summary Supracondylar Fractures are one of the most common traumatic fractures seen in children and most commonly occur in children 5-7 years of age from a fall on an outstretched hand. Diagnosis can be made with plain radiographs. Treatment is usually closed reduction and percutanous pinning (CRPP), with the urgency depending on presence or absence of hand perfusion. Epidemiology Incidence extension type most common (95-98%) flexion type less common (<5%) Demographics occur most commonly in children aged 5-7years M = F Etiology 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) +/- one year, varies between boys and girl Ossification Centers of the Elbow Ossification Center Years at ossification (appear on xray) Years at fusion (appear on xray) Capitellum 1 12 Radial Head 4 15 Medial epicondyle 6 17 Trochlea 8 12 Olecranon 10 15 Lateral epicondyle 12 12 Classification Gartland Classification (may be extension or flexion type) Characteristics Treatment Type I Nondisplaced Beware of subtle medial comminution leading to cubitus varus which technically means it is not a Type I Fracture Treated with cast immobilization x 3-4wks, with radiographs at 1 week Type II Displaced, in 1 plane Posterior cortex and posterior periosteal hinge intact Deformity is in the sagittal plane only Typically treated with CRPP Type III Displaced, 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 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 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 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 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) 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 pins should be inserted with elbow in flexion for extension-type injury and elbow in extension for flexion-type injury 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% increased risk in age <4.5 years 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 may represent a cosmetic issue with little functional limitations, however has been associated with posterolateral elbow instability can lead to tardy ulnar nerve palsy anterior nerve subluxation is most common cause nerve entrapment by scar tissue and fibrous bands of FCU second most common cause 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%) if perfusion is lost following reduction and pinning, pins should be removed immediately 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