Forearm dislocation - epicondylitis and instability

Anatomy of the forearm.

The forearm consists of two bones - the ulna and the radius.
If you stretch your arms forward with your palms up, the ulna will be on the little finger side, and the radius will be on the thumb side. The ulna widens at the elbow, and the radius widens towards the wrist. The main movement performed by the forearm is rotation. In this case, the ulna is rigidly fixed in a block with the humerus, and the radius rotates around it. This movement occurs, for example, when screwing in a light bulb or opening a door with a key.

In some cases, significant displacement of the fragments occurs, as a result of which they perforate the skin. This type of fracture is called open, and it requires immediate surgical intervention, as it is characterized by a high risk of infectious complications.

Muscular system

The forearm directly affects the strength of the fist and the grip of small objects with the hand . The muscles responsible for flexion and extension of the upper limb . They are divided into two main layers:

• superficial (starts from the medial epicondyle);
• deep (attached to the lateral process, interosseous membrane).

Pronators and supinators , which consist of many very fine fibers and are penetrated by tendons, pass along the radius . Gradually they move to the wrist area, branching along the palm to the fingers, responsible for fine motor skills and contraction when gripping.

Front group

The group includes several large and small muscles located on the outside of the human arm:

• pronator teres, responsible for wrist flexion;
• long palmar;
• flexor ulnaris;
• superficial, controlling the flexion of the fingers.

All long muscles cross on the palm and bifurcate at the phalanges. They are fixed at the level of the middle of the finger.

Back group

Includes muscles that run along the outside of the arm. Contains the largest flexors of the forearm , responsible for the work of all fingers:

• deep;
• long;
• square.

The posterior group can be easily felt during palpation. It protects blood vessels and the radial nerve from damage, taking the brunt of injury.

Symptoms of a forearm fracture in the middle third.

Symptoms of a forearm fracture in the middle third are standard for any fracture - pain, swelling, bruising, bone crepitus, deformity, impaired hand function.

With open injuries, a violation of the integrity of the skin also occurs. With very severe soft tissue damage, the fracture can be complicated by the occurrence of compartment syndrome, in which high interstitial pressure leads to irreversible damage to muscle tissue. In any case, if you have the above symptoms, you should immediately consult a traumatologist.

Forearm: where is it located? Photo of a human skeleton

So, a little theory. An anatomical atlas or a skeleton model will help answer the question of where the human forearm is located. The bones of the forearm are one of the components of the human upper limb, which plays an important role in the mobility of the arms. By carefully studying the skeleton image, it is easy to see where the shoulder and forearm are located.

From the name you can guess that the forearm is located under the humerus bones, precedes it and together forms the basis of the upper limb of a person. To understand the anatomy of the upper limb, it is necessary to study the bones that make it up.

Treatment of fractures of the middle third of the forearm.

Fractures of both forearm bones in the middle third in adults should almost always be treated surgically. In a cast it is impossible to adequately compare bone fragments in a fracture of the forearm in the middle third, and even if it is possible, secondary displacement always occurs. This subsequently leads to dysfunction of the limb. Plaster immobilization is almost always used as a temporary measure to prevent secondary displacement, perforation of the skin with bone fragments, damage to the neurovascular bundles, and reduce pain. Surgical treatment is currently most often represented by open reduction and osteosynthesis with plates. In some cases, closed osteosynthesis with locking pins, wires, or flexible rods can be used, and in open fractures, it is preferable to apply an external fixation device. In children, this group of fractures can be treated conservatively if adequate reduction can be achieved in a plaster cast.

Below is a clinical example of the treatment of a patient with a forearm fracture.

Patient X. Trauma at home, fell on a curb, received a closed fracture of both bones of the right forearm with displacement, rupture of the distal radio-ulnar joint. I contacted the RTP and x-rays were taken. A plaster cast was applied.

The patient contacted K+31; given the nature of the fracture, the patient was offered surgical intervention.

Intraoperative assessment of the stability of the distal radioulnar joint.

Osteosynthesis of both bones of the right forearm was performed with 3.5 mm metaphyseal plates, and the distal radioulnar joint was fixed with a screw.

