Medial epicondylar fractures of the humerus

Cite this article as:
Lisa Dunlop. Medial epicondylar fractures of the humerus, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.21036

In this section, we will mainly discuss medial epicondylar fractures. Medial condylar fractures are a rare pattern of fracture and managed in a similar manner to lateral condylar fractures. It is important to differentiate between medial condylar and epicondylar fractures. Condylar fractures are intra-articular and require urgent open reduction and internal fixation.

Lateral condylar fractures of the humerus

Cite this article as:
Lisa Dunlop. Lateral condylar fractures of the humerus, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.21030

Six-year-old William was playing hopscotch in the playground but fell, landing on his left outstretched hand. Afterwards, he complained of left elbow pain and was taken to the local Emergency Department. He was told that he had a lateral condylar fracture of the humerus…

Epidemiology 

This is a relatively common fracture in the paediatric population and occurs mainly in children below the age of 7 years old, with a mean age of 6. It accounts for approximately 10-20% of paediatric elbow fractures and is the second most common intra-articular fracture.

History 

The most common aetiology for this fracture is a fall onto an outstretched hand. The patient will complain of pain to the lateral aspect of the elbow. The level of pain may be low in minimally displaced fractures.

Examination

Have a look at our post on elbow examination for tips on how to do a full assessment of a child’s elbow.

Inspection of the joint will reveal an elbow with swelling to the lateral aspect. There is usually minimal deformity. Bruising may indicate a brachioradialis tear and therefore likely instability. Tenderness is usually limited to the lateral aspect and crepitus may be palpated on movement. Wrist flexion and extension may reproduce the pain.

It is important to carefully examine the joint below and above the injured area. Don’t forget to examine the rest of the child for other injuries.

Remember to be suspicious of non-accidental injury in cases where there are inconsistencies in the history and injury type.

Investigations

AP and lateral x-rays of the elbow are required. Oblique views can be valuable if no fracture is seen on lateral or AP views but clinical suspicion remains. This is where your knowledge of the ossification centres comes into play (for detail on this see CRITOE). The ossification centres appear on x-rays in the order: Capitellum, Radial head, Internal epicondyle, Trochlea, Olecranon and the External epicondyle, also known as the lateral condyle. The lateral epicondyle appears at the age of 8-12 years old and fuses at age 12-14 years old.

The paediatric elbow is largely cartilaginous. Lateral condylar fractures often only affect the cartilaginous part of the humerus. As cartilage is not radiopaque, the true extent of the fracture is often not fully understood when looking at the x-ray.

The presence of anterior and posterior fat pads may often be the only indication that a fracture is present.

The most commonly associated fracture is the ipsilateral elbow dislocation (usually posterolaterally) and ipsilateral humeral fractures (most commonly the olecranon). Ensure you obtain radiographs for other suspected fractures.

 Lateral condyle fractures can be classified depending on their x-ray appearances.

Classification

There are several different classification methods. The most common classifications as below.

Milch Classification
Type 1The fracture line is lateral to the trochlear groove… not into the humero-ulnar joint
Type 2The fracture line is medial to the trochlear groove and is, therefore, a fracture-dislocation and unstable.
Milch Classification
Jakob Classification
Stage 1<2mm displacement, which indicates intact cartilaginous hinge 
Stage 22-4mm of displacement 
Stage 3>4mm displacement with rotation of the fragment 
Jakob Classification

Immediate treatment in the ED

Provide immediate adequate analgesia to the child prior to any examination or investigation.

If the fracture is open, conservatively manage the wound, consider tetanus status and antibiotics.

Keep the child nil by mouth as they may need urgent surgery.

Treatment following imaging

Treatment depends on the degree of displacement of the fracture.

Due to the high complication rate of these fractures, all lateral condylar fractures should be referred for to the on-call orthopaedic team while in the Emergency Department.

Jakob classificationTreatment optionFollow up
Stage 1 (<2mm of displacement)Conservative management with immobilisation with above elbow cast to 90 degrees.Weekly imaging in fracture clinic with the cast in place for 4-6 weeks.
Stage 2 and 3 (> 2mm with or without rotation)These all must go to theatre and have closed reduction with percutaneous pinning or open reduction with screw fixation.3-6 weeks in above-elbow cast and orthopaedic follow up.

Areas of controversy

Serial radiographs are often recommended in the management of conservative management minimally or undisplaced lateral condylar fractures. A systematic review by Tan et al 2018 found that serial X-rays have no clinical significance. However, if the 1 week up x-ray is not satisfactory, this should be followed up appropriately under the patient’s treating orthopaedic team.

Potential complications

This type of fracture is associated with a high rate of complications, which usually develop later, during the healing process.

The reduction must be accurate. If there is malunion, the fragment does not adequately unite or the epiphyseal plate is damaged then complications may occur:

  • Stiffness is the most common complication, usually fully resolving by 48 weeks.
  • Delayed union occurs if the fracture has not healed after 6 weeks. This usually occurs if the fracture visible at 2 weeks.
  • Non-union is more likely when delayed union occurs.
  • Cubitus valgus deformity occurs with lateral physeal growth arrest.
  • Delayed “tardy ulnar palsy” may develop as the child grows and the ulnar nerve is stretched across the elbow with valgus deformity.
  • Avascular necrosis may develop 1-3 years after the fracture.
Image from wikimedia.org

Do not miss bits

Lateral condylar fractures of the humerus can present with minimal pain or deformity and can be missed (16.6% misdiagnosed as presented by Tan et al 20181). Due to the high rate of complication, it is important that we do not miss these fractures.

