Displaced Bennett fracture. Closed intra-articular fractures. Number of injured areas

Bennett's fracture is considered the most common fracture of the base of the thumb and belongs to the group with displacement. It is an oblique fracture that passes through the base of the metacarpal bone. A smaller fragment of the articular surface, which, as a rule, has a triangular shape, remains in place, and the main part with the bone diaphysis begins to shift towards the radial-dorsal side. A Bennett's fracture is also called a boxer's fracture.

Causes

The main causes of such fractures are the following situations:

• Hitting the wrist with a heavy object.
• Impact on the axis of the finger.
• Strike with bent first finger.
• Falling on the palm with outstretched arm.
• Falling on a finger (for example, from a bicycle).
• Hitting a hard surface (for example, with incorrect punches from boxers).
• Strong palmar flexion of the hand.
• Sports injuries. For example, when performing gymnastic exercises.

Mechanism of injury

As a result of a blow directed at the axis of the thumb, the patient develops a dislocation in the area of ​​the small carpometacarpal joint and a fracture occurs at the base of the metacarpal bone. When a person is traumatized, the metacarpal bone is displaced slightly upward, as a result of which the triangular part of the ulnar edge of the base breaks off.

Symptoms

A patient immediately after a Bennett fracture has severe pain in the hand. In the area of ​​its dorsal surface and the wrist joint, there is marked swelling and hemorrhage. A characteristic sign of such a fracture is swelling in the area of ​​​​the elevation of the first finger and its base. On palpation of the hand occurs in areas of bone damage. When a patient tries to perform flexion and extension, adduction and abduction of the first finger with a Bennett fracture, a sharp pain appears. A person cannot carry out rotational movements with a brush and a finger.

Rolando fracture

The line of such a fracture is similar to the letter Y or T. With a Rolando fracture, fragmentation of the articular surface into 3 main parts is observed: a fragment of the body, volar and dorsal fragments.

Bennett and Rolland fractures are similar. With a Rolando fracture, the diaphysis is displaced much less, and therefore this type of injury does not belong to the category of traumatic fracture-dislocations.

Rolando's fracture line can be observed in several projections, which affects the choice of access for surgical care, and some bone fragments can be so small that they are not visible on the x-ray.

Reasons for getting a Rolando fracture

Rolando's fracture dislocation is also the so-called boxer's fracture. In most cases, these types of pathologies occur due to a pronounced effect on the hand by axial loads.

A boxing fracture is a consequence of an incorrectly executed (technically) blow with a specifically assembled hand: the second to fifth fingers are bent at the joints, while the thumb is bent, opposed and adducted. A fall on the radial (inner) part of the hand on the thumb brought to it can lead to a Rolando fracture. Such a pathology occurs 2 times more often than similar injuries, which are caused not by a fall, but by a shock effect.

Symptoms of a Rolando fracture

Signs of a Rolando fracture:

• aggravated by movements of acute pain in the area of ​​injury;
• swelling and hematoma in the eminence and base of the thumb;
• insignificant varus deformity of the first joint;
• violation of the functionality of the hand - sharply weakened retention and grip;
• the thumb is slightly bent and pressed to the hand, it cannot be taken away;
• on palpation of the joint, a characteristic crunch is possible;
• the load on the thumb is extremely painful.

The victim should not take his thumb away in order to recognize his injury. Such manipulation will not help to differentiate a bruise or a more complex injury. If a fracture occurs, then these actions can further injure soft tissues and increase the amount of displacement of bone fragments.

Fracture of Monteggi and Galeazzi

In the case of such fractures, the radius breaks in the lower zone. At the same time, there is a dislocation in the area of ​​the elbow joint with a rupture of the connective tissue. This is observed due to an indirect or direct blow to the forearm.

The causes of the above fractures are strong blows to the forearm area.

Galeazzi fractures most commonly occur in children. The injury is the result of a direct blow to the arm, and can also occur when falling on a straight arm. In such a case, bone fragments move forward, and the head of the joint in the opposite direction.

