Shoulder pain when reaching out (abduction or flexion) is a common complaint. This symptom suggests that the mechanical action of moving the arm is irritating structures within the joint space. The shoulder is a highly mobile ball-and-socket joint, composed of the humerus, scapula, and clavicle, relying heavily on soft tissues for stability. This complexity makes the area susceptible to wear or inflammation during dynamic movement.
Specific Conditions That Cause Pain When Reaching
The discomfort felt when reaching is frequently caused by a reduction of space beneath the acromion, the bony arch at the top of the shoulder blade. This narrow area, known as the subacromial space, is where soft tissues pass and can become compressed during movement. The three most frequent diagnoses associated with this pain mechanism are shoulder impingement syndrome, rotator cuff tendinitis, and subacromial bursitis.
Shoulder impingement occurs when the rotator cuff tendons or the bursa are pinched as the arm is lifted. Raising the arm causes the head of the humerus to move up, mechanically reducing the subacromial space. This pinching generates a sharp, localized pain, often worst when the arm is lifted to shoulder height.
Rotator cuff tendinitis involves inflammation of the four tendons that stabilize the shoulder joint. When these tendons are swollen, reaching puts pressure on the inflamed tissue against the overlying bone. This compression during abduction or flexion causes characteristic pain that limits the range of motion.
Subacromial bursitis is inflammation of the bursa, a fluid-filled sac that cushions the rotator cuff tendons and the acromion bone. When the bursa swells, it takes up more space in the subacromial area. Reaching out then squeezes the swollen bursa, resulting in sudden, intense pain that feels like a deep pinch. These conditions often coexist, as irritation of one structure can lead to the inflammation of neighboring tissues.
Immediate Steps for Relief and Activity Modification
Initial management involves modifying activities to allow irritated structures to settle down. Avoid movements that provoke pain, especially repetitive overhead lifting or carrying heavy objects with the affected arm. Focus on “active rest” where the arm is used below shoulder height for light, pain-free tasks, preventing stiffness that can result from complete immobilization.
Applying cold therapy helps reduce localized inflammation. An ice pack, wrapped in a thin towel, should be applied to the painful area for about 15 minutes, two to three times a day. Over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, may also be taken temporarily to manage pain and swelling.
Changing your sleeping position is an effective way to relieve night pain and prevent further irritation. Avoid sleeping directly on the painful shoulder, as this compresses the joint structures. Instead, sleep on your back with a small pillow placed under the arm and elbow to keep the shoulder slightly elevated and in a neutral position.
A gentle exercise known as the pendulum or Codman’s exercise can help maintain joint mobility without actively engaging the painful muscles. To perform this, lean over and support your body with the good arm, allowing the affected arm to hang straight down. Use your body’s momentum to create small, passive swings in a circular motion, keeping the shoulder muscles relaxed. This gravity-assisted movement helps create temporary space within the joint capsule.
Knowing When to Seek Professional Diagnosis
While many cases of shoulder pain resolve with home care, certain indicators suggest the need for a consultation with a healthcare provider. If the pain persists for longer than one or two weeks despite consistent rest, ice, and over-the-counter medication, professional evaluation is warranted. Continued discomfort may suggest a more significant underlying issue requiring targeted treatment.
A sudden loss of strength, or the inability to lift the arm away from the body, is a red flag that could indicate a complete rotator cuff tear. Severe pain that wakes you up consistently at night, or pain radiating down the arm past the elbow, also suggests serious irritation. Any sign of acute trauma, such as a fall, or visible deformity of the shoulder joint, requires urgent medical attention.
Consulting a physician or physical therapist allows for a definitive diagnosis, often involving a physical examination to test muscle strength and range of motion. This assessment helps determine if imaging tests, such as X-rays or an MRI, are necessary to visualize the soft tissues and bone. A professional diagnosis is the first step toward a structured treatment plan, which may include formal physical therapy.