Introduction
  • Overview
    • supracondylar fractures are one of the most common traumatic fractures see in children and most commonly occur in children 5-7 years of age from a fall on an outstretched hand
      • treatment is usually closed reduction and percutanous pinning (CRPP), with the urgency depending on whether the hand remains perfused or not. 
  • Epidemiology
    • incidence
      • extension type most common (95-98%)
      • flexion type less common (<5%)
    • demographics
      • occur most commonly in children aged 5-7years
      • M = F
  • Pathophysiology
    • mechanism of injury
      • fall on outstretched extremity
  • Associated injuries
    • neuropraxia
      • anterior interosseous nerve (AIN) neurapraxia (branch of median n.)
        • the most common nerve palsy seen with supracondylar humerus fractures    
      • radial nerve palsy
        • second most common neurapraxia (close second)
      • ulnar nerve palsy
        • seen with flexion-type injury patterns    
      • nearly all cases of neurapraxia following supracondylar humerus fractures resolve spontaneously
        • further diagnostic studies are not indicated in the acute setting
    • vascular compromise (5-17%)
      • rich collateral circulation can maintain circulation despite vascular injury
    • ipsilateral distal radius fractures
Anatomy
  • Ossification centers of elbow
    • age of ossification/appearance and age of fusion are two independent events that must be differentiated   
      • e.g., internal (medial epicondyle) apophysis
        • ossifies/appears at age 6 years (table below)
        • fuses at age ~ 17 years (is the last to fuse) 
Ossification center
Years at ossification (appear on xray) (1)
 Years at fusion (appear on xray) (1)
Capitellum
1
 12
Radial Head
4
 15
Medial epicondyle
6
 17
Trochlea
8
 12
Olecranon
10
 15
Lateral epicondyle
12
  12
(1) +/- one year, varies between boys and girl
 
Classification
 
Gartland Classificaiton 
(may be extension or flexion type)
Type I
  • Nondisplaced
    • beware of subtle medial comminution leading to cubitus varus, which technically means it is not a Type I Fracture, and it requires reduction and pinning
  • Treated with cast immobilization x 3-4wks, with radiographs at 1 week
  
Type II
  • Displaced 
    • posterior cortex and posterior periosteal hinge intact 
  • Deformity is in the sagittal plane only
  • Typically treated with CRPP
  
Type III
  • Displaced, often in 2 or 3 planes
  • Treated most commonly with CRPP or open reduction if needed
Type IV*,**
  • Complete periosteal disruption with instability in flexion and extension
  • Diagnosed with examination under anesthesia during surgery
  • Treated most commonly with CRPP or open reduction if needed

  SCH flexed
Medial comminution* 
  • Collapse of medial column, loss of Baumann angle 
    • leads to varus malunion/classic gunstock deformity
    • may or may not be associated with a sagittal plane deformity
  • Treated with CRPP, often requires significant valgus force to reduce
  
Flexion type
  • Mechanism of injury is usually a fall on the olecranon
  • Treated with CRPP
  • More likely to require open reduction 
  
*not a part of original Gartland classification   
**diagnosed intraoperatively when capitellum is anterior to AHL with elbow flexion and posterior with extension on lateral XR  
 
