Why Does My Deltoid Hurt? Common Causes and Symptoms

Deltoid pain is common, causing discomfort in the shoulder. This pain can range from a dull ache to a sharp, sudden sensation.

The Deltoid Muscle

The deltoid muscle is a large, triangular-shaped muscle that forms the rounded contour of the shoulder. It covers the shoulder joint, which is a ball-and-socket joint connecting the arm to the torso.

The deltoid is comprised of three parts: the anterior (front), lateral (side), and posterior (rear) heads. The anterior deltoid assists in moving the arm forward, the lateral deltoid is responsible for lifting the arm away from the body, and the posterior deltoid helps move the arm backward. These segments enable a wide range of arm motion.

Common Reasons for Deltoid Pain

Deltoid pain often results from overuse, injury, or underlying shoulder conditions. Its constant involvement in arm movements makes it prone to irritation and strain.

Muscle Strain or Tear

A common cause of deltoid pain is a muscle strain, which occurs when the muscle fibers are overstretched or torn. This can result from sudden heavy lifting, an accident, or repetitive activities.

Rotator Cuff Issues

Problems with the rotator cuff, a group of muscles and tendons that stabilize the shoulder, can cause deltoid pain. Inflammation of these tendons (tendinitis) or tears leads to pain and tenderness in the front or side of the shoulder. These issues often stem from overuse or aging.

Bursitis

Bursitis involves the inflammation of a bursa, a small, fluid-filled sac that reduces friction between tissues. In the shoulder, bursae cushion areas between bones and tendons. When these bursae become irritated, often due to injury or overuse, they can swell and cause pain in the deltoid area. This pain can be a dull ache or a sharp, pinching sensation with arm movement.

Shoulder Impingement

Shoulder impingement occurs when tendons or bursae in the shoulder are compressed as the arm moves, leading to pain. This often happens when the space between the top of the shoulder blade (acromion) and the rotator cuff tendons narrows. Repetitive overhead movements can contribute to this condition. The pain from impingement is often felt in the front and side of the deltoid muscle.

Referred Pain

Pain felt in the deltoid area can sometimes originate from other parts of the body, a phenomenon known as referred pain. For instance, issues with nerves in the neck can cause sensations like pins and needles or burning pain that radiate down to the shoulder and arm.

Identifying Specific Symptoms

Specific characteristics of deltoid pain can help identify its source.

A sharp, sudden pain often suggests an acute injury, such as a muscle strain or tear, particularly if it occurs after a specific incident. In contrast, a dull, aching pain might indicate inflammation or overuse, common with conditions like tendinitis or bursitis. This type of pain can worsen with activity and may persist even at rest.

Pain that intensifies with specific movements, such as lifting the arm overhead or reaching behind the back, can point towards impingement or rotator cuff issues. Night pain, especially when lying on the affected shoulder, is common with bursitis and rotator cuff problems. The presence of weakness in the arm, difficulty moving the shoulder, or a reduced range of motion suggests a significant issue impacting the shoulder’s function. Clicking, grinding, or popping sounds during arm movement can indicate structural issues within the joint.

When to Consult a Professional

While many instances of deltoid pain can resolve with rest and self-care, certain symptoms warrant professional medical attention.

Consult a healthcare provider if the pain is severe and does not improve with rest, ice, or over-the-counter pain relievers after a few weeks. Immediate medical attention is advisable for sudden, acute pain following an injury, particularly if accompanied by an inability to move the arm or shoulder. Other concerning signs include a noticeable deformity around the shoulder joint, persistent swelling or bruising, or pain accompanied by numbness, tingling, or weakness in the arm or hand. Additionally, if the pain worsens progressively, disrupts sleep, or is accompanied by signs of infection like redness, warmth, or fever, professional assessment is important.