The cervical vertebra is divided into three parts: upper segment, middle segment and lower segment, and the operation methods of different segments are slightly different. Key points of operation: during the whole process of bone setting, ensure that the "joint stress point" does not leave the reduction thumb, and complete the reduction within the natural range of the patient's cervical vertebra. After successful reset, the thumb will feel vibration or beating, with or without noise.
Atlantoaxial joint dislocation:
1 The connection with the second vertebral body of cervical vertebra is atlantoaxial joint. Because of its special shape, it is classified as a special cervical vertebra. It is characterized in that the atlas is located at the uppermost end of the spine, and the whole skeleton is irregular and annular, with no vertebral body and spinous process. It is mainly composed of the lateral mass on both sides and the anterior and posterior arches connected between the lateral mass. The lateral mass is the site of bone hypertrophy on both sides, on which there is a articular fossa to support the skull, forming an atlantoaxial joint with the occipital condyle, and the lower articular surface is connected with the shaft.
The axis is the second cervical vertebra, which is similar to other cervical vertebrae in shape, but there is an upward protruding odontoid process on the vertebral body, called odontoid process. The odontoid process has a narrow root and a articular surface in front, which is related to the articular surface behind the anterior arch of atlas. There are interwoven ligaments and other soft tissues around the two joints, but there is no intervertebral disc between the two vertebral bodies. Therefore, the joint of two vertebrae has a larger range of motion than other joints.
Etiology and pathology:
Due to the special structure and connection of atlantoaxial joint, it is easy to cause injury and dislocation under the action of external force. In severe cases, it is easy to cause odontoid fracture or spinal cord and nerve injury, causing high paraplegia.
Symptoms and diagnosis:
Anterior dislocation of atlas is more common in atlantoaxial joint dislocation. After dislocation, the head can't support much, the head is low forward, and it hurts locally. People often walk with their chin supported by their hands, which leads to head motor dysfunction. In severe cases, limbs are numb and sore, and Hoffman test is positive. X-ray lateral film shows dislocation and obvious local tenderness.