The sternoclavicular joint is not always clearly visible. It usually manifests itself in people who are underweight or asthenics. If there is a small amount of subcutaneous adipose tissue, it can be considered. In people with normal or increased body weight, it is visually indistinguishable. On palpation, they are guided by the clavicle bones, between which, at the junction with the sternum, below the cervical fossa, there are two symmetrical sternoclavicular joints.
Definition and location of the joint
The sternoclavicular joint – is the junction of the clavicle with the sternum. It has an asymmetrical shape, which allows you to compensate for the difference in size and shape of the bone notch and collarbone, allowing them to perfectly match each other. Inside the joint is the articular disc, which compensates for the pressure between the bones, being a connecting element. From above, the entire connection is covered with cartilage, protecting it from external influences and damage.
Sternoclavicular joint. Feature
The purpose of the joint is to connect the upper limbs with the chest by combining the bones of the clavicle and shoulder girdle withtorso. By its origin, the sternoclavicular joint – is a rudiment that is a connection of the upper or forelimbs not only in humans, but also in animals, starting with reptiles. It is very strong and participates in the movement of the hands, the reformation. This is especially felt when raising your hands up and down. This connection allows the clavicle to move along three main axes, synchronized with the shoulder joint, supported by a powerful and very strong ligamentous apparatus.
Building
The sternoclavicular joint is shaped like a saddle joint. According to its structure, it has a communicating shape, having concavities and convexities corresponding to each other. This joint, having two axes and freely moving along them, from the point of view of simple mechanics, is a universal joint. Its structure includes the following cartilaginous tissues:
- cartilaginous covering of the clavicle;
- cartilaginous covering of the sternocostal cavity;
- cartilaginous disc;
- cartilage covering the joint.
Thus, the structure of the joint includes:
- medial end of the clavicle with its main surface;
- upper bundle;
- front ligament;
- costoclavicular ligament;
- back link;
- concave arches of the sternocostal surface.
Also support the sternoclavicular joint:
- Intervertebral ligament stretching over the notch of the jugular cavity of the sternum between the ends of the clavicularbones.
- Sternoclavicular ligament complex. According to their location, they converge on the anterior, posterior and upper surfaces of the joint, strengthening its strength.
- The most powerful and durable ligament in the sternum is the costoclavicular ligament. It runs from the very top edge at the first rib and rises to the collarbone. Controls the maximum elevation of the collarbone.
The sternoclavicular joint, having a saddle-shaped structure, resembles spherical ones in terms of the possibilities of its movement.
Damage
Due to its superficial location and role in movement between the bones and joints of the shoulder girdle and trunk, the clavicle itself and the joints attached to it are often subject to fractures and dislocations. Dislocation occurs as a result of sharp movements of the shoulder girdle backwards or downwards and backwards. In this case, the anterior ligament is torn, forming a subluxation. With a stronger impact on this joint, all ligaments are torn, releasing the clavicle from the articular fossa, forming a dislocation of this joint, which is easily recognized by external signs. Another type of dislocation occurs if the impact on the collarbone and joint is direct, that is, by a direct blow or strong pressure when the posterior ligament is torn. This dislocation occurs inside the chest. The same happens when the joint is affected by a strong compression of the shoulders forward and inward. As a rule, with such impacts, a fracture of the first or first four ribs of the sternum is also observed.
Diseases
This joint is characterized by suchdiseases such as ankylosis, which is a consequence of gonococcal or rheumatoid arthritis. After the age of forty, arthrosis often appears, which during its course forms marginal osteophytes on the head of the clavicle. Soreness caused by exposure to the sternoclavicular joint, crunching, swelling should be the reason for a visit to an osteopath.
Aseptic necrosis of the end of the clavicle attached to the sternum, which is better known as Friedrich's syndrome, is determined by palpation. It causes a painful swelling of the tissues around the joint, swelling and redness of the skin. Hyperostotic changes in the attached end of the clavicle are manifested in marble disease (Paget's disease). The manifestation of hyperostosis is typical of congenital syphilis.
Diagnosis of changes in the joint
Methods for diagnosing diseases and disorders in the sternoclavicular joint are examination and palpation, X-ray of the bones of the chest. All studies are carried out by a traumatologist or osteopath. The presence of any asymmetry or deformity, redness or pain during movement in the sternoclavicular joint, the appearance of a crunch in movement indicate the presence of one of the above diseases or injuries.
Palpation is performed with the second and third fingers of the right hand, while the doctor is located behind or to the side of the patient. The fingers are placed in the middle of the sternum and focusing on the recessunder the neck of the patient, feel for the joint. For better detection of his patient, he is asked to raise his arms in a horizontal plane, which greatly facilitates the search.
The sternoclavicular joint is simple in structure. But at the same time, he is quite strong, keeps the limbs attached to the body. When this joint is damaged, arm movement becomes very limited and painful.