Collis fracture

This type of fracture affects the distal end of the radius. The nature of the damage is very diverse (fracture without splinters, extra- and intra-articular fractures, comminuted multi-comminuted fracture). Often such injuries are accompanied by a detachment of the styloid processes in the ulna.

A Collis fracture is often seen in older women. It can occur when falling on an outstretched arm, palm facing down. There may be no displacement, but most often the distal fragment moves to the dorsal-beam side. In most cases, a closed fracture is noted, however, if soft tissues are damaged, an open fracture is possible. In this case, the square pronator, median nerve, flexor tendons, interosseous branches of the radial nerve, and the skin can be damaged.

Smith's fracture

Smith's fracture belongs to the category of typical flexion fractures of the radius, when the hand is bent in the opposite direction. For the first time, this type of injury and its mechanism were described by the Irish surgical specialist Robert Smith. A displaced Smith fracture is often the result of a fall on the elbow. Comminuted fractures can be obtained at work, when working with heavy equipment, etc.

Treatment and prognosis

There are several methods for neutralizing a displaced Bennett fracture, as well as other fractures - conservative and operative. If the injury did not cause significant movement of parts of the bone, it is considered mild. In this case, there are no surgical interventions, and additional manipulations are limited to gypsum.

What else is involved in the treatment of a Bennett fracture?

If necessary, the joint is repositioned and fixed in the desired position under local anesthesia.

The most favorable prognosis is considered to be the location of bone fragments at a distance of 1 to 3 mm from each other. This distance is considered the best for the rapid fusion of fragments and the restoration of the functioning of the hand.

If it is impossible to hold the damaged parts and preserve the functioning of the hand by external influences, an operation is used for Bennett's fracture. One of these methods is skeletal traction.

We reviewed Bennett, Colley, Smith, Galeazzi, and Monteggi fractures.

The Bennett Fracture is perhaps the most famous fracture of the first metacarpal. In 1882, Edward H. Bennett (Edward Hallaran Bennett, professor of surgery at Trinity University Dublin, 1837-1907) in his work "Fractures of the metacarpal bones" described an intra-articular fracture with displacement, passing through the base of the first metacarpal bone. Bennett wrote that this fracture "passed obliquely through the base of the bone, separating a large part of the articular surface," and "the detached fragment was so large that the resulting deformity more closely resembled a dorsal subluxation of the first metacarpal bone." Therefore, it would be more correct to speak not about a fracture, but about Bennett's fracture-dislocation.

With a Bennett fracture-dislocation, the medial (aka proximal) fragment, which is held by the carpometacarpal and interosseous metacarpal ligaments, remains in place, and the body of the metacarpal bone (corpus metacarpale) with the rest of the articular surface is displaced laterally (to the dorsal-radial side) under by the action of the long muscle of the abductor thumb that does not meet resistance. That is, there is a dislocation or subluxation of the metacarpal bone in relation to the trapezoid bone (large polygonal bone).

Mechanism

This is, first of all, the action of a traumatic force along axis I of the metacarpal bone, which is in a position of slight adduction and opposition. This situation can occur when punching on a hard surface, for example, in boxers with an incorrect punch; when falling with support on the thumb; when the bicycle falls, when the hand covering the handlebar is in a position conducive to such damage. An intra-articular fracture of the base of the first metacarpal bone occurs, and under the influence of traumatic force and traction of the long muscle of the abductor thumb, further displacement occurs (dislocation or subluxation).

Clinic. Diagnosis.

The symptoms of a Bennett fracture are quite characteristic. Disturbed by pain, aggravated by movement, weakness, dysfunction of the hand. There is swelling, hemorrhage in the base and elevation of the thumb; deformation is determined. The thumb is adducted.

You should not cause unnecessary pain to the victim, trying to determine the reliable signs of a fracture.

Differential diagnosis should be carried out, first of all, with Rolando's fracture .

To determine the diagnosis allows radiography, performed in conventional projections.

Treatment.

