Shoulder muscles. Muscles of the forearm: anatomy Pronator teres origin and insertion

Start from shoulder girdle and shoulder, are attached to the bones of the forearm.

1.Anterior muscle group (flexors):

Biceps brachii muscle (Produces flexion at the radial and elbow joints, supinates the forearm.)

Brachialis (flexes the forearm.)

Beak-shaped – brachialis muscle(attaches to the humerus) (Bends the shoulder and pulls it toward the midplane.)

2. Posterior muscle group (extensors):

Triceps brachii (Extends the forearm at the elbow joint.)

Elbow muscle (Extends the forearm at the elbow joint.)

Forearm muscles:

The muscles of the forearm surround the radius and ulna on all sides, most of them being long muscles. The muscle bellies of such muscles are located proximally, the long tendons are located distally. Most of the flexors originate from the medial epicondyle humerus, and most of the extensors come from the lateral epicondyle of the humerus. The muscles of the forearm are attached to the bones of the metacarpus and the phalanges of the fingers. They act on the wrist, proximal and distal radioulnar joints, and hand joints. Bend and straighten the wrist and fingers.

1. Anterior muscle group (flexors and pronators):

Surface layer:

Brachioradialis muscle (Flexes the forearm and sets the radius in a mid-position between pronation and supination.)

Pronator teres(Pronates the forearm and participates in its flexion.)

Flexor carpi radialis (Produces palmar flexion of the hand.)

Flexor carpi ulnaris (Bends and adducts the hand.)

Palmaris longus muscle (Bends the hand, strains the palmar aponeurosis.)

Deep layer:

Superficial flexor of the fingers (Bends the middle phalanges of the II-V fingers and the hand.)

Long flexor thumb(Bends the distal phalanx of the thumb.)

Flexor digitorum profundus (Bends the distal phalanges of the fingers.)

Pronator quadratus (Rotates the radius inward.)

2. Posterior muscle group (extensors and supinators):

Surface layer:

Extensor carpi radialis longus (Extends and abducts the hand.)

Extensor carpi radialis brevis (Extends the hand.)

Extensor digitorum (Extends fingers II-V.)

Extensor of the little finger (Extends the fifth finger.)

Extensor carpi ulnaris (Extends and adducts the hand.)

Deep layer:

Arch support (Rotates the radius outward.)

Abductor pollicis longus muscle (Adducts the thumb.)

Extensor pollicis brevis (Extends the thumb.)

Extensor pollicis longus (Extends the thumb.)

Extensor index finger (Extends the second finger.)

Muscles of the hand:

Muscles of the eminence of the thumb (Lateral group. Functions correspond to the name of the muscles.)

Abductor pollicis brevis muscle

Flexor pollicis brevis

Muscle that opposes the thumb to the hand

Adductor pollicis muscle

Muscles of the eminence of the little finger ( Medial group. The functions correspond to the name of the muscles.)

Abductor digiti minimi muscle

Flexor digiti brevis

Opponus little finger muscle

Muscles of the palmar cavity ( Middle group. Functions: vermiforms bend the proximal phalanges of the II-V fingers; palmar interosseous brings the fingers together; the back fingers spread apart.)

Vermiform muscles

Palmar and dorsal interosseous muscles

Recently, the study of the movement of the human body from the point of view of biomechanics has become very popular. This is a holistic, holistic approach that views the body as a whole, rather than individual parts.

Science that studies the body

In this regard, the concepts of “fascia” and “myofascial chains” also appeared. The science that directly deals with the health of the human body is called kinesiology. From “kinesio” - movement, “logos” - to study. That is, she studies the patterns of body movement.

This may be applicable in sports, in the treatment of pathologies, massage therapists and chiropractors may be interested in this. There are not many kinesiologists, but more and more modern doctors - osteopaths, neurologists - are interested in this area.

Pronation and supination: what does it mean?

Let's look at some of the terms used by kinesiologists and their explanations. Rotation, pronation and supination are types of movement of the limbs and shoulder joints in kinesiology.

Pronation is the turning movement of the upper or lower limbs inside. This may include movement of the hand, forearm and humerus. As well as the foot, lower leg and femur.

