The state of mobility of the foot depends on the functioning of its joints, ligaments and muscles. A certain role in their life is assigned to the muscles of the fingers of each limb. They ensure the correct movement of the bone levers in the ankle joint, and in the event of damage or disease, the functioning of the entire department is disrupted. So, let's look at what the short extensor of the big toe and its opposite, similar muscles of the hand, are, as well as possible actions for their disease.
About the muscles that provide mobility of the limbs
Latin gives this muscle the definition Musculus extensor hallucis brevis. These are the fibers that allow the thumb to function normally.
The short extensor muscle of the thumb begins from the heel bone, and then goes forward and, moving closer to the conditionally midline of the body, passes into the area of the tendon, which is attached to the base of one of the phalanges. This muscle then connects to another called the extensor longus. If there is a violation in this department, it is not only the big toe that becomes difficult to move: a person cannot rise on tiptoe and simply raise his toes up.
However, it is important for a person not just to raise or lower his toes, but also to carry out lateral movements. The extensor digitorum brevis is responsible for this function. We are talking about a flat muscle located directly on the back of the foot. It also starts from the heel bone, and then passes into the tendons, which connect to the fibers of the long extensor muscle and are attached to the bases of the phalanges. The extensor digitorum brevis is also responsible for abducting each of them to the side, and without this the leg would not be able to move normally, and the person would not be able to walk, run or play various sports.
The movement of the hands is also carried out thanks to the action of muscles, and among them the short flexor of the thumb takes its place, without the functioning of which it would be impossible, for example, to grasp the handrails in transport or hold a child’s hand. Starting at the bones of the wrist, this muscle goes in a distant direction and forms two heads: a superficial one, which is attached to the external sesamoid bone, and a deep one, connected to both sesamoid bones. The flexor pollicis brevis in its normal state ensures the functioning of the proximal phalanx and is partly responsible for the abduction of the first finger. Moreover, both this muscle and all the links with which it is connected must be healthy so that a person can carry out active movements of the hand. 
The motor function of this area occurs with the participation of other muscles. So, on the side of the eminence there is a short muscle that abducts the thumb. It starts from the tendon of long fibers involved in its abduction, and in the normal state this muscle is attached to the lateral surface of the base of the largest phalanx, and in the thickness of its tendon there is a sesamoid bone that provides tendon protection. However, when the bone is damaged as a result of injury or other disease, the tendon also suffers. Interacting with other links, the abductor pollicis brevis muscle slightly opposes it when performing its function, and also participates in flexion of the proximal phalanx.
However, these muscles, designed for flexion, will not be toned without their opposites, so it is natural that the extensor pollicis brevis is needed. This is one of the muscles of the forearm, located in the lower part of the section. It begins at the radius, passes down and ends at the tendon of the long muscle, attaching to the dorsal surface of the largest phalanx, and its condition, the ability to interact with other links, ensures the coherence of the movement of the hand. During movement, they all interact, and a problem in one area immediately entails a change in the state of another.
Common disease and possible treatment
We are talking about a disease such as synovitis, which affects the joints of the limbs, affecting the muscles, and for this reason the functioning of the foot or hand is disrupted, but most often the lower limbs are affected. When a joint is injured or pathogenic microorganisms enter the cavity, inflammation of the synovial membrane or synovitis occurs. 
It affects the extensor muscles and nearby tendons, and as a result characteristic symptoms appear:
- difficulty moving;
- pain;
- edema;
- joint instability.
Synovitis can also be recognized by the presence of such signs as lameness, lack of heel-to-toe roll, and the stride becomes shortened. Pain, swelling, restriction and even blocking of the joint, a local increase in temperature during an exacerbation of the disease are observed with inflammation in the hand area.
Treatment depends on how affected the synovial membrane is. As practice shows, at the initial stage, synovitis can quickly disappear if you reduce physical activity. Treatment begins with fixation of the joint, and then therapy is prescribed using non-steroidal anti-inflammatory drugs. If synovitis is observed in a simple form, the doctor may prescribe Contrical or Trasylol in the form of injections, and also recommend including traditional medicine procedures in the treatment. At the initial stage of the disease, baths using chamomile, sage, nettle leaves or oak bark help to reduce synovitis, and to carry out a home procedure, you first need to pour 1 tablespoon of raw materials into 1 liter of water and boil, and then cool to a comfortable temperature.