Fracture-dislocation of Bennett is intra-articular and, of course, requires compliance with the relevant principles for the treatment of such fractures (dislocation or subluxation must be set, fragments should be ideally - if possible - matched). It is believed that the displacement of fracture fragments should not exceed 1 mm (some authors consider a displacement of 1-3 mm to be acceptable, provided that union occurs and the joint remains stable). Failure to comply with these principles will lead to the development of arthrosis with all the ensuing consequences. It should also be borne in mind that we are dealing with the first (thumb) finger of the hand. The function of the thumb is about 50% of the total function of the hand. Bennett in his work emphasized the importance of early diagnosis and early treatment for these fractures associated precisely with the possibility of losing the full function of the hand.

First aid is similar to that described in the article " boxer's fracture ».

With a slight displacement and degree of subluxation (less than 1 mm), which is relatively rare, the treatment consists in immobilization with a plaster or other (polymer) bandage for 3-4 weeks. X-ray control after 5-7 days is mandatory.

In case of unacceptable displacements, reposition and retention of fragments in the correct position until the fracture heals are necessary. Previously used methods of treating these injuries are finding fewer and fewer supporters.

Closed reposition by traction on the first finger and pressure on the base of the first metacarpal bone is usually successful, but it is very difficult to keep the fragments in the correct position with a plaster or other bandage. If we apply strong pressure on the metacarpal bone, we will cause the formation of a decubitus with all the ensuing consequences. If the pressure is less, we get a second displacement. The use of such techniques as a “gauze loop”, with the help of which pressure is applied to the metacarpal bone, and after the application of a plaster cast it is cut off, do not save the situation.

The traction treatment of a Bennett fracture described in many manuals is also unreliable. The entire traction structure is usually fixed to a plaster or other external bandage on the arm and its stability is low. With control radiographs, repeated displacement is usually found, and attempts to eliminate it by increasing traction are usually unsuccessful. If the pull is carried out by a spoke passed through the proximal phalanx of the thumb, then there is a high risk of infection, since there is usually mobility of this spoke.

Therefore, at present, closed or open (depending on the nature of the fracture) reposition and fixation with pins are usually used.

There are various methods of such manipulations. One of the best is the Wagner technique.

Wagner methods.

1. Closed technique.

Carry out reposition by manual traction for the finger and pressure on the base of the metacarpal bone; with a drill, a Kirschner wire is passed through the base of the metacarpal bone through the joint into the trapezoid bone.

X-ray control; if everything is successful, the needle is cut off at the skin (“bite”).

Impose a fixing bandage (gypsum, etc.); the brush is given a slight extension, and the thumb should be in the position of abduction (abduction).

Sometimes more than one Kirschner wire is required for secure fixation; additional spokes are inserted into other bones at different angles.

2. Open technique(with unsatisfactory results of a closed technique).

An arcuate incision begins along the dorsal surface in the projection of the first metacarpal bone and leads it to the palmar crease of the wrist, protecting the sensitive branches of the radial nerve.

To visualize the fracture, the soft tissues are partially exfoliated from the fragments and the first metacarpal-carpal joint is opened.

Reposition is carried out, leveling the articular surface, and a needle is inserted under visual control.

Quite often, fixation with a single wire is unreliable, and in this case, additional Kirschner wires of a smaller diameter are carried out.

Alternatively, fixation of the fracture can be achieved with a screw (2 or 2.7 mm).

After closing the wound, immobilization is carried out in the same way as with the closed technique.

Rehabilitation.

The fixing bandage is removed after 2-3 weeks, the wound is examined. The spokes can be removed. Reapply a fixing bandage and keep it up to 4-6 weeks from the date of surgery. (The timing depends on the nature of the damage and the results of the surgical intervention). After the termination of immobilization, the entire rehabilitation complex (exercise therapy, FTL, massage) is prescribed.

If a screw was used during the operation, and reliable fixation of the fracture was achieved in disciplined patients, after 2 weeks the deaf bandage can be replaced with a removable splint and therapeutic exercises can be started.

Complications of Bennett's fracture-dislocation.

