Impact sign

Introduction The impact sign can occur at any age from the age of 10 to the old age. Some patients have a history of shoulder trauma, and a significant number of patients are associated with long-term overuse of the shoulder joint.

Cause

(1) Causes of the disease:

Abnormal morphology of the anterior and posterior aspect of the acromion, formation of callus, formation of epiphysis of the greater tibial tuberosity, hypertrophy of the acromioclavicular joint, and other causes of a decrease in the distance between the acromion and the humeral head can cause subscapular structures. Squeeze and impact. Most of these impacts occur in the first 1/3 of the shoulder and under the acromioclavicular joint. Repeated impacts cause damage, degeneration, and even tendon rupture of the bursa and tendon.

(2) Pathogenesis:

The impact sign is defined as: the clinical symptoms of the subacromial joint due to anatomical reasons or dynamics, in the lifting and abduction of the shoulder, due to the impact of the tissue under the shoulder.

Pathological findings: According to the pathological manifestations of the impact sign, it can be divided into three phases.

Phase 1: Also known as edema and bleeding, can occur at any age. Exercising over-use and cumulative damage to the shoulder joints caused by over-the-arm work, such as stencil paint and decoration work, and sports such as gymnastics, swimming, tennis, and baseball throwing are common causes.

In addition, this issue also includes a one-time history of simple shoulder injury, such as edema and hemorrhage of the supraspinatus tendon, biceps femoris head and scapular sac caused by severe physical contact or severe falls. Although the muscle strength is weakened due to pain in this period, there are some typical symptoms of rotator cuff tear. Physical examination is not easy to find signs such as pain arc sign, gravel sound and positive chronic impact test. Injection of lidocaine under the acromion can completely relieve pain. X-ray examination generally showed no abnormal findings, and arthrography could not find rupture of the rotator cuff.

Phase 2: Chronic tendinitis and bursal fibrosis, more common in middle-aged patients. Repeated impact under the acromion causes fibrosis of the bursa, thickening of the cyst wall, and repeated tendon injury of the tendon, which is usually accompanied by fibrosis and edema. Thickened bursae and tendons occupy the subacromial gap, and the supraspinatus muscle outlet is relatively narrow, increasing the chance and frequency of impact, and the onset of pain symptoms can last for several days. Shoulder fatigue and discomfort are still felt during pain relief, and physical examinations are more likely to detect pain and positive impact tests. If there is biceps brachial gingivitis, the Yergason sign is positive, and the biceps brachial sacral tendon extension test can also cause pain. Pain under the acromial lidocaine injection test can temporarily relieve pain.

The third stage: the rupture period of the tendon, the main pathological change is the partial or complete rupture of the tendon on the basis of repeated injury and degeneration of the supraspinatus tendon and biceps brachii. After the age of 50, the average age of the combined partial tendon rupture reported by Neer II was 52 years old, and the average age of patients with complete rupture was 59 years old. The degree of tendon degeneration and repair ability are related to age factors. It should be noted that not all impact signs can cause rotator cuff rupture, and not all rotator cuff injuries are caused by impact signs. The rotator cuff rupture caused by the impact sign, only about 1/2 of the history of trauma, only a few patients have a more obvious or heavier history of trauma, most of the cases of injury strength is actually less than the complete rupture of the rotator cuff The external force required indicates the importance of the tendon degeneration factor itself.

At the beginning of the rupture of the rotator cuff, the pain is intermittent, and the onset of pain is closely related to the frequency of the impact. Symptoms worsened after work and at night, and were significantly relieved after rest. If there is chronic shoulder bursitis, the pain is persistent and intractable. The limb is weak due to shoulder pain, and the muscles of the external rotation muscle and the abductor muscle are weakened. In the sagging position of the limb, 90% of the external rotation muscle strength comes from the infraspinatus muscle. When the limb is tested at the abduction 90° position for the external rotation muscle strength, most of the external rotation muscle strength comes from the posterior part of the deltoid muscle. As the disease progressed, the muscles of the supraspinatus, infraspinatus and deltoid muscles showed muscle atrophy and muscle strength decreased. Physical mechanics examination is easy to find pain arc sign, gravel sound, positive impact test. In addition, the positive rate of arm fall arrest is also higher.

Ankle instability is also present in people with extensive rotator cuff tears. Complete tearing of the rotator cuff causes joint fluid communication between the ankle cavity and the acromion sac, but most patients still maintain a certain degree of mobility of the ankle. Incomplete rotator cuff rupture or long-term painful braking may cause joint stiffness and loss of function.

Arthrography is still the most reliable diagnostic method for complete rotator cuff rupture. However, neither angiography nor ultrasonography can show or determine the size of the rupture. Clinical physics examination showed that the supraspinatus tendon was obviously atrophied, the muscle strength was weakened, the arm fall was positive, and there was a biceps tendon rupture, and the X-ray showed that the peak-humeral head spacing was significantly reduced (0.5 cm). ), it is suggested that there is a large fracture of the rotator cuff.

