1、Patients often have diffuse dull pain in the periscapular area, located in the posterior lateral part of the shoulder, which can radiate to the back of the neck and the arm, but the radiation pain is often located in the posterior side of the upper arm. Patients often feel weakness in shoulder abduction and external rotation. Progressive cases may have atrophy of the supraspinatus muscle, but in most cases, there is no obvious muscle atrophy, making clinical diagnosis more difficult.
2、Patients often have a history of trauma or overuse, such as direct trauma or indirect injury to the shoulder, such as overextension of the shoulder joint when reaching out during a fall, resulting in sprain; some patients also have a history of overuse of the shoulder joint, such as sports-related overuse (such as volleyball, basketball, tennis, etc.), and a history of shoulder work-related injury.
3、Patients with trauma or overuse usually have sharp pain in the shoulder, which may worsen during shoulder movement. The pain may be persistent, and severe cases may affect sleep. There is no obvious muscle atrophy, difficulty in lifting the arm, or the affected hand cannot reach the opposite shoulder. Some patients have shoulder pain but no other symptoms, and the pain may last for several years.
4、Pain at the suprascapular notch or at the pain point between the clavicle and the scapular spine triangle is the most common sign of suprascapular nerve entrapment. The trapezius area may also have tenderness. If there is entrapment at the scapular notch, the pain point is at the scapular notch, shoulder abduction, and external rotation muscle weakness; atrophy of the supraspinatus and infraspinatus muscles, especially atrophy of the infraspinatus muscle. Due to the innervation of the scapular joint branch to the acromioclavicular joint, there may be pain at the acromioclavicular joint, such as at the acromial fossa notch, the pain is less than that at the suprascapular notch, the pain point is at the acromial fossa notch, and the local manifestation is not obvious except for atrophy of the infraspinatus muscle.