Chapter 7 Pediatric orthopedic emergencies
Orthopedic Emergencies, ed. Michael C. Bond, Andrew D. Perron, and Michael K. Abraham. Published by Cambridge University Press. © Cambridge University Press 2013.
Key facts
Pediatric bones are more flexible than adults, leading to unique fracture patterns such as:
Because of the high metabolic turnover for pediatric bones, closed reduction and casting is the treatment of choice for most pediatric fractures
Transient synovitis is an inflammation of the hip joint that typically follows a viral upper respiratory infection (URI) and is characterized by hip pain and a limp
Transient synovitis is typically self-limited and treated with non-steroidal anti-inflammatory medication (NSAIDs), though excluding a bacterial infection is critical to avoid significant morbidity
Slipped capital femoral epiphysis (SCFE) occurs in obese pre-pubescent children. Pain may be indolent in cases of chronic SCFE, though acute worsening of pain is seen after relatively minor trauma in some cases
SCFE presents bilaterally in a significant proportion of cases, even if only one side is symptomatic
Unique features of pediatric fractures
General principles
Bones in children remodel at a more rapid rate than adults, making closed reduction a viable treatment modality for many fractures that would require operative repair in adults
Bones in children are more flexible, leading to unique fracture patterns such as buckle and greenstick fractures that are not seen in adults
Injury to growth plates can result in significant morbidity
Buckle fractures
Buckle or torus fractures typically occur at the metaphyseal diaphyseal junction and result from a “crumpling” of the more porous metaphysis (see Figure 7.1)
Typical locations for buckle fractures include the distal radius, distal tibia, distal fibula and distal femur
A fall on to an outstretched arm or leg is a common mechanism of injury
Treatment involves splinting or casting for 4 weeks and outpatient orthopedic follow-up. Some centers will immobilize for even shorter periods with similar results
Prognosis is excellent
Pearl: Buckle fractures can be adequately treated with splinting or casting for 4 weeks with excellent prognosis.
Greenstick fractures
Greenstick fractures commonly occur after a fall on to an outstretched arm or jumping on to a leg (see Figure 7.2)
Because of the flexibility of pediatric bones, one cortex breaks while the other remains intact, similar to trying to break a piece of green wood
Treatment of greenstick fractures involves closed reduction and splinting or casting
Prognosis is excellent, provided acceptable closed reduction is achieved
Plastic deformation
Occurs after a longitudinal force is applied to growing bone, such as the force that occurs with a fall onto an outstretched arm
The bone bends and microscopic fractures occur which result in a bend but no visible fracture line on plain radiographs
Typically occurs in the radius, ulna or fibula
If the deformity is less than 20°, the bone often remodels and closed reduction is not needed
Greater degrees of deformity require attempts at closed reduction
Casting is the treatment of choice and these injuries rarely need operative repair
Growth plate injury
Key facts
The Salter–Harris classification system is used to describe fractures involving the growth plate. The higher the classification, the higher the likelihood that the patient will have growth abnormalities such as growth arrest, malunion, growth disturbance with angulation, or growth acceleration
Growth plate injuries account for 20% of all pediatric fractures
Pearl: Salter–Harris Type I and V injuries can appear the same on plain radiographs. Comparison views of the contralateral leg can help distinguish the two, though the provider should always assume it is the more serious (Type V) injury.
