21.1 Pediatric Orthopedic Emergencies: Salter-Harris Fractures, Compartment Syndrome & Rhabdomyolysis

Pediatric Orthopedic Emergencies: Salter–Harris Fractures, Compartment Syndrome & Rhabdomyolysis

Quick Answer: Localize the fracture and document distal nerve function and perfusion before and after immobilization or reduction. Give prompt IV antibiotics for suspected open fractures and assess tetanus prophylaxis. Keep suspected SCFE strictly non-weight-bearing. When a casted child develops findings concerning for compartment syndrome, release every constricting layer and obtain emergency orthopedic assessment. In crush-associated rhabdomyolysis, treat perfusion and potassium problems while tracking urine output and fluid tolerance.

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Pediatric Fracture Patterns and Growth Plates

A child's pliable bone and relatively thick periosteum allow characteristic incomplete injuries. A buckle fracture is a compression injury with cortical bulging and no break through the opposite cortex. An isolated distal radius buckle fracture can usually be treated with a removable splint. A greenstick fracture breaks the convex cortex while the opposite cortex bends. Plastic deformation produces abnormal bowing without a discrete fracture line. Greenstick injuries and bowing require assessment of alignment, adjacent joints and any associated fracture before choosing reduction or immobilization.

Remodeling depends on age, growth remaining, distance from an active physis and direction of deformity. Angulation in the plane of motion near an active physis has greater potential to remodel. Rotational malalignment, displaced joint surfaces and coronal deformity at the distal humerus should not be expected to correct with growth. Pediatric fracture definitions · Pediatric remodeling guidance

Consider inflicted injury when the mechanism or developmental stage does not fit the injury. Fractures in nonambulatory children, classic metaphyseal lesions, posteromedial rib fractures and scapular or sternal fractures warrant particular attention. Interpret the pattern alongside the history, examination and alternative causes of bone fragility. AAP clinical report on childhood fractures and abuse

Salter–Harris Classification

Use injury-specific reduction limits. For example, for Tillaux and triplane ankle fractures, a pediatric ED pathway uses less than 2 mm displacement to consider nonoperative care and more than 2 mm to prompt orthopedic evaluation for operative treatment. The orthopedic team can use CT to define displacement and plan treatment. This is a site-specific example. Displaced, intra-articular or higher-risk physeal injuries need prompt orthopedic input and appropriately timed growth surveillance. Pediatric physeal injury guidance · Distal tibial physeal fracture pathway

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High-Risk Pediatric Orthopedic Emergencies

Supracondylar Humerus Fractures

Extension injuries commonly follow a fall onto an outstretched hand. On a true lateral radiograph, assess the anterior humeral line relative to the capitellum and look for a posterior fat pad as an occult fracture clue. In the Gartland classification, type I is nondisplaced, type II is angulated with posterior cortical contact, and type III is completely displaced. Type I commonly requires above-elbow immobilization. Displaced injuries need orthopedic evaluation. Type III generally needs reduction and percutaneous pinning. For type II, alignment and stability guide whether pinning is needed.

• Nerve exam: Test median/anterior interosseous, radial and ulnar function. A weak circle when making the OK sign suggests anterior interosseous motor dysfunction if the child can participate. This nerve flexes the thumb interphalangeal joint via flexor pollicis longus and the index distal interphalangeal joint via flexor digitorum profundus. Test radial motor function with extension and ulnar motor function with finger abduction, and assess sensory territories separately.
• Perfusion exam: Record pulse, capillary refill, color and temperature. A pink pulseless hand needs urgent reduction and fixation with repeat pulse, perfusion and Doppler assessment. A cool, pale and poorly perfused hand needs emergency reduction and stabilization. Persistent ischemia after reduction requires urgent vascular evaluation and possible exploration. A persistently pulseless but perfused hand still needs close monitoring and an orthopedic plan informed by Doppler findings and associated nerve injury. Do not delay reduction of a threatened limb for routine angiography.
• Consequence of missed ischemia: Brachial artery compromise or forearm compartment syndrome can lead to fixed ischemic flexion contracture (Volkmann contracture). AAOS pediatric supracondylar guidance · AAOS vascular-injury criteria · Pediatric ED assessment

Suspected Open Fracture

A wound communicating with a fracture can be small or distant from the obvious deformity. The Gustilo–Anderson scheme describes type I as a small clean wound with limited injury, type II as a larger wound without extensive tissue damage, and type III as a severe or high-energy injury. Type IIIA has enough coverage after debridement, type IIIB needs additional soft-tissue coverage, and type IIIC includes an arterial injury requiring repair. The operative team determines final grade using the extent of injury and contamination as well as wound size.

