A bursa is a small fluid-filled sac that sits near a bone.
It cushions and protects nearby tissues when they rub against or slide over
bones. Bursitis happens when a bursa gets irritated and swollen. In the case of
trochanteric bursitis, bursitis occurs due to an exaggerated movement of the
gluteus medius tendon over the outer femur.
Inflammation of trochanteric bursa is one of the most common
causes of hip pain. The normally paper-thin bursal wall thickens and loses its lubrication,
resulting in outer thigh pain. Most of the cases of trochanteric bursitis are
caused by an abnormal gait due to various conditions, such as knee arthritis,
ankle sprains, leg length discrepancy, back pain and others.