Let's look at the example of a hand. If you stretch your hand forward so that your thumb is on top, and then rotate it 90 degrees inward so that your palm becomes horizontal position, such a movement will be pronation. This type of rotation is performed by a group of muscles called pronators.

In the same way, supination is performed by muscles - supinators. Only in this case is the lateral edge turned outward, in the opposite direction.

Pronation of the foot

Let's take a closer look at what it is - pronation of the foot? You can also pronate your foot separately. In this case, it is necessary to turn it, lowering the medial part down (inward, towards the central axial line of the body). The pronator muscles of the lower extremities are involved. Pronation of the foot involves the peroneus longus and brevis muscles.

Supination - turning outward of the lateral part of the foot (outward, outward from the center line of the body) of the lower or upper limbs. The principle is the same as in pronation, only the movement is in the opposite direction. It is carried out by a group of muscles - supinators: extensor longus thumb and anterior tibial.

Features of gait and shoes

Perhaps many have noticed how some people walk “clubfooted”, that is, they have weak arch supports, and the foot falls inward. Or, conversely, a Chaplin-style gait indicates weakness of the pronators. It should be noted that these muscle groups are antagonists. Antagonists are groups that are opposite in their biomechanics, designed together to balance each other, keeping the limb in a central position.

Pronation and supination - this concerns the upper limbs and is very different from the same movements of the lower limbs. This is due to the structure and mobility of articular and tendon structures. There are three ways to place your foot when walking or running:

1. With normal pronation. It can be easily identified by the footprint of a foot in wet sand or a wet foot on paper or the floor. The imprint will be characteristic, curved outward. An imprint is not formed at the instep of the foot; it should be understood that this is normal pronation of the foot.
2. With overpronation. In this case, the person becomes as if turning his foot inward; this is typical in the presence of flat feet. The imprint of such a foot is wide, almost not curved, the instep is either minimal or absent at all. In this case, the sole of the shoe will wear off from the inside (especially the heel). The foot, “piled” inward, twists the remaining parts of the leg in a chain, creating rotation of the knee joint and greater trochanter of the femur. Which leads to wear and tear of the articular surfaces. Strong pronation of the foot is, in fact, flat feet.
3. With hypopronation. This means weakness of the pronators and inversion of the foot. Also, the gait of people with hypopronation is special - they seem to throw their socks out, and the outer side soles of shoes, especially heels. Knee-joint at the same time it also rotates, creating pathology, and femur also turns out slightly.

People with pronation problems should consult with an orthopedic doctor or kinesiotherapist and choose the best shoe option for themselves. The sole should not be thin, the heel part will be reinforced and have a small heel. In case of hypopronation, doctors often recommend wearing special inserts and insoles - arch supports. This is done so that disorders from the foot do not rise up the muscle chains and do not cause arthritis and arthrosis of the joints due to compensatory rotation.

Shoulder

Pronation and supination are two types of movements that also affect the shoulder. Differs in biomechanics from other parts of the body and depends entirely on the structure shoulder joint- one of the most complex in its biomechanics. It is produced by moving the shoulders inward (pronation) and moving the shoulders back (supination). The pronators and supinators of the shoulder girdle are designed to maintain posture, straight position of the upper back and are also opposite in their biomechanics (antagonists).

The following muscles work in pronation (inward rotation) of the shoulder: pectoralis major, teres major, latissimus dorsi and subscapularis.

The muscles involved in supination (outward rotation of the shoulder) are the infraspinatus and teres major.

Rotation

Rotation is another type of movement and it means "turning". It is inherent not only to the limbs of the human body, but also to some constituent elements, for example, vertebrae. Pronation and supination can be considered incomplete rotation. The range of motion of the upper and lower extremities is very different, which is important to remember. Any rotation is designed to stabilize parts of the body during movement.

The rotator muscles (pronators and supinators) are small and unremarkable in the general relief of muscle mass. But athletes need to be told about them; the coach must convey to beginners the importance of antagonists for building body composition.

Use in bodybuilding

In bodybuilding, the use of pronation and supination is popular, this is important, for example, when lifting dumbbells. When working with free weights, an athlete can use different groups muscles. Pronators and supinators must be inflated evenly. Visually these are the muscles of the forearm and lower leg. If you don’t do this, then the bodybuilder will have his arms spread out to the sides while walking, and his legs will “throw out” in a funny way.

