Anatomy of the shoulder joint. Structure and function of the shoulder joint

The shoulder joint, whose anatomy is discussed in the following article, allows the hands to move freely. Bundles, on the contrary, limit mobility.

We will study in detail what the shoulder joint is, the topographic anatomy of which is represented by the mutual arrangement of tissues, nerves and vessels.

In the shoulder girdle, the joints unite the clavicle and the sternum with the scapula, due to which the acromioclavicular and sternocleid joints are formed. Let's start in order.

Bones

Anatomy of the shoulder joint is complicated. To ensure the mobility of the cavity here is conceived less, and the volume of movement is provided by a multitude of tendons and muscles.

The joint consists of two large bones - the shoulder and scapula, several joints and a multitude of ligaments, tendons and muscles.

The blade is a flat bone in the form of a triangle. It is also important in the construction of the articulation of the shoulder joint. The bone is located on the back of the body and is easily felt under the skin. It has a joint cavity to which the humerus is attached .

On the back side of the scapula is an axis dividing it in two, where subacute and supraspinous muscles are located.

On the scapula there is another process, called the coracoid, attaching ligaments and muscles. Another bone - clavicle - is tubular, with a curved shape.

The entire shoulder joint (anatomy) of the photo below illustrates.

Muscles

Rotating, or rotator, cuff is one of the most important articulations of muscles in this part. Muscles help to bring, bend and unbend the arm.

Injuries in this area are most often associated with the cuff. The athletes are particularly at risk. However, troubles happen in the home, especially when lifting weights and carrying the load without distributing the weight correctly. If the muscles are damaged, the anatomy of the shoulder joint is broken. Muscles then can not promote movement as before, and the amplitude is sharply reduced.

So, the cuff consists of:

• Supernatural;
• Subacute small round;
• Subscapular muscle.

Blood supply and innervation

Muscles of the shoulder girdle receive blood from the axillary artery and its branches. It crosses the underarm cavity and moves from the first rib to the bottom of the large pectoral muscle, passing into the brachial artery. She is accompanied by a vein.

Innervation is realized through the nerves of the brachial plexus. It involves both spinal cord and the anterior branch of the thoracic nerve. The brachial plexus originates from the base of the neck, moves forward and downward, penetrating into the cavity of the armpit, goes under the clavicle, under the beak-like process of the scapula, giving there nerves.

Due to what is the movement?

The shoulder joint can move through the following five joints (three joints and two - the muscle-tendon plan):

1. Shoulder-scapular joint.
2. Full-time education.
3. Move the scapula along the chest.
4. Acromioclavicular joint.
5. Breast-clavicular joint.

Look at the photo. Here is represented the shoulder joint: structure, anatomy. The complex structure of this area is best understood for understanding by analyzing the image.

To ensure a full-fledged motion, all five joints must work smoothly and correctly. Any violation can not be replaced by other joints. This is why pain and movement restriction always accompany damage to this area.

Acromioclavicular joint

Anatomy of the shoulder joint is characterized by multiaxiality and a plane, due to which the collarbone merges with the scapula. It is held by a strong beak-clavicular ligament, directed from the coracoid process of the scapula to the bottom of the clavicle. The scapula is able to rotate around the sagittal axis, which passes through the joint, and also moves slightly around the transverse and vertical axes. It turns out that the movements in this joint can be made around 3 axes. Nevertheless, the amplitude here is very small.

Breast-clavicular joint

The anatomy of the shoulder joint here is also represented multi-axis and flat. The surface consists of the sternal part of the clavicle and the clavic notch of the sternum. The shape of the surface of the joints resembles a saddle. Between them is a disk that fuses with a capsule and divides the joint cavity in two. A thin capsule is attached by ligaments woven into the fibrous membrane from both sides. In addition, there is an interclavicular ligament that connects the sternal ends of the clavicles, as well as costochondral, clavicle, located in the lateral position in a small distance from the joint.

Anatomy of the shoulder joint is represented by three axes. It has a rather limited amplitude. Therefore, they can be moved forward, backward and rotate a little. A circular motion can be made when the end of the clavicle makes an ellipse.

Ligament bundles

In addition to the joints, there are fibrous bundles on the upper limb belt - these are the bundles of the scapula. They consist of the lower and upper transverse, and also beak-acromial. The latter is represented in the form of a triangle, where the arch is stretched over the shoulder joint between the coracoid process and the apex of the acromion. The ligament serves as a protection for the shoulder joint and, together with others, limits mobility when leaning the shoulder. The lower transverse is located between the edge of the articular cavity of the scapula and the base of the appendage of the shoulder, and the upper transverse ligament is tossed through the scapular notch.

Structure and ligaments of the shoulder joint

In the free part of the limb joints are fused together and the belt of the upper limb, due to which the wrist, ulnar, brachial and other areas are formed.

The shoulder joint has a multi-axis and spherical structure. It consists of a bone head and a scapula cavity. The surface of the first is spherical, and the second has the appearance of a pit. The head is about three times larger than the cavity, which is complemented by the lip of the joint. The latter increases its surface a little, adding depth, curvature and congruence.

