Bones shoulder girdle is a strong foundation for numerous muscles, tendons and ligaments. It's no secret that the top and lower limb- This is human movement, the ability to perform various types of work. In order for the hands to be most developed and functional, a sufficiently solid bone base and strong joints are needed.
Medial epiconditis is a non-articular medial projection of the bony superomort on the troclus. It is more noticeable than the lateral epicondyle. It provides attachment to the ulnar collateral ligament, many of the flexor muscles in the forearm, and the pronator muscle.
The medial supracondylar ridge exceeds the medial epicondyle and forms the sharp medial edge of the distal humerus. The lateral supracondylar ridge is superior to the lateral epicondyle and forms the sharp lateral border of the distal humerus.
The humerus is ossified from eight centers: the shaft, the capitulum and both tubercles, the capitulum and trocelle, and each epicondyle. The shoulder head cannot be mistaken for a head femur, because the former is only half a sphere, while the latter is much larger than half.
Nature has provided for everything in man, so the upper one consists of the scapula, collarbone, humerus, ulna and radius bones, as well as small bones of the hand. Accordingly, muscles are attached to all these bone bases, thanks to which the hand is able to carry out movements.
The humerus is one of the largest and most massive bones in the human body. It consists of a diaphysis, or the tubular body of the bone, and two epiphyses, which are the articular surfaces.
The shoulder shaft is larger and steeper in cross-section than the radial, ulnar, or painter shafts. The humeral shaft is smaller and more irregular in section than the femoral shaft. The humeral shaft is smaller and less triangular than the tibial shaft. For an intact bone, the capitulum faces medially, the capitulum faces laterally, and the olecranon fossa faces posteriorly.
For the isolated proximal end, the head is medial and the lesser tubercle and intertubal groove are anterior. For the isolated distal end, the olecranon fossa is posterior, the medial epicondyle is larger, and the capitulum is lateral and oriented anteriorly. If the articular end is absent, the coronoid fossa is larger and more medial than the radial fossa.
If you take a closer look at the anatomy of this formation, you will notice how functionally thought out this bone is.
Like any surface, the humerus has a weak point - the surgical neck; this is where the bone most often breaks. However, the muscular frame is designed in such a way that when physical activity it is in this place that it grows most intensively muscle mass, thereby protecting the bone.
For an isolated fragment of the shaft, the deltoid tuberosity is lateral, and its posterior arm extends from the bed all the way to the anterior one, and the nutrient foramen emerges from the bone towards its proximal end. A small thin ridge runs along the entire medial edge of the shaft, and on this edge there is an opening for nutrients. The lateral lip of the intertubular groove is stronger and longer.
Endoscopy allows for a thorough examination of the infected bursa, as well as a means of copious lavage and removal of adhesions. Synovial resection should be considered; however, is controversial in cases of septic arthritis. The bursa is distended with 100 ml of lactated Ringer's solution as previously described. When the distended bursa is inserted and fluid leaks from the cannula, the obturator is removed and replaced with an arthroscope. The portal site is predetermined by placing a spinal needle at the proximal aspect of the bursa, lateral to the biceps tendon.
In addition, the humerus has several projections, or tubercles, to which the largest muscles of the shoulder are attached. Ridges or elevations extend from the protrusions, between which the intertubercular groove is located - this is where the tendon attaches
In the area of the lower epiphysis there are two condyles, and above them two epicondyles - these are also peculiar bone tubercles, which are part of this. There are also two fossae - the ulnar and coronoid, they are necessary for a more dense comparison of the processes of the ulna and radius.
The bursa is examined and any foreign debris or adhesions are removed. Endoscopy of the intraspinal bursa has also been described. 41 The horse is placed in the lateral integumentary area and ultrasonography is used to identify the cranial aspect of the bursa, where needles are inserted by the cranial tendon into the infraspuncture and 1 cm distal to the greater tuberosities. The bursa is stretched and an arthroscope is inserted into the area. After arthroscope placement and further distention of the bursa, the instrument portal is identified with needle placement and positioned in the caudal bursa.
The humerus is a rather complex structure, and in addition support function will also perform a number of others. For example, hematopoietic. As you know, everyone is an organ that produces red blood cells. In the spongy substance of the bone is located which performs this function.
In addition, cancellous bone is capable of producing factors that influence immune system and blood clotting.
Minimal manipulation is possible in the bursa other than careful exploration and extensive fishing, and the incisions can be converted into an open approach to remove fragments of the larger cusp. The type and duration of use of antimicrobial and anti-inflammatory drugs depend on the presence or absence of sepsis. Likewise, postoperative rehabilitation and return to learning or performance are related to the degree of tendinitis or bursitis.
