Top 10 Pediatric Orthopaedics Questions - KNRUHS Theory Final Exam

1. Supracondylar Fracture of Humerus in Children

• Gartland classification (Type I, II, III) - and Type IV (added later)
• Extension type (98%) vs flexion type
• Neurovascular assessment - anterior interosseous nerve (most common nerve injury), radial nerve, brachial artery
• Management: Type I - cast; Type II - closed reduction + cast or percutaneous K-wires; Type III - CRPP (closed reduction percutaneous pinning) or ORIF
• Surgical emergency if pulseless hand (non-perfused limb = immediate surgery to prevent Volkmann ischemic contracture)
• Compartment syndrome in 0.1-0.3%
• Complications: Volkmann ischemic contracture, cubitus varus (gunstock deformity - most common late complication), malunion
• K-wire configuration: lateral-only (safer, avoids ulnar nerve) vs cross-pinning

2. Developmental Dysplasia of Hip (DDH)

• Risk factors: female, first-born, breech, positive family history, oligohydramnios
• Pathology: shallow acetabulum, lax capsule, anteverted femoral neck
• Ortolani sign (reduces dislocated hip) vs Barlow sign (provokes dislocation)
• Imaging: Ultrasound (Graf classification) < 6 months; X-ray (Hilgenreiner, Perkins lines, Shenton's arc) > 6 months
• Acetabular index (normal <30°), CE angle
• Treatment by age: 0-6 months = Pavlik harness (first-line); 6-18 months = closed/open reduction + spica cast; 18 months-8 years = open reduction + Salter innominate osteotomy; >8 years = Chiari/shelf osteotomy
• Complications: avascular necrosis of femoral head (most feared)

3. Perthes Disease (Legg-Calvé-Perthes Disease)

• Age: 4-8 years, boys >> girls (4:1), bilateral in 10-15%
• Etiology: idiopathic AVN of femoral epiphysis
• Catterall classification (Groups I-IV by extent of head involvement) and Herring lateral pillar classification (A, B, B/C, C) - more prognostically relevant
• Waldenstrom stages: initial (dense/necrotic), fragmentation, reossification (healing), residual deformity
• Clinical: painless limp, Trendelenburg gait, restricted abduction/internal rotation
• MRI is the earliest investigation
• Principle of containment - keep femoral head within acetabulum during healing
• Treatment: Age <6 = observation/physiotherapy; Age 6-8 = conservative containment (abduction brace/Petrie cast); Age >8 with lateral pillar B/C or C = femoral varus osteotomy or Salter innominate osteotomy
• Prognosis: Spherical head at skeletal maturity = good prognosis (Mose method)

4. Slipped Capital Femoral Epiphysis (SCFE)

• Age: 10-16 years; obese males (typical), or tall thin adolescent growth spurt
• Always check the contralateral hip (20-40% bilateral)
• X-ray: Klein's line (line along superior femoral neck should intersect the epiphysis - it misses in SCFE); Steel sign (crescent of metaphysis overlapping ischium)
• Southwick angle to grade severity: Mild <30°, Moderate 30-60°, Severe >60°
• Stable (can bear weight) vs Unstable (cannot bear weight - ~50% AVN risk)
• Treatment: In situ fixation with single central screw - standard of care regardless of severity
• Unstable SCFE = surgical emergency (fix within 24 hours)
• Modified Dunn procedure for severe/unstable SCFE (better anatomy but higher AVN risk)
• Complications: AVN (most feared), chondrolysis

5. Congenital Talipes Equinovarus (CTEV / Clubfoot)

• Deformities (CAVE mnemonic): Cavus (high arch), Adductus (forefoot adduction), Varus (heel varus), Equinus (plantarflexion) - corrected in this order
• Incidence 1-2/1000, male > female, bilateral 50%
• Pirani score and Dimeglio score for severity
• Ponseti method (gold standard): serial casting (5-7 casts over 6-8 weeks) + Achilles tenotomy (~80% need it) + Dennis-Browne boots and bar for 4-5 years
• French functional method (Lyon method) - physiotherapy alternative
• Surgical: Posteromedial release (Cincinnati incision) - for failed conservative treatment; now rarely needed with Ponseti
• Relapse is common - retreatment with casting or tibialis anterior tendon transfer (lateral transfer for dynamic supination)
• vs. Positional talipes (flexible, corrects with gentle pressure - no treatment needed)

