The clavicle, commonly known as the collarbone, is a long, slender bone that extends horizontally across the upper chest. It serves as the only bony attachment between the arm and the main torso skeleton. This structure connects the sternum (breastbone) to the scapula (shoulder blade), forming two distinct joints: the sternoclavicular (SC) joint at the center and the acromioclavicular (AC) joint at the shoulder. The clavicle acts as a strut, holding the shoulder out and away from the body to allow for a full range of arm motion. Due to its exposed position and function in transferring force, the clavicle is vulnerable to injury, making pain in this area a common concern.
Acute Injuries and Fractures
Sudden, intense collarbone pain most often results from a traumatic event that causes acute damage to the bone or its supporting ligaments. Clavicle fractures are among the most frequent bone breaks, accounting for 5% to 10% of all adult fractures. These breaks typically occur when a person falls directly onto the shoulder or lands on an outstretched hand, transmitting significant force up the arm.
The majority of clavicle fractures, approximately 80%, happen in the mid-shaft, the narrowest and weakest part of the bone. An individual with a fracture will experience immediate, sharp pain that worsens with any attempt to move the arm or shoulder. Visible signs often include swelling, bruising, and sometimes a noticeable bump or deformity at the fracture site, along with a grinding sensation when the shoulder is moved.
Pain can also stem from a sprain or separation of the acromioclavicular (AC) joint, where the collarbone meets the highest point of the shoulder blade. This injury is caused by tearing the ligaments that stabilize the joint, usually from a fall directly onto the shoulder. AC joint injuries are graded based on the severity of the ligament damage, which dictates the level of pain and the degree to which the clavicle end is displaced upward.
Less commonly, the sternoclavicular (SC) joint, located closer to the center of the chest, can be injured or dislocated. While rare, SC joint injuries can result from severe trauma, and symptoms include pain and swelling near the sternum, sometimes making it difficult to breathe deeply.
Chronic Joint and Soft Tissue Issues
When collarbone pain develops gradually rather than suddenly, it is often related to cumulative stress, degenerative changes, or soft tissue problems. Arthritis is a frequent cause of chronic joint pain, most commonly affecting the AC joint due to years of wear and tear (osteoarthritis). This degeneration of the joint cartilage can be accelerated by repetitive overhead activities or heavy weightlifting, sometimes leading to distal clavicle osteolysis, or “weightlifter’s shoulder.”
Inflammatory conditions, such as rheumatoid arthritis, can also affect the clavicular joints, causing pain, stiffness, and swelling that often presents symmetrically in both collarbones. Beyond the joints, the soft tissues surrounding the clavicle, including muscles and ligaments, can become strained from overuse or improper mechanics. Repetitive motions in sports or work can lead to chronic microtrauma, causing a persistent ache that worsens with activity.
Postural issues significantly contribute to chronic collarbone discomfort by placing continuous, uneven stress on the shoulder girdle. A slumped or forward-head posture can alter the alignment of the scapula and clavicle, leading to muscle fatigue and a dull, nagging pain. This mechanical imbalance can also be a factor in the development of Thoracic Outlet Syndrome (TOS), a condition where the space between the clavicle and the first rib, called the thoracic outlet, becomes narrowed.
In TOS, the compression of nerves and blood vessels passing through this narrow space can result in pain above the collarbone that often radiates into the arm and hand. Symptoms of nerve compression may include numbness, tingling, or weakness in the arm. Compression of blood vessels can cause swelling or a change in the color of the hand. Identifying this type of referred pain is important, as the source is not the clavicle itself but the structures passing beneath it.
When to Seek Medical Attention
While many minor causes of collarbone pain can resolve with rest and conservative care, certain symptoms require immediate professional medical evaluation. Any severe pain resulting from a fall or direct injury warrants an urgent visit to rule out a fracture or serious joint separation.
You should seek medical care promptly if you notice signs of structural damage, such as a visible deformity, a lump near the collarbone, or a shoulder that appears sagging or drooping. Also seek care if you experience symptoms suggesting nerve or vascular compromise, including numbness, tingling, or weakness that extends down the arm and into the fingers. Furthermore, symptoms that may indicate a more systemic issue, such as a fever, chills, or warmth and pus draining from the skin near the collarbone, could signal a bone infection (osteomyelitis).
It is particularly important to seek emergency care if collarbone pain is accompanied by difficulty breathing, chest tightness, or severe abdominal pain, as these symptoms can indicate injury to underlying organs or a life-threatening medical event. Even chronic pain that persists for more than a few weeks despite at-home care should be evaluated to identify the underlying issue.