Joint dislocation

Introduction to joint dislocation Dislocation of joints refers to the loss of normal correspondence between the articular surfaces of the various bones that make up the joint. Clinically, it can be divided into dislocation, congenital dislocation and pathological dislocation. After dislocation of the joint, soft tissues such as joint capsule, ligament, articular cartilage and muscle are also damaged. In addition, the joint around the joint is swollen and may have hematoma. If it is not reset in time, the hematoma is mechanized and the joint is stuck, causing the joint to lose function to different degrees. basic knowledge The proportion of patients: 0.002%-0.005% (in patients with joint trauma, the incidence rate is about 5-10% in joint trauma patients) Susceptible people: no specific population Mode of infection: non-infectious Complications: fractures, external humeral neck fractures, ossifying myositis, traumatic arthritis

Cause of joint dislocation

Dislocation of the elbow joint (40%):

Dislocation of the elbow joint is a common injury to the elbow, which occurs mostly in adolescents, and occurs in adults and children. Due to the complex type of elbow dislocation, severe damage to other bone structures or soft tissues of the elbow, such as the internal humeral fracture, the ulnar olecranon fracture and coronoid process fracture, and the damage of the joint capsule, ligament or vascular bundle. Most of them are posterior dislocation of the elbow or posterior lateral dislocation.

Dislocation of the shoulder joint (25%):

Dislocation of the shoulder joint is divided into anterior dislocation and posterior dislocation according to the position of the humeral head. The anterior dislocation of the shoulder joint is common, often caused by indirect violence. For example, when the fall, the upper extremity abduction and external rotation, the palm or elbow touches the ground, and the external force impacts along the longitudinal axis of the humerus. The humeral head is from the subscapularis and the greater muscle. The weak part avoids the joint capsule and dislodges forward and downward to form a anterior dislocation. The humeral head is pushed under the scapula condyle and forms a dislocation under the condyle. If the violence is large, the humeral head moves forward again to the subclavian, forming a dislocation of the subclavian. Posterior dislocation is rare, mostly due to the anterior and posterior violent effects of the shoulder joint or the landing of the hand when the internal rotation of the shoulder joint falls. After dislocation can be divided into scapular gangue and subacromial dislocation, shoulder dislocation, such as improper treatment in the initial stage, habitual dislocation can occur

Hip dislocation (25%):

The disease is a serious injury because the hip joint structure is stable and must have a strong external force to cause dislocation. Soft tissue damage is also severe at the time of dislocation. And often combined with other parts or multiple injuries. Therefore, the patients are mostly young adults with strong activities. Generally divided into three types of front, back and center dislocation. After dislocation, the femoral head was located on the Nelaton line (the anterior superior iliac spine and the ischial tuberosity line) before the dislocation. The person who is off the line is the posterior dislocation. The femoral head was squeezed toward the midline, breaking through the acetabulum and entering the pelvis as a center dislocation. Later dislocations are the most common of the three types. This injury should be treated as an emergency, and the earlier the reset, the better the effect.

Joint dislocation prevention

The main prevention of this disease is to strengthen labor protection and prevent trauma. Before physical exercise, adequate preparations should be taken to prevent injury. Children should avoid pulling hard.

1. Fully warm up

Fully warm-up activities before exercise, improve the excitability, responsiveness and resistance of muscle tissue, and gradually increase the degree of confrontation, which is helpful to reduce joint dislocation.

2. Homeopathic roll

Some self-protection measures for professional athletes in the fall are also worth learning by ordinary people. For example, when a volleyball player saves a ball or a football player falls after a collision, he will roll over and change his hand directly to the palm of his hand and gradually roll over the elbows and shoulders. Sometimes, athletes roll on the ground for several laps, as if they are stressed, but they can stand up and continue to fight. The reason is that the huge impact when they land is shared by multiple parts of the body during the tumbling, so Will focus on a certain location and cause serious damage.

The disease is caused by traumatic factors, no special preventive measures, the focus of clinical prevention and treatment lies in early diagnosis and early treatment, the treatment is simple, the patient suffers little, the treatment result is good; and the missed diagnosis makes the fresh dislocation turned into stale Sexual dislocation, the treatment is complicated, the treatment is long, the patient suffers greatly, and the treatment result is poor. Therefore, the clinical orthopaedic surgeon should be alert to the possibility of dislocation after the joint. For suspicious cases, the X-ray film should be taken or the chest X-ray should be taken. If necessary, the joint CT scan should be performed.

Joint dislocation complications Complications, fractures, external humeral neck fracture, ossifying myositis, traumatic arthritis

The disease is most often associated with fractures, nerve injuries, etc., such as shoulder dislocation cases about 30 to 40% with large nodular fractures, can also occur humeral surgical neck fracture, or humeral head compression fracture, sometimes combined with joint capsule or scapula Avulsion from the previous attachment, poor healing can cause habitual dislocation, biceps femoris tendon can slip backward, causing joint reduction disorder, the medial bundle of phrenic nerve or brachial plexus can be compressed or pulled by the humeral head. Causes neurological dysfunction and can also damage the radial artery. Therefore, you should pay attention to whether there are other combined injuries during the examination.