6. Pediatric Septic Arthritis and Acute Hematogenous Osteomyelitis

• Osteomyelitis: metaphysis most affected (rich sinusoidal vasculature, sluggish flow, absence of phagocytes)
• Kocher criteria for septic arthritis of hip: fever, non-weight-bearing, ESR >40, WBC >12,000 - 4 criteria = 99% probability
• Causative organisms: Neonates - Group B Streptococcus, S. aureus; 1 month-5 years - S. aureus, H. influenzae (vaccinated = rare); Adolescents - S. aureus; Sickle cell - Salmonella
• Tom Smith arthritis (septic arthritis hip in infants) - destroys the femoral head, leads to pathological dislocation
• Investigation: MRI (investigation of choice), USS (for effusion/guided aspiration), bone scan
• Kocher-Loder criteria algorithm
• Treatment: IV antibiotics (Flucloxacillin + Gentamicin); Surgical drainage if no improvement in 48 hours or abscess present
• Chronic osteomyelitis: sequestrum (dead bone) + involucrum (new periosteal bone) + cloaca (sinus tract)

7. Idiopathic Scoliosis (Adolescent Idiopathic Scoliosis - AIS)

• Cobb angle measurement (angle between end vertebrae)
• Risser sign (skeletal maturity, 0-5) - key for predicting progression and treatment
• Right thoracic curve most common in AIS
• King-Moe classification (older) vs Lenke classification (current standard, 6 types)
• Treatment: <25° = observation (monitor every 6 months); 25-40° = Milwaukee brace or TLSO (Boston brace) - effective only if Risser 0-2 (still growing); >40-50° = surgery (posterior spinal fusion + instrumentation)
• Surgical: Harrington rods (historical), now pedicle screw constructs + rod correction
• Neuromuscular vs idiopathic distinction
• Adam's forward bend test, scoliometer

8. Salter-Harris Classification of Physeal Injuries

• Type I: Transverse through physis (SLIPPED) - good prognosis
• Type II: Through physis + metaphysis (ABOVE - most common, 75%) - Thurston-Holland fragment
• Type III: Through physis + epiphysis (LOWER) - intra-articular, ORIF needed
• Type IV: Through metaphysis + physis + epiphysis (THROUGH) - intra-articular, must achieve anatomic reduction
• Type V: Crush/compression of physis (RAMMED) - worst prognosis, growth arrest
• Peterson Type VI (later addition): periosteal injury
• Complications: premature physeal closure, angular deformity, limb length discrepancy
• Mnemonic: SALTR (Slipped, Above, Lower, Through, Rammed)

9. Cerebral Palsy - Orthopaedic Management

• Upper motor neuron disorder, non-progressive but permanent
• Spastic type (most common, 70-80%) - unilateral (hemiplegia), bilateral (diplegia - Little's disease, most common), quadriplegia
• GMFCS (Gross Motor Function Classification System) I-V
• Common deformities: equinus foot (most common - Achilles tightening), hip subluxation/dislocation (spastic diplegia), scissoring gait, crouch gait
• Gait analysis: gold standard for pre-surgical planning
• SEMLS (Single Event Multilevel Surgery) - superior to staged procedures for ambulatory CP
• Spasticity management: physiotherapy, oral Baclofen, Botulinum toxin (temporary, 3-6 months), intrathecal Baclofen pump, selective dorsal rhizotomy
• Hip surveillance protocol (annual x-rays for migration percentage)
• Surgical options: soft tissue (muscle lengthening, tendon transfer) vs bony procedures (derotation osteotomy)

10. Limb Length Discrepancy (LLD)

• Assessment: Galeazzi sign, measurement by blocks, scanography (most accurate), CT scanogram
• Growth prediction methods: Moseley straight line graph, Green-Anderson tables, multiplier method (most modern)
• Causes: post-traumatic (physeal arrest), DDH, hemihypertrophy, polio, Perthes
• Treatment thresholds: <2 cm = shoe raise; 2-5 cm = epiphysiodesis (permanent), shoe raise or lengthening; >5 cm = limb lengthening (Ilizarov method / distraction osteogenesis)
• Epiphysiodesis timing: must be done before physis closes; Bowen/Moseley method to time
• Ilizarov principle: gradual distraction at 1 mm/day in 0.25 mm increments x4 daily
• Complications of limb lengthening: pin tract infection, joint contracture, premature consolidation, non-union

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Next 10 Pediatric Orthopaedics Questions - "Safe Side" List

