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Condylar fracture sprouts
05-09-2009
Damage condylar sprouts in second place in the structure of mandibular fractures. This is due to the fact that when struck on the chin from front to back is broken neck mandibular condylar sprouts, and in case of application of force to the lateral parts of the body, the branches or the chin to the most vulnerable is the base condylar sprouts, along with the angle of the mandible. The mechanism of fracture and in fact and in another case - the bend. Should be recalled that near the base of the appendix condylar cross-sectional area of bone in the lateral (naruzhnovnutrennem) direction is much less than in the anteroposterior. In the area of the neck of the mandible, these relationships are diametrically opposed. At the turn of the condylar sprouts essential for the removal of bone fragments is the impact force, direction of the force, the slope of the plane of fracture (from outside to inside or inside to the outside) and the position of the mandible at the time of impact of traumatizing force. Offset smaller fragments is due to reduction of the external muscles of pterygium. Greater otlomok pulled up all the other masticatory muscles. There is a shortening of the branches of the jaw. At the turn of the appendix base condylar fracture crack begins from cuttings of the mandible, passes down and ACA-D, ie in an oblique direction. The level of fracture of the outer and inner compact discs do not match. Features of the displacement of bone fragments will depend on which of the plates of the fracture line passes above - on the outside or inside. The latter depends on the bone during bending impact strength, due to the direction and force of impact. If the bone on impact bend outward, either-tion change on the outside of a compact plate is lower than on the inside. Gap fracture in this case is a slant, going from the outside inwards and upwards (ris.4.12, a). In this case, large otlomok moves in the direction of change, ie posteriorly under the influence of lateral and medial pterygoid muscles healthy side. This will be facilitated and posterior group of fibers of the temporalis muscle on the side of the fracture. In addition, under the influence of masticatory, temporal and medial pterygoid muscles on the side of the fracture, he will move upward. There will be a shortening of the branches of the jaw, which will inevitably affect the bite. Trim up big otlomok small otlomok pushes outward and somewhat backward slant on the plane of each of the fragments and prevent his return to the place under the influence of the external muscles of pterygium. Chin-division of a large fragments will move downward under the influence of the anterior muscle groups. On the healthy side teeth will be separated (or contact them - loose), and on the side of the fracture are closely in contact. As the head of the mandible is fixed in the glenoid cavity, the end of the small fragments, the call to the line of fracture is displaced outwards against the direction of traction outside pterygium muscle. The head of the mandible it may develop so that, with the glenoid cavity (disc) will be in touch only the lateral condyle. Looking ahead, we can say that patients with such fractures can sometimes be cured by conservative (orthopedic) methods.
When the bone inward bending under a force line fracture on the outside of a compact plate is higher than on the inside, and a crack fracture has a slant going down the outside and inwards (ris.4.12, b). In this situation, the end of the small fragments will move inside and in front due to the reduction of the lateral muscles of pterygium on the side of the fracture. This contributes to a large otlomok which, shifting upward and backward (see above), crush small otlomok inside, slipping on his break. Value dentitions will not differ from that described above. And in the first and the second case, a small fragment is not always loses contact with the great.
Fractures of the neck of the mandible can be transverse and oblique. In oblique fractures, the fracture line outside the compact disc is usually higher than the fracture line inside the compact disc.
In transverse and oblique fractures of the small otlomok increasingly shifted within a few anteriorly, combined with dislocation of the head of the mandible. This is due to the reduction of the lateral muscles of pterygium on the side of the fracture. In oblique fractures with the location of the bevel slot from the outside down and medially dislocated head of the lower jaw also helps a great otlomok, who pulled up, slides on the wound surface of the small fragments, otdavlivaya it medially. Thus the end of the large fragments can push the smaller of the glenoid cavity anterior to the articular tubercle. The higher the fracture line, the probability of dislocation of the head increases. In the case of the displacement of small fragments inwards from the branches in turn as the base of condylar the process, and at the neck of the mandible reponirovat it in the correct position with conservative methods are not feasible. At the turn of the head of the mandible is often broke off of the medial condyle, which is at break capsules temporomandibular joint is shifted inwards and anteriorly.
Intra-articular fractures are accompanied by often severe pain in the joints, increasing during the movement of the jaw. Malocclusion, usually slight and is only possible in the case of dislocation of small fragments. In this case the teeth on the healthy side and in the frontal section not in contact, and the average number of rejected line in the direction of fracture.
At the turn of the appendix defines a small condylar soft tissue swelling, pain on palpation trestle in front of the ear, and with a displacement of small fragments may be a slight bulging of lateral soft tissue in this area. Sometimes you can palpated the end of small fragments in the form of sharp spikes. On palpation anterior wall of external auditory canal at the time of opening-closing motion of the mouth articular head or absent (rarely), or much smaller in amplitude (more often) than in the healthy side. This is due to the fact that small otlomok is influenced by only the lateral muscles of pterygium. Patients can celebrate in this zone some soreness. Very rarely in condylar fracture processes in the moment of impact occurs perforation wall of external auditory canal sharp end of large fragments. Thus there is bleeding from the ear.
Careful examination of the external auditory canal can detect small ragged wound of the skin of his lower wall and exclude us bleeding with a fractured skull (temporal bone pyramid), which may also be bleeding from the ear in case of rupture of the eardrum. When opening the mouth, chin deviates to the side of a fracture, here is biased and the average line. In the case of displacement of bone fragments and, hence, shortening the length of the branches of the mandibular teeth contact point on the side of a fracture almost to the midline. On the healthy side contact of teeth missing. When you try to forcibly interdigitation hands sometimes possible to ensure that the contact come large and small molars, first on the side of the fracture, and then - on health. Lateral movement in a healthy direction are severely limited or absent, as they are carried out mostly with the unilateral reduction of the lateral and to a lesser extent the medial pterygoid muscles on the side of the fracture. In the diagnosis of condylar fracture of the appendix is important x-ray, which allows to determine the nature of the displacement of small fragments, the localization of the fracture line, relationship of the articular head and the glenoid cavity, which is crucial when planning the treatment of the patient
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