What is the most common cause of tendonitis and bursitis?

• A. Acute Traumatic Injury
• B. Repetitive Overuse With Minor Injury
• C. Bacterial Infection
• D. Autoimmune Disease

Answer: (B)

Repetitive overuse with minor injury is the usual culprit because tendonitis and bursitis typically arise from chronic mechanical irritation rather than a single event. Repeated movements—lifting, throwing, typing, overhead activities—cause microtrauma to tendon fibers and the nearby bursa. The tissues respond with inflammation, leading to pain, swelling, and decreased function. If the activity continues, these microtears accumulate and inflammation can become chronic. In contrast, an acute traumatic injury is a one-time event, septic infection is relatively rare and usually with systemic signs, and autoimmune diseases can involve these structures but are less common causes overall. So the pattern of ongoing, repetitive use best explains why tendonitis and bursitis are most frequently seen.