Monday, 17 November 2014

Subclavius muscle Detail :

Subclavius muscle:-

The subclavius is a small triangular muscle, placed between the clavicle and the first rib. Along with the pectoralis major and pectoralis minor muscles, the subclavius muscle makes up the anterior wall of the axilla.
 

Structure:-

It arises by a short, thick tendon from the first rib and its cartilage at their junction, in front of the costoclavicular ligament.

The fleshy fibers proceed obliquely superolaterally, to be inserted into the groove on the under surface of the clavicle between the trapezoid ligament and conoid ligaments, which collectively form the coracoclavicular ligament.
 

Innervation:-

The nerve to subclavius (or subclavian nerve), which arises from the point of junction of the fifth and sixth cervical nerves, where is called the upper trunk of brachial plexus, innervates the muscle .
Variation:-


Insertion into coracoid process instead of clavicle or into both clavicle and coracoid process. Sternoscapular fasciculus to the upper border of scapula. Sternoclavicularis from manubrium to clavicle between pectoralis major and coracoclavicular fascia.
 

Function:-


The subclavius depresses the shoulder, carrying it downward and forward. It draws the clavicle inferiorly as well as anteriorly.

The subclavius protects the underlying brachial plexus and subclavian vessels from a broken clavicle - the most frequently broken long bone.


Origin:-
    first rib and cartilage
 

Insertion:-
    subclavian groove of clavicle (inferior surface of middle third of clavicle)
 

Artery:-
    thoracoacromial trunk, clavicular branch
 

Nerve:-
    nerve to subclavius
 

Actions:-     depression of clavicle.

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Saturday, 15 November 2014

The Sternocleido-Mastoid Muscle Detail

The sternocleidomastoid  muscle:-

   In human anatomy, the sternocleidomastoid muscle also known as sternomastoid and commonly abbreviated as SCM, is a paired muscle in the superficial layers of the anterior portion of the neck; it is one of the largest and most superficial cervical muscles.


Structure:-The sternocleidomastoid passes obliquely across the side of the neck.

It is thick and narrow at its central part, but broader and thinner at either end.

    The medial or sternal head is a rounded fasciculus, tendinous in front, fleshy behind, which arises from the upper part of the anterior surface of the manubrium sterni, and is directed superiorly, laterally, and posteriorly.

    The lateral or clavicular head, composed of fleshy and aponeurotic fibers, arises from the superior border and anterior surface of the medial third of the clavicle; it is directed almost vertically upward.

The two heads are separated from one another at their origins by a triangular interval (supraclavicular fossa) but gradually blend, below the middle of the neck, into a thick, rounded muscle which is inserted, by a strong tendon, into the lateral surface of the mastoid process, from its apex to its superior border, and by a thin aponeurosis into the lateral half of the superior nuchal line of the occipital bone.usculus sternocleidomastoideus

Origin:-
    Manubrium sterni and medial portion of the clavicle
 

                                              Insertion:-

Mastoid process of the temporal bone, superior nuchal line

Artery:-

Occipital artery and the superior thyroid artery
 

Nerve:-    Motor: accessory nerve
                       sensory: cervical plexus

Actions:-     Unilaterally; cervical rotation to opposite side, 
                            cervical lateral flexion to same side
                         Bilaterally; cervical flexion, raises the sternum and assists in forced inspiration.


Stretching and strengthening Exercises SCM Muscle :

Stretching and strengthening Exercises for the Sternocleidomastoid(SCM) Muscle :

The sternocleidomastoid is an important neck muscle that performs several functions requiring two different stretches and two different exercises for strengthening. 
The SCM muscle has two parts, the front and the back portion; also this muscle rotates, extends and flexes the neck to the side. More than one stretch and strengthening exercise are necessary to make this muscle flexible and strong.

Neck Retraction :

             
Neck Retraction Exercise


The neck retraction exercise is a stretch that targets the SCM. To perform this exercise, pull your chin back so the neck aligns neutrally with the spine. The neck retraction is also a posture exercise, because you should always center your neck over your shoulders. This exercise combats the postural deficiency known as forward head posture, a common problem whereby people extend their neck forward by jutting the chin. This tightens the SCM. To do this stretch, align your chin parallel to the floor and pull your head back. Hold the chin retracted for 20 to 30 seconds.

Side Neck and Rotation Stretch :

                  
Neck Exercise

         The side neck and rotation stretch lengthens the SCM muscle in a different manner than the neck retraction. This stretching exercise lengthens the SCM through bending the neck sideways and rotating it away from the side you are stretching. To begin, stand up tall and retract your neck. Then, tilt your head to the left and rotate your chin to point upward to the right until you feel a stretch on the right side of your neck. Hold for 20 to 30 seconds and repeat on the other side.