Presentation
  • Symptoms
    • pain
    • refusal to move the elbow
  • Physical exam
    • inspection
      • gross deformity
      • swelling
      • ecchymosis in antecubital fossa
    • motion
      • limited active elbow motion
    • neuro exam
      • neurovascular exam must be done before any reduction maneuver to be certain nerve or vascular injury is not iatrogenic (stuck in fracture site) 
      • Evaluate for
        • AIN neurapraxia post
          • unable to flex the interphalangeal joint of the thumb and the distal interphalangeal joint of the index finger (can't make A-OK sign)
        • median nerve injury
          • loss of sensation over volar index finger
        • radial nerve neurapraxia
          • inability to extend wrist, MCP joints, thumb IP joint
            • PIP and DIP can still be extended via intrinsic function (ulnar n.)
    • vascular exam
      • assess pulse
        • present or absent by palpation
        • present or absent by biphasic doppler pulse
      • assess vascular perfusion
        • well perfused
          • warm
          • pink
        • poorly perfused
          • cold
          • pale
          • arterial capillary refill > 2 seconds
Imaging
  • Radiographs
    • recommended views
      • AP and lateral x-ray of the elbow (really of the distal humerus)
    • findings
      • posterior fat pad sign 
        • lucency on a lateral view along the posterior distal humerus and olecranon fossa is highly suggestive of occult fracture around the elbow
    • measurement
      • displacement of the anterior humeral line
        • anterior humeral line should intersect the middle third of the capitellum in children > 5 years old, and touches the capitellum in children in children <5.  
        • capitellum moves posteriorly to this reference line in extension type fractures and anteriorly in flexion type fractures 
      • alteration of Baumann angle  
        • Baumann's angle is created by drawing a line parallel to the longitudinal axis of the humeral shaft and a line along the lateral condylar physis as viewed on the AP image 
        • normal is 70-75°, but best judge is a comparison of the contralateral side
        • deviation of >5-10° indicates coronal plane deformity and should not be accepted
  • Angiography
    • is typically not indicated
Treatment
  • Nonoperative
    • long arm casting with less than 90° of elbow flexion
      • indications
        • warm perfused hand without neuro deficits and
          •  Type I (non-displaced) fractures 
          •  Type II fractures that meet the following criteria
            • anterior humeral line intersects the capitellum
            • minimal swelling present
            • no medial comminution
      • technique
        • typically used for 3 weeks 
        • repeat radiographs at 1 week to assess for interval displacement
    • immediate bedside closed reduction
      • indications
        • poorly perfused hand 
      • technique
        • gentle traction and elbow flexion to 20-40 degrees
          • this often restores perfusion 
        • if perfusion not restored
          • take to OR for CRPP in an urgent or emergent manner (see below)
        • if perfusion is restored
          • take to OR in an urgent manner
  • Operative
    • closed reduction and percutanous pinning (CRPP)      
      • indications 
        • fracture pattern
          • type II and III supracondylar fractures
          • flexion type
          • medial column collapse
      • time to CRPP dictated by neurovascular status
        • non-urgent (can wait overnight)
          • indications
            • warm perfused hand without neuro deficits
              • some argue can treat an isolated AIN injury in non-urgent fashion
          • technique
            • splint in 30-40° elbow flexion, admit overnight for observation and elevation for elective surgery
        • urgent  (same day - do not wait overnight)
          • indications
            • pulseless, well-perfused hand
            • sensory nerve deficits
            • excessive swelling
            • "brachialis sign" 
              • ecchymosis, dimpling/puckering antecubital fossa, palpable subcutaneous bone fragment
                • indicates proximal fragment buttonholed through brachialis 
              • implies more serious injury, higher likelihood of arterial injury, significant swelling, more difficult closed reduction
            • "floating elbow"
              • ipsilateral supracondylar humerus and forearm/wrist fractures warrant timely pinning of both fractures to decrease the risk of compartment syndrome 
          • technique
            • check vascular status after reduction
              • if evidence of good distal perfusion admit for 48 hours of observation 
              • if not well perfused perform vascular exploration
        • emergent (within hours)
          • indications
            • pulseless, poorly perfused hand  