If synovitis has acquired a more complex form, the use of corticosteroids in various dosage forms is practiced. Thus, treatment may include the use of Prednisolone, Hydrocortisone or Diprospan in injections, Prednisolone, Celeston or Triamcinolone in tablets, as well as one of the topical drugs, and this could be Hydrocortisone ointment, Afloderm cream or Lorinden lotion. 
The use of magnetic therapy is also practiced, but if the patient has poor blood clotting and is prone to sudden bleeding, this is contraindicated. The doctor can prescribe laser treatment or electrophoresis for up to 15 procedures, each lasting 20 minutes. In cases where conservative methods do not give the desired result, surgical intervention is used.
The goal of the set of measures is to restore functions lost as a result of the disease. However, it should be taken into account that if the cause of the disease was injury and tendon rupture, then even with proper treatment, the functions of the finger may be limited due to the formation of scar tissue at the site of injury. Thus, treatment and its effectiveness depend on the severity of the disease, and in advanced cases, consequences such as loss of the ability to move and even death in the infectious form of the disease are possible. To prevent damage to joints, muscles and tendons, it is recommended to avoid excessive exercise and include foods with a high content of gelatin, vitamin C, and phytoncides in your diet.
2016-08-19
Why do the joints of the thumbs hurt and how to deal with it?
The thumb on the hand is considered the main one. He opposes the rest of the fingers. The counting starts from there. The finger is important in work activity and significant in sign language. People consider it an indicator of behavior, character, strength, and health.
Peculiarities
The thumb has a unique anatomical structure and structure. Perhaps these features can explain the frequent pain in the thumb joint. The table shows comparative characteristics of the bones, joints and muscles of the thumb and other fingers.
| Thumb | Other fingers |
| Number of phalanges: 2 – proximal and distal. | Number of phalanges: 3 – proximal, middle, distal. |
| The carpometacarpal joint has a saddle shape. Abducts and adducts the finger along with the metacarpal bone. | The carpometacarpal joints are inactive and form a solid foundation. |
| The muscle group consists of 4 short muscles - flexor, abductor, adductor, opponens pollicis. | The little finger has 3 muscle groups. The middle fingers have 4 lumbrical muscles for flexing the phalanges, as well as palmar and dorsal interosseous muscles. |
The hand has its own muscular system. Thanks to this, the mobility of the thumb increases. He acquires the ability to perform a variety of movements, but at the same time experiences a large load during work.
Etiology
The causes of thumb disease are as follows:
- heredity;
- Lifestyle;
- degenerative changes in joints;
- Infectious-allergic polyarthritis - a nonspecific inflammatory reaction of the joint to various infections;
- bursitis - inflammation of the synovial fluid;
- rhiziarthrosis or arthrosis of the thumb, accompanied by damage to cartilaginous tissue with bone growths;
- de Quervain's tenosynovitis - the result of professional or household overload of the hand;
- gout is a metabolic disease characterized by the deposition of urates (uric acid salts) in tissues, clinically manifested by arthritis;
- bruises, injuries.
As can be seen from the list, the etiology of the disease is diverse. It can be either local or general. In some cases, only the thumb should be treated. In others, there is a specific disease that contributes to the development of the disease.
Clinical picture
Regardless of the cause, the clinical manifestations of thumb disease are approximately the same. In an acute process, external signs of joint damage appear most clearly. When trying to move, a sharp pain occurs and his mobility is limited. Swelling and hyperemia occur. Severe forms of damage in combination with diseases of other joints are accompanied by hyperthermia, changes in the blood picture with an increase in the number of leukocytes, and an increase in ESR.
Infectious polyarthritis affects the small joints of the hands. The disease occurs mainly after an infection, most often streptococcal. The course is favorable, the disease is reversible, there is no joint deformation.
Rheumatoid arthritis is a progressive chronic disease with the formation of antibodies, to which the body responds by producing rheumatoid factor (autoantibodies). The disease creeps up gradually. Occurs with damage to symmetrical fingers. As it progresses, joint deformation with subluxation occurs.
Gout is associated with impaired purine metabolism and an increase in urate levels in the blood. Characterized by acute pain at the slightest movement, redness, swelling of the joints. The lesion occurs in the form of monoarthritis of the phalanx. After the formation of small nodules - tophi - in the tissues, the joints hurt almost constantly.