Fracture union with displaced fragments and persistent subluxation can lead to painful arthrosis and dysfunction of the hand. After 6 weeks after the injury, reduction should no longer be applied. For malunion fractures, prior to the detection of degenerative changes in the joint (X-ray), Giachino proposed the technique of corrective osteotomy. If the phenomena of deforming arthrosis have already developed, then it is recommended to perform arthrodesis or arthroplasty.

Giachino corrective osteotomy technique. (From Giachino AA: A surgical technique to treat a malunited symptomatic Bennett’s fracture, J Hand Surg 21A:149, 1996.)

Postoperative management.

Immobilization with a fixing bandage should continue for 6 weeks, and active movements should be started if there are radiological signs of fracture union.

Metacarpal fractures meet quite often, especially fracture of the I metacarpal bone. It is necessary to distinguish between a fracture of the diaphysis and a fracture-dislocation of the base of this bone, called Bennett's fracture-dislocation, which is observed quite often and is always intraarticular.

Such fractures occur only as a result of indirect trauma - when falling on the first finger, which is in a straightened and adducted position, or hitting it. A fracture occurs if the traumatic force acts along the axis of the finger, simultaneously bending it. The first metacarpal bone rests against the underlying polyhedral bone, as a result of which a small piece of the base of the I metacarpal bone of a triangular shape breaks off, which remains in place, and the rest of the bone, due to adduction and continued action of the traumatic force, is displaced to the dorsal-radial side. With such an injury, as a rule, subluxation of the first metacarpal bone occurs. If at the time of injury I the metacarpal was in the allotted position, then a comminuted fracture of the base of the bone may occur. With a Bennett fracture, the function of the hand is significantly impaired, since the main movements of the first finger (adduction, abduction and comparison) occur in the metacarpal-carpal joint.

Rice. 45. Bennett's fracture.

Bennett's fracture is easy to diagnose. At the same time, they are based on the mechanism of injury (fell on an extended finger, hit a hard object with an extended finger, etc.) and the clinical picture. The deformity is clearly expressed, the finger is in the adducted position, there is a protrusion in the area of ​​the first metacarpal-carpal joint, the contours of the anatomical snuffbox are smoothed. On palpation, the edge of the displaced I metacarpal bone is easily determined. Local soreness is also detected here. If you pull the finger, the protrusion disappears, and when the traction stops, it reappears. Minor tapping on the fingertip causes pain, which is also determined by palpation of the area of ​​the metacarpal-carpal joint from the palmar side. Active and passive movements, especially finger abduction and comparison, are painful. Despite the possibility of accurately diagnosing a Bennett fracture, X-rays are required (Fig. 45).

Treatment. Taking into account the diverse function of the first finger, it is important to accurately compare the fragments, because even with the slightest displacement, the function of the hand will be significantly impaired. Comparison of fragments does not cause much difficulty, it is more difficult to keep them in the correct position.

Many ways of fixing the first finger in case of Bennett's fracture have been proposed. Comparison of fragments is performed under local anesthesia. 5-7 ml of 2% novocaine solution is injected into the fracture area. Reposition must be done by two people. After anesthesia, the patient is seated on a chair, the surgeon stands in front of the patient, with his back to his face. With one hand, he captures the area of ​​​​the wrist joint so that the first finger of this hand of the doctor is located at the base of the first metacarpal bone of the patient. Pressing the I finger on the end of the dislocated I metacarpal bone, the surgeon displaces it in the distal and ulnar direction. Feeling that the subluxation has been eliminated, with the other hand, with which he held the end of the finger, the surgeon removes the finger to the radial side. At this time, the assistant prepares the wire splint, bends it along the contours of the distal part of the forearm and the first finger, and bandages it to the forearm and wrist joint. In order to keep the metacarpal bone in the correct position, a dense cotton-gauze pad is strengthened between the splint and the base of the I metacarpal bone, then the splint is tightly bandaged to the finger. If the correct position of the fragments is determined on the control radiograph, then the splint is strengthened with additional rounds of cast bandages.