Appearance of the limb after surgery, angular deformity eliminated. The limb segment is stable, movements in the elbow and wrist joints are not limited, rotation of the forearm is limited due to the presence of a positioning screw, which will be removed after 6 weeks.

X-rays after surgery.

This osteosynthesis is very stable and allows you to begin rehabilitation within a day after surgery. Forced loads on the forearm are naturally limited until x-ray confirmation of consolidation. It is advisable to perform X-ray control after 6 and 12 weeks. If signs of fusion are well expressed, full weight bearing is possible 12 weeks after surgery.

Fractures of the upper (proximal) part of the humerus

The humerus is the bone that is located between the elbow and the shoulder girdle. Usually the shoulder is the part of the body that is located between the neck and the shoulder joint, but this is incorrect: the shoulder is located lower.

The humerus, like all tubular bones, consists of three parts: upper (proximal), middle (diaphysis) and lower (distal).

The upper (proximal) part of the humerus has a rather complex anatomy and, together with the scapula, forms the shoulder joint. In the proximal part of the humerus, a hemispherical head is distinguished, due to which movements in the shoulder joint are possible. The head is covered with cartilage. Below the head there is a narrowing - the anatomical neck. Under the anatomical neck there are two tubercles - large and small, to which the muscles are attached. The teres minor, infraspinatus, and supraspinatus muscles are attached to the greater tubercle (they rotate the shoulder outward and hold it in the joint). The subscapularis muscle is attached to the lesser tubercle (rotates the shoulder inward). All these muscles form the so-called rotator cuff. Between the tubercles there is a groove in which the tendon of the long head of the biceps brachii passes. Under the tubercles there is another narrowing, which is called the surgical neck. You can read more about the anatomy of the humerus and shoulder joint on our website.

A fracture of the humerus can occur in any of its parts: proximal, middle (shaft) and distal. As a rule, the fracture is localized in one part, but sometimes the fracture line passes through two (for example, the fracture affects the proximal and middle parts of the bone). Each option has its own characteristics, so we will describe them in separate articles.

When does a fracture occur?

Most often, a fracture of the proximal humerus occurs in older people who have osteoporosis, i.e. the bone has little strength. However, a fracture of the proximal humerus can also occur in young people.

A typical injury that causes a fracture is a fall on the arm, but a fracture can also occur from a direct blow to the top of the shoulder. In addition, there are so-called avulsion fractures and fracture-dislocations, which you can read about in a separate article on our website.

Symptoms

Immediately after the fracture, the victim feels pain in the shoulder joint, movements become sharply painful, but more often, shoulder movements are completely impossible. The shoulder may become deformed.

Loss of sensation in the hand, forearm, or shoulder may occur. Numbness or a feeling of pins and needles can be caused both by damage to the nerves during a fracture, and as a result of swelling, which almost always occurs during a fracture.

A few hours after the injury, swelling occurs; later, about a day later, a bruise appears in the area of ​​the shoulder joint (it is mistakenly called a hematoma, but in fact it is just a bruise - the subcutaneous fat is saturated with blood). Over the course of several days or even weeks, this bruise may increase in size and “slide” down, even to the hand.

First aid:

First, make sure the victim is completely safe.

If the patient is unable to walk, call an ambulance. In other cases, you can get to the doctor yourself by taxi - which can be much faster.

Do not try to move your injured arm. This can cause damage to blood vessels, nerves and soft tissue.

If bone fragments protrude from the wound (open fracture), do not try to set them back.

If there is an open fracture, apply a sterile bandage (stop any car that should have sterile bandages in its first aid kit).

Do not apply a tourniquet! Simply bandage the wound tightly and place your hand above the level of the victim's heart.

If it is difficult to apply a bandage, simply cover the wound with sterile wipes or a bandage until the ambulance arrives.

If medical help is not available and the patient must be moved, immobilize (immobilize) the injured limb using temporary splints or a brace.

Temporary splinting can be done using planks, branches, cardboard or rolled up magazines. Avoid applying excessive pressure to your hand.

Suspend your arm from a scarf. A scarf is a piece of fabric with tied ends, worn around the neck and supporting the injured arm.