Rhizarthrosis is a degenerative lesion of cartilage tissue. It can appear at a young age, but is more common in older people. The cartilage gradually thins out. Bone growths appear, and the surrounding tissues become inflamed. The joints come closer together and rub against each other, which is why pain occurs with arthrosis.
Bursitis can be serous, purulent and hemorrhagic. Depending on the severity of the disease, characteristic symptoms develop - pain, joints swell due to the accumulation of effusion, and do not move. The skin over the joints may become red.
Bruises are the consequences of falls or blows. This part of the hand is the most vulnerable. The thumb is located separately, so it is more often injured. In addition to pain and swelling, bruising often occurs with an injury.
It is difficult for an ignorant person to understand the cause of the disease. You should not engage in independent treatment without making an accurate diagnosis, as this contradicts the principle of “do no harm.”
Therapy
The diagnosis is decisive for treatment. In the acute period, many symptoms are similar, and differentiation is very difficult. Initial treatment measures are aimed at:
- relieving inflammation and swelling;
- relief of acute pain;
- joint immobilization;
- restoration of thumb mobility.
To clarify the diagnosis and select specific treatment, testing, instrumental studies (x-ray in 2 projections, less often ultrasound, MRI) are carried out, blood and urine tests are taken. Once the cause of the disease has been established, conservative or surgical treatment is prescribed. The principles of therapy are as follows.
For severe pain in the thumb, non-steroidal drugs in the form of ointments and gels have a good effect: ibuprofen, ketanol, ortofen, indomethacin, voltaren, etc. Corticosteroid hormonal drugs are used. The joint is provided with complete rest. Any load on the hand is eliminated. When the acute process subsides, physiotherapy procedures are used - UHF, electrophoresis, paraffin treatment.
For degenerative joint diseases, it is necessary to restore cartilage tissue using chondroprotectors, hyaluronic acid, and vitamins.
If your joints hurt, you should pay attention to your lifestyle. For example, gout is the result of constant overeating, alcohol abuse, and uncontrolled use of certain medications. In addition to non-steroidal drugs to reduce uric acid to normal, fasting and drinking plenty of alkalizing drinks are recommended.
De Quervain's tenosynovitis occurs with constant excessive load on the joints of the thumbs in everyday life, as well as in people of such professions as sculptor, seamstress, wood or metal carver, loader, knitter, musician, etc. To exclude the disease, you should reduce to a minimum grasping, twisting, flexion movements of the thumb.
Abductor pollicis longus muscle, m. abductor pollicis longus, has a flattened bipinnate abdomen, turning into a thin long tendon. The muscle lies in the distal half of the dorsolateral surface of the forearm. Its initial part is covered by m. extensor carpi radialis brevis and m. extensor digitorum, and the lower one is located under the fascia of the forearm and skin.
The muscle originates from the posterior surface of the radius and ulna and from the interosseous membrane of the forearm, moving obliquely downwards, bends around the radius with its tendon and, passing under the extensor retinaculum, attaches to the base of the first metacarpal bone.
Function: abducts the thumb, taking part in the abduction of the entire hand.
Innervation: n. radialis.
Blood supply: a. interossea posterior, a. radialis.
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a. interossea posterior, a. radialis
n. radialis (C VI -C VIII)
abducts the thumb
Abductor pollicis longus muscle(lat. Musculus abductor pollicis longus ) - muscle of the forearm of the posterior group.
The muscle has a flattened bipinnate belly, which turns into a thin long tendon. It lies in the distal half of the dorsolateral surface of the forearm. The initial part of the muscle is covered by the short extensor carpi radialis and the extensor digitorum, and the lower part is located under the fascia of the forearm and skin.
The muscle starts from the posterior surface of the radius and ulna and from the interosseous septum of the forearm, moving obliquely downwards, bends around the radius with its tendon and, passing under the extensor retinaculum, attaches to the base of the first metacarpal bone.
Function
Abducts the thumb and hand.
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An excerpt characterizing the abductor pollicis longus muscle
Princess Marya, lowering her head, left the circle and went into the house. Having repeated the order to Drona that there should be horses for departure tomorrow, she went to her room and was left alone with her thoughts.For a long time that night, Princess Marya sat at the open window in her room, listening to the sounds of men talking coming from the village, but she did not think about them. She felt that no matter how much she thought about them, she could not understand them. She kept thinking about one thing - about her grief, which now, after the break caused by worries about the present, had already become past for her. She could now remember, she could cry and she could pray. As the sun set, the wind died down. The night was quiet and fresh. At twelve o'clock the voices began to fade, the rooster crowed, the full moon began to emerge from behind the linden trees, a fresh, white mist of dew rose, and silence reigned over the village and over the house.
