In Subacromial Impingement Syndrome, which is one of the most common shoulder problems, patients mostly complain of pain localized on the anterior aspect of the shoulder and exacerbated by elevation of the arm (1,2).
The area formed by the humeral head in the lower part, the acromion in the upper part, the acromioclavicular joint and the coracoacromialligament is called the Subacromial Space. It is approximately 7-12 mm in size (3). The tendons of the rotator cuff muscles, which stabilize the glenohumeral joint, pass through this gap.
Subacromial Impingement Syndrome was defined by Neer in 1972 as “compression of the biceps tendon, rotator cuff muscles and subacromial bursa, especially in the subacromial region during shoulder elevation” (4). Mechanical and vascular problems lie in the pathophysiology of this syndrome, which is mostly seen in the 50s. Workers who constantly use their arms in overhead positions, carpenters, and people who do sports related to swimming and throwing are included in the high-risk group with narrowing of the subacromial space (3,5).
Subacromial Impingement Syndrome is characterized by pain and loss of function. Pain increases with rest at night and causes movement limitations in the upper extremity, resulting in functional loss in activities of daily living (2,3). The pain seen in subacromial impingement syndrome can also cause sleep problems (6).
FACTORS CAUSED BY SUBACROMIAL IMPACT SYNDROME
We can divide the factors causing SPS into 2 as intrinsic and extrinsic factors. Intrinsic factors are directly related to the subacromial space. Secondary thickening of the coracoacromialligament, which forms the upper part of the subacromial space, due to repetitive activities directly causes narrowing of the subacromial region. Degenerative changes in the acromioclavicular joint and new bone formation are also among the intrinsic factors. Extrinsic factors: Postural changes, glenohumeral joint instability, rotator cuff and scapulothoracic muscle imbalance, posteriorcapsular tension, and repetitive use of the arm in overhead activities (3).
Disorders in the glenohumeral region muscles are one of the factors that cause subacromial impingement syndrome. The rotator cuff muscles (Supraspinatus, teres minor, infraspinatus, subscapularis) play a major role in the stabilization of the humeral head during the elevation of the shoulder, the weaknesses in these muscles cause the formation of SPS. The weak rotator cuff cannot resist the upward pulling force of the deltoid and causes superior translation to occur at the head of the humerus. The loads that occur during activities in which the arm is used in continuous elevation cause degenerative changes in the supraspinatus tendon. Postural problems such as rounded shoulders and anterior tilt of the head are among the factors that cause subacromial impingement syndrome. There is tension in the pectoralis minor muscle with increasing thoracickyphosis in posture. Tension of the pectoralis minor muscle causes increased protraction of the scapula and internal rotation of the glenohumeral joint, resulting in narrowing of the subacromial space. Posterior capsule tension causes superior and anterior translation of the humeral head, causing mechanical compression of the structures passing through the subacromial space with increasing pressure on the anterior surface of the acromion (3).
Scapular dyskinesia is defined as abnormal scapular movement during elevation of the shoulder. Trapezius and Serratusanterior are 2 muscles that play a major role in stabilizing the scapula. Disorders in these muscles cause scapular dyskinesia and cause deterioration in the movements of the scapula. Kibler has gathered scapular dyskinesia under four headings. The first three types of scapular movements are considered abnormal, and the fourth type is normal movement:
• Type I: Inferior angle prominence (increased anterior tilt)
• Type II: Medial edge prominence (increased internal rotation)
• Type III: Superior edge prominence (increased downward rotation)
• Type IV: Symmetrical scapulohumeral rhythm
Changes in the activation of the muscles in the scapulothoracic region and decrease in soft tissue flexibility cause the scapular kinematics to be affected. In individuals with subacromial impingement syndrome, decreased activation of the serratus anterior and middle and lower parts of the trapezius muscle; It was observed that there was an increase in the upper part activation. Tension in the pectoralis minor causes internal rotation of the scapula. For this reason, the treatment approaches used in the treatment of subacromial impingement syndrome have started to be scapula-centered approaches (3).
SYMPTOMS AND CLASSIFICATION OF SUBACROMIAL IMPACT SYNDROME
STAGE 1: It is present with edema and hemorrhage. Patients under the age of 25 usually have a history of repeated trauma with overhead activity or sports. Symptoms are mostly reversible (3). There is a blunt pain around the shoulder that can progress laterally. Tenderness is detected on palpation on the anterior surface of the tuberculum majus and acromion. Rest and conservative treatment is applied (2).
STAGE 2: Fibrosis and tendinitis are seen in the tendon and bursa. It is mostly present in patients between the ages of 25-40 (3). More severe sensitivity is detected compared to stage 1. Conservative treatment is applied, if no response is obtained, surgical treatment is started (2).
STAGE 3: It is characterized by changes in bone tissue and tears in tendons. Patients are mostly over the age of 40 (3). In this phase, there is weakness as well as pain. Weakness in abduction and external rotation is evident. In chronic cases, atrophy can also be seen. Treatment is usually surgery (2).