Headband

What types of fractures are there?

There are several typical types of fractures:

Avulsion of the greater tubercle, fracture of the anatomical neck, fracture of the surgical neck, avulsion of the lesser tubercle, intra-articular fracture (splitting of the head), fracture dislocation.

Each of these typical options can be combined with the other, so that a particular patient may have a combination of, for example, avulsion of the greater tuberosity and a fracture of the surgical neck, or any other option. In addition, the fracture can be impacted - if one fragment is pressed into another. To describe the variety of possible fracture options, traumatologists most often use the Neer classification, which distinguishes one-, two-, three- and four-fragment fractures.

As we have already mentioned, muscles that have different directions are attached to the tubercles. Because of this, bone fragments often shift in the direction where the corresponding muscles pull them.

Typical displacements of tripartite (three-part) fractures. On the left - avulsion of the lesser tubercle and a fracture of the surgical neck, on the right - avulsion of the greater tubercle with a fracture of the surgical neck. The greater tubercle migrates upward and backward.

A large tubercle displaced upward and posteriorly will interfere with abduction, since in this case it will simply collide with the acromial process of the scapula, limiting movement.

A completely severed greater tubercle may move into the subacromial space, and in this case, it will also be impossible to move the arm to the side in the future.

The greater tubercle displaced into the subacromial space (marked with a red arrow)

In general, there are a lot of options for fractures of the proximal part of the humerus; you can read more about them on our website.

Diagnosis

The diagnosis of a fracture of the proximal humerus is made based on the results of examination and additional research methods (x-ray, computed tomography). During the examination, the doctor will ask you about the circumstances of the injury. Try to be as detailed as possible, but at the same time succinctly tell about what happened. Be sure to report the symptoms described above if you have them (numbness, etc.).

The exact nature of the fracture cannot always be determined from radiographs, since there are many types of fractures, and on simple radiographs the fragments are often layered on top of each other. However, an anteroposterior radiograph is always taken first. If the fracture is simple, then this is enough, but if the fracture is complex, then it is necessary to perform either radiography in additional projections (oblique, axial, etc.) or computed tomography. Radiographs in additional projections are technically complex and often require that the hand be given a special position, and this is often impossible due to severe pain. Therefore, surgeons often prefer computed tomography.

In any case, performing a CT scan before conventional radiographs is not always advisable. Magnetic resonance imaging is less informative than computed tomography in diagnosing the nature of the fracture, but sometimes, if the doctor suspects damage to the ligaments or tendons, this study is also performed.

How to treat fractures of the proximal humerus?

There are two main ways to treat fractures - conservative (without surgery) and surgical. The choice of treatment method is made taking into account the nature of the fracture, displacement of bone fragments, the patient’s lifestyle, and concomitant diseases.

All fractures of the proximal humerus can be divided into two types:

- those that can be successfully treated conservatively, i.e. without surgery and

- those that are better to operate on.

Non-surgical treatment is advisable for simple fractures without displacement or with minimal displacement of fragments (less than 1 centimeter). In addition, conservative treatment is indicated in cases where, for various reasons, the patient’s arm did not function before the injury (after a stroke, for example).

The hand is immobilized using special splints made of plaster or modern hardening materials. There are also modern orthoses that are much more comfortable than a conventional plaster splint. The specific type of orthosis or cast that is appropriate is determined by the nature of the fracture. The timing of immobilization is also determined by the nature of the fracture. Usually, with conservative treatment there is more long-term immobilization than with surgical treatment.

In other cases surgical treatment , which allows you to eliminate the displacement, fix the fragments and begin movement in the shoulder joint earlier.

The type of fixation of fragments is determined by the nature of the fracture. When the greater tubercle is torn off, it is often fixed with wire or a screw and wire.

Fixation of the greater tubercle with wire.

For more complex fractures, fixation is performed with an intramedullary pin or plate.

Fixation of the fracture with the PHILOS plate from Synthes.

