Pterygoid scapula is a relatively rare condition that often causes functional limitations or disorders of the upper extremities, affecting the patient’s ability to lift, pull, and push heavy objects, as well as some daily activities such as dressing, combing hair, and brushing teeth. In a normal person, the scapula is close to the chest wall, which is mainly accomplished by the synergistic contraction of the serratus anterior, rhomboid and trapezius muscles. If the anterior serratus muscle is paralyzed, when the upper arm movement rotates the scapula, the lateral edge of the scapula will lose its force against the chest, and the inner edge of the scapula will appear deformed backward, forming a medial winged scapula; if the rhomboid or rhomboid muscle is paralyzed, when the upper arm movement rotates the scapula, the medial edge of the scapula will lose its force against the chest. The outer edge of the scapula will appear to be deformed backwards, forming a lateral winged scapula. Since the deformed scapula resembles the wings of a cricket, it is clinically named as winged scapula. 1.Anatomical characteristics 1.The anterior serratus muscle is a flat muscle with an extensive starting point, starting from the front of the 1st-9th ribs (the lower 4-5 muscle teeth are inserted between the muscle belly of the external abdominal oblique muscle), and the muscle bundle is submerged along the surface of the thorax under the scapula and moves upward posteriorly, ending at the medial edge of the scapula, with most of the muscle bundle ending at the subscapular angle. The anterior serratus muscle can be divided into three functional components: the upper muscle bundle starts at the 1st and 2nd ribs and ends at the medial superior angle of the scapula, anchoring it to form a rotation center that allows rotation of the scapula when the upper arm is raised overhead; the middle muscle bundle starts at the 3rd-5th ribs and ends at the spinal edge of the scapula, playing the role of pulling the scapula; the lower muscle bundle starts at the 6th-9th ribs and ends at the inferior angle of the scapula, playing the role of pulling the inferior angle to rotate outward and upward. The main function of the anterior serratus is to pull and rotate the scapula, so that the inferior and superior angles of the scapula are rotated inward, while keeping the scapula close to the chest wall, thus optimizing the position of the articular glenoid and maximizing the efficiency of upper limb movement. The anterior serratus is innervated by the long thoracic nerve from the brachial plexus, which consists of anterior branches from the C5, C6, and C7 cervical nerve roots. The branches from C5 and C6 cervical nerve roots are joined by branches of C7 cervical nerve roots to form the long thoracic nerve, which runs deep in the brachial plexus, descends anteriorly and outwardly through the subclavian, above the first rib, and then descends along the chest wall via the nerve sheath to innervate the muscle after the lateral aspect of the anterior serratus muscle, with a total length of up to 24 cm, a long and tortuous journey, so it is easy to be injured. 2, oblique muscle The short tendon of the oblique muscle starts from the upper line of the collar, the external occipital ridge, the collar ligament, the spinous process of all thoracic vertebrae and the supraspinous ligament. Its upper muscle bundle is outwardly downward and ends at the lateral 1/3 of the clavicle, and the middle muscle bundle is horizontally outwardly ending at the acromion. The inferior bundle is directed outward and upward to end at the scapular gland. Because these three muscle bundles are oriented differently, they function differently when contracted. The unilateral rhomboid muscle is triangular in shape, and the combined muscles on both sides make a rhomboid. Its effect on the scapula is that if the three muscle bundles contract simultaneously during spinal fixation, they can pull the scapula toward the spine, and can make the scapula turn the lower angle outward and the upper angle upward along the sagittal axis; if only the upper muscle bundle contracts, it can make the scapula rise; when the lower muscle bundle contracts, it can make the scapula fall. The collateral nerve is the only nerve that innervates the rhomboid muscle, which emanates from the cranial nerve XI and enters the deep surface of the rhomboid muscle vertically through the surface of the posterior cervical triangle to innervate the muscle. 3.Rhomboid muscle The rhomboid muscle is located in the deep layer of the trapezius muscle, between the medial edge of the scapula and the spine, and the muscle fibers travel obliquely from the inner superior to the outer inferior. When the rhomboid muscle and the anterior serratus muscle contract at the same time, one force lifts the scapula in the direction of the spine, and the other force rotates the lateral edge of the scapula downward, the combined force of the two forces points to the chest wall, so that the scapula is tightly attached to the chest wall. The lesser rhomboid muscle starts from the collar ligament and the spinous process of the 7th cervical and 1st thoracic vertebrae and ends at the medial edge of the scapula. The greater rhomboid muscle begins at the spinous process of the 2nd-5th thoracic vertebrae and ends at the spinal edge of the scapula. The greater rhomboid and lesser rhomboid muscles together form the rhomboid muscle, with a very thin layer of foveal tissue between the two muscles. In common clinical injuries to the rhomboid muscle, the greater rhomboid and the lesser rhomboid are often injured at the same time. The rhomboid muscle is innervated by the thoracic dorsal nerve, with most of its nerve fibers coming from the C5 nerve root and a small portion from the C4 and C6 nerve roots. The thoracic dorsal nerve sends fibers to innervate the scapular raphe before