The symptoms are as follows:
• Crepitus in the tendon
• Muscle weakness
• Loss of movement
• Painful arc varying between 60/70–120° in shoulder elevation
• Excessive scapular mobility
• Functional loss
• Inability in movements (2)
METHODS OF EVALUATION OF SUBACROMIAL IMPACT SYNDROME
Hawkins Test: The patient flexes the arm to 90 degrees and in this position the arm is forced into internal rotation. With this maneuver, the greater tuberculum is pushed under the coracoacromial arch and causes pain in patients with CNS (4,5).
Neer Test: The scapula is stabilized and the patient’s arm is passively forced into flexion. The tuberculum majus is pushed towards the coracoacromial posterior. This test causes pain in patients with CNS (5).
Supraspinatus (Jobe) Test: While holding the patient’s arm in 90 degrees of flexion and internal rotation in the scapular plane, downward resistance is applied. If pain occurs, the patient cannot resist resistance (5).
Painful Arc Test: Pain between 60° and 120° in shoulder abduction indicates that the test is positive (2) .
Zero Degree Abduction Test: While the arms are at 0 degrees abduction, abduction is requested against resistance. If there is weakness in the supraspinatus muscle, the patient cannot resist the resistance (2).
Drop Arm Test: The patient abducts his arm 90 degrees and is asked to lower it slowly. The test is positive if the patient cannot perform this movement or if the arm falls painfully (2).
Fear and Reduction Test: The patient lies in the supine position, the shoulder is brought into 90 degrees abduction and 90 degrees external rotation. If the patient begins to subluxate anteriorly, the test is positive if fear occurs (7).
TREATMENT IN SUBACROMIAL IMPACT SYNDROME
One of the primary goals in treatment is to reduce pain. Increasing joint movements is the second goal of the physiotherapy program. However , the source of the limitation of movement needs to be analyzed very well . Since there will be a limitation of motion due to pain in subacromial impingement syndrome, reducing pain will automatically increase joint motion (1,3,4).
Patient education is an important step in starting the rehabilitation program . This is one of the important components that affect the patient’s motivation in rehabilitation. Patient education should include general information and the content of the exercise program and the necessary steps to make it right (9).
Conservative treatment; prevention, medical treatment, physical therapy and exercises (8). For prevention, movements that may cause compression of the rotator cuff and subacromial bursa should be avoided in daily life. Activities of daily living are regulated and it is tried to prevent people from doing overhead activities (8).
NSAIDs are involved in controlling pain and inflammation (8).
Cold application is applied in the acute period when the complaints are very severe. Applying ice for 10-20 minutes following activities and exercises that cause symptoms reduces the risk of inflammation later on. Cold ; raising the pain threshold, slowing down the nerve conduction velocity, and the gate-control theory have a pain-relieving effect (8).
Superficial heat application: It is used to benefit from muscle relaxation and analgesic effects before exercises in subacute and chronic periods. Agents such as hot-pack and infrared can be used. As a result of local heat application, vasodilation occurs, metabolism accelerates, connective tissue viscoelasticity increases, muscle spasm is resolved and pain decreases (8).
Electrotherapy: It is tried to benefit from the analgesic effects of TENS and diadynamic currents (8). TENS; According to the gate control theory, it stimulates the sensory A fibers with high frequency stimulation, and the impulses of this stimulus occupy the path to the brain and do not allow the passage of pain (5).
Ultrasound: It is the best physical therapy agent with deep heating. Ultrasound increases circulation with vasodilation and removes metabolic wastes that stimulate pain. It can also increase the extensibility of tendons. It is applied at a dose of 1.2-1.5w/cm2 for 8 minutes for the supraspinatus tendon ( 5,8).
Exercise: The main complaint of the patient in subacromial impingement syndrome is pain, so the exercises given should not cause pain in the patient. During the treatment, the patient should be well observed and exercises should be done considering his adequacy (3).
1) Shoulder posterior capsule stretching exercise: Starting from 90° shoulder flexion, the side stretched in the horizontal plane in the direction of adduction is to be held by paying attention to the straightness of the elbow (4).
2) Shoulder inferior capsule stretching exercise: The patient positions his shoulder in 180° flexion, with the elbow fully flexed and behind the head of the forearm, and tries to pull it towards the healthy side by holding the elbow on the stretched side with the hand of the healthy side (4).
3) Anterior capsule stretching exercise: The patient puts his arm in contact with the wall while standing. He is asked to turn his body in the opposite direction of the wall and is asked to stop when he feels tension in the anterior region of the shoulder (4).
4) Pectoral Stretch: The patient stands 3 steps behind a wall. He is asked to place both elbows on the wall at shoulder level. It is desired to stretch the chest muscles and feel the tension by reaching forward with the body weight (4).