The complications of joint dislocation are divided into early and late categories according to the nature of time:

(1) Early complications

1. Fracture is a common complication of dislocation, which occurs mostly in the vicinity of the joint, or in the dislocation joint itself. There are also a few limbs that occur in dislocation. Such as shoulder dislocation and tibiofibular tuberosity fracture, scapular fracture, humeral anatomical neck and surgical neck fracture, humeral shaft fracture.

2. Although nerve injury is a rare complication of dislocation, once it occurs, it will cause adverse results in the recovery and prognosis of dislocation. Such as hip dislocation and sciatic nerve injury, knee dislocation and common peroneal nerve injury.

3. Vascular injury is one of the rare complications of dislocation. If large blood vessel damage occurs, the swelling is rapid and the patient is shocked quickly. Therefore, emergency measures must be taken and cannot be delayed.

4. Open dislocation is also rare. If it occurs, it will cause infection of the dislocated joint. After joint infection, the prognosis is poor.

(two) late complications

1. Ischemic necrosis of the bone damages the joint capsule, ligament or related muscles due to dislocation of the joint, which affects the blood supply to the bone. In the long run, the bone may be necrotic due to lack of blood supply, causing persistent joint pain.

2. The mechanism of ossifying myositis on ossifying myositis Most people believe that the periosteum is damaged. The bone cells in the periosteum are free from the hematoma around the joint and ossified in the hematoma.

3. Joint stiffness due to dislocation at the time of severe damage to the articular cartilage surface, joint capsule or concurrent fracture. The bone healing of the posterior articular surface is called bony stiffness, intra-articular stiffness and complete stiffness. The scar contracture or mutual adhesion of the joint capsule and ligament is called extra-articular and non-sterile, and the elbow joint, the ankle joint, the shoulder joint and the knee joint are common.

4. Habitual dislocation joints use the joints too early, the soft tissue around the joints or the cartilage damage of the joints are not well restored, causing the joints to loosen, the fascia is loose, causing joint instability, occasionally minor injuries, causing Dislocation.

5. Traumatic arthritis often occurs when the articular cartilage surface is damaged during dislocation, resulting in dislocation of the joint surface. In the case of the lower limbs, the joint surface is subjected to external forces such as friction and compression during load or movement, causing continuous damage to the joint surface. For a long time, the joints are painful when they are heavy, when they are tired, they are aggravated, the pain is relieved after rest, and the x-ray film has osteophytes.

Symptoms of joint dislocation Common symptoms Joint pain shoulder test positive elbow joint dislocation joint sprain joint pain sore joint pain ankle joint swelling joint swelling swelling pain joint capsule injury

Dislocation of the joint can only occur when the soft tissue such as the joint capsule, ligament and tendon is torn or accompanied by a fracture. It has the specific symptoms of general injury and dislocation. After the injury, the joint is dislocated, painful, difficult to move or unable to move. If the force is sufficient, almost any bone can be pulled and knocked from its joints. If the basketball player is hit by the ball at the end of the finger, the joint can be dislocated, the rugby player can be hit when throwing, and the force of the strike can dislocate the shoulder joint. Dislocation usually affects active joints such as ankles, knees, hips, wrists, and elbows, but the most common are shoulder and finger joints. Inactive joints, such as joints in the pelvis, can also be separated when the ligaments that hold the joints together are pulled or torn. Dislocation of the vertebra can be life-threatening if it damages the nerve or spinal cord. Dislocation of the dominant vertebra occurs at the spinal trauma, which can lead to paralysis.

General symptoms

(1) The pain is obvious, and it is aggravated when the limb is active.

(2) Swelling caused obvious swelling of the joint due to bleeding and edema.

(3) dysfunction After the dislocation of the joint, the structure is abnormal and the joint loses its normal function.

2. Special performance

(1) Deformity of the limb after the dislocation of the deformed joint, such as rotation, adduction or abduction, and the appearance of the limb becoming longer or shorter. The normal bony mark of the joint changes.

(2) Undistorted muscles and ligaments can maintain the dislocated limbs in a special position after elastic dislocation joint dislocation, and have a feeling of resistance and elasticity during passive movement.

(3) The initial joint stenosis of the joint stenosis is easier to be touched, but it is difficult to be touched when the swelling is severe.

Joint dislocation examination

The diagnosis of dislocation of the joint is not difficult. Generally, the diagnosis can be made according to its medical history and clinical manifestations, as well as simple physical examination. However, the clinical application of the auxiliary examination can more clearly understand the dislocation, including whether the surrounding bone is damaged. .

X-ray examination: It is important to determine the direction of dislocation, the degree, and the presence or absence of a combined fracture.

Diagnosis and diagnosis of joint dislocation

The diagnosis of this disease is relatively easy, the most important clinically is to identify the presence of combined injuries, the most common is fractures, such as shoulder dislocation cases about 30 to 40% with large nodular fractures, can also occur humeral surgical neck fracture, Or the humeral head compresses the fracture, so a detailed analysis should be made in the diagnosis of the patient's clinical manifestations. If the presence of the fracture is suspected, X-ray examination is needed, and the X-ray examination can confirm the diagnosis.

Diagnosis of joint dislocation

(1) There is a history of obvious trauma.

(2) The clinical manifestations are joint pain and swelling, deformity, elastic fixation and joint stenosis.

(3) X-ray examination can clearly identify the location, extent, direction of the dislocation and the presence or absence of fracture and displacement.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.