PROSCAN imaging

Diagnosis:
Calcific greater trochanteric bursitis

Findings: (Images 1 - 4)
Oval-shaped low signal loose bodies are identified within an inflamed greater trochanteric bursa on the right. The bodies measure 1.8 and less than 1 cm. (Images 1a - 4a) The signal characteristics suggest calcification or, less likely, hemosiderin. Inflammation extends from the tip of the greater trochanter to the fascial plane between the gluteus minimus and medius musculature. No marrow changes to suggest stress reaction of the right hip or trochanteric region.

Discussion:
Calcific bursitis is the primary diagnostic consideration. Infectious bursitis such as tuberculosis infection unlikely.

Greater trochanteric bursitis is inflammation of the lateral femoral trochanteric bursa which can be inflammatory, infectious or related to underlying arthropathy. Patients frequently present with lateral hip pain and paresthesias which radiate below the knee simulating symptoms of lumbar radiculopathy. A patients symptoms are often reproduced with direct palpation, thus a focused physical exam, knowledge of this disease entity and a negative neurological exam can be very helpful to suggest the diagnosis. MR imaging can be employed if the patient fails conseravative therapy, to exclude other hip pathology.

Gluteus medius and minimus strains are often misdiagnosed as primary greater trochanteric bursitis. Inflammation within the bursa is a secondary phenomenon in this injury. Care should be taken to determine the epicenter of the inflammatory process so that an accurate diagnosis can be rendered. In the above case, calcium hydroxyapatite deposition within the bursa is noted. Its presence can make treatment difficult and in some rare cases will require surgical removal.

R.I.C.E. (rest, ice, compression, elevation) therapy and local steroid and lidocaine injection are the hallmark of conservative therapy.

Aspiration of inflamed bursae is indicated when the possibility of infection or underlying arthropathy is postulated. Staphylococcus aureus is the #1 cause of sepsis related to greater trochanteric bursitis. Tuberculosis has been reported to cause deep bursal infection in the hip.