          • technique
            • check vascular status after reduction
              • if well perfused admit and observe for 48 hours
              • if not well perfused perform vascular exploration
    • emergent vascular exploration and CRPP
      • indications
        • pulseless white hand (pale, cool, no doppler) following CRPP
        • pulsatile and perfused hand that loses pulse following CRPP
      • technique
        • remove K-wires and reassess vascular status
        • open exploration and reduction if vascular status does not improve
    • open reduction, percutaneous pinning, +/- vascular exploration
      • indications
        • open fracture
        • failed closed reduction 
          • more frequently required with flexion type fractures (compared to extension type)
        • pulseless white OR pink hand that is unable to be reduced or there remains a gap
          • gap might represent entrapped vascular structure
Techniques
  • Closed reduction and percutaneous pinning (CRPP) post
    • fixation
      • closed reduction (extension-type)
        • posteromedial displacement: forearm pronated with hyperflexion
        • posterolateral displacement: forearm supinated with hyperflexion 
        • if pronation or supination does not work, try the opposite
      • 2 lateral pins  
        • usually sufficient in type II fractures
        • test stability under fluoroscopy
        • technical pearls
          • maximize separation of pins at fracture site  
          • engage both medial & lateral columns proximal to fracture
          • engage sufficient bone in proximal & distal segments
          • low threshold for 3rd lateral pin if concern about stability with first 2 pins
      • 3 lateral pins  
        • biomechanically stronger in bending and torsion than 2-pin constructs
        • indications (where 2 lateral pins are insufficient)
          • comminution
          • type III and type IV (free floating distal fragment)
        • no significant difference in stability between three lateral pins and crossed pins
          • risk of iatrogenic nerve injury from a medial pin makes three lateral pins the construct of choice
      • crossed pins
        • biomechanically strongest to torsional stress 
        • higher risk of ulnar nerve injury (3-8%)  
          • highest risk if placed with elbow in hyperflexion as ulnar nerve subluxates anteriorly over medial epicondyle in some children
        • reduce the risk of ulnar nerve injury by
          • placing medial pin with elbow in extension
          • use small medial incision (rather than percutaneous pinning)
      • remove pins postop at 3 weeks 
  • Open Reduction with Percutaneous Pinning
    • approach
      • anterior approach if pulseless or median nerve injury
      • a lateral or medial approach where periosteum is torn
      • never posterior as posterior dissection can --> AVN
    • soft tissue
      • identify median nerve and brachial artery
    • bone work
      • confirm reduction with C-arm
    • instrumentation
      • 2 or 3 K-wires depending on the degree of stability
Complications
  • Pin migration
    • most common complication (~2%)
  • Infection
    • occurs in 1-2.4%
    • typically superficial and treated with oral antibiotics
  • Cubitus valgus
    • caused by fracture malunion
    • can lead to tardy ulnar nerve palsy
  • Cubitus varus (gunstock deformity) 
    • caused by fracture varus malunion, especially in medial comminution pattern 
    • is NOT caused by growth disturbance
    • usually a cosmetic issue with little functional limitations, but may be present  
  • Recurvatum
    • common with non-operative treatment of Type II and Type III fractures
  • Nerve palsy from injury 
    • usually resolve, nerves rarely torn
    • extension type fractures 
      • neuropraxia in 11%
      • most commonly AIN 
      • mechanism = tenting of nerve on fracture, or entrapment in the fracture site
    • flexion type fractures 
      • neuropraxia in 17%
      • most commonly cause ulnar neuropraxia 
  • Vascular Injury
    • radial pulse absent on initial presentation in 7-12%
    • pulseless hand after closed reduction and pinning (3-4%)    
    • decision to explore is based on quality of extremity perfusion rather than absence of pulse
    • arteriography is NOT indicated in isolated injuries
    • role of doppler is unclear and does not change treatment
  • Volkmann ischemic contracture
    • rare, but dreaded complication
    • may result from elbow hyperflexion casting
      • increase in deep volar forearm compartment pressures and loss of radial pulse with elbow flexed >90°
    • rarely seen with CRPP and postoperative immobilization in less than 90°
  • Postoperative stiffness
    • rare after casting or after pinning procedures
      • remove pins and allow gentle ROM at 3-4 weeks postop 
    • resolves by 6 months 
    • literature does not support the use of physical therapy