The requirements for plates for fixation of proximal humerus fractures are very high. They must be made of high-quality alloys, have a large margin of mechanical strength, the screws must be locked in the holes of the plate, and the plate itself must have additional holes for suturing the rotator cuff tendons and ligaments of the shoulder joint. All these features determine their high cost, which in our country can easily exceed 1000 US dollars.

On the left - osteosynthesis with screws, on the right - osteosynthesis with an Arthrex plate with holes for suturing the tendons of the rotator cuff

Osteosynthesis with an intramedullary pin is usually a less traumatic operation, but it has its limitations. As a rule, the choice in favor of an intramedullary pin occurs in simpler fractures without avulsion of the tubercles, or in cases where the fracture line extends to the diaphysis. However, intramedullary osteosynthesis is also possible for more complex fractures, but technically this operation is very difficult.

In elderly patients, one of the main difficulties associated with proximal humerus fractures is osteoporosis. The bone is soft, “sugar”, and ordinary screws in such bone easily cut through and the entire structure becomes unstable.

In addition, in elderly patients, comminuted fractures often do not heal at all, even with ideal reduction (comparison of fragments) and fixation, due to the fact that the blood supply to the head decreases with age. Therefore, if the doctor evaluates the blood supply to the head in an elderly patient as insufficient, then it is not osteosynthesis that is performed, but endoprosthetics - i.e. the joint is replaced with a new artificial one.

Shoulder endoprostheses from Zimmer® (Anatomical Shoulder™, inverse and reverse)

Complications

In addition to the fact that the operation eliminates the displacement of bone fragments, it also has disadvantages. In particular, the main complications of surgical treatment are:

Osteolysis (resorption) of the head. This complication is caused by insufficient blood supply to the head of the humerus, which, being deprived of nutrition, gradually dissolves. Typically, this complication occurs when osteosynthesis is performed instead of the recommended primary arthroplasty. However, this choice is not without meaning, since osteosynthesis is an attempt to “save” the joint. In any case, the risk of osteolysis must be assessed individually for each patient and surgery should be planned based on this assessment. This complication can occur both after surgery and after conservative treatment.

Head perforation with screws. If screws that are too long are used during osteosynthesis, they will perforate the articular surface of the head and interfere with movements in the joint. This is a technical error and can only be avoided by carefully following the rules for performing the operation. In particular, the operating room must be equipped with an electron-optical converter (EOC), which allows the surgeon to take radiographs in several projections and ensure the correct position of the screws.

Impingement syndrome. This is impingement syndrome, where a mechanical obstruction interferes with movement in a joint. Most often, impingement syndrome of the shoulder joint is caused by a collision of a displaced greater tubercle or the upper edge of an incorrectly positioned plate on the acromion process of the scapula.

Frozen shoulder. Sometimes this complication is also called adhesive capsulitis, although these concepts are not entirely synonymous. This complication can occur both after surgery and after conservative treatment. The complication is manifested by a sharp limitation of movements.

Infectious complications – osteomyelitis. To prevent this complication, it is necessary to comply with the requirements of asepsis, and the patient should receive antibiotics for prophylactic purposes (prescribed intravenously 30 minutes before surgery). The incidence of this complication is less than 1%

Rehabilitation

In the postoperative period, the arm is usually immobilized with an abduction orthosis or a plaster cast, and painkillers such as paracetamol or aspirin or ibuprofen may be prescribed.

After normal fusion of the fragments, the function of the shoulder joint is gradually restored, but the significant severity of the injury itself sometimes does not allow the function of the joint to be restored completely.

With stable bracing, exercises to increase range of motion and strengthen muscles can be started as soon as pain subsides. Control examinations by a doctor and control radiographs are required, the frequency of which is determined by the attending physician. During these examinations, the doctor makes recommendations on expanding the rehabilitation program or, conversely, advises stopping the exercises.

You can see sample exercises for rehabilitation on our website (click to go).

What questions should you discuss with your doctor?

1. What are my individual risks of complications during surgical and conservative treatment? Which treatment method will allow me to count on maximum success in my case?
2. How will this injury affect the function of the hand in the future?
3. Can any of my individual factors affect the outcome of treatment (concomitant diseases such as diabetes, etc., bad habits)?
4. Which implant for osteosynthesis is optimal for this type of fracture?
5. How fully can I take care of myself after the operation?
6. When can I return to work if my job involves...?
7. When should follow-up examinations and x-ray examinations be carried out?