The pronators and supinators of the shoulder, as antagonists, can either ruin posture or improve it. Therefore, a bodybuilder needs to pump up both pectoral muscles, and back muscles. Sometimes an athlete’s shoulders seem to be turned forward, this indicates stretching of the rhomboid and infraspinatus muscles, while the pectoralis major, on the contrary, is severely spasmed. This can cause numbness in the fingers and pain in the attachment points of the pectoralis major muscle.

Raising the forearm with supination

Lifting dumbbells with supination is carried out with the hand turned outward. The supinators are trained: short supinator and biceps muscle (biceps). The biceps muscle becomes stronger when the elbow is bent to 90 degrees. We perform rotation of the forearm with supination while working with a screwdriver, for example, or unscrewing a tap.

Thus, the supinated biceps curl trains additional muscles and stabilizes the forearm, making it strong. This is especially important in arm wrestling.

The pronators include: pronator quadratus and pronator teres. They are much weaker than their antagonists. When a person finds it difficult to unscrew a bolt that is twisted crookedly, he uses more force and uses inward rotation of the shoulder (shoulder pronation). The brachioradialis muscle acts in this case as a pronator, although initially this function is not inherent to it. Initially, the brachioradialis muscle is a flexor of the forearm.

A harmonious body structure is the goal of muscle development, so it is necessary to take into account the role of pronation and supination for both professional athletes and beginners.

Hello friends! Today we will look at the anatomy of the forearm muscles. The muscles of the forearm are most often exposed throughout the year, so we do not want to leave them in a frayed state.

Forearm- this is the part of the arm that is located between the ELBOW and the WRIST.

The fact is that our forearms are made up of a HUGE amount of small muscles.

Nature did this so that we could perform various kinds of manipulations with the objects around us, and, precisely for this, we need to have very different mobility of the forearms, which is achieved only by the variety of muscles that perform these movements.

As always, I only focus on the BIGGEST muscles by size.

Why do we need to train those muscles that, in principle, give very little growth, both in terms of size and appearance?

After all, when you do squats, you are doing them to develop your quadriceps, hamstrings and gluteal muscles, and not to pump up the adductor muscles.

This is true in terms of costs training process and obtaining the corresponding result.

This is why many beginners make the mistake of only starting to train their biceps and abs when they first get to the gym. As a result, they make much less progress than those beginners who worked on their legs, chest and back in their first years of training.

Movements performed by the muscles of the forearm

All movements performed by the muscles of the forearm can be divided into FIVE CATEGORIES:

• EXTENSION of the forearm(posterior muscle group, triceps side).
• FOREARM FLEXION(anterior muscle group, biceps side).
• SUPINATION of the forearm(muscles that externally rotate the forearm).
• PRONATION of the forearm(muscles that internally rotate the forearms).
• Squeezing the forearm(muscles that clench your fingers into a fist).

It is important to take into account the FOREARM BONES, because their structure allows us to move in different vectors, and therefore use different exercises.

Inside the wrist there are not one, but TWO IMPORTANT BONES - the RADIO and ULNA, which are connected to each other by means of ligaments and muscles.

This anatomical structure makes it possible to move radius around the elbow in a circle. This is the so-called "supination" and "pronation".

The muscles that perform these movements can be developed, so they will give additional volume to the forearms.

IMPORTANT: the muscles of the forearms are on “different floors”. Some of them are closer to the skin, and some are closer to the bones. We have already encountered muscles that are located in several layers, in.

Forearm muscles: anatomy

The forearm muscles are a very intricate chain of a huge number of different muscles.

It must be said that most of these muscles simply complement the work of one main muscle, and, as you understand, these “secondary muscles” synergists provide a smaller increase in volume.

Therefore, we will develop exactly those muscles that will be best suited for growth.

