Shoulder arthritis is a condition where the smooth cartilage covering the ends of the bones within the shoulder joint begins to wear away. This protective tissue allows the bones to glide smoothly. When this cartilage deteriorates, it can lead to increased friction and changes within the joint, resulting in discomfort and reduced movement.
Recognizing the Symptoms
A primary symptom of shoulder arthritis is persistent pain, which can manifest as a dull ache, sharp sensation, or deep throbbing within the joint. This pain often worsens with activity or after periods of rest. Individuals may also experience stiffness, making it difficult to lift the arm or perform everyday tasks, especially after inactivity.
Another common indicator is a grinding, clicking, or popping sensation when moving the shoulder. This occurs as roughened bone surfaces rub against each other due to cartilage loss. Over time, the range of motion in the affected shoulder decreases, making it harder to reach overhead or behind the back.
Visual and Physical Manifestations
Shoulder arthritis can also present with observable physical changes around the joint. Swelling may become apparent. The area might also feel tender to the touch, particularly when pressure is applied directly over the joint line. In more advanced stages, the shoulder’s contour may visibly change due to the formation of bone spurs or a narrowing of the joint space.
During a physical examination, a doctor might notice a restricted active and passive range of motion, meaning the individual cannot move their arm fully on their own, and the doctor also cannot move it fully for them. Muscle weakness around the shoulder can also be present. Tenderness can be localized to specific areas, which helps pinpoint the affected structures within the shoulder joint.
Common Types Affecting the Shoulder
Several types of arthritis can affect the shoulder, each with distinct underlying causes. Osteoarthritis, often called “wear-and-tear” arthritis, is the most common type and results from the gradual breakdown of cartilage over time, frequently due to aging or prior injury. Rheumatoid arthritis is an autoimmune disease where the body’s immune system mistakenly attacks the joint lining, leading to inflammation and cartilage destruction. Post-traumatic arthritis develops after a specific injury, such as a fracture or dislocation, where the damage to the joint surfaces can accelerate cartilage degeneration.
How Doctors Confirm the Diagnosis
Medical professionals typically confirm a diagnosis of shoulder arthritis through a combination of a thorough physical examination and imaging tests. During the physical exam, a doctor will assess the shoulder’s range of motion, identify areas of tenderness, and evaluate muscle strength. They may also perform specific maneuvers to reproduce pain and assess joint stability. This hands-on assessment provides important clues about the extent of joint involvement.
X-rays are the primary imaging tool used to visualize the shoulder joint and are typically the first step in diagnosis. These images can reveal characteristic signs of arthritis, such as narrowing of the joint space, the presence of bone spurs (osteophytes), and changes in the bone density beneath the cartilage, known as subchondral sclerosis. While X-rays are usually sufficient, magnetic resonance imaging (MRI) or computed tomography (CT) scans may be used for a more detailed assessment of soft tissues or complex bony changes, especially if surgery is being considered. These advanced imaging techniques provide a more comprehensive view of the joint’s internal structures.