The deltoid muscle is a large, triangular, limb-shaped, thick muscle that gives the shoulder its shape and contour. The deltoid is the primary abductor of the arm and also flexes and extends the humerus. The deltoid is the largest and probably the most important muscle shoulder complex. These parts cover top part humerus, converge to a thick tendon to insert onto the lateral surface of the humerus bone.
It should be noted that the size and diameter of the bone is individual for each person. This depends on growth, the amount of nutrients supplied and on hereditary predisposition. Often we have to deal with a situation where patients have increased fragility or fragility of bones due to a deficiency of calcium and other microelements. This process can be formed in utero.
All three sections differ in structure and function, but work together to produce important movements in shoulder joint. The deltoid is also an important dynamic stabilizer of the glenohumeral joint, but this action has not been as widely studied in its movements. It appears to provide anterior stability while compressing the humeral head against the fossa for 90° and external rotation. Since the true plane of abduction corresponds to the blade of the scapula, the deltoid is said to provide dynamic stability during abduction in the “scapular plane.”
Shoulder fractures are common in young children school age and older people. This is due to the lifestyle of the former and a decrease in physiological strength in the latter case.
During a fracture, the humerus is destroyed at its weakest point - in the area of the surgical neck, but there are other types of fractures. In children - a subperiosteal fracture of the “green stick” type, and in adults, fractures with displacement of fragments.
However, it reduces stability in the coronal plane, where it tends to cause upward shear or traction on the head of the humerus, leading to damage to the acronium. The rotator cuff, namely the subscapula and petit, produce a synergistic downward movement to compensate for this upward shift of the humeral head. In other words, the rotator cuff sleeves are very important in stabilizing the humeral head while balancing this force by resisting upward shear of the deltoid.
There are still many questions about the role of the deltoid in dynamic stability versus its role as a destabilizer, and much of the evidence is contradictory. However, it is clear that the deltoid, acting on its own, will not be able to function normally as the rotator cuff is the primary means of keeping the shoulder head centered in the skeletal fossa during most daily functional movements and tasks of the shoulder.
In any of these situations, the patient needs qualified help.
Osteosynthesis of the humerus can be performed in several ways. There is a special one that allows you to fasten existing fragments. The insertion of wires can be carried out at absolutely any level and near the joints. The difficulty is in inserting the needles in the area of the upper third of the shoulder on the inner surface (in the axillary region), because this brings discomfort and inconvenience to the patient, so in this area the needles are inserted in an X-shape.
Glenohumeral hinge. The deltoid is active during any lifting and remains static during most daily tasks. However, it is important that the muscles, however, are important, the smaller muscles of the rotator cuff, as mentioned above, must also be taken into account in its actions, with the supraspinatus playing important role during the abduction.
The deltoid is activated for long periods of time while typing and driving. If the keyboard or work surface is set too low or too high, this activation increases. Driving with your hands at the top of the steering wheel primarily activates the front deltoid. Trigger points can develop due to overuse of these mechanisms or due to the abuse that muscles often receive in resistance training, as many bodybuilders and strength training They devote entire workouts to just the shoulder.
In order to most correctly align the fragments, you can use the skeletal traction method before placing the apparatus.
Traumatologists often use special plates and screws for osteosynthesis of the humerus if the area of damage is not too large and the number of fragments does not exceed 3-4 pieces.
In the upper part the body of the humerus is rounded, and closer to the distal epiphysis it is triangular. On the body there are: posterior surface (lat. facies posterior), limited by the lateral and medial edges (lat. margo lateralis et medialis); medial anterior surface (lat. facies anterior medialis) and lateral anterior surface (lat. facies anterior lateralis), which are separated by an inconspicuous ridge.
Trigger points cause pain in the deltoid muscle itself, which feels like deep shoulder pain. Trigger points can also develop after direct injury to a muscle during sports. Functional characteristics The deltoid and supraspinatus become much more complex during athletic movements such as throwing or sports that require shoulder abduction and external rotation. The rest of this article will only cover basic movements as long as the athletic function is within its scope.
Deltoid muscle: origin, insertions and actions
Anterior fibers: anterior and upper surfaces outer third of the clavicle and anterior acronium.
- Medium fiber: lateral edge of acronium.
- Posterior fibres: inferior border of almost scapular spine.
