MRI of the elbow is a fairly frequent examination in musculoskeletal radiology practice and not quite as common in general radiological practice. This approach is an example of how to create a radiological report of an elbow MRI with coverage of the most common anatomical sites of possible pathology, within the elbow without claim for completeness.
Systematic review
A systematic review in the MRI of the elbow is essential since elbow anatomy, pathologies and injury patterns and are rather complex and only rarely lead to an abnormality of a single structure but rather show diverse findings which might need to be addressed in further patient management.
Bones
The bony structures of the elbow, the pictured distal humerus with the trochlea, capitellum and the two epicondyles, the radial head and the proximal ulna with the olecranon are assessed:
Joint space and joint capsule
- assessment of the following structures:
- joint space, joint effusion if present and possible intra-articular fragments or loose bodies
-
synovia
- synovial thickening and hyperenhancement and other abnormalities
- elbow synovial fold syndrome
Ulnohumeral articulation
Assessment of the following structures:
- ulnohumeral articular cartilage and subchondral bony structures
- chondral and osteochondral injury, subchondral fractures and subchondral cysts and or osteoarthritic changes of the trochlea and olecranon
- posterior compartment
- subchondral sclerosis, osteophytes in valgus extension overload syndrome and posteromedial impingement
- coronoid process
- medial (ulnar) collateral ligament complex (anterior and posterior bundle)
- medial epicondyle
- common flexor and pronator origin
Triceps tendon, ulnar nerve and posterior soft tissues
Assessment of the following structures:
- distal triceps tendon
- variant anatomy
- triceps tendinopathy, triceps bony avulsion, tendon rupture
- olecranon bursa
-
cubital tunnel and ulnar nerve
- variant anatomy: anconeus epitrochlearis muscle, thickened or absent retinaculum
- ulnar nerve dislocation
Radiocapitellar articulation and proximal radio-ulnar joint
Assessment of the following structures:
- radiocapitellar cartilage and subchondral bony structures
- chondral and osteochondral injury, subchondral fractures and subchondral cysts, osteoarthritic changes of the capitellum and radial head
- lateral radiocapitellar compression, Osborne-Cotterill lesion
- lateral (radial) collateral ligament complex with the lateral ulnar collateral ligament and radial collateral ligament and the annular ligament
- medial epicondyle
-
common extensor origin
- tennis elbow, tendon or muscle injury/tears
- variant anatomy: additional radial wrist extensor muscles
Pitfalls
Distal biceps tendon
Assessment of the distal biceps tendon insertion:
- biceps tendon rupture, partial tears
- postoperative changes, re-tear, heterotopic ossification
Volar soft tissues and median and radial nerves
Assessment of the following structures:
-
brachialis, brachioradialis, supinator muscles, pronator teres muscle
- muscle edema, muscle injury, brachialis tendon avulsion
- median nerve
- radial nerve (between brachialis and brachioradialis muscle Arcade of Frohse)