The impact injury of the biceps tendon is generally associated with the injury of the supraspinatus tendon, and the extensive tearing of the rotator cuff can prompt the rapid deterioration of the biceps tendon injury. The impact sign 2 may be associated with the presence of biceps femoritis. In the second phase, partial or complete rupture of the tendon may also occur. The proximal tenderness of the nodular sulcus, the positive Yergason sign, and the biceps brachial sputum test positive for the biceps brachii are the manifestations of the biceps femoris head lesion. When the flexion elbow biceps resistance test is performed, if the muscle strength is significantly weakened, it means the possibility of rupture of the biceps tendon. Shoulder arthrography and arthroscopy help to make a definitive diagnosis.

an examination

Related inspection

Joint examination of the bones and joints of the extremities

The impact sign can occur at any age from the age of 10 to the old age. Some patients have a history of shoulder trauma, and a significant number of patients are associated with long-term overuse of the shoulder joint. The rotator cuff and the bursa are repeatedly damaged, and the symptoms are caused by edema, hemorrhage, degeneration, and even tendon rupture. The early clinical manifestations of rotator cuff bleeding, edema and rotator cuff rupture are similar to the confusion. Should the impact sign be identified with other causes of shoulder pain, and distinguish which stage of the impact sign, which is very important for the diagnosis and treatment of this disease.

Common symptoms of each period of impact:

1. Chronic dull pain in front of the shoulder: symptoms worsen during lifting or outreach.

2. Pain arc sign: Pain or symptom aggravation in the range of 60 ° ~ 120 ° on the affected arm. The pain arc sign is only present in some patients and is sometimes not directly related to the impact sign.

3. Gravel sound: The examiner holds the front and rear edges of the shoulder of the affected arm by hand, so that the upper arm can be used for internal and external rotation and flexion and swaying when flexing forward and backward. It is easier to hear with a stethoscope. . Obvious gravel sounds are more common in the impact of the second phase, especially in patients with complete rotator cuff fracture.

4. Muscle strength: The weakening of muscle strength is closely related to the late impact of extensive rotator cuff tear. Early in the rotator cuff tear, the shoulder abduction and external rotation weakened, sometimes due to pain.

5. Impact test: The examiner presses the patient's ipsilateral scapula with the hand down and raises the affected arm. If the pain occurs due to the impact of the large nodule of the humerus and the shoulder, it is positive for the impact test. Neer II believes that this test has great clinical significance for identifying the impact sign.

6. Impact injection test: 10 ml of 1% lidocaine was injected into the acromial sac under the acromion. If there is no shoulder joint dyskinesia before and after injection, and the symptoms of shoulder pain are temporarily completely disappeared after injection, the impact sign can be established. If the pain is only partially relieved after the injection and there is still joint dysfunction, the possibility of "freezing the shoulder" is greater. This method can be used to identify shoulder pain caused by non-impact signs.

Differential diagnosis

Shoulder pain refers to the pain in the muscles of the shoulders and shoulders. Among all the joints of the body, the shoulders may be the most versatile, and it has a lot of muscles and muscles, allowing your arms to do a wide range of activities, as well as the joints that are most prone to fatigue and disease. Many elderly people suffer from shoulder pain because of "shoulder periarthritis". After a long time, they are easy to form a mindset, thinking that shoulder pain must be a symptom of frozen shoulder. In fact, shoulder pain may also be caused by other more serious diseases.

Quadrilateral space syndrome is a series of clinical syndromes caused by compression of the posterior circumflex artery and phrenic nerve at the four-sided hole. Its main manifestation is the sensory disturbance of the lateral arm of the sacral nerve and the limitation of deltoid function.

Shoulder pain and shoulder discomfort is also known as the leaking shoulder wind, inflammation around the shoulder joints, fifty shoulders, and the shoulder joint dysfunction is also known as the frozen shoulder.

Shoulder activity is limited, more common with inflammation around the shoulder joint and shoulder dislocation.

Shoulder: The shoulder of the computer is called shoulder periarthritis (now less used), commonly known as the frozen shoulder. It is a chronic injurious inflammation of the shoulder muscles, tendons, bursae and joint capsules. Due to hyperplasia, roughness and internal and external adhesions, it is clinically characterized by pain and function limitation during activity.

The impact sign can occur at any age from the age of 10 to the old age. Some patients have a history of shoulder trauma, and a significant number of patients are associated with long-term overuse of the shoulder joint. The rotator cuff and the bursa are repeatedly damaged, and the symptoms are caused by edema, hemorrhage, degeneration, and even tendon rupture. The early clinical manifestations of rotator cuff bleeding, edema and rotator cuff rupture are similar to the confusion. Should the impact sign be identified with other causes of shoulder pain, and distinguish which stage of the impact sign, which is very important for the diagnosis and treatment of this disease.

Diagnosis can be established based on medical history, clinical symptoms, signs and tests, X-ray films, magnetic resonance, ultrasound, and joint angiography.

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