Wall Side Neck Bridge :

The wall side neck bridge strengthens the SCM through lateral flexion, or sideways bending. This exercise uses your body weight as resistance and a wall as an object for the SCM to push against. To begin, stand with your left side against a post or wall. Place the left side of your head against the wall. Hold hands behind your back. Then, step your feet to the right slightly so that you can lean diagonally left against the wall with your feet touching and legs straight. This is the starting position. Next, push against the wall to tilt your neck to the left and move your body to the right. Repeat on the other side.

Wall Front Neck Bridge :


The wall front neck bridge uses a wall and your body weight to strengthen the SCM through a forward flexion instead of a sideways bending of the neck. To perform this exercise, place a small cushioned mat against a wall at chest height. Do not use a pillow or something that your skin will slip on. Step your feet back with your legs straight and lean forward to place the top of your forehead against the cushion. Hold hands behind your back and straighten your back in line with your legs. Then, extend your chin toward the cushion, which causes your back and hips to move backward. Your forehead rolls downward and your nose touches the mat.

Related Other Muscle Post :
 Deltoid Muscle Detail
Deltoid- Shoulder Muscle Details




TRAPEZIUS MUSCLE

TRAPEZIUS MUSCLE
Trapezius Muscle Area

In human anatomy, the trapezius is a large superficial muscle that extends longitudinally from the occipital bone to the lower thoracic vertebrae and laterally to the spine of the scapula (shoulder blade). Its functions are to move the scapulae and support the arm.

The trapezius has three functional regions: the superior region (descending part), which supports the weight of the arm; the intermediate region (transverse part), which retracts the scapulae; and the inferior region (ascending part), which medially rotates and depresses the scapulae.


STRUCTURE

The trapezius muscle resembles a trapezium (trapezoid in American English), or diamond-shaped quadrilateral. The word "spinotrapezius" refers to the human trapezius, although it is not commonly used in modern texts. In other mammals, it refers to a portion of the analogous muscle.
Position of trapezius and its parts.

  • Superior fibers of the trapezius
  • Middle fibers of the trapezius
  • Inferior fibers of the trapezius
The superior or upper (or descending) fibers of the trapezius are formed from the external occipital protuberance, the medial third of the superior nuchal line of the occipital bone (both in the back of the head), the ligamentum nuchae, and the spinous processes of C1-C7. From this origin they proceed downward and laterally to be inserted into the posterior border of the lateral third of the clavicle.

The middle fibers, or transverse of the trapezius arise from the spinous process of the seventh cervical (both in the back of the neck), and the spinous processes of the first, second, and third thoracic vertebrae. They are inserted into the medial margin of the acromion, and into the superior lip of the posterior border of the spine of the scapula.

The inferior or lower (or ascending) fibers of the trapezius arise from the spinous processes of the remaining thoracic vertebrae (T4-T12). From this origin they proceed upward and laterally to converge near the scapula and end in an aponeurosis, which glides over the smooth triangular surface on the medial end of the spine, to be inserted into a tubercle at the apex of this smooth triangular surface.

At its occipital origin, the trapezius is connected to the bone by a thin fibrous lamina, firmly adherent to the skin. The superficial and deep epimysia are continuous with an investing deep fascia that encircles the neck and also contains both sternocleidomastoid muscles.

At the middle, the muscle is connected to the spinous processes by a broad semi-elliptical aponeurosis, which reaches from the sixth cervical to the third thoracic vertebræ and forms, with that of the opposite muscle, a tendinous ellipse. The rest of the muscle arises by numerous short tendinous fibers.


Origin: external occipital protuberance, nuchal ligament, medial superior nuchal line, spinous processes of vertebrae C7-T12
Insertionposterior border of the lateral third of the clavicle, acromion process, and spine of scapula
Artery:
Superficial branch of transverse cervical artery or superficial cervical artery
Nerve:
Accessory nerve (motor)
cervical spinal nerves C3 and C4 (motor and sensation)
Actions:  rotation, retraction, elevation, and depression of scapula


Friday, 14 November 2014

Deltoid Muscle Anatomy

Deltoid Muscle: Base Of Upper Limb

In human anatomy, the deltoid muscle is the muscle forming the rounded contour of the shoulder.
Deltoid Muscle
Anatomically, it appears to be made up of three distinct sets of fibers though electromyography suggests that it consists of at least seven groups that can be independently coordinated by the central nervous system.

It was previously called the deltoideus (plural deltoidei) and the name is still used by some anatomists. It is called so because it is in the shape of the Greek letter Delta (triangle). It is also known as the common shoulder muscle, particularly in lower animals (e.g., in domestic cats). Deltoid is also further shortened in slang as "delt".

A study of 30 shoulders revealed an average mass of 191.9 grams (6.77 oz) (range 84 grams (3.0 oz)–366 grams (12.9 oz)) in humans.


Origin Of Deltoid Muscle:
            
              
Deltoid Muscle
Deltoid Muscle Detail


(proximal attachments)
a. Anterior head: anterior surface of the lateral clavicle.
b. Middle head: acromion process and spine of the scapula.


