Bursitis is often confused with arthritis because both conditions cause pain, swelling, and stiffness around joints. Although they share similar symptoms, they are distinct medical conditions affecting different anatomical structures. Understanding this difference is essential for accurate diagnosis and effective treatment, as bursitis involves soft tissues outside the joint, while arthritis is a pathology of the joint capsule and its components.
Defining Bursitis and Arthritis
Bursitis is the inflammation of a bursa, which are small, fluid-filled sacs positioned throughout the body near joints. These sacs act as cushions, reducing friction between bones, tendons, muscles, and skin. Bursitis commonly affects larger, active joints, such as the shoulder, elbow, hip, and knee. The inflammation causes the bursa to swell with excessive fluid, leading to localized pain and tenderness.
In contrast, arthritis is a comprehensive term for over 100 different diseases involving inflammation and degeneration of the joint itself. A joint is the meeting point of two or more bones, encased by a capsule and lined with a synovial membrane. The two most common forms are osteoarthritis, involving the breakdown of joint cartilage, and rheumatoid arthritis, an autoimmune disorder attacking the synovial lining. Arthritis directly affects internal joint structures, often leading to progressive damage to cartilage and bone.
The Critical Distinction
Bursitis is not a type of arthritis because the inflammation occurs in different anatomical locations. Bursitis is classified as a periarticular condition, meaning it affects the soft tissues surrounding a joint. The bursa sacs are situated outside the main joint capsule, serving as external friction-reducing protectors. This means bursitis does not involve the joint’s internal mechanism, such as the cartilage or synovial membrane.
Arthritis is an intra-articular condition, affecting the joint’s interior structures. The pathology of arthritis targets the joint lining, cartilage, and bone ends, which are the main components enabling joint movement. Bursitis is typically an acute issue, often caused by overuse or trauma, that resolves within a few weeks with appropriate treatment. Arthritis, however, is generally a chronic and progressive disease that can result in long-term joint destruction.
Shared Symptoms and Common Treatments
The confusion between bursitis and arthritis stems from shared symptoms like localized pain, swelling, and stiffness near a joint. Both conditions can restrict the range of motion, making everyday activities difficult. Bursitis pain is often more superficial and tender directly over the inflamed bursa. Arthritis pain tends to be a deeper, achy discomfort originating from within the joint.
Diagnosis relies on a physical examination and imaging to visualize the affected structures. An ultrasound or MRI is often used to differentiate between an inflamed bursa and internal joint damage. Initial management of both conditions shares common goals: reducing inflammation and alleviating pain.
Standard non-surgical treatments include rest, applying ice, and using nonsteroidal anti-inflammatory drugs (NSAIDs). Physical therapy is also a shared strategy, focusing on strengthening surrounding muscles and restoring mobility. For persistent inflammation, a healthcare provider may administer a corticosteroid injection, specific to the diagnosis—either into the bursa for bursitis or into the joint space for arthritis.