The proximal epiphysis is represented by the head of the humerus (lat. caput humeri), separated from the diaphysis by an anatomical neck (lat. collum anatomicum). The head articulates with the glenoid cavity of the scapula, forming the shoulder joint. Behind the neck there are two tubercles (apophysis) - the larger and the smaller (lat. tuberculum majus et minus), between which runs the intertubercular groove - the site of the tendon of the long head of the biceps brachii muscle. Below the tubercles, at the border with the diaphysis, there is a surgical neck (lat. collum chirurgicum) - the site of the most common fractures of the humerus.
The three parts of the deltoid can contact independently or together, depending on the action. The actions of the deltoid and its three parts will be considered first from the point of view of the primary actions of each group of fibers, and then again by movement together with the synergists.
Contraction of the entire deltoid with all its fibers results in abduction of the shoulder joint, but the middle fibers are usually considered only abductors. When all the muscles contract, it can cause the shoulder to abduct just below 90 degrees without scapular rotation, which must occur for full abduction to occur. The lateral deltoid fibers have a multi-band arrangement that gives it more strength over a short range of motion than the anterior and posterior fibers, which are spindle-shaped and better suited for high speed over a long range of motion. Contraction of the anterior fibers only results in adduction, flexion, and internal rotation. Forward flexion and internal rotation of the humerus is carried out in combination with pectoral muscle. Contraction of the posterior fibers only results in adduction, extension, and external rotation. Lengthening and external rotation of the humerus is performed in combination with retisimus dorsi and major. The deltoid, together with the supraspinatus, contracts when carrying heavy objects laterally to resist the strong downward thrust. The deltoid is also actively involved in positioning the arms for everyday manual tasks by creating forward flexion of the humerus. However, some of these fibers are active in flexion. . These are the primary shoulder movements in which the deltoid is active along with its synergists.
On the body of the bone there is a deltoid tuberosity (lat. tuberositas deltoidea), to which the deltoid muscle is attached. Posterior to the tuberosity, a groove runs in a spiral from the medial to the lateral side radial nerve(lat. sulcus nerve radialis) .
Delta Trigger Points Causes and Symptoms
Note that a synergist can have more than one type of role. For example, some synergists may be stabilizers during a given action, while others may have a redundant role or act as neutralizers. As stated above, trigger points can be activated in the deltoid by impact trauma such as a direct blow or a fall on the shoulder; or overuse of a muscle. Additionally, any accident that injures the deltoid muscle, such as reaching to catch yourself while falling, can activate trigger points.
On the distal epiphysis there is a condyle (lat. condylus humeri) and on the sides of it there are two epicondyles - medial and lateral (lat. epicondylus medialis et lateralis ). Between the epicondyles there is a surface for articulation with the bones of the forearm, divided into a block of the humerus (lat. trochlea humeri) and the head of the condyle of the humerus (lat. capitulum humeri). Above them on the front side, respectively, are the coronal (lat. fossa coronoidea) and radial (lat. fossa radialis) fossa, as well as behind the ulnar fossa (fossa of olecranon, lat. fossa olecrani), which are necessary for articulation with the ulna and radius, forming the elbow joint. On the posterior side of the medial epicondyle there is a groove for the ulnar nerve (lat. sulcus nerviulnaris) .
However, unlike most other trigger points, deltoid trigger points do not refer pain to a distant area. Continuous shoulder pain most likely comes from some other underlying pathology or trigger points in other muscles that refer pain to the shoulder area.
For example, constant dull ache in the shoulder most likely causes points in the rotator cuff muscles. When the shoulder joint experiences pain during passive mobilization with scapular rotation and elevation, as opposed to active shoulder movements, it most likely indicates a sprain or subluxation of the acromioclavicular joint, the pain pattern of which mimics pain at the anterior deltoid trigger points.
Ossification
By the time of birth, only the proximal epiphysis consists of cartilaginous tissue, which is why the head of the humerus is practically undetectable on radiographs. During maturation, three points of ossification of the proximal epiphysis appear successively:
- In the medial part of the head of the humerus (0-1 year or from birth);
- In the greater tubercle and in the lateral part of the head (2-3 years);
- In the lesser tubercle (3-4 years);
By 4-6 years, these centers merge into a single head of the humerus. Replacement of metaepiphyseal cartilage at the border of the proximal epiphysis and diaphysis bone tissue(synostosis) occurs in adolescence, due to which the bone continues to grow in length. An x-ray of a child or teenager reveals a characteristic light area at the site of the metaepiphyseal cartilage, which can be mistaken for a fracture or fissure.