Few people know where the tooth process is located.
Most vertebrae have seven processes: spinous, four articular and two transverse. But in the cervical spine there is a vertebra with a special structure. He has one shoot more than all the others. This is the second cervical vertebra. Its eighth process is directed upwards.
Anatomical location
The tooth-like process is articulated with the first cervical vertebra called the “atlas” because it holds the base of the skull on itself . Between these vertebrae there is a movable joint. Its medical name is Atlanto-Axial. Figuratively speaking, the ring of the first cervical vertebra is worn on the dentate of its lower neighbor. That is why the neck of a person is so mobile. Almost 70 percent of all head rotations occur at this joint. And the tooth-like process is the point of rotation of our neck.
What caused the occurrence?
The appearance of the dentoid process is due to evolutionary reasons, because a person (like a number of other vertebrates) needed a quick and complete overview of the space around him to survive. However, the Atlanto-axial articulation is very vulnerable. Where there is a high degree of mobility - there is also a risk of pathological displacements, fractures, hypermobility. This joint is surrounded by a strong ligamentous apparatus, which ensures the strengthening of the dentoid process of the vertebra during physiologically normal movements. But prolonged or sudden pressure in excess of normal can lead to a violation of its integrity.
What are the problems with the second cervical vertebra fraught with?
In case of fractures of the second cervical vertebra, if there is no displacement of the process, the symptoms of this pathology are not obvious, and sometimes completely absent. About half of these fractures go unnoticed in the acute period, and almost a third are diagnosed only after two to three months, and sometimes years pass before this fracture is established in the patient. Doctors say that even radiography of the upper cervical spine is very problematic, since images of other bone structures are superimposed on the first and second vertebrae.
However, this is a very significant trauma, in which the displacement of the tooth-like process and atlas often occurs together with the skull in the direction of the spinal canal. And this leads to growing problems with motor activity, to the formation of a craniospinal syndrome in the patient, sometimes with a fatal outcome.
With the asymmetry of the tooth process of C2, very often patients have headaches that can last a long time.
Statistics
About 20 percent of fractures of the dentoid process are complicated by damage to the integrity of the spinal cord, and about seven percent lead to the worst outcome - the death of the patient. At the same time, about 8-15 percent of all cervical fractures are of this type. Risk groups are children under eight years of age and older people over seventy.
Damage to the dentoid process is so serious in its consequences that doctors consider all patients with suspected patients as those who already have a fracture. That is, the cervical spine is immobilized and delivered to the vertebrological emergency center (or another medical facility where there is a neurosurgical or traumatological department) in a neutral position.
Types of Fractures
Thanks to computed tomography, today doctors have the opportunity to accurately determine which of the following types can be attributed to a fracture of the dentoid process of the vertebra:
- The first type - in this case, an oblique fracture of the apex of the dental process occurs at the site of attachment of the pterygoid ligament. It is considered very rare.
- The second type - with it, the fracture line intersects the narrowest part of the "tooth", that is, the junction of the dental process and vertebra. In this case, the stability of the articulation of the axis and atlas is lost. And comminuted fractures of this type significantly complicate the treatment process.
- The third type. Here, the fracture line runs along the vertebra itself, starting from the base of the dental process. The stability of the joint is also violated.
The clinical picture of fractures of the second cervical vertebra
With these fractures, the clinical picture is very wide: from minor pain when turning the head and to an instant fatal outcome. If a fracture occurs without or with a slight displacement, the patient may experience slight pain in the upper part of the neck, which increases slightly with turns of the head. This happens with asymmetry of the dentoid process.
Rapidly disappearing pain during swallowing may also be present; neck mobility may be somewhat limited. Pain can occur with wide open jaws. In addition, all these sensations can quickly pass, and the patient begins to behave as usual. But doctors warn that the apparent well-being in this fracture is life-threatening. A careless step, a sudden push, etc. is enough - and a secondary displacement of the broken tooth process, displacement of the upper cervical vertebra and compression of the spinal cord will occur. And then the symptomatology will be sharply expressed, up to the loss of consciousness.
If there was a significant displacement of the dental process in the second type, then symptoms of a compressed spinal or oblong brain, transmitted vertebral arteries are possible. This may be tetraparesis, weakness or numbness of the extremities, upset sensation, impaired function of the pelvic or respiratory organs. Symptoms such as impaired speech, disturbance of swallowing movements, difficulty in opening the mouth and impaired taste can join them. Severe symptoms characteristic of spinal cord injury include respiratory failure or the development of cruciate palsy.
What is characteristic?