crossing the middle trapezius muscle, passing below the brachial plexus nerve to the surface of the rhomboid muscle and innervating the muscle. With proximal fixation, it causes scapular lift, retroversion and inferior gyration. In distal fixation, both sides contract to extend the spine. Etiology Pterygoid shoulder is a shoulder muscle dysfunction, generally due to paralysis and injury of the long thoracic nerve innervating the anterior serratus, the collateral nerve innervating the rhomboid muscle, and the dorsal scapular nerve innervating the rhomboid muscle, causing dysfunction, generally speaking, paralysis of the anterior serratus and rhomboid muscles is more common, and the rhomboid muscle is less common. Etiology includes trauma, inflammation, tumor, and idiopathic. Trauma includes acute pulling or blunt filing injuries (car accident injuries, electric shock injuries, cutting injuries, percussion injuries, etc.); chronic strain injuries (prolonged, heavy load, repeated activities such as carrying, carrying, lifting, pressing, etc.); inflammation (influenza, tonsillitis, polio and other viral infections); tumors (mass compression, tumor invasion); allergic reactions to drugs; poisoning (rust remover, tetanus); and cervical 7 nerve root lesions. There are also some patients with unknown etiology, which is called idiopathic. III. Diagnosis A thorough history is essential for the diagnosis of pterygoid scaphoid. The package history covers the dominant hand, occupation, hobbies, current and previous level of function of the upper extremity, and preference for conservative or surgical treatment. In case of traumatic etiology, the exact mechanism of injury, the site of injury such as neck, shoulder, chest, and axilla, recent illness, and history of vaccination should be elucidated. The clinical presentation often depends on the paralysis of the different muscles or the severity of the nerve affected. The symptoms usually include mild to severe pain in the shoulder and back, shoulder weakness, fatigue and inability to use the upper arm, winging of the scapula and discomfort when raising the arm, or in severe cases, inability to raise the arm above shoulder level, and inability to dress or comb the hair. Soreness and weakness of the affected upper limbs and fatigue at work are its prodromal symptoms. Electromyography may reveal damage to the long thoracic nerve, paramedian nerve and thoracodorsal nerve. 1. Anterior serratus palsy The typical patient with anterior serratus palsy will have pain around the shoulder (usually on the right side), which either arises spontaneously or is associated with some traumatic event. The pain may also radiate down to the arm and scapula. In addition, the patient usually complains of shoulder weakness, and the athlete may complain of decreased performance. When severe pain is present, a neuritis should be suspected. The classic or medial scapular pterygoid shoulder at rest, when the patient is asked to flex forward, arms horizontal and or push against a wall, the protruding scapular pterygoid may not be obvious. 2. Trapezius paresis Typical manifestations include stiffness, pain, and weakness of the scapular girdle, especially when raised overhead and after prolonged exertion. Patients often complain of dull pain and heaviness in the shoulder, as if a brick were pressing down on it. The patient is significantly limited in all activities above the head. Examination reveals an asymmetrical collar and drooping of the affected shoulder. When the arm is raised on the side of the body, the scapula moves to the opposite side to form a wing, and when the scapula is pressed by hand, the patient feels comfortable when raising the arm. When the patient is allowed to push the wall with both hands for support, the medial edge of the scapula is seen to buckle and a wing-like deformity occurs. 3. Rhomboid palsy Typically, the patient will experience pain along the medial side of the scapula, sometimes radiating to the C5 and C6 dermatomes of the arm. When raising the arm, the patient may feel abnormal movement or pulling of the shoulder. In addition, neck pain is often aggravated by changes in weather and insomnia is often due to shoulder discomfort. Rhomboid palsy produces a very subtle pterygoid scapula in which the scapula translates laterally and the inferior scapular angle rotates laterally. Because the anatomical location of the rhomboid muscle is located on the deep side of the trapezius muscle and the winged scapula is not obvious, it is difficult to diagnose rhomboid palsy. IV. Treatment 1. Non-surgical treatment Most patients with pterygoid scapula caused by blunt trauma or unknown causes can usually recover within 1 year. If the anterior serratus, trapezius or rhomboid function is not restored after 1 year then surgical treatment is required. Conservative treatment includes avoiding any activity that may re-injure or strain the recovering nerve, and exercising the muscles around the scapular band. 2.Surgical treatment If the course of the disease is longer than 1 year and conservative treatment is not effective, the patient still has pain and affects the working life, surgical treatment is feasible. Mainly take the tendon transposition surgery, serious cases feasible scapular chest wall fusion. V. Prevention Change some bad working and living habits as early as possible, backpack should not be too heavy, and backpack straps should not be too tight and too thin, so as not to damage the long thoracic nerve, paracentral nerve and thoracodorsal nerve by excessive local pressure on the shoulder. In work and life, it is important to have proper rest and to combine work and rest in order to release the local compression and facilitate the recovery of nerve function. Enhance muscle strength training to cushion the compression of nerves by pathogenic factors, and at the same time, delay the process of muscle atrophy.