An osteophyte, commonly known as a bone spur, is an excess bony growth that develops along the edges of bones, typically near joints. This bony projection is the body’s attempt to stabilize a joint experiencing wear, tear, or instability. Bone spurs are common in the shoulder joint. A significant percentage of people over the age of 60 show signs of these growths on imaging, even if they do not cause symptoms.
Mechanisms of Bone Spur Formation
The formation of bone spurs in the shoulder is a biological response to stress or degeneration, essentially an overcompensation by the body’s repair systems. One primary mechanism involves degenerative changes within the main shoulder joint, known as the glenohumeral joint. When the smooth cartilage that cushions the ends of the humerus (upper arm bone) and the glenoid socket wears away due to osteoarthritis, the body attempts to compensate for the instability.
This degradation of joint surfaces triggers the formation of new bone at the joint margins, resulting in spurs that restrict the smooth gliding motion of the ball-and-socket joint. These osteophytes often lead to stiffness and a reduced range of motion as the bony growths mechanically block movement.
The second major cause involves chronic irritation of the rotator cuff tendons, often leading to shoulder impingement syndrome. In this scenario, bone spurs commonly develop on the undersurface of the acromion, the bony roof of the shoulder blade. The presence of an acromial spur narrows the subacromial space, which houses the rotator cuff tendons and the bursa.
As the arm is raised, particularly in overhead activities, this acromial spur pinches or rubs against the underlying tendons, leading to inflammation and pain. The resulting spur then exacerbates the impingement. Therefore, the location of the spur—either on the main joint surfaces or the acromion—often indicates the underlying pathological process.
Symptoms and Medical Confirmation
The presence of a bone spur does not automatically guarantee symptoms, but they become noticeable when they enlarge or impinge on soft tissue. The most common symptom is pain, varying from a dull ache deep within the joint to a sharp, catching pain when the arm moves. Pain is frequently felt when reaching overhead or behind the back. This is often accompanied by progressive restriction in range of motion and stiffness. If the spur compresses a nerve or causes significant rotator cuff damage, patients may also experience weakness, numbness, or tingling.
Medical confirmation begins with a thorough physical examination to assess pain levels, range of motion, and specific movements that provoke symptoms. The physician performs tests to determine if the pain originates from the main joint or from tendon impingement. Visualization is necessary to confirm the diagnosis and rule out other causes of shoulder pain. The primary diagnostic tool for visualizing bone spurs is a standard X-ray, which allows the physician to determine their size, shape, and exact location.
While X-rays confirm the presence of the spur, they do not show soft tissue. Therefore, a magnetic resonance imaging (MRI) scan may be ordered if there is suspicion of soft tissue damage, such as a rotator cuff tendon tear, which often occurs alongside an irritating bone spur.
Treatment Pathways
The management of shoulder bone spurs is tailored to the severity of the symptoms and the underlying cause, prioritizing non-surgical conservative treatments first. Initial management focuses on reducing inflammation and pain with nonsteroidal anti-inflammatory drugs (NSAIDs). Rest and activity modification are also recommended to avoid movements that irritate the spur and surrounding soft tissues. If oral medication is insufficient, a physician may recommend a corticosteroid injection directly into the joint or the subacromial space for a powerful anti-inflammatory effect.
The core component of conservative care is physical therapy (PT), which aims to restore strength and flexibility to the shoulder. A specialized PT program works to improve the mechanics of the shoulder and strengthen the rotator cuff muscles, often creating more space for the tendons to move and alleviating impingement symptoms.
Surgical intervention becomes an option when conservative treatments fail to provide lasting relief, or when the bone spur is causing severe impingement or a significant rotator cuff tear. The goal of surgery is to remove the obstruction and create more space for the tendons. This procedure is most often performed arthroscopically, using small incisions and a camera. For spurs causing impingement, the surgery may involve an acromioplasty, where the spur on the acromion is shaved down to decompress the subacromial space. Recovery from arthroscopic spur removal is generally swift, with most patients requiring a period of physical rehabilitation to fully regain strength and function.