Femoral Shaft Fractures - Pediatric - Pediatrics

Introduction

High suspicion for child abuse required
- abuse must be considered if child is < 3 years
  - especially if present in a patient before walking age
- femur fractures are the 2nd most common child abuse associated fracture after humerus fractures
Epidemiology
- bimodal distribution
  - increased rate in toddlers age 2-4 yrs.
  - increased again in adolescents
Mechanism
- correlated with age due to the increasing thickness of the cortical shaft during skeletal growth and maturity
  - falls most common cause in toddlers
  - high energy trauma is responsible for second peak in adolescents
    - MVC or ped vs vehicle
- fractures after minor trauma can be the result of a pathologic process
  - bone tumors, OI, osteopenia, etc.

Classification

Descriptive classification
- characteristics of the fracture
  - transverse
  - comminuted
  - spiral etc.
- integrity of soft-tissue envelope
  - open
  - closed fracture
Stability
- length stable fractures
  - are typically transverse or short oblique
- length unstable fractures
  - are spiral or comminuted fractures

Presentation

Symptoms
- thigh pain, inability to walk, report of deformity or instability
Physical exam
- gross deformity, shortening, swelling of the thigh

Imaging

Radiographs
- AP and lateral of femur
  - typically allow complete evaluation of the fracture location, configuration and amount of displacement
- ipsilateral AP and lateral of knee and hip
  - required to rule out associated injuries

Treatment

Based on age and size of patient and fracture pattern
Guidelines provided by AAOS

Treatment Guidelines
< 6 months	Any fx pattern	Pavlik harness Early spica casting
6m - 5 years	< 2 - 3 cm shortening	Early spica casting
6m - 5 years	> 2 - 3 cm shortening polytrauma/multiple fx/open fx	Traction with delayed spica casting ORIF with submuscular bridge plating Flexible nails External fixator
5 - 11 years	length stable fx (transverse or oblique fx patterns)	Flexible intramedullary nails
5 - 11 years	length unstable fx (comminuted or spiral) very proximal or distal fx	ORIF with submuscular bridge plating External fixation polytrauma patients for damage control
11 or greater years Shaft Fracture	patient weighs < 100 lbs	Flexible intramedullary nails
	patient weighs > 100 lbs	Antegrade IM nail with trochanteric or lateral starting point
	very proximal or distal fx	ORIF with submuscular bridge plating

Surgical Techniques

Pavlik harness
- indications
  - children up to 6 mos.
- technique
  - avoids the need for sedation or anesthesia
  - straps can be adjusted to manipulate fracture
- complications
  - can compress femoral nerve if excessive hip flexion is used in presence of a swollen thigh
    - identified by decreased quadricep function
Immediate spica casting
- fewer complications than traction + later casting
- indications
  - children 6 m - 5 years
  - relatively contraindicated with polytrauma, open fractures and shortening > 2-3 cm
- technique
  - applied with reduction under sedation or with GA
  - single-leg spica or one-and-one-half spica (to control rotation)
    - the exception is distal femoral buckle fracture (stable) only requires long leg cast (not spica)
  - hips flexed 60-90° and approximately 30° of abduction
  - MUST limit compression and/or traction thru popliteal fossa
  - external rotation is typically needed to correct rotational deformity
  - molds along the distal femoral condyles and buttocks help to maintain reduction
  - acceptable limits are based on childs age
    - goal of reduction should include obtaining < 10° of coronal plane and < 20° of sagittal plane deformity with no more than 2cm of shortening or 10° of rotational malalignment
  - a special car seat is needed for transport
- follow-up
  - weekly radiographs to monitor for loss of reduction for first 2 to 3 weeks
    - cast wedging can be used to correct deformities
  - healing times vary from 4 - 8 weeks based on age
- complications
  - compartment syndrome
    - decreased with applying smooth contours around popliteal fossa, limiting knee flexion to < 90° and avoiding excessive traction
    - monitored for by observing the child's neurovascular exam and level of comfort
Traction + delayed spica casting
- indications
  - children 6 mos. - 5 yrs. of age with > 2 - 3 cm of shortening
- technique
  - placed in distal femur proximal to distal femoral physis
    - proximal tibial traction can cause recurvatum due to damage to the tibial tubercle apophysis
  - used for 2-3 weeks to allow early callus formation
  - spica casting then applied until fracture healing
- complications
  - more complications than immediate spica casting
Flexible intramedullary nails
- indications
  - treatment of choice for most simple, length stable fracture patterns in children 5 - 11 years
  - adolescent patient weighing less than 100 lbs with a length stable fracture
- technique
  - allows load sharing and quick mobilization of the patient
  - nail size determined by multiplying width of narrowest portion of femoral canal by 0.4
    - the goal is 80% canal fill
  - two nails of equal size are inserted retrograde beginning approximately 2 -2.5 cm above the distal femoral physis
- follow up
  - time to union is typically 10 - 12 weeks
  - removal of the nail can be performed at 1 year
- complications
  - most common complication is pain at insertion site near the knee
    - in up to 40% of patients
    - recommended that < 25mm of nail protrusion and minimal bend of the nail outside the femur are present
  - increased rate of complications in patients 11 years or up or > 50 kg
  - increased rates of malunion and shortening in very proximal and distal fractures, as well as significantly comminuted fractures
Submuscular bridge plate fixation
- indications
  - comminuted, length unstable fractures
  - very proximal (subtrochanteric) or very distal fractures (distal diaphyseal or metadiaphyseal)
- technique
  - fracture is provisional reduced with closed or percutaneous techniques
  - small proximal + distal incisions and plate is placed between periosteum and vastus lateralis on the lateral side of the femur
  - typically use 12-16 hole 4.5mm narrow LC-DC plate with 3 screws proximal and 3 screws distal to fracture
    - the plate may need to be bent to accomodate the natural bend of the femur
    - locking fixation can be used in osteoporotic areas or in very proximal or very distal fractures with limited area for fixation
  - weightbearing is restricted until visible callus formation at an average of 5 weeks
- advantages
  - stability allows for early mobility
  - preserves blood supply to femoral head
  - performed with minimal surgical exposure and soft-tissue dissection
- disadvantages
  - steep learning curve
  - load bearing implant
  - multiple stress risers following removal of hardware
Antegrade rigid intramedullary nail fixation
- indications
  - in patients 11 years or older
  - length unstable fractures
  - fractures in patients weighing > 100 lbs
- technique
  - use greater trochanter or lateral entry nails
    - decreased risk of ON
  - do not cross distal physis of femur
- advantages
  - rigid fixation with interlocking screws control length and rotation even in significantly unstable fractures
  - permits early weightbearing
  - decreased risk of angular malunion
- complications
  - ON risk is 1-2% with piriformis start in a patient with open proximal physes
  - exact risk of ON with greater trochanter and lateral entry nails is unknown
  - secondary deformities of the proximal femur can occur after greater trochanteric insertions
    - narrowing of the femoral neck
    - premature fusion of greater trochanter apophysis
    - coxa valga
    - hip subluxation
External fixation
- indications
  - damage control orthopaedics in a polytrauma patient
  - open fractures
  - associated vascular injuries requiring revascularization
  - fractures with associated soft tissue concerns
  - segmental or significantly comminuted fractures
  - multiply injured patient
- technique
  - applied laterally
    - avoid disruption and scarring of quadriceps
  - 10 - 16 weeks of fixation is typically needed for solid union to occur
  - weightbearing as tolerated can be considered with stiff constructs
- complications
  - more complications than internal fixation
  - pin tract infections are frequent
    - as high as 50% of fixator related complications
    - treated with oral antibiotics and pin site care
  - higher rates of delayed union, nonunion and malunion
  - increased risk of refracture (1.5-21%) after removal of fixator especially with varus malunion