For such fractures of the dentate process (photo below), the so-called late spinal disorders are characteristic, which develop as a result of compression of the spinal cord by the back of the upper cervical vertebra with continued displacement of the tooth process as a result of its secondary shifts.
In case of fracture of the dentoid process without its displacement, the delayed clinical picture (when the established diagnosis did not follow on time due to the fact that the patient did not consult a doctor) may consist in aching pain in the back of the head or upper neck. These pains develop during movement and subside at rest. Difficulty in movement of the neck, dizziness, numbness of the face. The patient unfolds all over to look around.
But this can also manifest subluxation of the dentoid process.
Fracture diagnosis
Diagnosis of all injuries localized in the upper cervical region is carried out according to a strict scheme. If it is not possible to conduct an immediate computed tomography of the cervical spine, the patient is sent to a radiograph of this area in a lateral projection through an open mouth. Also, this study can be carried out in the position of flexion or extension of the neck. Since neck movements in cases of suspected fracture are potentially dangerous for the patient, these studies must be carried out under the supervision of a physician and not exceed the limits in which the patient has the ability to bend or straighten the neck.
It is relevant to conduct an x-ray in a bent and unbent position, especially for chronic fractures, since with a straight neck position the vertebral ratio in the pictures is likely to be normal.
If, despite these manipulations, the diagnosis is difficult, doctors resort to frontal and sagittal zonography or axial computed tomography. These are special studies that help improve the accuracy of the images needed to diagnose areas of the spine.
Fracture treatment
In the acute period of decentration of the dentoid in the upper part of the cervical spine often include immobilization, i.e. immobilization of the patient’s neck. The picture of treatment depends on the type of injury. In general, it must be remembered that manipulations involving the patient's head tilted forward are very dangerous here, as this can lead to trauma to the spinal cord. In general, treatment involves the removal of vertebral displacement and stabilization of the joint.
So, with an injury resulting from diving upside down or falling on the head of a heavy object, a plaster cast is applied, which the patient wears for about six months. Fusion is slow. Also, the patient is prescribed therapy with the Halo apparatus for three to four months.
Also, in case of fractures of the dentoid process without displacement, traction on the Glisson loop is used for one or one and a half months, after which a thoracocranial gypsum corset is applied, which must be worn from 4 to 6 months.
In traumatic spondylolisthesis of the second cervical vertebra, called the executioner's fracture, skeletal traction in the extension position (i.e., spinal traction) is used for three weeks, after which the patient is given a thoracocranial gypsum corset for three months. It also uses the Halo for up to four months.
Neck injury prevention
Avoid fractures of the upper cervical vertebrae will help general recommendations that are suitable in general to prevent neck injuries. First of all, compliance with safety requirements and rules. Also, while relaxing in nature, in no case should you dive headlong down into the water, or swim under the influence of alcohol.
Often, fractures of the two upper vertebrae occur during an accident, so prevention in this case will be strict adherence to traffic rules, checking the car for technical serviceability, the presence of airbags, etc.
First aid for suspected fracture of the second cervical vertebra
Unfortunately, this type of injury always happens suddenly. As we have already mentioned, such a fracture may go unnoticed, or it may immediately manifest in the most serious form. This may be an accident, an accident while camping, a head injury when an elderly person falls. Often, first aid is required for the victim to be in a safe position and wait for the ambulance to arrive.
Types of accidents
In general, all accidents with neck injuries can be divided into injuries, injuries of the intervertebral discs, fractures, dislocations, sprains and bruises. But the main point is that all neck injuries are extremely dangerous, therefore, neck movements should not be allowed until the doctor arrives, since in the presence of vertebral fractures the spinal cord can be injured.
Naturally, people around cannot establish the nature of the injured person. Therefore, one must act in accordance with the strict rules of first aid for these cases. It is urgent to call an ambulance - the patient must urgently be taken to the hospital for diagnosis and treatment.
For any injuries of the cervical spine, the first thing you need to do is rest with the immobilization of the cervical spine. If there is no danger to the victim and he is in a horizontal position, then it is better not to move him or even stop his attempts to rise. If there are open wounds in the cervical spine, they should be washed and an aseptic dressing applied if possible (for example, a first-aid kit in a car).
What else relates to first aid?
Also, first-aid treatment for injuries of the dentate process includes urgent tetanus prophylaxis and the introduction of drugs that reduce the symptoms of the shock state of the victim. After the ambulance arrives, the medical team examines and transports the patient in a prone position on an even shield. A special splint will be applied to the cervical spine or ambulance staff will perform splinting from the crown of the head to each of the patient’s shoulders. In this case, any movements of the victim’s body are carried out as carefully as possible in order to prevent possible injury to the spinal cord. Such a patient will be hospitalized and examined urgently.