Pediatric Orthopedics Flashcards
Why do kids gets certain fractures?
■ thicker, more active periosteum results in pediatric-specific fractures: greenstick (one cortex), torus (i.e. ‘buckle’, impacted cortex) and plastic (bowing)
adults fracture through both cortices
Most common fractures in children
distal radius fracture most common in children (phalanges second), the majority are treated with closed reduction and casting
Epiphyseal growth plate
■ weaker part of bone, susceptible to fractures
■ plate often mistaken for fracture on x-ray and vice versa (X-ray opposite limb for comparison), especially in elbow
■ tensile strength of bone < ligaments in children, therefore clinician must be confident that fracture and/or growth plate injury have been ruled out before diagnosing a sprain
■ intra-articular fractures have worse consequences in children because they usually involve the growth plate
Role of anatomic reduction in children
■ gold standard with adults
■ may cause limb length discrepancy in children (overgrowth)
■ accept greater angular deformity in children (remodelling minimizes deformity)
Greenstick fractures are easy to reduce but can redisplace while in cast due to intact periosteum
When should you have a higher suspicion of child abuse
■ high index of suspicion with fractures in non-ambulating children (<1 yr); look for other signs, including X-ray evidence of healing fractures at different sites and different stages of healing
■ common suspicious fractures in children: metaphyseal corner fracture (hallmark of non-accidental trauma), femur fracture < 1 yo, humeral shaft < 3 yo, sternal fractures, posterior rib fractures, spinous process fractures
Stress fracture mechanism
• insufficiency fracture
■ stress applied to a weak or structurally deficien bone
• fatigue fracture
■ repetitive, excessive force applied to normal bone
• most common in adolescent athletes
Stress fracture most common site
tibia
Stress fracture diagnosis
- localized pain and tenderness over the involved bone
- plain films may not show fracture for 2 wk
- bone scan positive in 12-15 d
Stress fracture treatment
rest (can take several months)
Epiphyseal injury classification
Salter-Harris
Salter-Harris I description and treatment
Straight through; stable
Transverse through growth plate
Closed reduction and cast immobilization (except SCFE – ORIF); heals well, 95% do not affect growth
Salter-Harris II description and treatment
Above
Through metaphysis and along growth plate
Closed reduction and cast if anatomic; otherwise ORIF
Salter-Harris III description and treatment
Low
Through epiphysis to plate and along growth plate
Anatomic reduction by ORIF to prevent growth arrest, avoid fixation across growth plate
Salter-Harris IV description and treatment
Through and through
Through epiphysis and metaphysis
Closed reduction and cast if anatomic; otherwise ORIF
Salter-Harris V description and treatment
Ram
Crush injury of growth plate
High incidence of growth arrest; no specific treatment
What Salter Harris types are more likely to cause growth arrest and progressive deformity
III-V
Slipped Capital Femoral Epiphysis definition and risk factors
- type I Salter-Harris epiphyseal injury at proximal hip
- most common adolescent hip disorder, peak incidence at pubertal growth spurt risk factors: male, obese (#1 factor), hypothyroid (risk of bilateral involvement)
Slipped Capital Femoral Epiphysis etiology
• multifactorial
■ genetic: autosomal dominant, black children at highest risk
■ cartilaginous physis hypertrophies too rapidly under growth hormone effects
■ sex hormone secretion, which stabilizes physis, has not yet begun
■ overweight: mechanical stress
■ trauma: causes acute slip
Slipped Capital Femoral Epiphysis clinical features
• acute: sudden, severe pain with limp
• chronic (typically): groin and anterior thigh pain, may present with knee pain
■ positive Trendelenburg sign on affected side, due to weakened gluteal muscles
• tender over joint capsule
• restricted internal rotation, abduction, flexion
■ Whitman’s sign: obligatory external rotation during passive flexion of hip
• Loder classification: stable vs. unstable (provides prognostic information)
■ unstable means patient cannot ambulate even with crutches
Slipped Capital Femoral Epiphysis investigations
• X-ray: AP, frog-leg, lateral radiographs both hips
■ posterior and medial slip of epiphysis
■ disruption of Klein’s line
■ AP view may be normal or show widened/lucent growth plate compared with opposite side
Slipped Capital Femoral Epiphysis treatment
• operative
■ mild/moderate slip: stabilize physis with pins in current position
■ severe slip: ORIF or pin physis without reduction and osteotomy after epiphyseal fusion
Slipped Capital Femoral Epiphysis complications
• AVN (roughly half of unstable hips), chondrolysis (loss of articular cartilage, resulting in narrowing of joint space), pin penetration, premature OA, loss of ROM
What is Klein’s Line
On AP view, line drawn along supero-lateral border of femoral neck should cross at least a portion of the femoral epiphysis. If it does not, suspect SCFE
Developmental Dysplasia of the Hip definition
- abnormal development of hip, resulting in dysplasia and subluxation/dislocation of hip
- most common orthopedic disorder in newborns