Olecranon Bursitis
Olecranon bursitis refers to inflammation of the olecranon bursa. The olecranon bursa is a subcutaneous sac that overlies the olecranon process and contains a small amount of fluid to prevent against injury of subcutaneous tissue and skin from the uncovered bony olecranon.
Pathology
Etiology
Bursitis can develop secondary to many causes:
- excessive use - e.g. student's elbow
- trauma
- acute trauma
- repetitive trauma
- infection - septic
- inflammation - rheumatoid arthritis, gouty arthropathy and CPPD
Radiographic features
Plain film
Lateral radiograph of the elbow reveals soft tissue swelling superficial to the olecranon. Traumatic fracture or calcification in gout or CPPD may be evident.
Ultrasound
May show a fluid collection in the olecranon bursa, features of synovial proliferation and/or hyperemia. A small proportion of patients may also show presence of an associated loose body or features of associated triceps tendonitis (+/- calcifications) .
CT
- fluid density at the subcutaneous tissue superficial to the elbow
MRI
Bursal fluid collection has the following features:
- T1: hypointense
- T2: mainly hyperintense
- C+ (Gd): enhancement of bursal margins
Triceps brachii muscle and subcutaneous edema as well as elbow joint effusion may be seen.