One after another, pictures of the close past appeared to her - illness and her father’s last minutes. And with sad joy she now dwelled on these images, driving away from herself with horror only one last image of his death, which - she felt - she was unable to contemplate even in her imagination at this quiet and mysterious hour of the night. And these pictures appeared to her with such clarity and with such detail that they seemed to her now like reality, now the past, now the future.
Then she vividly imagined that moment when he had a stroke and was dragged out of the garden in the Bald Mountains by the arms and he muttered something with an impotent tongue, twitched his gray eyebrows and looked at her restlessly and timidly.
“Even then he wanted to tell me what he told me on the day of his death,” she thought. “He always meant what he told me.” And so she remembered in all its details that night in Bald Mountains on the eve of the blow that happened to him, when Princess Marya, sensing trouble, remained with him against his will. She did not sleep and at night she tiptoed downstairs and, going up to the door to the flower shop where her father spent the night that night, listened to his voice. He said something to Tikhon in an exhausted, tired voice. He obviously wanted to talk. “And why didn’t he call me? Why didn’t he allow me to be here in Tikhon’s place? - Princess Marya thought then and now. “He will never tell anyone now everything that was in his soul.” This moment will never return for him and for me, when he would say everything he wanted to say, and I, and not Tikhon, would listen and understand him. Why didn’t I enter the room then? - she thought. “Maybe he would have told me then what he said on the day of his death.” Even then, in a conversation with Tikhon, he asked about me twice. He wanted to see me, but I stood here, outside the door. He was sad, it was hard to talk to Tikhon, who did not understand him. I remember how he spoke to him about Lisa, as if she were alive - he forgot that she died, and Tikhon reminded him that she was no longer there, and he shouted: “Fool.” It was hard for him. I heard from behind the door how he lay down on the bed, groaning, and shouted loudly: “My God! Why didn’t I get up then?” What would he do to me? What would I have to lose? And maybe then he would have been consoled, he would have said this word to me.” And Princess Marya said out loud the kind word that he said to her on the day of his death. “Darling! – Princess Marya repeated this word and began to sob with soul-easing tears. She now saw his face in front of her. And not the face that she had known since she could remember, and which she had always seen from afar; and that face is timid and weak, which on the last day, bending down to his mouth to hear what he said, she examined up close for the first time with all its wrinkles and details.
Abductor pollicis brevis muscle(m.abductor pollicis brevis), flat, located superficially. It begins with muscle bundles on the lateral part of the flexor retinaculum, the tubercle of the scaphoid bone and the trapezium bone. Attaches to the radial side of the proximal phalanx of the thumb and to the lateral edge of the extensor pollicis longus tendon.
Function: abducts the thumb.
Innervation: median nerve (C V -Th I).
Blood supply: superficial palmar branch of the radial artery.
Muscle that opposes the thumb to the hand(m.opponens pollicis), partially covered by the previous muscle, fused with the short flexor pollicis muscle, located medial to it. It begins on the flexor retinaculum and on the trapezius bone. Attaches to the radial edge and the anterior surface of the first metacarpal bone.
Function: contrasts the thumb with the little finger and all other fingers of the hand.
Innervation: median nerve (C V -Th I).
Blood supply:
Flexor pollicis brevis(m.fleixor pollicis brevis) is partially covered by the short abductor pollicis muscle. Surface head(caput superficiale) begins on the flexor retinaculum, deep head(caput profundum) - on the trapezium and trapezoid bones, on the second metacarpal bone. It is attached to the proximal phalanx of the thumb (there is a sesamoid bone in the thickness of the tendon).
Function: flexes the proximal phalanx of the thumb and the finger as a whole; participates in the adduction of this finger.
Innervation: median nerve (C V - Th I), ulnar nerve (C VIII - Th I).
Blood supply: superficial palmar branch of the radial artery, deep palmar arch.
Adductor pollicis muscle(m.abductor pollicis), located under the tendons of the long flexor fingers (superficial and deep) and under the lumbrical muscles. It has two heads - oblique and transverse. The oblique head (caput breve) begins on the capitate bone and the base of the II and III metacarpal bones.
Cross head(caput transversum) begins on the palmar surface of the third metacarpal bone. The muscle is attached by a common tendon, which contains a sesamoid bone, to the proximal phalanx of the thumb.