Complications

Leg-Length Discrepancy
- overgrowth
  - 0.7 - 2 cm is common in patients between of 2 - 10 years at time of fracture
  - typically presents within 2 years of injury
- shortening
  - is acceptable if less than 2 - 3 cm because of anticipated overgrowth
  - can be symptomatic if greater than 2 - 3 cm
    - temporary traction or internal fixation used to prevent persistent shortening
Osteonecrosis (ON) of femoral head
- reported with both piriformis and greater trochanter entry nails
- femoral nailing through the piriformis fossa is contraindicated in adolescents with open physes because of the risk of osteonecrosis of femoral head
- main supply to femoral head is deep branch of the medial femoral circumflex artery
  - branches into superior retinacular vessels that supply the femoral head
  - vulnerable as it lies near the piriformis fossa
Nonunion
- higher risk with load bearing devices
  - external fixator or submuscular plates
- can occur after flexible intramedullary nailing in patients
  - aged over 11 years old
  - who weigh >49 kg (>108 lb)
Malunion
- typical deformity is varus + flexion of the distal fragment
- remodeling is greatest in sagittal plane (ie flexion/extension deformity)
- rotational malalignment does not remodel
  - must be corrected at the initial surgery
Refracture
- most common after external fixator removal with varus malalignment
- highest risk in transverse and short oblique fractures
- less likelihood of secondary callus formation

Femoral Shaft Fractures - Pediatric

Spica Casting for Femur Fractures

Technique guide are not considered high yield topics for orthopaedic standardized exams including the ABOS, EBOT and RC.

Flexible IMN for Femur Fractures

Technique guide are not considered high yield topics for orthopaedic standardized exams including the ABOS, EBOT and RC.

Core Webinar - PEDIATRIC HIP AND FEMUR TRAUMA - by CHLA

Pediatric Femur Flexible Intramedullary Nail Fixation

Spica Cast Technique

Subtrochanteric fracture extended to the neck in female child (C2348)

Hip fracture-dislocation - Femoral head necrosis (C1877)

femur fracture (C1439)

Oral Boards: Femur Fractures - Pediatric

Spica Casting for Femur Fractures Technique guide are not considered high yield topics for orthopaedic standardized exams including the ABOS, EBOT and RC.

Flexible IMN for Femur Fractures Technique guide are not considered high yield topics for orthopaedic standardized exams including the ABOS, EBOT and RC.

Core Webinar - PEDIATRIC HIP AND FEMUR TRAUMA - by CHLA

Pediatric Femur Flexible Intramedullary Nail Fixation

Spica Cast Technique

Subtrochanteric fracture extended to the neck in female child (C2348)

Hip fracture-dislocation - Femoral head necrosis (C1877)

femur fracture (C1439)

Oral Boards: Femur Fractures - Pediatric

Spica Casting for Femur Fractures

Technique guide are not considered high yield topics for orthopaedic standardized exams including the ABOS, EBOT and RC.

Flexible IMN for Femur Fractures

Technique guide are not considered high yield topics for orthopaedic standardized exams including the ABOS, EBOT and RC.