Distal Humeral Physeal Fractures Mohammad Ali Tahririan MD Department of Orthopedics Kashani Hospital

Next to those of the distal radius, injuries to the distal humeral physes are the most common physeal injuries.

total distal humeral physis: First 2-3 Y Lat. Conylar physis: 6 Y Med. Condylar physis: 8-12 Y Medial epicondylar apophysis: 11-12 Y

Fractures Involving the Lateral Condylar Physis

16.9% of distal humeral fractures only occasionally associated with injuries outside the elbow region

Classification

Mechanism of Injury

Two mechanisms have been suggested: "

push-off" and "pull-off"

The pull-off or avulsion theory has more advocates than the push-off mechanism

The more common type of fracture, which extends to the apex of the trochlea, is probably a result of avulsion forces on the condyle, with the olecranon's sharp articular surface serving to direct the force along the physeal line into the trochlea.

When a child falls forward on his or her palm with the elbow flexed, the radial head is forced against the capitellum and may cause the less common Milch type I physeal fracture that courses through the ossific nucleus of the capitellum.

Signs and symptoms

Key: location of soft tissue swelling concentrated over the lateral aspect of the distal humerus. Stage I: only local tenderness at the condylar fracture site, which may be increased by forcibly flexing the wrist.

Stage II or III: local crepitus with motion of the lateral condylar fragment.

A major diagnostic difficulty lies in differentiating this fracture from a

fracture of the entire distal humeral physis

. In a young child in whom the condyle is unossified, an

arthrogram or MRI

may be helpful

Treatment

If the fracture is minimally displaced on radiograph ( less than 2 mm) and the clinical signs also indicate there is reasonable soft tissue integrity, we simply immobilize the elbow in a long-arm cast with the forearm in neutral rotation and the elbow flexed 60 to 90 degrees.

If there is any question about the stability MRI or varus stress test Gentle varus stress views with the forearm supinated and the elbow extended should be taken.

Percutaneous Pins

For fractures with stage II (2 to 4 mm), varus stress views or arthrography should be obtained.

If the fracture is stable, percutaneous pinning is indicated

Open Reduction

If the fracture is grossly unstable, or satge III

ORIF

Complications

Non union

Treating is a difficult dilemma.

No treatment progressive cubitus valgus deformity Patients are usually asymptomatic except for those with high demand athletic or labor activities. A mild flexion contracture of the elbow is present, but the cubitus valgus deformity is more cosmetic than functional.

If surgery is performed, the potential risks of osteonecrosis and loss of elbow motion must be considered.

A large metaphyseal fragment · Displacement of less than 1 cm from the joint surface An open, viable lateral condylar physis

Indication of surgery

:

in patients with a nonunion who have cosmetic concerns but no functional complaints, treatment is: supracondylar osteotomy

√√√

osteosynthesis

√

note

patients with asymptomatic nonunion, cubitus valgus deformity, and symptomatic tardy ulnar nerve palsy should be treated with : Anterior transposition of the ulnar nerve .

Lateral Spur Formation

Lateral condylar spur formation is one of the most common deformities.

Cotton believed that it is caused by coronal rotation of the distal fragment, which tends to displace the flap of periosteum associated with the distal fragment laterally.

This periosteum then produces new bone formation in the form of a spur.

The spur occurs after both nonoperative and operative treatment

.

After nonoperative treatment

, a smooth outline mild cubitus varus /pseudovarus .

After operative treatment

a more irregular outline and is usually the result of hypertrophic bone formation from extensive dissection

So

Before treatment of lateral condylar fractures, the parents may be told that either: lateral overgrowth with mild cubitus varus Or lateral spur may develop, regardless of the treatment method.

They should be told that this mild deformity is usually not of cosmetic or functional significance

Cubitus Varus

Incidence is as high as 40% after operative treatment and nonoperative treatment.

Dilemma ???

Posttraumatic cubitus varus deformity may predispose a child to subsequent lateral condylar fracture and should be viewed as more than just a cosmetic deformity. They recommended valgus supracondylar osteotomy of the distal humerus.

The cubitus varus deformity is rarely severe enough to cause concern or require further treatment.

Cubitus valgus

Cubitus valgus is much less common after united lateral condylar fractures than cubitus varus. As with cubitus varus, it is usually minimal and is rarely of clinical or functional significance .

Neurologic Complications

Acute Nerve Injuries Tardy Ulnar Nerve Palsy

PIN and radial nerve injury after ORIF gradual in onset. Motor loss occurs first, with sensory changes developing somewhat later.

Subcutaneous anterior transposition of the nerve.

Osteonecrosis

Osteonecrosis is most commonly associated with the extensive dissection necessary to effect a late reduction or from loss of the blood supply at the time of injury.