Possible complications after osteosynthesis of the middle third of the forearm.

Infection. There are certain risks of infectious complications with any surgical intervention, forearm osteosynthesis is no exception.

Damage to nerves and blood vessels. There is a small risk of damage to the nerves and blood vessels at the level of the forearm during surgery. If after surgery there is weakness and numbness in the hand area, or persistent limitation of movements appears, this is a reason to consult a doctor, since such neuropathy may not resolve without emergency intervention.

Synostosis. In some cases, after a fracture of both bones of the forearm, a bone bridge may arise between them, which will limit the rotational movements of the forearm.

Nonunion. The operation does not guarantee healing of the fracture. Sometimes the bone does not heal, and in such cases a repeat, more complex operation is required.

Smoking and drinking alcohol slow down the healing process and may lead to delayed fracture consolidation.

The structure of the ulna

We have already found out that the forearm is where two long tubular bones are located, connected on both sides with joints. The third side of the ulna is called the medial side and is turned inward, like its edges.

The ulna is located on the outer part of the arm, which is called the medial position. For example, if we consider the limb from the left and right sides, then the left forearm contains the ulna on the left, and the right one on the right. In other words, the ulna is located in the forearm on the little finger side.

The upper epiphysis of the ulna is thicker than the proximal epiphysis of the radius and is articulated with it using a trochlear notch, which is limited by two processes: the coronoid and the ulna. On the inner side of the coronoid process there is a radial notch intended for the head of the radius. The joint, together with the articular surface and cartilage, forms the elbow joint, which allows flexion and extension of the forearm.

The lower epiphysis, on the contrary, is thinner than the distal epiphysis of the radius and is connected to it using an articular circle, and then passes into the wrist joint.

Rehabilitation after osteosynthesis surgery of the middle third of the forearm.

After osteosynthesis surgery, it will take a short period of time for swelling and pain to subside before you begin active rehabilitation. In the early postoperative period, it is possible to use a scarf bandage to reduce pain and for disciplinary purposes. Topical use of ice or cryotherapy gel bags, which are sold at any pharmacy, can effectively combat pain and swelling. Their use is also possible at a later date from the operation.

For the first 2-3 weeks, physical therapy is limited to performing movements in adjacent joints - the elbow and wrist; starting from the 3rd week, a gradual onset of rotational movements is possible. Full amplitude is restored by 6 weeks after the intervention. Physical activity is not allowed before there is a clear x-ray picture of fusion, which usually occurs by 3 months. The decision to remove metal fixators is made no earlier than 2 years from the date of surgery.

Instability and dislocations are the most common injuries to the elbow joint.

Causes
Symptoms and signs

Treatment

Bandages and orthoses

What is a forearm dislocation

The most common injury to the elbow joint is a forearm dislocation. After a dislocation, the elbow joint often remains unstable.1

When a dislocation occurs, the ligaments that stabilize the elbow joint are torn. Sometimes the joint capsule and muscles also rupture. The severity of the dislocation is determined by the displacement of the bones relative to each other. The greater the displacement, the more pronounced damage to the ligamentous apparatus has occurred.

The figure shows the right elbow joint, lateral view. The figure shows the ligamentous apparatus that is damaged in the event of a dislocation.

In some cases, the dislocation is accompanied by a fracture of the bone or bones that form the elbow joint. This condition is called fracture dislocation.

Elbow instability

Instability means that the ligamentous apparatus is no longer able to maintain bone mobility within physiological limits. Obviously, this negatively affects work ability. Instability causes pain and promotes damage to articular cartilage, which can lead to premature development of arthrosis.

Symptoms and signs: Pain and swelling

When a joint is dislocated, it takes on an unnatural configuration and its mobility is severely limited. Then pronounced swelling appears. An attempt to move is accompanied by severe pain. Often the pain also spreads to adjacent segments of the limb. As a result of nerve malnutrition or damage, numbness and loss of sensation below the level of the elbow joint may occur.