Insertion:

(distal attachments)
a. Deltoid tuberosity of the humerus.



Actions:

Anterior head:
a. Flexes the arm at the shoulder.
b. Medially rotates the arm at the shoulder.
Middle head:
a. Abducts the arm at the shoulder.



 




Nerve supply:

a. Nerve: Axillary nerve
b. Nerve roots: C5 and C6


ACTION OF DELTOID MUSCLE:

  • Abduction Of Sholder ( Middle Fiber )
  • Flextion Of Sholder ( Anterior Fiber )
  • Extension Of Sholder ( Posterior Fiber )

Strengthening Exercise Video On Youtube:




Applied Anatomy Related To Deltoid Muscle:
  
Rupture of the Deltoid muscle
       
Diagnosis: RUPTURE OF THE DELTOID MUSCLE
(Ruptura M deltoideus)

Anatomy: The large Deltoid muscle (M Deltoideus) is a thick triangular muscle, emanating around the shoulder, covering the shoulder joint and forming the rounding of the shoulder. The muscle is fastened on the humerus. The various parts of the deltoid muscle take part in nearly all movements of the shoulder jo
int.

SHOULDER AND UPPER ARM MUSCLES FROM THE FRONT

Cause: When a muscle is subjected to a load beyond the strength of the muscle (butterfly swimming, weight training, weight lifting) a rupture occurs. Most ruptures in athletes are partial ruptures. The rupture can be located both in the front and the back as well as at the attachment to the upper arm (humerus).

Symptoms: In light cases a localised tenderness can be felt following the load (“muscle strain”, “imminent pulled muscle”). In more severe cases sudden shooting pains in the muscle can be felt (“partial muscle rupture”) and in the worst cases a sudden snap is felt, rendering the muscle unusable (“total muscle rupture”) this is very rare, and is almost only seen in conjunction with other damage in the shoulder. With muscle injuries the following three symptoms are characteristic: pain upon pressure, stretching and activating against resistance.


Acute treatment: Acute treatment starts as quickly as possible after the injury has been incurred. The objective of the acute treatment is primarily to prevent additional injury and reduce bleeding as much as possible. Effective acute treatment will reduce bleeding, formation of scar tissue, the number of complications, which can arise, and the rehabilitation period.

Treatment follows the so-called "RICE" principles:

R-   Continued sports activity is immediatel  stopped(Rest)                                               As soon as is possible, Ice should be placed on the injured area. The cold ice makes the blood vessels contract, thereby stopping the bleeding. Cold spray has no effect in such circumstances. The ice must not come into direct contact with the skin, which should be covered with a thin layer of, for example, elastic bandage. Ice treatment should be given for twenty minutes in each of the first three hours after injury.

 I: As far as is possible the treatment should furthermore comprise:                                              

C:   A Compression bandage should be applied, however, must not be so tight as to prevent the blood flow. The compression bandage should be removed at night, but applied again each morning until the swelling goes down. The effect of the compression can be enhanced if a piece of felt, for example, of approx. one cm. thickness is placed under the bandage and directly above the haemorrhaging.                                                                                                                                             
E:  The injured area is kept as high as possible, and preferably above the heart (Elevation). The haemorrhaging will stop when it comes above the level of the heart. Elevation of the affected area should be performed as much as possible as long as swelling is in evidence.



Examination:
Light cases with only minimal tenderness and no discomfort when using the arm do not necessarily require medical examination. The extent of the tenderness is, however, not always a mark of the degree of the injury. In case of more pronounced tenderness medical examination is advised with the aim of securing a correct diagnosis and treatment. Pain will be present when pressure is applied to the damaged muscle, which will be aggravated when the muscle is activated against resistance and when the muscle is stretched. Ultrasound is well suited to ensure the diagnosis.

Treatment: The treatment primarily involves relief, discontinuance of the injury inducing activity, stretching and increasing fitness training.
Electrotherapy Modalities like Ultrasound, Interferential Therapy are used to relieve pain and Tenderness.


Rehabilitation: INSTRUCTION

GENERAL STEP1 STEP2 STEP3 STEP4

Complications : If satisfactory progress is not made, a physician should be consulted to ensure that the diagnosis is correct and that no complications have arisen. Amongst others the following should be considered:
  • Rupture of the upper shoulder blade muscle
  • Inflammation of the upper shoulder blade muscle
  • Rupture of the lower shoulder blade muscle
  • Tendon sheath inflammation of the biceps
  • Sub-Luxation in the joint between the shoulder blade and the collarbone
  • Partial luxation in the shoulder joint
  • Frozen shoulder
  • Muscle infiltrations
  • Sprained shoulder (distorsio art. humeroscapularis)
  • Meniscus lesion in the shoulder (laesio labrum glenoidale)
  • Impingement
  • Nerve entrapment on the back of the shoulder blade