1. Brachioradialis muscle(from the English “brachiordialys”) is the MOST BIG muscle forearms. It BENDS the forearm, and also takes part in pronation and supination of the forearm (rotates the forearms in and out). When bending your arms reverse grip(overhand grip) the brachioradialis muscle is the SECOND most important muscle after the brachialis.
2. Flexors of the hand (radius and ulna) – these muscles are located in the inner part of the forearms (on the biceps side) and are responsible for moving the hand towards the arm. This function is the main one. Additional function: pronation of the hand (turning outward).
3. Extensor carpi radialis – this muscle is located on the triceps side, which extends the hand outward (towards the elbow). Those. extends the hand at the wrist joint.
4. Pronator teres carpi – this muscle is located on the “lower levels of the forearms.” It is attached next to the elbow on the little finger side, because its main task is to turn the wrists inward (towards the little finger). Additional function: forearm flexion.
5. Pronator quadratus carpi – performs movements similar to the pronator teres. It differs in that it is a quadrangular plate, which is located next to the palm, i.e. from the other side of the forearm.
6. Hand support – rotates the forearm outward (supinates) and is included in the work when the arm is extended at the elbow joint. The supinator is located deeper than the pronator and crosses it crosswise on the other side, i.e. attached from the elbow to the thumb side.
7. Finger flexors and extensors - these muscles are located on the external and on inside forearms. Flexors are usually trained to be strong grip. There is little volume from them, but we will talk about them too.
8. Brachial muscle (brachialis) – We talked about it in the article about. It does not belong to the muscles of the forearms, but in all flexion movements with a pronated hand (“hammer”, “reverse grip barbell curl”, etc.) it does most of the work. These flexion exercises are important to perform because they are the main exercises for developing the brachioradialis muscle (it makes up the bulk of the forearms.

Tip: Train your forearms on your biceps days, otherwise if you do curls on a different day, you risk overloading your forearms.

Tip: Train your forearms AT THE END of your main workout. The forearms are the link in all pulling movements. If you hammer your forearms at the beginning of your workout, you won't be able to properly engage the rest of your muscle groups.

In the near future, friends, an article will be published about detailed training schemes for the forearms. I'm sure many of you will be very interested.

P.S. Subscribe to blog updates. It will only get worse.

With respect and best wishes,!

Among the muscles of the forearm there are not only flexors and extensors, but also, due to the new ability to rotate the radius near the ulna, there are special muscles - pronators and supinators.

Muscles of the forearm (anterior group) (Fig. 189)

The pronator teres (m. pronator teres) begins with two heads: caput humerale - from the medial epicondyle and intermuscular septum of the shoulder; caput ulnare - from the ulnar tuberosity. Between the heads there is an intermuscular gap for the passage of n. medianus. The muscle crosses the forearm diagonally from the medial side and is attached to the lateral edge of the middle part of the radius. The pronator teres borders the ulnar fossa with its medial edge. In front, the muscle belly is covered by the lacertus fibrosus of the biceps brachii.

Innervation: n. medianus (СVI-VII).

Function. Pronates the forearm and participates in flexion of the elbow joint.

The radial flexor carpi (m. flexor carpi radialis) is located slightly lower and closer to the medial edge of the forearm. It starts from the medial epicondyle and the medial intermuscular septum of the shoulder. Crosses diagonally the entire forearm in the direction of the elevation of the first finger. The muscle has a long thin tendon starting from the level of the middle of the forearm. The tendon extends over the wrist joints and attaches to the palmar surface of the base of the metacarpal bone.

Innervation: n. medianus (СVI-VIII).

Function. Participates in flexion of the elbow and wrist joints, and when the wrist joint is extended, it can pronate the forearm. With simultaneous contraction of the long and short extensor carpi radialis, it is possible to abduct the hand to the radial side.

189. Muscles and fascia of the right forearm (according to R. D. Sinelnikov).
1 - f. antebrachii; 2 - m. flexor carpi ulnaris; 3 - m. palmaris longus; 4 - m. flexor carpi radialis; 5 - m. brachioradialis; 6 - m. pronator teres; 7 - m. biceps brachii.

Long palmaris muscle(m. palmaris longus) (Fig. 189) is located medial to the previous one. Starts from the medial epicondyle of the humerus. The thin muscle belly at the level of the middle of the forearm turns into a thin long tendon, which passes into the palm along the surface of the retinaculum flexorum between the muscles of the 1st and 5th fingers. On the palmar surface, the tendon expands to form a thin fibrous plate over the entire surface of the palm, called aponeurosis palmaris.

Innervation: n. medianus (СVI-VIII-ThI).

Function. Produces flexion in the elbow and wrist joints. Stretches the palmar aponeurosis when making a fist.