Fixation of the fragments after their comparison can also be carried out using a plaster cast. To do this, a splint 25-30 cm long and 10-12 cm wide is prepared. The surgeon holds the forearm and finger, the assistant lays the splint along the palmar and lateral surfaces of the forearm and finger. It should reach the interphalangeal joint. Between I and II fingers, the longuet is cut; with its free part, it covers the first finger from almost all sides. The longueta is strengthened with plaster bandages. Thus, a circular plaster cast is created. The surgeon holds the finger and forearm until the bandage hardens.

It is necessary to pay attention to one detail when comparing fragments. The first finger should not be abducted until the subluxation of the base of the metacarpal bone is eliminated, since during abduction the proximal end of the metacarpal bone will rest against the multifaceted bone and it will be impossible to eliminate the subluxation.

If the I metacarpal tends to be displaced and is poorly supported by a splint or cast, fingertip traction may be applied. To do this, a metal tire is bandaged to the plaster cast, which should stand a few centimeters above the top of the finger. A needle or a special pin is passed through the nail phalanx, for which a finger is pulled out with an elastic band attached at one end to the spoke and the other to the end of the tire. It is also possible to pass the wire transosseously through both fragments after they have been compared.

Immobilization of the finger with a cast or splint should last at least 5 weeks and can be stopped only with good consolidation of fragments, confirmed by radiographic. After removing the bandage, they begin to actively develop movements in the metacarpal-carpal joint. Assign a massage of the muscles of the hand and forearm, as well as physiotherapy and balneological procedures. The effectiveness of treatment is determined not only by the standing of the fragments and the nature of their fusion, but also, mainly, by the degree of restoration of finger mobility. As noted above, when adduction and juxtaposition of the finger are limited, the function of the hand is sharply disrupted, so it is necessary to actively restore mobility. Usually finger function and ability to work are restored within 7-8 weeks.

Dubrov Ya.G. Outpatient traumatology, 1986

A Bennett fracture is a fracture at the base of the first metacarpal that extends into the carpometacarpal joint. This intra-articular fracture is the most common type of thumb fracture and is almost always accompanied by some degree of subluxation or obvious dislocation of the carpometacarpal joint.

Possible symptoms

The symptoms of a Bennett's fracture are instability of the thumb joint, accompanied by pain and weakness in the grip. Characteristic features include:

• pain;
• edema;
• ecchymosis around the base of the thumb (especially over the knuckle).

Physical examination demonstrates instability of the thumb joint. The patient usually loses the ability to hold objects normally and perform tasks such as tying shoelaces and tearing paper. Another possible complaint is severe pain that occurs when touching various objects with the thumb.

Many important activities in daily life involve the thumb. In fact, about 50% of the functions that the hand performs are associated with it. These functions work normally only if the thumb is intact and moves normally. The knuckle of this finger allows for a wide range of motion while maintaining the stability required for gripping and holding.

If it is not possible to properly recognize and treat such a fracture, it will lead to unstable and painful arthritis of the joint, a decrease in the range of motion, and a significant decrease in the functionality of the hand as a whole. In this way, the proximal metacarpal fragment remains attached to the anterior oblique ligament, which is connected to the trapezius joint. This ligament ensures that the proximal fragment remains in the correct anatomical position.

The distal fragment of the first metacarpal bone occupies most of the surface of the first joint. Strong ligaments and tendons of the muscles of the hands pull this fragment out of the correct anatomical position. Tension from the APL and ADP muscles often results in displacement of the fracture fragments even when they are initially in their correct anatomical position.

Because of the aforementioned biomechanical features, Bennett fractures almost always require some form of intervention to ensure proper anatomical alignment and restore normal thumb function.

Causes of injury

This fracture is an oblique intra-articular metacarpal dislocation. It results from a force applied to a partially flexing metacarpal joint.

1. This can happen, for example, if a person hits a hard object hard with his fist or falls unsuccessfully on his thumb.
2. This injury often occurs as a result of falling off a bicycle, as the fingers tend to wrap around the grips on the handlebars.
3. It is also a common injury in car accidents, often occurring in drivers holding the steering wheel at the time of impact. When the car collides with an object, the thumb can get caught on the steering wheel while the hand rushes forward.

