A detailed overview of the Elbow joint

1. RADIOLOGY OF THE ELBOW
JOINT
DR. SUMIT SHARMA
PG RESIDENT
DEPT. OF RADIODIAGNOSIS
SLIMS, PUDUCHERRY

2. Normal Elbow Anatomy
The elbow is a complex synovial joint formed by the articulations of
the humerus , the radius and the ulna.
Very important to be aware of pediatric growth centers
CRITOE

3. Osteology of Elbow

4. Articulations
• The elbow joint is made up of three
articulations :
• radiohumeral: capitellum of the humerus with
the radial head
• ulnohumeral: trochlea of the humerus with
the trochlear notch (with separate olecranon
and coronoid process articular facets) of the
ulna

5. • radioulnar: radial head with the radial notch
of the ulna (proximal radioulnar joint)
In full flexion, the coronoid process is received by
the coronoid fossa and the radial head is received by
the radial fossa on the anterior surface of the
humerus and in full extension the olecranon process
is received by the olecranon fossa on the posterior
aspect of the humerus.

6. Articulations

7. Normal Alignment
• Anterior humeral line- line drawn along
anterior surface of humeral cortex
should pass through the middle
third of the capitellum
• Radiocapitellar line- Line
drawn through the proximal
radial shaft and neck
should pass through to
the articulating capitellum

8. Ligaments
• Medial (ulnar) collateral ligament complex
• Lateral (radial) collateral ligament complex
• Oblique cord
inconstant thickening of supinator muscle
fascia and functionally insignificant
runs from tuberosity of the ulna to just distal
to radial tuberosity

9. • Quadrate ligament (of Denuce)
thickening of the inferior aspect of the joint
capsule
runs from just inferior to the radial notch of
the ulna to insert to the medial surface of the
radial neck
• Anular (orbicular) ligament
Encircles the head and retains it in contact
with the radial notch of the ulna.

10. • Joint capsule
The joint capsule has two layers, deep and
superficial, and attaches proximally to the
radial, coronoid and olecranon fossae.
Distally, it attaches to the annular ligament of
the radius and coronoid process of the ulna .
The volume of the joint capsule is 24-30 mL

11. Ligaments

12. Fat pads
• There are three fat pads of the elbow, which
sit between the two layers of the joint
capsule, making them extra-synovial:
• coronoid fossa fat pad (anterior)
• radial fossa fat pad (anterior)
• olecranon fossa fat pad (posterior)

13. Bursae
• superficial olecranon bursa: lies between the
olecranon and the subcutaneous tissue
• subtendinous olecranon bursa: lies between
olecranon and triceps brachii tendon
• intratendinous olecranon bursa: variably lies in
the triceps brachii tendon
• bicipitoradial bursa: lies between biceps brachii
distal tendon and ant. radial tuberosity

14. Fat Pads and Bursae

15. Relations
• anteriorly: biceps brachii tendon; brachialis
muscle, median nerve, brachial artery
• posteriorly: olecranon bursae, triceps
brachii tendon
• laterally: common extensor tendon; supinator
muscle
• medially: ulna nerve

17. Blood & Nerve supply
• Arterial supply is via
anastomotic (medial, lateral
and posterior) arcades
formed by branches of
the radial, ulnar and brachial
arteries.
• Articular branches of the
radial, ulnar, median and
musculocutaneous nerves.

18. Movements
• The elbow is a trochoginglymoid
(combination hinge and pivot) joint :
• The hinge component (allowing flexion-
extension) is formed by the ulnohumeral
articulation
• The pivot component (allowing pronation-
supination) is formed by the radiohumeral
articulation and the proximal radioulnar joint

19. Variant anatomy
• Synovial folds
 thin projections of synovial membrane (inner layer of
joint capsule)
 may be confused for intra-articular loose bodies on
MRI
• Capitellar and Olecranon pseudodefects
 normal areas devoid of articular cartilage
 can be mistaken on MRI for impaction injuries or
osteochondral defects
• Accessory ossicles
 os supratrochlear dorsale
 patella cubiti (very rare)

20. Elbow Trauma
• 6% of all fractures and dislocations involve
elbow
• Most common fractures differ between adults
and children
– M.C. in adults- radial head and neck fxs.
– M.C. in children- supracondylar fxs.
• Complex anatomy requires 4 views for
adequate interpretation
– AP in extension, medial oblique, lateral and axial
olecranon (Jones view)

21. Signs of Fracture
• Usual signs may not be readily visible
– Fracture line, cortical disruption, etc.
• Soft tissue signs can indicate fracture
– Fat pad sign
• On lateral, might see fat pad parallel to anterior
humeral cortex, but should never see posterior fat pad
• With effusion, anterior may be displaced and will be
shaped like a sail (sail sign)

