve (C4, C6) Function: initiation of abduction of arm to 15° at glenohumeral joint; stabilisation of humeral head in glenoid cavity.

This video reviews such a complex movement as arm abduction. Abduction of the arm happens in the frontal plane and can be described as the arm’s movement away from the body’s midline. So, abduction at the shoulder joint causes the free upper limb to move away from the body. It begins with the upper limb positioned parallel to the body and the hand being in an inferior position, continues with the movement of the upper limb to a position perpendicular to the body and ends with the upper limb raised above the shoulder and pointing upward. This movement involves multiple joints and is closely related to the scapulohumeral rhythm, which can be described as a coordinated interaction between the scapula, clavicle, and humerus to achieve full abduction. It’s important to understand that the first 30 degrees of arm abduction constitute the setting phase, meaning that the movement is mainly glenohumeral, and the scapula remains stationary. Also, the clavicle demonstrates minimal or no movement. Only after the initial 30 degrees the scapula starts to move, and the glenohumeral and scapulothoracic joints begin to move simultaneously.

The pelvis is inferior most part of the trunk. Consisting of the pelvic girdle and perineum, it supports the urinary and reproductive organs. The pelvic floor is formed by the funnel-shaped pelvic diaphragm. The pelvic diaphragm comprises of the two paired muscles and their fasciae; levator ani muscle and the coccygeus muscle. The function of the pelvic diaphragm is to support the pelvic organs and prevent them from prolapse.

The human hand, the most distal part of the upper limb, is a remarkable feat of engineering and evolution. It is strong enough to allow climbers to tackle any mountain, but also sufficiently precise for the manipulation of some of the world’s smallest objects and the performance of complex actions. The hand itself consists of specific bones onto which various muscles are attached, and a collection of neurovascular structures responsible for drainage and innervation. However, the intrinsic muscles of the hand are only partially responsible for all its range of motion. The other major contributors are actually the forearm muscles, which project tendons towards the hand via an equally complex and flexible anatomical structure, called the wrist. The muscles of the hand consist of five groups: Thenar muscles Hypothenar muscles Lumbricals Palmar interossei Dorsal interossei

Rotator cuff surgery for the supraspinatus muscle. Arthroscopic treatment of rotator cuff disease initially consisted of rotator cuff inspection and debridement and arthroscopic acromioplasty. If a repairable rotator cuff tear was discovered, an open or miniopen repair of the tendon was then performed. As surgeons’ skills improved and more specialised instrumentation was developed, it became possible to fix relatively small tears by using arthroscopic techniques to insert anchors, pass sutures, and tie knots. In current practice, surgeons can use these arthroscopic techniques in the shoulder to repair even large rotator cuff tears. An overly aggressive acromioplasty must be avoided because excessive removal of the anterior acromion can result in the humeral head sliding forward, up, and out of the socket (anterosuperior subluxation). The rotator cuff tear is then visualized through the lateral (side) portal from the “50-yard-line view.” The size and pattern of the tear are assessed. Any thin or fragmented portions are removed, and the area where the tendon will be reattached to the bone is lightly debrided to encourage new blood vessel ingrowth for healing. The sutures are once again passed through the tendon and systematically tied. The sutures pull the tendon down to the prepared bone surface, closing the defect. This completes the repair.

Please note this is just an animation. Some people can have tears and have no pain and not all tears require surgery. Rotator cuff injuries are a common cause of shoulder pain in people of all age groups. They represent a spectrum of disease, ranging from acute reversible tendinitis to massive tears involving the supraspinatus, infraspinatus, and subscapularis. Diagnosis is usually made through detailed history, physical examination, and often, imaging studies. Several primary causes of rotator cuff pathology have been described, including age-related degeneration, compromised microvascular supply, and primary outlet impingement. Secondary factors (eg, GH instability) also appear to be related to rotator cuff injuries. Pain control and inflammation reduction are initially required to allow progression of healing and initiation of an active rehabilitation program in patients with a rotator cuff injury.

The rhomboids are two bilateral, superficial muscles located in the upper back. They consist of two functionally similar muscles called rhomboid minor and rhomboid major. Together with trapezius, levator scapulae and latissimus dorsi, they comprise the superficial layer of the extrinsic back muscles. The rhomboid muscles extend between the nuchal ligament, spinous processes of thoracic vertebrae and scapula. Under innervation from the dorsal scapular nerve, the rhomboids primarily retract the scapula superomedially and rotate the glenoid cavity. Therefore, the rhomboids are important to stabilise the scapula into position and reinforce the shoulder. Rhomboid major is a broad quadrilateral muscle that originates from the spinous processes of the second to second to fifth thoracic vertebrae (T2-T5). The muscle extends obliquely in an inferolateral direction to insert into the medial border of scapula, between the inferior angle and root of the spine of scapula. The attachment takes place both on the dorsal and costal aspects of the medial border of scapula. The main action of the rhomboid muscles is scapular retraction around the scapulothoracic joint. Scapular retraction is a simultaneous sliding of the scapula superiorly and medially along the trunk. This superomedial movement of the scapula rotates the glenoid cavity inferiorly, dropping the shoulder girdle. By opposing excessive scapular protraction, the rhomboids help to maintain a correct posture when sitting, standing and walking.

Surgical intervention is required when neurologic dysfunction and/or instability occurs as a result of the lumbar fracture. Neurologic problems may manifest in many ways. Reduced leg strength (paresis) or complete weakness (paralysis) is an obvious problem. Loss of sensation in the lower extremities and in the perianal area (saddle anesthesia) can be just as important. Urinary retention and urinary and fecal incontinence are very important signs that indicate the need for emergency surgery. Vertebroplasty has been available for many years. This procedure involves injecting a form of cement polymer into the fractured vertebral body. The vertebral body then has better resistance to physiologic loads when the patient is upright, thus decreasing the amount of pain associated with the fracture. The procedure may be performed with the patient under local or general anesthesia. A percutaneous trocar or large needle is introduced into the fractured body through the pedicle, and the cement is injected. Fluoroscopy is used to guide the surgeon for correct localization.

The lateral flexion of head and cervical spine is a movement in which your head and neck bend to one side of the body. This motion includes: Anterior intertransversarii muscles Posterior intertransversarii muscles Trapezius muscle Sternocleidomastoid muscle Iliocostalis colli muscle Levator scapulae muscle Longissimus capitis muscle Longissimus colli muscle Scalene anterior muscle Scalene posterior muscle Scalene medius muscle Semispinalis capitis muscle Splenius capitis muscle Splenius colli muscle

The pectoralis major is a paired, superficial muscle located on the anterior surface of the thoracic cage. If you’re a gym lover, you’ll hear these muscles also being referred to as the pecs muscles. The pectoralis major has a broad origin, based on which it is divided into three parts: clavicular part, sternocostal part and abdominal part. All three parts converge laterally and insert onto the greater tubercle of humerus. The pectoralis major muscle is a fan-shaped muscle that consists of three parts that originate from three different sites: The clavicular part originates from the anterior surface of the medial half of the clavicle. The sternocostal part originates from the anterior surface of sternum and the anterior aspects of the costal cartilages of ribs 1-6. The smallest, abdominal part originates from the anterior layer of the rectus sheath. The muscle fibers from all three parts run laterally, converging towards the proximal humerus. They give off a broad tendon that inserts along the crest of the greater tubercle of the humerus. The pectoralis major muscle is innervated by the lateral and medial pectoral nerves (root value C5-T1), which stem from the brachial plexus.