William was found to have an isolated Jakob stage 3 type lateral condylar fracture and was taken to theatre that evening. Open reduction was required, and internal screw fixation secured the fragment. His cast was removed 4 weeks after and his joint mobility continues to improve.

References

Bowden G, McNally MA, Thomas RYW, Gibson A. 2013. Oxford Handbook of Orthopaedics and Trauma, Oxford Medical Publications. Page 564-5

Dandy DJ, Edwards DJ, 2003. Essential Orthopaedics and Trauma, Fourth Edition, Churchill Livingstone, page 197.

Raby N, Berman L, Morley S, de Lacey G. 2015. Accident and Emergency Radiology: A survival Guide Third Edition, Sauders Elsevier page 106-110.

Shaath k, Souder C, Skaggs D. 2019. Orthobullets, Lateral Condyle Fracture – Pediatric Accessed 06/04/2019 https://www.orthobullets.com/pediatrics/4009/lateral-condyle-fracture–pediatric

Tan SHS, Dartnell J, Lim AKS, Hui JH. Paediatric lateral condyle fractures: a systematic review. Arch Orthop Trauma Surg. 2018 Jun;138(6):809-817. doi: 10.1007/s00402-018-2920-2. Epub 2018 Mar 24. Review. PubMed PMID: 29574555.

CRITOE Quick Quiz

Cite this article as:
Tessa Davis. CRITOE Quick Quiz, Don't Forget the Bubbles, 2014. Available at:
https://doi.org/10.31440/DFTB.4507

This quick quiz is to test your CRITOE knowledge. See this post for how to interpret an elbow x-ray.

Click on the image to see them in full size…

 

Q1: What age is this child?

Q1

View Q1 answer

This child is 6 years old.

Ossification centres develop in the order CRITOE (1, 3, 5, 7, 9, 11)

CRITOE

Capitellum (1 year)

Radial head (3 years)

Internal (medial) epicondyle (5 years)

Trochlear (7 years)

Olecranon (9 years)

External (lateral) epicondyle (11 years)

 

On these XRs you can see C, R and I (I not usually visible on the lateral) so the child is roughly 6 years old.

Q1

Understanding ossification centres order of development is crucial to recognising paediatric elbow fractures.

Q2: What is the abnormality in the XR of this child who sustained a fall onto the lateral aspect of her elbow?

lateral condyle avulsion

View Q2 answer

Lateral condyle avulsion.

The capitellum, radial head and the start of internal epicondyle are there (approx. 5 years old).  There is no trochlear or olecranon and therefore there should be no lateral epicondyle.  The small area shown in red (below) is an avulsed lateral condyle.

lateral condyle avulsion annot

Lateral condyle fractures account for 20% of all elbow fractures in children and are most common in 5-7 year olds after falling onto an outstretched arm.  All should be discussed with ortho as there is a high risk of complications if not treated properly.

The displacement (gap between the distal humerus and the fractured condyle) needs to be measured.

Undisplaced fractures can be put in a long-arm backslab (with 90 degree elbow flexion). Displaced fractures with a <2 mm gap sometimes require closed reduction.  Displaced fractures with a >2 mm gap or angulation of the lateral condyle will require surgical intervention.

Q3: What is the abnormality in this X-ray of a 12 year old boy who fell onto his outstretched hand (with the elbow extended)?

medial epicondy latmedial epicondyle ap

View Q3 answer

Medial epicondyle avulsion.

This child is 12 so should have all CRITOE ossification centres.  Checking through one by one, the medial epicondyle is missing. In fact it has been displaced.

Medial epicondyle ap annotmedial epicondyle annot lat

The yellow lines show where it should be, the red lines show where it is.

On the lateral you can actually see the medial epicondyle which you should not be able to do in a good lateral view.

Medial epicondyle fractures occur between 7-15 years (they account for 10% of elbow fractures in children). They are often associated with elbow dislocation (50%). The degree of displacement of the medial epicondyle needs to be assessed.

Undisplaced or minimally displaced (<5 mm) fractures will not need surgical repair and can be managed in a long arm backslab (with 90 degrees elbow flexion). Displacement of 5-15 mm requires ortho input – surgical intervention usually depends on multiple factors (e.g. age, dominant hand, sports involvement).  Displacement of >15 mm or neurovascular compromise (ulnar nerve palsy) will require ORIF.

Q4: What is the abnormality in this child who fell directly onto her elbow?

olecranon

View Q4 answer

Olecranon fracture.

The ossification centres in the lateral view show a capitellum but no radial head (see below).

olecranon annot

The fragment on the end of the ulnar must be an olecranon fracture as there is no ossification centre yet developed.

These fractures account for 5% of elbow fractures in children.  They are often associated with other injuries so thoroughly check the rest of XR.

Undisplaced, or minimally displaced fractures can be put into a long arm backslab (90 degree elbow flexion).  Displaced fractures should be referred to ortho as will likely need surgical intervention.