Capsule of the joint is large, but thin. It originates at the lip and is attached to the neck of the humerus. Inside the capsule is thrown between the humerus of the humerus and forms the intercampum synovial vagina. The capsule is fixed by the beak-brachial ligament, directed from the scapula of the scapula and interlacing into it.

Features of motion

In the ligament of the shoulder joint anatomy is characterized by underdevelopment. Due to the considerable difference in the contiguous surfaces in the shoulder joint, a large amplitude of motion is possible with respect to the three axes: vertical, sagittal and transverse. Around the sagittal shoulder it is removed and brought, around the transverse one - it bends and unbends, and the vertical arm turns inward and outward.

In addition, the anatomy of the shoulder joint allows you to make circular motions. They in this area can occur together with the belt of the upper limb. As a result, it is able to describe to a greater or lesser extent the hemisphere. But the removal of it above the level horizontally stops the large tubercle of the humerus.

It is necessary to know that the removal of the hand, thanks only to the operation of the humerus and the articular cavity, is only brought to ninety degrees. Then the blade starts to help the movement, due to which the lead is increased to 180 degrees.

Not only problems in the muscles and tendons of this region lead to destabilization of the condition of the upper limb. They can cause deformity of the chest or abnormalities in the spine. Therefore, it is so important to pay attention to your health and pay attention to symptoms in a timely manner. Then it will be possible to maintain health and a full-fledged movement for life.

Diseases and anatomy of the shoulder joint, MRI

With pain in the shoulder, it is necessary to consult a specialist to make the correct diagnosis. The condition of the bones will help to know the X-ray. Soft tissue and cartilage are studied after ultrasound. An excellent and safe way is MRI. Anatomy of the shoulder joint can also be viewed with the help of arthroscopy, which, in addition to diagnosis, also treats the patient.

Consider the most common diseases.

Bursitis

The disease is diagnosed with inflammation of the curvature of the synovial shoulder bag. Anatomy in this part is very complicated. Usually, the lesion occurs between the bone and the tendon. The peculiarity of the bursitis of the shoulder joint is that the synovial bag here does not communicate with its cavity.

The causes of bursitis can be both traumas and infections, as well as excessive stresses on the joint in athletes and workers engaged in heavy physical labor.

Pleuropedal periarthrosis, or periarthritis

This is also a frequent condition with pain in the shoulder area. This includes a whole group of the following diseases.

• Osteochondrosis develops in the cervical spine. Pain spreads through the nerves and passes into the brachial plexus. Then the so-called plexite develops. The method of treatment is chosen depending on the state of nerve endings, as well as intervertebral discs.
• Subacromial impingment - a syndrome characterized by squeezing the shoulder rotators, which pass between the head of the shoulder and the scapula of the scapula. The channel may be squashed or injured. Then a person will feel pain, especially at night. He can not lie on his shoulder, bend his hand and take her away. During treatment, anti-inflammatory drugs are selected, and physiotherapy procedures are also prescribed. Used ointments, massage, compresses and gymnastics. If necessary, a surgical operation is also prescribed.
• The cuff rupture results from injury, squeezing or stretching. The tendon is rubbed. The shoulder begins to hurt, and the pain gives in the hand, because of what it can not be bent and removed. When a rupture is required, an operation is performed where the tendons are stitched through arthroscopy. In this case, the main thing is not to miss the optimal time, the result will be better the earlier the problem is clarified and eliminated.
• When the joint capsule is stuck together with inflammation, an adhesive capsulitis is diagnosed. The patient is less able to move his hand. If there is no arthroscopic surgery, then in the future, the only option for returning mobility will be prosthetics.
• Because of the chronic stretching of the muscle and tendon under the shoulder blade, as well as trauma, the "frozen shoulder" syndrome develops. At the same time, pain and limited or inability to take your hand out is felt. To relieve the patient of suffering, the affected area is treated with an anesthetic.
• As a result of the injury, the cartilaginous lip may be damaged and a rupture may occur. Restoration is possible with the help of arthroscopy.

Prosthetics

To replace damaged by trauma or disease, the surface of the shoulder is prosthetic. Anatomy of the articular cavity remains unaffected. Establish an artificial implant only in cases when other methods of treatment are ineffective.

So, it becomes the only solution after the fracture, when the anatomy of the shoulder joint and the muscles of the shoulder can not be restored and the metal retainer is useless.

Prosthetics will also be required at the advanced stage of osteoarthritis. Damage to the cartilage is accompanied by pain, crunching and limited movement. Patients become helpless. At the same time, prosthetics restores the work of the hands, and the person gets rid of the pain.

The same applies to damage to the muscles of the rotator cuff. If at the beginning of the disease an effective method of treatment is arthroscopy, then later, in the neglected version, it will be powerless. Therefore, an implant is installed.

Also, a serious form of a disease such as rheumatoid arthritis is dangerous. The surfaces of the joint are destroyed, the muscles of the rotator cuff and other soft tissues are damaged, severe pain is felt, and movement is limited and gradually leads to immobilization.

Whatever manipulation on the joint is not carried out, after them the hand must be fixed with the help of an orthosis, bandage or bandage. To ensure the functioning of the upper limb has returned to normal, a complex treatment is carried out, implying different restorative measures. These include special training, massage and physiotherapy.