11. Tibia Vara (Blount Disease)

• Pathological genu varum - failure of medial proximal tibial physis (zone of hypertrophy)
• Infantile (0-3 yrs, bilateral, obese) vs Late-onset (adolescent, unilateral, obese)
• Langenskiold classification (Stages I-VI for infantile) - Stage IV+ requires surgery
• X-ray: metaphyseal-diaphyseal angle (Drennan angle) >11° is pathological; fragmentation and beaking of medial tibial metaphysis
• Differential diagnosis: physiologic bowing (improves by 2 years, no beak, symmetrical), rickets (cupping/fraying of metaphysis)
• Treatment: <3 years (infantile) = KAFO brace (knee-ankle-foot orthosis) if caught early; >3 years or Stage III+ = proximal tibial valgus osteotomy; adolescent = corrective osteotomy or hemi-epiphysiodesis (guided growth with 8-plate)
• Ilizarov method for severe/complex cases

12. Lateral Condyle Fracture of Humerus in Children

• Age 5-10 years, Salter-Harris Type IV fracture
• Jakob classification (3 types based on displacement): Stage I (<2 mm), Stage II (2 mm, fragment hinge on lateral cortex), Stage III (complete displacement + rotation)
• The fracture is intra-articular - articular cartilage holds fragments even when bone looks minimally displaced on X-ray
• Arthrogram is gold standard to assess articular disruption
• Management: <2 mm displacement = cast immobilization + serial X-rays; >2 mm = ORIF with K-wires or screws
• Complications: Non-union is the most dreaded (due to synovial fluid bathing the fracture site) - leads to cubitus valgus + tardy ulnar nerve palsy (delayed ulnar nerve palsy years later)
• Also know: medial epicondyle fracture (look for incarcerated fragment in elbow joint)

13. Congenital Pseudarthrosis of Tibia (CPT)

• Anterolateral bowing of tibia - pathognomonic presentation
• Associated with Neurofibromatosis Type 1 (NF-1) in 50-60% of cases
• Crawford/Boyd classification (Types I-IV): Type I = anterolateral bowing with no fracture; Type II = bowing with cortical thickening/sclerosis; Type III = cyst formation; Type IV = frank pseudarthrosis
• Management: prophylactic splinting/bracing in pre-fracture stages; once fracture occurs = surgery required
• Surgical options: intramedullary rodding (Williams rod), Ilizarov fixator, vascularized fibular graft (best results for established pseudarthrosis), BMP (bone morphogenic protein) adjunct
• Prognosis is poor - multiple surgeries often needed; amputation considered if 3+ failed surgeries
• Unlike clavicle pseudarthrosis - union is NOT predictable

14. Osteochondroses - Osgood-Schlatter & Osteochondritis Dissecans

• Traction apophysitis of tibial tubercle (patellar tendon insertion)
• Adolescent males, active/athletic, bilateral in 20-30%
• Pain and swelling over tibial tubercle aggravated by activity
• X-ray: fragmentation of tibial tubercle ossification center
• Treatment: conservative - activity modification, ice, NSAIDs, quadriceps stretching; resolves at skeletal maturity
• Surgery rare - ossicle resection + tibial tubercleplasty for unresolved cases

• Segment of subchondral bone loses blood supply + may detach from articular surface
• Medial femoral condyle (most common), talar dome, capitellum
• Juveniles: stable lesion, high healing potential; Adults: less likely to heal
• MRI is investigation of choice (shows stability of fragment)
• Treatment: Stable lesion = conservative (restrict activity, 6 months); Unstable/detached = arthroscopic drilling, fixation, or removal of loose body

15. Pelvic Osteotomies in Children

• Redirectional (reorienting): redirect existing acetabulum
  • Salter innominate osteotomy: age 18 months-6 years, redirects anterolaterally - best for DDH with adequate acetabular cartilage; single cut through innominate bone; opens at symphysis pubis
  • Triple osteotomy (Steel/Tönnis/Ganz): older children/adolescents, larger correction possible; cuts ilium + ischium + pubis
  • Ganz periacetabular osteotomy (PAO): near-adult acetabulum, maximum correction, preserves blood supply
• Salvage (augmentative): for late DDH/insufficient cartilage
  • Chiari osteotomy: curved medial displacement osteotomy, fibrocartilage fills superior defect; for older children >8 yrs
  • Shelf procedure (acetabuloplasty): bone graft added above acetabulum laterally
• Reshaping: for Perthes
  • Dega osteotomy: incomplete osteotomy with hinge on medial cortex; favored in CP for posterosuperior deficiency

