Tendon Disorders: Trochanteric Bursitis
Normal Anatomy
The hip joint functions as one of the most important joints in the human body. Designed for both mobility and stability, the hip allows the entire lower extremity to move in three planes of motion, while providing an important shock absorption function to the torso and upper body. The hip is a ball and socket joint, uniting the femur (thigh bone) with the pelvis. As a result of this configuration, the leg moves forwards and backwards, side to side, and rotates to the right and left.
The pelvis features two cup-shaped depressions called the acetabulum, one on either side of the body. The femur, or thigh bone, is the longest bone in the body and connects to the pelvis at the hip joint. The head of the femur, shaped like a ball, fits tightly into the acetabulum, forming the ball and socket joint of the hip.
Embedded within the acetabulum of the pelvis lies an important structure known as articular cartilage; this cartilage has two very important functions. First, the smooth, low friction surface of the cartilage allows the hip joint to move freely in all planes of movement. Second, the articular cartilage cushions the hip during weight bearing activities, providing an important shock absorption function to the entire lower extremity.
The hip joint also features a complex system of ligaments that provide stability for the pelvis and lower extremity. The ligaments of the hip joint connect the femur to the pelvis and are essential to keeping the hip from moving outside of its normal planes of movement.
The muscles of the hip joint have dual responsibilities. They provide the dynamic functions necessary to raise and lower the lower extremity as well as the stabilizing functions required during standing, walking, or other weight-bearing exercises. This complex system of muscles works synergistically to provide the power for the hip to move in all directions, as well as to stabilize the entire lower extremity during weight-bearing activities.
Pathology
A bursa is a fluid-filled sac of tissue that helps tendons slide over themselves as well as over and around bones. Trochanteric bursitis is inflammation within the bursa that sits on the outer aspect of the hip bone, greater trochanter, and is caused by irritation from the iliotibial band (ITB). The ITB is a thick, canvas-like band of tissue that starts on the outer aspect of the pelvis, runs over the bony part of the hip bone, greater trochanter, and attaches on the upper part of the leg bone, tibia. The ITB can get irritated from running, starting a new aerobic activity/exercise, or from tightness that can develop in the ITB itself. Women are more prone to trochanteric bursitis due to the shape of their pelvis compared to that of men. Trochanteric bursitis often causes pain on the outer aspect of a patient’s hip, that can be worse while sleeping on that side, prolonged sitting, or prolonged activity. The pain on the outer aspect of the hip may or may not run down the outer aspect of a patient’s leg to the knee or upper leg.
Treatment
The mainstay of treatment for trochanteric bursitis utilizes non-operative treatment measures. The Iliotibial band (ITB) is usually tight and often the muscles on the outside of the hip and leg are weak. Physical therapy focuses on first increasing the flexibility of the ITB and then strengthening the muscles on the outer aspect of the hip and leg. If the pain is severe, a steroid injection may be recommended to reduce the inflammation within the trochanteric bursa to provide some comfort when performing the exercises in therapy. If an injection is not recommended or deferred by the patient, anti-inflammatory medications will often be prescribed to help reduce the inflammation while the bursitis is being treated.
Rarely, trochanteric bursitis is not fully relieved with the above non-operative treatment measures and surgery is required. The surgery involves, releasing part of the ITB over the hip bone that is tight and removing the inflamed bursa. This procedure is done through a small incision as an outpatient procedure. Physical therapy starts within 3 days after therapy to begin range-of-motion and gentle strengthening exercises. Most patients are able to return to their activities with or without limitations, based on their pre-injury level of ambulation and function