Sonographic assessment of the anatomy and common pathologies of clinically important bursae

Abstract

High-resolution ultrasonography has many advantages in the imaging of the musculoskeletal system, when compared to other imaging methods, particularly in superficial, easily accessible parts of the body. It is a perfect diagnostic tool for visualizing the most common pathologies of the musculoskeletal system, including the bursae. Inflammation of bursae is frequent, and it can mimic other diseases of the musculoskeletal system. Therefore, knowledge of normal ultrasound anatomy of the bursae, their exact location in the human body, and the sonographic signs of their most common pathologies is essential for establishing a quick and accurate diagnosis by ultrasound. Common conditions affecting bursae, leading to bursitis, include acute trauma, overuse syndromes, degenerative diseases, inflammatory conditions (rheumatoid arthritis, psoriatic arthritis, gout etc.), infections such as tuberculosis, synovial tumors and tumor-like conditions (pigmented villonodular synovitis, osteochondromatosis), and many more. This review article presents and explains ultrasound examples of the most frequent pathological conditions affecting bursae. Images include normal and pathological conditions of bursae around the shoulder joint, elbow, hip, knee, and ankle joint.

Keywords: anatomy; bursa; high-resolution ultrasonography; inflammation.

Fig. 1.

Normal subacromial-subdeltoid bursa. There is a minimal amount of anechoic fluid within the bursa (arrows), located between the deltoid muscle (D) and the supraspinatus muscle tendon (arrowhead). H-humeral head

Fig. 2.

Bursitis. Prepatellar bursa is filled with fluid, debris, and irregular synovia (arrows). Hyperechoic edema of surrounding soft tissue can be noted. Inflammation of the superficial part of the patellar ligament is also visible (arrowhead). P-patella

Fig. 3.

A. Evaluation of the subacromial-subdeltoid bursa. Positioning of the patient and the transducer. B. Normal subacromial-subdeltoid bursa in the longitudinal plane (arrows). Arrowhead-supraspinatus tendon, H-humeral head, T-tuberculum majus, D-deltoid muscle

Fig. 4.

Communicating subacromial-subdeltoid bursitis. Communication (arrowhead) between the glenohumeral joint and the bursa (arrows) is visible through a total tear of the supraspinatus tendon. The bursa is filled with a moderate amount of hyperechoic fluid. H-humeral head

Fig. 5.

Non-communicating subacromial-subdeltoid bursitis. An increased amount of fluid in the bursa (arrows) in a patient with calcifying supraspinatus tendinopathy (filled arrow). T-tuberculum majus

Fig. 6.

A. Evaluation of the olecranon bursa. Positioning of the patient and the transducer. B. Superficial olecranon bursitis in the transverse plane (*). O-olecranon. C. Superficial olecranon bursitis in longitudinal plane (*). O-olecranon

Fig. 7.

A. Evaluation of the iliopsoas bursa. Positioning of the patient and the transducer. B. Iliopsoas bursitis in the longitudinal plane. Enlarged, fluid-filled iliopsoas bursa (arrow) is visible deep to the ileopsoas tendon (arrowhead). An increased amount of fluid in the anterior hip recess (*)

Fig. 8.

Medial collateral ligament bursitis. There is a large amount of anechoic fluid filling the bursa (*) between the superficial and deep layers of the medial collateral ligament. M-medial meniscus, T-tibia, F-femur

Fig. 9.

Evaluation of the suprapatellar bursa. Positioning of the patient and the transducer

Fig. 10.

Pigmented villonodular synovitis of the knee. The suprapatellar bursa is filled with hypoechoic fluid; irregular synovial hypertrophy (arrows). F-femur, *-quadriceps tendon

Fig. 11.

Lipohemarthrosis. A large amount of hyperechoic fluid (arrow) with fat-fluid level (filled arrow) can be visualized within the recess in a patient with plateau tibial fracture. *-quadriceps tendon, F-Femur

Fig. 12.

A. Baker’s cyst in the transverse plane, localized between the semimembranosus tendon (arrow) and the medial head of the gastrocnemius muscle (arrowhead). The cyst is communicating with the knee joint through a thin neck. F-Femur. B. Evaluation of Baker’s cyst. Positioning of the patient and the transducer. C. Baker’s cyst in the longitudinal plane. Several ossified bodies (arrows) can be seen within the cyst due to secondary osteochondromatosis

Fig. 13.

Evaluation of the prepatellar bursa. Positioning of the patient and the transducer

Fig. 14.

Prepatellar bursitis (*). The prepatellar bursa is enlarged, filled with a copious amount of anechoic fluid and debris. P-patella. Arrows-patellar ligament

Fig. 15.

Evaluation of the infrapatellar bursae. Positioning of the patient and the transducer

Fig. 16.

Superficial infrapatellar bursitis (arrows). There is a moderate amount of fluid accumulated superficially to the distal part of the patellar ligament (*)

Fig. 17.

Normal deep infrapatellar bursa can be seen as a small, triangular fluid collection (arrowhead) deep to the distal part of the patellar ligament (arrows), superficial to the tibial surface (T)

Fig. 18.

Deep infrapatellar bursitis. A lobulated, enlarged deep infrapatellar bursa (arrows) deep to the distal part of the patellar ligament (arrowhead)

Fig. 19.

Evaluation of the superficial and deep retrocalcaneal bursae. Positioning of the patient and the transducer

Fig. 20.

Deep retrocalcaneal bursitis (*) in a patient with insertional Achilles tendinopathy (arrows). The Achilles tendon is swollen, with disrupted fibrillar pattern and calcifications near the insertion. C-calcaneus