16. Tarsal Coalition

• Failure of segmentation (mesenchymal differentiation failure) of adjacent tarsal bones
• Calcaneonavicular coalition (most common, 53%) and talocalcaneal coalition (middle facet, 37%)
• Presents in adolescence when coalition ossifies: hindfoot pain, recurrent ankle sprains, peroneal spastic flatfoot (spasm of peroneal muscles)
• X-ray: calcaneonavicular coalition = best seen on oblique foot view ("anteater nose" sign); talocalcaneal = Harris axial view (best) + CT for definitive diagnosis; MRI for fibrous/cartilaginous coalitions
• Treatment: Symptomatic = activity modification, orthotics, casting; Surgical = resection of coalition + fat/muscle interposition (Extensor digitorum brevis for calcaneonavicular); if severe arthritic changes = subtalar or triple arthrodesis

17. Duchenne Muscular Dystrophy (DMD) - Orthopaedic Management

• X-linked recessive, Xp21, absence of dystrophin gene product
• Males only (females are carriers); presents 3-5 years
• Gowers' sign (climbing up own legs to stand from floor) - classic
• Progressive proximal muscle weakness; calf pseudohypertrophy
• CPK markedly elevated; EMG + muscle biopsy confirms
• Orthopaedic deformities: equinus contracture (Achilles), hip flexion contracture, scoliosis (progressive once non-ambulatory)
• Corticosteroids (deflazacort/prednisolone) slow progression and delay scoliosis
• Scoliosis: posterior spinal fusion once Cobb >20-25° in non-ambulatory DMD (early surgery recommended before respiratory function declines FVC <40%)
• Lower limb surgery: Achilles + iliotibial band releases to prolong ambulation
• Prognosis: non-ambulatory by 10-14 yrs; cardiac/respiratory death 20s-30s

18. Non-Accidental Injury (NAI) / Battered Child Syndrome

• Kempe first described battered child syndrome (1962)
• Suspect NAI when: injury inconsistent with history, multiple fractures at different stages of healing, delay in seeking treatment, unusual fracture patterns, bilateral/symmetric injuries
• Classic fractures in NAI: posterior rib fractures (most specific), metaphyseal corner/bucket-handle fractures (high specificity), spiral fractures in non-ambulatory children, bilateral subdural hematomas
• Spiral femur fracture in <1 year old = high suspicion
• Investigations: skeletal survey (full body x-rays), bone scan (may detect occult fractures), ophthalmology (retinal hemorrhages = shaken baby)
• Management: medical stabilization, report to child protection services, multidisciplinary team involvement
• Prognosis: 30% mortality if returned to abusive environment

19. Congenital / Developmental Coxa Vara

• Neck-shaft angle <120° (normal 130-135°)
• Failure of endochondral ossification in the inferomedial femoral neck
• Hilgenreiner-epiphyseal (HE) angle (angle between Hilgenreiner line and femoral capital physis): >60° = likely to progress; <45° = likely to remodel; 45-60° = uncertain
• Inverted Y radiographic sign (triangular fragment in femoral neck = characteristic)
• Clinical: short limb, Trendelenburg gait, limited abduction, painless limp
• Treatment: HE angle >60° or progressive = valgus subtrochanteric osteotomy (aim for neck-shaft angle ~150° to prevent recurrence)
• Can be associated with: cleidocranial dysostosis, rickets, Paget's disease (in adults)

20. Congenital Vertical Talus (Rocker-Bottom Foot)

• Rigid flatfoot deformity with dorsal dislocation of navicular on talus
• Talus is vertically oriented (plantar flexed), calcaneus in equinus
• Foot looks like a rocker-bottom (convex plantar surface)
• 50% associated with systemic conditions (spina bifida, arthrogryposis, chromosomal syndromes)
• X-ray: on lateral view - talus points plantar, calcaneus in equinus; navicular dislocated dorsal to talus (navicular is not ossified until 3-4 years, so difficult to visualize directly - infer from position of first metatarsal axis)
• Forced plantar flexion lateral X-ray: distinguishes CVT (navicular remains dislocated) from oblique talus (navicular reduces)
• Treatment: Reverse Ponseti method (serial casting in opposite direction - plantarflexion/adduction) then single surgical reduction via 2-incision technique (Dobbs method); traditional = Cincinnati incision open reduction
• Must distinguish from: oblique talus (reduces on plantarflexion X-ray), calcaneovalgus foot (flexible), flexible flatfoot

Complete 20-Question Master Table

• Intro box (paragraph overview - good for opening your essay)
• Classification (with mnemonic where applicable)
• Clinical features
• Investigations
• Management (age-based / stage-based)
• Complications
• Red "! IMPORTANT" callouts for must-know facts (surgical emergencies, high-yield traps)