Osteonecrosis is rare in fractures of the lateral condylar physis that receive little or no initial treatment and result in nonunion

If the fracture unites, osteonecrosis of the lateral condyle reossifies over many years

Fractures of the Capitellum

Fractures of the capitellum involve only the true articular surface of the lateral condyle Generally, this fragment comes from the anterior portion of the distal articular surface.

In adults, these fractures are not uncommon, but they are rare in children.

Classification

Two types:

The second, or Kocher Lorenz, type is more of a pure articular. This type of fracture is rare in children.

The first is the more common Hahn-Steinthal type,I which usually contains a rather large portion of cancellous bone of the lateral condyle.

Mechanism of Injury

The most commonly accepted mechanism is that the anterior articular surface of the lateral condyle is sheared off by the radial head.

The presence of cubitus recurvatum or cubitus valgus seems to predispose the elbow to this fracture pattern.

Treatment

If the fragment is: large acute and if an anatomic reduction can be achieved with a minimum of open manipulation or dissection ORIF with two small cannulated screws from posterior to anterior through a lateral approach.

treatment

If the fracture is : old comminuted or if there is little bone in which to engage the screw threads simple excision

Fractures Involving the Medial Condylar Physis

rare in skeletally immature children less than 1% of fractures involving the distal humerus.

Occur later than lateral condylar fractures

Mechanism of Injury

Mechanism of Injury

Classification

More common

Diagnosis

Clinically and on radiographs, a fracture of the medial condylar physis is most often confused with a fracture of the medial epicondyle.

Med. Swelling Valgus instability Elbow Disloction/ Subluxation Ulnar paresthesia Fat pad sign Med. Condlye phsis Med. Epicnodyle apophysis √√√ √√√ √√√ √√√ Post. Med. Sx Post.Lat. Dx √√√ √√√ √√√

――――

If the true location of the fracture line is questionable in a child younger than 8 to 10 years of age with significant medial elbow ecchymosis:

Arthrography or MRI

Treatment Type I

posterior splint

( Follow-up radiographs at weekly intervals are taken to ensure there is no late displacement.)

Types II and III

ORIF

Complication

Both cubitus varus and valgus deformities have been reported in patients whose fractures united uneventfully. secondary stimulation or overgrowth of the medial condylar fragment

Cubitus Valgus

decreased growth of the trochlea, possibly caused by a vascular insult

Cubitus varus

if the fracture is untreated nonunion Cubitus varus

Fractures Involving the Entire Distal Humeral Physis

Most fractures involving the entire distal humeral physis occur before the age of 6 or 7.

The younger the child is, the greater the volume of the distal humerus that is occupied by the distal epiphysis will be

The fracture lines do not involve the articular surface, so, loss of elbow motion is unlikely if malunion occurs.

A hyperextension injury in this age group is more likely to result in a physeal separation than a bony supracondylar fracture.

Mechanism of lnjury

The exact mechanism of this injury is unknown and probably varies with the age group involved physis is more likely to fail with

rotary shear forces

than with pure bending or tension forces.

Young infants have some residual flexion contractures of the elbow; this prevents the hyperextension injury that results in supracondylar elbow fractures in older children.

Rotary forces on the elbow, which can be caused by child abuse or birth trauma in young infants, are probably more responsible for this injury.

Classification

Group A fractures

occur in

infants up to 12 months

of age, before the secondary ossification center of the lateral condylar epiphysis appears. They are usually Salter-Harris type I physeal injuries.

This injury is often not diagnosed due to the lack of an ossification center in the lateral condylar epiphysis.

Classification

Group B fractures

occur most often in children

12 months to 3 years

of age in whom there is definite ossification of the lateral condylar epiphysis. Although there may be a small flake of metaphyseal bone, this is also essentially a type I Salter-Harris physeal injury

Classification

Group C fractures

occur in older children, from

3 to 7 years

of age and result in a large metaphyseal fragment that is most commonly lateral but can be medial or posterior.

These fractures are almost

always extension-type

injuries with the distal epiphyseal fragment posterior to the metaphysis

note

If differentiation of this injury from an intra-articular fracture is uncertain

Arthrography or MRI

In neonates and infants in whom ossification has not begun

Ultrasonography

Treatment

Group A CR + Splint

The elbow is initially manipulated into extension to correct the medial displacement.

Group B/C CRIF

we perform the manipulation with the patient under general anesthesia and secure the fragment with two lateral pins

note

If treatment is delayed more than 3 to 5 days If the epiphysis is not freely movable .

Simple splint or cast

Complication

Neurovascular Injuries

:Rare probably because the fracture fragments are covered with physeal cartilage and do not have sharp edges as do other fractures in this area. In addition, the fracture fragments are usually not markedly displaced.

Nonunion

: Rare

Malunion

: Common Significant cubitus varus deformity is common after this injury( but less than supracondylar fractures).

Osteonecrosis

: Rare