Some physicians refute the common belief that the APL tendon is not the deforming force in a Bennett fracture.

Fracture treatment

Although this fracture usually appears minor on radiographs, it can lead to severe and long-term hand dysfunction if left untreated.

In his original description of this type of fracture in 1882, Bennett emphasized the need for early diagnosis. X-rays and timely treatment should prevent dysfunction of the thumb and disruption of the hand as a whole.

In some cases, a fracture can result in relatively little joint instability and minimal joint subluxation (less than 1 mm). In such cases, effective treatment may require only closed reduction followed by immobilization and radiography.

Bennett fractures with 1 to 3 mm displacement of the trapezius joint may require closed repair and fixation with Kirschner wires. In this case, the wires are not used to connect the fragments of the fracture.

For more complex fractures where there is more than 3 mm displacement at the trapezius joint, surgery and internal fixation are usually recommended. Whether or not surgery has been used, the cast is used for 4–6 weeks.

The common knowledge for traumatologists of intra-articular Bennett fractures, which make up to 3/4 of all fractures of the base of the first metacarpal bone, frees from the need for a detailed description of their genesis, symptoms, and X-ray diagnostics.
However, it is important to emphasize that the displacement of the metacarpal bone with a larger or smaller fragment of its inner edge remaining in place is due to the mobility of the saddle trapeziocarpal joint, which does not have any noticeable “bone” stability; the latter is mainly supported by four ligaments, especially the palmar ray, the most powerful of them. Damage to all ligaments along with the capsule can lead to a "clean" dislocation. But much more often, the wide and strong palmar ulnar ligament, passing from the crest of the trapezoid to the ulnar edge of the base of the metacarpal bone, tears off and holds the fragment in the triangular bed, without preventing the displacement (subluxation, dislocation) of the metacarpal bone in the dorsal-radial direction.
The still widely promoted and commonly used techniques for the closed reduction of Bennett fractures by applying significant efforts with extension of the finger, its abduction and extension with
Simultaneous pressure from the rear on the base of the metacarpal bone, as experience shows, often does not bring the desired effect and often forces them to switch to open repositions. But even J. Charnley (1957) warned that the reason for the frequent failures of closed repositions of Bennett's fracture-dislocations is the pull of the finger along the length.
When repositioning fresh Bennett fractures, the problem is not so much in eliminating the displacement of the metacarpal bone - this can be achieved without much difficulty by various methods - but in the correct comparison of the fragments and in keeping them from repeated displacements. But it is the traction for the finger, its abduction and extension that can lead to the opposite effect, causing rotation of the palmar-ulnar fragment and the tendency of the metacarpal bone to shift from the articular area of ​​the trapezium. Because the neutral position for the trapezius joint is finger 1 opposition, effective anatomical reduction can be achieved by placing the finger in opposition with internal rotation and "screwing" the metacarpal into place. In this case, light adduction of the finger and light pressure from the rear will not interfere. Immobilization should be carried out within 4-5 weeks. More reliable (before applying a plaster cast) percutaneous transarticular stabilization with a thin Kirschner wire (1.2-1.25 mm) passed through the base of the metacarpal bone into the trapezium.
You can count on the success of a closed reposition if the damage is up to 10 days old, the optimal time is up to 3-4 days.
The functional outcomes of even ideally performed open reductions are somewhat worse than with closed reductions; but they are, of course, inevitable in case of failures of closed reductions or chronic displacements. Stabilization with two Kieshner wires - axial (through the metacarpal bone to the trapezoid) and transverse (through the metaphyses of the I and II metacarpal bones) - prevents shifts and rotations of the bones, facilitates the care of the wound and the finger. Knitting both fragments is required infrequently.
With the consequences of unrepaired or incompletely eliminated Bennett fractures and dislocations with pain syndrome, the most acceptable and reliable is arthro-
des trapeziocarpal joint in a functionally advantageous position. In some cases, you can resort to corrective osteotomy, as advised by S. Bunnell.