Pediatric supracondylar fracture of the humerus

Etiology

Most common < 10 years, peak age 5-8 y.o.
80% of all pediatric distal humerus fractures
2:1 males
Classification
Extension type: Extension type accounts for 90-98% of all supracondylar fx's

Gartland Classification:
I: nondisplaced

IIA: displaced, posterior cortex intact; rotationally stable

intact posterior cortex acts like a hinge
IIB: displaced, posterior cortex intact; rotationally unstable

III: completely displaced, no cortical contact

most often a medial periosteal sleeve intact when medially displaced and visa versa
Closed Reduction
Reduction Maneuver
Traction: disengages the proximal fragment from the brachialis ms
Coronal plane correction: medial or lateral translation
Axial plane correction: correction of internal rotation deformity
Distal fragment reduced: push with thumb on olecranon
Elbow flexion >100°
Pronation: tightens medial periosteal sleeve

Notes:
Closed reduction is NOT attempted in type III fx's
Reduction under flouro control is recommended
In the laterally intact periosteal sleeve, supinate to lock it in

Assessing adequacy of reduction:
Jones view: hyperflexionn shoot through elbow; distal humerus resting on c-arm for coronal reduction assessment...difficult to interpret due to imposition of the proximal forearm
Baumann's Angle: comparison to uninjured side, difference >5degrees is unacceptable
Anterior Humeral Line

Other Methods: restoration of olecranon fossa anatomy, humero-ulnar angle, crescent sign (overlapping of the ossification centers of the lateral epicondyle and olecranon on a lateral view is unacceptable)

Definitive Treatment
Type I Fracture

Immobilization: long arm cast in 90° elbow flexion, neutral forearm
Repeat radiographs @ 1 week: checking fracture hasn't drifted into varus
3 weeks: protected ROM, elbow exercises
Notes:
Conservative treatment guided by lack of displacement, rarity of NV comprismise
May or may not admit overnight for assessment of NV status, compartments

Type II Fracture

Hyperflexion required to maintain reduction
Immobilization: long arm cast, long arm cast split, or long posterior splint with lateral struts
Observe overnight for NV and compartment assessment
3 weeks: protected ROM, elbow exercises
CRPP: significant swelling, inadequate circulation with elbow flexion, rotationally unstable injury

Notes:
Millis et al CORR 1984 showed that 120degrees of flexion needed to maintain closed reduction of type II supracondylar fractures
Casting these injuries as means of definitive treatment carries risk of compartment syndrome, as swelling is not allowed in the cast...this is especially true with the greater amount of flexion used to maintain the reduction

Type III fracture:

higher energy injury
Increased swelling and soft tissue injury
Difficult reduction, therefor: "Splint it where it lies" f/b CRPP
More complications: Admit for NV and compartment assessment
CRPP Technique

Sterile draped C-arm operating surface
Lateral pin first
0.062mm small child
5/64inch older child

Starting point: lateral condyle immediately lateral to olecranon fossa
Across capitellum and distal humeral physis
Engage medial humeral cortex
2 lateral pins may achieve stability
Notes:
Maintain ~120 flx full pronation / use Jones view of elbow / may externally rotate through the shoulder to avoid moving C-arm / fracture site
First pin: don't attempt perfect center of lat cond; want to leave room for 2nd lateral pin

Medial pin:
*80-90° elbow flexion: Less elbow flexion for medial pin as more flexion will bring ulnar nerve volar into Kwire's path, and lateral pin is providing some stability. Utilize c-arm before firing to assure you are not in the ulnar groove

*Starting point: Different angle taken with medial pin will make it more transverse than lateral pin
*Mini-incision over medial epicondyle
*Spread with hemostat assuring ulnar nerve position

Post Operative Care

Leave pins protruding
Re-assess vascular status before drape removal
Splint: 60-90° elbow flexion with neutral forearm
Admit overnight for NV checks
Pin removal in 3-4 weeks: PT usually not required
Open Reduction
Indications:

Irreducible by closed methods
Vascular comprimise
Open fractures
Notes:
Wilkins Ortho Clin 1990 talked about brachialis entrapment in fracture site consistently requires open reduction
Vascular: poor color after closed reduction; kids vascular exam comments on pink warm digits as an actual palpable pulse not necessarily as important

Open Approach

Transverse Antecubital Incision
Enlarge Incision:
Medial side: proximal
Lateral side: distal

Notes:
Posterolateral displacement with NV comprimise: anteromedial approach
Consider: area of NV injury and periosteal disruption

Complications:
Neurologic Injury

5-19% of supracondylar farctures
Type III supracondylar fractures:

Median nerve 52% (especially posteromedial displacement)
Radial nerve: 28%
Most are neuropraxic injuries
Motor Recovery: 7-12 weeks
Sensory: ~6 months

Notes:
Nerve injury can also occur s/p CRPP Royce et al JPO 1991: 143 supracondylars treated CRPP 4 nerve palsies were found, ALL from medial pin. They also found an iatrogenic nerve injury rate of 2-3% after CRPP. This is why Pediatrics Ortho attendings often prefer 2 lateral pins before going medial.

Wound / Nerve Exploration Indications:

Culp et al JBJS 1990 nerve injury in supracondylar fx's: 5 months after injury with NO clinical or EMG evidence of return
Open fracture over disrupted nerve
Neurologic impairment after closed reduction

Arterial Injury
*5-12%

Shaw et al JOT 1990: immediate CRPP restored pulse in 13/17 pulseless supracondylar fractures. Their study also found that arteriography preoperatively would not have contributed to the management of these injuries as thos still lacking a pulse after CRPP were opened and explored acutely and found to have brachial artery disruption at the fracture site.
_
Angular Deformity_

Distal Humeral Physis: 20% of longitudinal growth
Remodeling: plane of motion only
NO coronal remodeling
NO axial remodeling

Cubitus Varus: Cosmetic in the short term

Recent studies show that in the long term, varus may lead to posterolateral rotary instability of the elbow
Caused by malreduction
11% due to medial distal physeal disruption
Osteotomy: cosmetic procedure
Delay until 1 year post injury to await possibility of medial growth arrest being responsible for deformity; if so lateral epiphysiodesis would accompany osteotomy

Osteotomy Options:

Lateral closing wedge osteotomy
Dome rotational osteotomy
Step-cut lateral closing wedge osteotomy
Compartment Syndrome
*1% incidence: Ottolengi et al European study with 830 supracondylars

Volkman's Contracture

Be aggressive
Compartment syndrome may be masked by median nerve disruption
Fasciotomy:

Clinical signs
Pressure >30 mm Hg OR within 30 mm Hg of DBP
Flexion-type Supracondylar

1-10% of all supracondylar
Gartland Classification
Reduction Maneuver: elbow extension

Varus force addresses anterolateral displacement
Treatment: CRPP

Casting in elbow extension difficult for patient to deal with
Gartland Classification: nondisplaced / intact anterior cortex / complete displacement usually ant lat

Across to lateral column
Cross lateral pin above olecranon fossa
Engage lateral humeral cortex