22. Fat Pad Sign
• Posterior fat pad is normally buried in olecranon fossa
and not visible
– Becomes elevated and visible with joint effusion
• Effusion (acute capsular swelling) can be from any origin (hemorrhagic,
inflammatory, infectious, traumatic, etc.)
• Ant. fat pad may be obliterated, so post. Fat pad is more
reliable when visible

23. Distal humerus fractures
• 95% extend to articular surface
• Classified according to relationship with
condyle and shape of fracture line
– Supracondylar, intercondylar, condylar and
epicondylar

24. Supracondylar Fractures
• Most common elbow fracture in children (60%)
• Fracture line extends transversely or obliquely
through distal humerus
above the condyles
• Distal fragment usually
displaces posteriorly
Normal

25. Intercondylar fracture
• Fracture line extends between medial and
lateral condyles and extends to supracondylar
region
– Results in T or Y shaped configuration for fracture
• Called trans-condylar if it extends through
both condyles

26. Epicondylar fracture
• Usually avulsion from traction of respective
common flexor (medial) or extensor (lateral)
tendons
• Medial epicondyle
avulsion common in
sports with strong
throwing motion
(little leaguer’s elbow)

27. Fractures of Proximal Ulna
• Olecranon fx.- direct trauma or avulsion by
triceps tendon
• Coronoid process fx.- avulsion by brachialis or
impaction into trochlear fossa
– Rarely isolated;
usually associated
with post. elbow
dislocation

28. Fractures of Proximal Radius
• M.C. adult elbow fx. (50%)
• FOOSH transmits force causing impaction of
radial head into capitellum
• Chisel fracture- incomplete fracture of radial
head that extends to center of
articular surface
• Usual rad. signs (fx. Line, articular
disruption) may not be visible
– May be occult; fat pad sign is good
indicator of occult fx.

29. Fractures of the forearm
• Isolated ulnar fractures
• Isolated radial fractures
• Bony rings usually can't be fractured in one
place without disruption somewhere else in
the ring
• 60% or forearm fractures involve both bones
(BB fractures)
• These fractures usually have associated
displacement with angulation and rotation

30. Isolated Ulnar Fractures
• Distal shaft (Nightstick fx.)- direct
trauma
• Proximal shaft (Monteggia’s fx.)-
fx. of proximal ulna with
dislocation of radius

31. Isolated Radial Fractures
• Most frequent is a Galeazzi’s fx. (reverse
Monteggia’s fx.)
– Fracture of distal radial shaft
with dislocation of distal
radioulnar joint
– Rare, but serious injury

32. Dislocations of Elbow
• 3rd m.c. dislocation in adults behind shoulder and
interphalangeal joints
– More common in children
• Classified according to displacement of radius and
ulna relative to humerus
– Posterior, posterolateral, anterior, medial and
anteromedial
• Posterior and posterolateral - more common
– 85-90% of all elbow locations
– 50% have associated fractures

33. Pulled Elbow
• AKA nursemaid’s elbow
• Occurs when child’s hand is pulled, traction of arm
causes radial head to slip out from under annular
ligament and traps the ligament in the radiohumeral
articulation
• Immediate pain; stuck in mid-pronation due to pain
• No radiographic pain
• Supination reduces the dislocation and ends pain,
usually during positioning of lateral radiograph

34. Case Study

35. Case of Mrs. X
• Here is a case of a female patient with acute
trauma of the right elbow joint.
• Lets have a look at her Right Elbow X-ray AP
and lateral view.

36. AP
LAT

37. • Lets also have a look at her right elbow CT
images…..

39. Mason classification
• The Mason classification is used to classify radial head
fractures and is useful when assessing further treatment
options .
• type I: non-displaced radial head fractures (or small marginal
fractures), also known as a "chisel" fracture
• type II: partial articular fractures with displacement (>2mm)
• type III: comminuted fractures involving the entire radial
head
– IIIa: fracture of the entire radial neck, with the head completely
displaced from the shaft
– IIIb: articular fracture involving the entire head, consisting of more
than two large fragments
– IIIc: fracture with a tilted and impacted articular segment
• type IV: fracture of the radial head with dislocation of the
elbow joint

40. What is your diagnosis?

41. My Diagnosis
Marginal rim fracture of the head of the
Radius with intra-articular dispensation of
fractured fragments(Mason’s Type IIIb) in the
Right Elbow.

42. Treatment
• In general type I injuries can be treated
conservatively whereas type II injuries require
open reduction and internal fixation (ORIF).
Type III injuries often require early complete
excision of the radial head .

43. Thank You