Function: brings the thumb to the index finger, participates in flexion of the thumb.
Innervation:
Blood supply:
Muscles of the eminence of the little finger
Palmaris brevis(m.palmaris brevis) is a rudimentary cutaneous muscle, represented by weakly expressed muscle bundles in the subcutaneous base of the eminence of the little finger. The bundles of this muscle begin on the flexor retinaculum and are attached to the skin of the medial edge of the hand.
Function: faint folds form on the skin of the eminence of the little finger.
Innervation: ulnar nerve (C VIII -Th I).
Blood supply: ulnar artery.
Abductor digiti minimi muscle(m.abductor digiti minimi), located superficially. It begins on the pisiform bone and the tendon of the flexor carpi ulnaris. Attaches to the medial side of the proximal phalanx of the little finger.
Function: withdraws his little finger.
Innervation: ulnar nerve (C VIII -Th I).
Blood supply: deep branch of the ulnar artery.
Opponus little finger muscle(m.opponens digiti minimi), begins with tendon bundles on the flexor retinaculum and the hook of the hamate. Located under the muscle that abducts the little finger. Attached to the medial edge and anterior surface of the fifth metacarpal bone.
Function: contrasts the little finger with the thumb.
Innervation: ulnar nerve (C VIII -Th I).
Blood supply:
Flexor digiti brevis(m.flexor digiti minimi brevis) begins with tendon bundles on the flexor retinaculum and the hook of the hamate. Attaches to the proximal phalanx of the little finger.
Function: bends the little finger.
Innervation: ulnar nerve (C VIII -Th I).
Blood supply: deep palmar branch of the ulnar artery.
Middle hand muscle group
Vermiform muscles(mm.lumbricales) thin, cylindrical in shape, 4 in number, lie directly under the palmar aponeurosis. They begin on the deep digital flexor tendons. The first and second lumbrical muscles begin on the radial edge of the tendons leading to the index and middle fingers. The third muscle begins on the edges of the tendon facing each other, going to the third and fourth fingers, the fourth - on the edges of the tendons facing each other, going to the fourth finger and little finger. Distally, each lumbrical muscle is directed to the radial side of the II-V fingers, respectively, and passes to the rear of the proximal phalanx. The vermiform muscles are attached to the base of the proximal phalanges along with the tendon extensions of the extensor digitorum.
Function: bend the proximal phalanges and extend the middle and distal phalanges of the II-IV fingers.
Innervation: the first and second lumbrical muscles - the median nerve; the third and fourth are the ulnar nerve (C V -Th I).
Blood supply: superficial and deep palmar arches.
Interosseous muscles(mm.interassei) are located between the metacarpal bones and are divided into two groups - palmar and dorsal (Fig. 169).
Palmar interosseous muscles(mm.interassei palmares) in number three are located in the second, third and fourth interosseous spaces. They begin on the lateral surfaces of the I, IV and V metacarpal bones. They are attached by thin tendons to the back of the proximal phalanges of the II, IV and V fingers.
First palmar interosseous muscle begins on the ulnar side of the second metacarpal bone; attaches to the base of the proximal phalanx of the second finger. Second and third palmar interosseous muscles begin on the radial side of the IV-V metacarpal bone; attached to the dorsum of the proximal phalanges of the fourth and fifth fingers.
Function: bring the II, IV and V fingers to the middle (III) finger.
Innervation: ulnar nerve (C VII -Th I).
Blood supply: deep palmar arch.
Dorsal interosseous muscles(mm. interossei dorsales) are much thicker than the palmar ones, there are 4 of them. All 4 muscles occupy the spaces between the metacarpal bones. Each muscle begins with two heads on the surfaces of the I-V metacarpal bone facing each other. The muscles are attached to the base of the proximal phalanges of the II-V fingers.
The tendon of the first dorsal interosseous muscle is attached to the radial side of the proximal phalanx of the index finger, the second muscle - to the radial side of the proximal phalanx of the middle (III) finger. The third muscle attaches to the ulnar side of the proximal phalanx of this finger; The tendon of the fourth dorsal interosseous muscle is attached to the ulnar side of the proximal phalanx of the fourth finger.
Function: fingers I, II and IV are moved away from the middle finger (III).
Innervation: ulnar nerve (C VII -Th I).
Blood supply: deep palmar arch, dorsal metacarpal arteries.