The flexor carpi ulnaris (m. flexor carpi ulnaris) is the outermost muscle on the medial edge of the forearm. Like the pronator teres, it has two heads: the caput humerale starts from the medial epicondyle, the caput ulnare - from the olecranon process and the posterior surface of the ulna. It is attached to the pisiform bone, from which the tendon continues to the hamate bone in the form of a lig. pisohamatum and lig. pisometacarpeum to the V metacarpal bone.

The attachment of the tendon to the pisiform bone increases the torque of the muscle.

Innervation: n. ulnaris (СVIII-ThV).

Function. Produces flexion in the wrist joint, and brings the hand with other muscles. On elbow joint acts as a flexor only after the joint is bent to 30-40°, because in this case the origin of the muscle is located in front of the frontal axis.

The superficial flexor of the fingers (m. flexor digitorum superficialis) lies under the muscles described above. The muscle begins with two heads: caput humeroulnare - from the medial epicondyle of the shoulder and the coronoid process of the ulna, caput radiale - from the anterior surface of the radius below the attachment of the biceps brachii muscle. At the level of the middle third of the forearm, four tendons begin from the muscle belly, which pass into the canalis carpalis on the hand and end on the middle phalanx from the II to V fingers. At the level of the distal (nail) phalanx, the superficial flexor tendon splits into two legs and covers the deep flexor tendon (Fig. 190). This increases the torque of the flexor digitorum superficialis.

Innervation: n. medianus (СVIII-ThI).

190. Attachment of the flexor and extensor tendons of the fingers (according to R. D. Sinelnikov).
1 - m. extensor digitorum; 2 - m. interosseus; 1.3 - m. lumbricalis I; 4 - chiasma tendineum (m. flexor digitorum superficialis with m. flexor digitorum profundus); 5 - tendo m. flexoris digitorum profundi; 6 - aponeurosis dorsalis; 7 - vagina fibrosa digitorum minus.

Function. Acts on the middle phalanx of the fingers, bending them at the interphalangeal joints. When the fingers are extended, it can act as a flexor in the wrist joint. It also promotes flexion of the elbow joint.

191. Muscles of the right forearm (second layer).
1 - m. flexor digitorum profundus; 2 - m. flexor carpi ulnaris; 3 - m. opponens digiti minimi; 4 - m. adductor pollicis; 5 - m. flexor pollicis brevis; 6 - m. abductor pollicis brevis; 7 - m. pronator quadratus; 8 - m. flexor policis longus; 9 - m. extensor carpi radialis longus; 10 - m. supinator; 11 - m. brachioradialis.

The deep flexor of the fingers (m. flexor digitorum profundus) (Fig. 191) starts from the ulna and interosseous membrane, covered by the superficial flexor of the fingers. Four thin tendons, passing onto the hand through the canalis carpalis, are attached to the base of the distal (nail) phalanges of the II-V fingers.

Innervation: n. medianus, n. ulnaris (СVI-ThI).

Function. Flexes the distal and middle phalanges from the II to V fingers at the interphalangeal joints. When the fingers are extended, it promotes flexion at the wrist joint.

The long flexor of the first finger (m. flexor pollicis longus) starts from the radius below its tuberosity, the long tendon passes to the first finger through the canalis carpalis. Attached to the base of the second phalanx of the first finger.

Innervation: n. medianus (СVI-СVII).

Function. Flexes the interphalangeal joints of the first finger. Promotes flexion at the intercarpal joint.

The quadratic pronator (m. pronator quadratus) is a flat, thin quadrangular muscle plate located on the distal part of the interosseous membrane of the forearm bones.

Innervation: n. medianus (СVI-ThI).

Function. Rotates the radius inward.

In the forearm area there are two muscle groups: anterior and posterior. The flexors and pronators are located in the anterior, and the extensors and supinators are located in the posterior. Muscles of the anterior and rear groups form a superficial and deep layer

The muscles of the forearm are divided into posterior and anterior groups, each of which has a superficial and deep layer.

Front group

Surface layer

Pronator teres (m. pronator teres) pronates the forearm (rotates it forward and inward so that the palm turns posteriorly (downward) and the thumb inward toward the median plane of the body) and participates in its flexion. Fat and short muscle, consisting of two heads. The large, humeral head (caput humerale) begins from the medial epicondyle of the humerus and the medial intermuscular septum of the brachial fascia, and the small, ulnar head (caput ulnare) begins from the coronoid process of the ulnar tuberosity. Both heads, connecting, form a flattened abdomen. The attachment point is the middle third of the radius.