Description
Injury to the growth physis or physeal plate
The most commonly affected bones are the long bones of growing children specifically distal radius, distal tibia, phalanges, and proximal humerus
Sites which show the most growth disturbance when injured are the distal femur and distal tibia
Epidemiology
Younger children have a higher risk of serious sequela from a physeal injury because they have more potential growth remaining
Incidence
Males are affected twice as often as females
Accounts for 20% of all pediatric fractures
Prevalence
Occurs most frequently in girls aged 11–12 years and boys aged 12–14 years, when growth is most rapid
Etiology
Trauma, infection, tumors, drugs (steroids, testosterone, estrogen)
Salter–Harris classification
Five total patterns of physis fractures. Types III to V are at highest risk for growth plate damage
Type I: Split parallel through the physis
Type II: Split through physis and exits through the metaphysis
Type III: Intra-articular fracture through the epiphysis and exits through physis
Type IV: Intra-articular fracture through the epiphysis that exits through metaphysis and physis
Type V: Crush injury to the physis
Physical examination
Evaluate the limb for open wounds, swelling, crepitus, and neurovascular status
Tests
Plain radiographs: AP, lateral, and oblique
CT scan: May be necessary to evaluate complicated fracture patterns
MRI: Best method to establish injury to the growth plate since it can visualize the cartilage of the growth plate as separate and distinct from bone
Treatment
Ice, immobilization
Pain medication
Monitor for compartment syndrome as appropriate
Splint non-displaced fractures
Displaced fractures should be reduced under procedural sedation, hematoma block, or general anesthesia. The fracture is then splinted and alignment is rechecked with repeat plain radiographs
Follow-up
Patients should be seen by orthopedics in 3 to 5 days, and the splint is usually maintained for 1–2 weeks, until swelling has resolved
Surgery
If closed reduction is not possible or fractures become unstable, the fracture will need to be reduced in the operating room and stabilized by percutaneous pins or internal hardware
Prognosis
The higher Salter–Harris classification correlates with higher incidence of growth abnormality such as growth arrest, malunion, growth disturbance with angulation, or growth acceleration. The closer the child is to skeletal maturity, the less likely growth abnormality will result
A bony bar can be resected or a corrective osteotomy done surgically to restore angulation or length deformity. Another simple option is to stop the growth in the contralateral growth plate to maintain symmetry
Osgood–Schlatter disease
Key facts
A traction apophysitis of the tibial tuberosity
Treatment is supportive with rest, ice, pain control, and patellar strap
Description
Osgood–Schlatter disease is a traction apophysitis of the tibial tuberosity caused by repetitive strain by the quadriceps tendon.
Epidemiology
Incidence
Males are affected twice as often as females
Bilateral presentations are seen in 25–50% of patients
Commonly seen in patients who participate in running, jumping, and squatting activities
Prevalence
Frequent in girls aged 8–12 years and boys aged 10–15 years when growth is most rapid
Etiology
Repetitive traction of the patellar tendon from the tibia tubercle from running, jumping, rapid growth, and overuse
Intrinsic risk factors
Tight rectus femoris, tight hamstrings, patella alta, and external tibial rotation
Physical examination
May note tenderness to palpation directly over the tibial tuberosity with no or trace swelling at the insertion site
Testing of the quadriceps muscle will elicit full strength but will cause pain at the site. If strength of resisted leg extension is weak and there is swelling at the tibial tuberosity, consider that there may be a tibial tubercle avulsion fracture
Deep squats will elicit pain
Evaluate foot alignment for pathology which may stress the knee such as over-pronation or pes planus
Tests
Radiographs are not required. If radiographs are done, the lateral knee view may demonstrate sclerosis at the tubercle
Treatment
Rest or activity modification
Ice
Possible short course of anti-inflammatory medication
Eccentric stretching and strengthening the quadriceps and hamstrings
Patellar strap bracing
Foot inserts if indicated by clinical examination
Follow-up
Follow-up with primary care physician if pain progresses, limp, swelling develops or inability to walk
Prognosis
Favorable, but will be exacerbated during times of rapid growth or activity
Many will have prominence of the tibial tuberosity into adulthood. May have persistent pain with kneeling as an adult, which may represent presence of residual ossicles and warrant surgical removal
Pearl: If initial presentation includes swelling, inability to actively extend the knee, decreased strength with knee extension, inability to walk, obtain radiograph to evaluate for avulsion fraction of the tibial epiphysis.