1. Give IV antibiotics promptly. CHOP's pediatric pathway targets administration within an hour of ED arrival. Cefazolin is a common choice for less severe injuries. Use the pediatric trauma protocol for severe injuries, unusual water or soil contamination and significant antibiotic allergies. Institutions differ in their type III regimens.
2. Cover with a sterile dressing, splint, document distal neurovascular findings and involve orthopedics promptly for wound and fracture management. Address hemorrhage or ischemia immediately. Let the injury and surgical plan determine the timing and location of irrigation and debridement.
3. Treat an open fracture as a dirty or major wound for tetanus prevention. Give an age-appropriate vaccine if the series is incomplete or unknown, or if the last dose was at least five years ago after a completed series. Add TIG for unknown, absent or incomplete vaccination, or HIV or severe immunodeficiency. CHOP pediatric open fracture pathway · US pediatric trauma center practice study · CDC wound prophylaxis

Slipped Capital Femoral Epiphysis and Perthes Disease

SCFE often presents around puberty with a limp and hip, groin, thigh or referred knee pain. Loss of internal rotation and obligatory external rotation during passive hip flexion are clues. Obesity is a common risk factor. An unusually young or small child warrants consideration of an endocrine or metabolic association. A stable slip permits ambulation with or without crutches by history. Once suspected, keep the patient strictly non-weight-bearing and obtain urgent orthopedics. Use AP pelvis and a frog-leg lateral for a stable presentation. If the child was unable to ambulate even with support and an unstable slip is suspected, obtain a cross-table lateral to avoid hip manipulation. On the AP film, Klein's line may no longer cross the epiphysis. A normal-appearing line can miss a subtle slip. Stable slips are commonly treated with in situ screw fixation. Orthopedics determines the operative plan for unstable slips.

Legg–Calvé–Perthes disease is idiopathic ischemia of the femoral head in childhood. A younger child with a gradual limp and restricted hip abduction and internal rotation warrants hip evaluation. Radiographs can show sclerosis, fragmentation or flattening as disease evolves. Arrange orthopedic follow-up. A febrile child with acute painful limitation needs urgent evaluation for infection. POSNA SCFE guidance · POSNA Perthes guidance

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Acute Extremity Compartment Syndrome

Rising pressure inside a closed fascial compartment reduces tissue perfusion and can cause irreversible muscle and nerve injury. Watch closely after displaced tibial and forearm fractures, high-energy crush injuries and tight immobilization. Increasing analgesic requirements, anxiety and agitation are useful warning signs in children. Look for escalating pain and pain on passive stretch. Distal pulses can remain palpable. Waiting for pallor, paralysis or loss of pulse delays recognition.

Pressure measurement can support an equivocal or unreliable examination. Measure the relevant compartments with concurrent blood pressure and interpret the results with the clinical course and orthopedic assessment. Subtract the measured compartment pressure from the diastolic pressure to obtain the delta pressure. A small gradient is concerning in context. A single absolute pressure over 30 mmHg or delta pressure at or below 30 mmHg does not by itself establish the diagnosis in a child. Pediatric lower-leg pressure studies found higher resting pressures than adult values and low gradients without clinical compartment syndrome.

Pediatric orthopedic compartment syndrome guidance · Pediatric lower-leg pressure study · BOA emergency compartment syndrome standard

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Rhabdomyolysis and Acute Kidney Injury

Muscle injury releases creatine kinase (CK), myoglobin, potassium and phosphate. Consider rhabdomyolysis after crush injury, prolonged immobilization or seizures, as well as in viral myositis, exertion and selected metabolic conditions. CK above five times the upper reference limit or above 1,000 U/L is a commonly used laboratory definition in the appropriate clinical setting. A heme-positive dipstick with few or no red cells supports pigmenturia. Myoglobin is likely with muscle injury, but dipstick alone does not identify the pigment. Use serial CK and assess creatinine, electrolytes, urine output and perfusion. The CK value alone cannot determine AKI risk or the need for dialysis.

Urine-output targets vary by population and protocol. For example, a nontraumatic pediatric pathway uses an average of 1–2 mL/kg/hour and specifies 200 mL/hour as an IV infusion cap. Its population excludes trauma and burns. In major crush injury, use the trauma and nephrology team's goal and reassess as kidney function changes. Connecticut Children's rhabdomyolysis pathway · AAST rhabdomyolysis consensus · Pediatric hyperkalemia pathway