According to the American Academy of Orthopaedic Surgeons, these are the common causes of hip bursitis:

• Overuse of the hip, often from activities such as biking, running, climbing stairs or standing up for long periods
• Having an injury to the hip, such as from a fall, bump or too much pressure
• Having had surgery on the hip
• Having calcium deposits or bone spurs
• Having diseases of the spine, including arthritis or scoliosis
• Having one leg that's shorter than the other
• Having rheumatoid arthritis