Brachioradialis muscle (m. brachioradialis) flexes the forearm and takes part in both pronation and supination of the forearm (rotates it in such a way that the palm turns anteriorly (upward) and the thumb outward from the median plane of the body) of the radius. The muscle has a fusiform shape, starts from the humerus above the lateral epicondyle and from the lateral intermuscular septum of the brachial fascia, and is attached at the lower end of the body of the radius.

Radial flexor of the hand (m. flexor carpi radialis) bends and partially pronates the hand. A long, flat, bipennate muscle, the proximal part of which is covered by the aponeurosis of the biceps brachii muscle. Its point of origin is located on the medial epicondyle of the humerus and fascia of the forearm, and its attachment point is on the base of the palmar surface of the second metacarpal bone.

Long palmar muscle (m. palmaris longus) stretches the palmar aponeurosis and takes part in flexion of the hand.

A characteristic feature of the muscle structure is a short fusiform abdomen and a long tendon. It begins on the medial epicondyle of the humerus and fascia of the forearm, medially to the flexor carpi radialis, and is attached to the palmar aponeurosis (aponeurosis palmaris).

Flexor carpi ulnaris (m. flexor capiti ulnaris) bends the hand and takes part in its adduction. Characterized by a long abdomen, thick tendon and two heads. The humeral head has its origin at the medial epicondyle of the humerus and the fascia of the forearm, and the ulnar head has the olecranon and the upper two-thirds of the ulna. Both heads are attached to the pisiform bone, some of the bundles are attached to the hamate and V metacarpal bones.

Superficial flexor of the fingers (m. flexor digitorum superficialis) bends the middle phalanges of the II–V fingers. This vastus muscle covers up flexor radialis wrist and palmaris longus muscle and consists of two heads. The humeroulnar head (caput humeroulnare) starts from the medial epicondyle of the humerus and ulna, the radial head (caput radiale) - from the proximal part of the radius. The heads form a single abdomen with four tendons, which pass onto the hand and are each attached by two legs to the base of the middle phalanges of the II–V fingers of the hand.

Deep layer

Flexor pollicis longus (m. flexor pollicis longus) flexes the distal phalanx of the first (thumb) finger. A long, flat, unipennate muscle, its origin is the upper two-thirds of the anterior surface of the radius, the interosseous membrane (membrana interossea) between the radius and ulna, and partly the medial epicondyle of the humerus. Attached at the base of the distal phalanx of the thumb.

Flexor digitorum profundus (m. flexor digitorum profundus) flexes the entire hand and the distal phalanges of the II–V fingers. It is characterized by a highly developed flat and wide abdomen, the origin of which is located on the upper two-thirds of the anterior surface of the ulna and the interosseous membrane. The attachment point is located at the base of the distal phalanges of the II–V fingers.

Square pronator (m. pronator quadratus) rotates the forearm inward (pronates). The muscle is a thin quadrangular plate located in the area of ​​the distal ends of the bones of the forearm. It begins on the medial edge of the body of the ulna and attaches to the lateral edge and anterior surface of the radius.

Back group

Surface layer

Extensor carpi radialis longus (m. extensor carpi radialis longus) flexes the forearm at the elbow joint, extends the hand and takes part in its abduction. The muscle has a spindle-shaped shape and is distinguished by a narrow tendon, significantly longer than the abdomen. Top part The muscle is covered by the brachioradialis muscle. Its point of origin is located on the lateral epicondyle of the humerus and the lateral intermuscular septum of the brachial fascia, and its attachment point is on the dorsal surface of the base of the second metacarpal bone.

Extensor carpi radialis brevis (m. extensor carpi radialis brevis) extends the hand, retracting it slightly. This muscle is slightly covered by the extensor carpi radialis longus, originates from the lateral epicondyle of the humerus and the fascia of the forearm, and is attached to the dorsum of the base of the third metacarpal bone.

Anterior muscle group, superficial layer

Anterior muscle group, deep layer

Posterior muscle group, superficial layer

Posterior muscle group, deep layer