Date post: | 17-Dec-2015 |
Category: |
Documents |
Upload: | avis-belinda-boone |
View: | 213 times |
Download: | 1 times |
Pediatric Knee Injuries
Greg M. Osgood, MD Revised 2011
Additional images courtesy of Paul Sponseller, MD and Arabella Leet, MD
First edition by Steven Frick, MD
Significance
LE growth:– Distal femur: 10mm / yr
– Proximal tibia: 6mm / yr
– Tibia tubercle growth arrest can lead to recurvatum
Fractures of the distal femoral and proximal tibial physis account for 2.2% of physeal fractures BUT they account for 51% of partial growth
plate arrest
Peterson HA, et al. JPO 1994;14(4):423.
Overview
Extra-articular injuries
Intra-articular injuries
Overview
Extra-articular Knee Injuries– Distal Femoral Epiphysis– Proximal Tibia Epiphysis
– Tibia Tubercle – Patella
Overview
Intra-articular Knee Injuries– Tibial Eminence Fractures– Osteochondral Fractures
– Patella Dislocation– Menicus Injuries– Ligament Injuries
Distal Femoral Epiphyseal Fractures
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Anatomy– Distal femoral physis contributes 70% of femoral growth and 37% of lower extremity
length– Popliteal artery and geniculates lie posterior to
metaphysis and capsule
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Fracture Epidemiology– Rare injury (<1% of pediatric fractures)
– Mechanism: • Often the result of high energy trauma in <11 y.o. (pedestrian struck or
fall from a height)• Sports injuries in teens (2/3 of distal femoral fractures)
• varus/valgus force• hyperextension of the knee
Associated Injuries– Do not miss VASCULAR INJURY or TIBIAL/PERONEAL
NERVE INJURY– Do not miss COMPARTMENT SYNDROME
Riseborough EJ, et al. JBJS(A) 1983;65:885.
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Physical Examination– Pain
– Inability to bear weight– Obvious deformity
– Swelling and ecchymosis
– Anterior displacement may be associated with
vascular injury
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Associated Injuries– Knee ligament injury (8-43% incidence)
• Requires close follow-up of knee stability as fracture heals• Repair at time of other intra-articular repair
– Vascular Injury• May be associated with anterior fracture displacement
• Remember pulseless limb may regain normal pulses after fracture reduction and splinting
• Revascularization should be coordinated with vascular surgery team if necessary
– Nerve Injury• Peroneal injury rare
• Observation at least 3 months is indicated, followed by EMG if symptoms persist
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Radiographs– AP & LAT xrays
– Valgus or Varus Deformity Common– Rarely Anterior Displacement
– Oblique views may be necessary– Comparison contralateral xrays
• (expecially in infants – consider USG)– Consider stress xrays
– CT may help evaluate fracture complexity– MRI
Classification– Salter-Harris (I and II most common)
– Displacement (anterior, posterior, valgus/varus)
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Interventions– Closed reduction and immobilization– Closed reduction and internal fixation
– ORIF
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Closed Reduction and Casting– Used only in truly nondisplaced and stable fractures
– Anatomical reduction is more important close to age of skeletal maturity
– Remodeling potential is greatest in plane of knee motion (flexion/extension)
– Discuss potential for growth disturbance or malalignment with family when treatment is initiated
– Frequent follow-up is required to prevent malunion
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Closed Reduction and Casting– Closed reduction usually successful within 10 days
– Well molded splint in slight knee flexion – Periosteum is often intact on compression side of fracture – compression side of fracture should be put
under tension in splint/cast– Partial WB started at 2-3 weeks
– Splint/cast removal between 4-8 weeks– 43-70% displace without internal fixation
Thomson J. JPO 1995;15:474.Graham JM. CORR 1990;255:51.
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Closed Reduction and Internal Fixation
– Reduction performed with TRACTION and angular correction
– Fixation should not cross physis if possible
• Screws may be placed parallel to physis at the metaphysis (Salter II &
IV) or epiphysis (Salter III & IV)
– Use smooth pins to cross physis if necessary
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Open Reduction and Internal Fixation– INDICATIONS• Fractures that cannot be satisfactorily reduced closed
• Salter III and IV fractures
• Open fractures
• Floating knee
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Extra-articular Knee InjuriesDistal Femoral EpiphysisOpen Reduction and Internal Fixation
– Preoperative CT may help plan fixation strategy– Reduction facilitated by removal of interposed muscle
and periosteum– Fixation parallel to physis
– Cross physis with smooth wire fixation only if necessary to obtain stability
– Support fixation with postop splint or cast– Repair associated collateral ligament injuries at time of
fixation if possible– Remove pins at 3-6 weeks
– Remove splint at 6-8 weeks
Salter IV Distal Femur Fracture
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Open Reduction and Internal Fixation– Plates spanning across growth plate should be
avoided unless patient is at skeletal maturity– Skeletal maturity is often difficult to assess and
is easily overestimated
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Complications of Injury– Ligamentous laxity
– Knee stiffness– Compartment syndrome
– Malalignment– Shortening
– Loss of reduction
Extra-articular Knee InjuriesDistal Femoral Epiphysis
SH II Fx
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Extra-articular Knee InjuriesDistal Femoral Epiphysis
6 mo postop
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Extra-articular Knee InjuriesDistal Femoral Epiphysis
SH IV FX with distal metaphyseal femur fx
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Outcomes– Risk of damage to growth plate and growth
disturbance• Assess leg length, alignment and gait at 6 months
• Follow patients 12-24 months
• Growth disturbance caused by direct trauma or lack of anatomical reduction
• Transphyseal bridging may be demonstrated on MRI
Distal Femur Physeal Bar
Valgus deformity, short limb following distal femur SII fx with growth arrest,
failed bar excision
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Severe growth plate injury 9 years after SH II distal femoral physeal injury in 4 y.o. girl
Proximal Tibial Epiphyseal Fractures
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Fracture Epidemiology– Rare injury (<1% of pediatric fractures)
– Mechanism: • Often the result of high energy trauma (MVC or fall
from a height)
• varus/valgus force
• hyperextension of the knee
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Physical Examination– Pain
– Knee effusion/hemarthrosis– Tenderness at physis
– Limb deformity– Document pulse and neurological examination before and
after reduction
Associated Injuries– Do not miss VASCULAR INJURY or
TIBIAL/PERONEAL NERVE INJURY– Do not miss COMPARTMENT SYNDROME
Extra-articular Knee InjuriesDistal Femoral Epiphysis
Associated Injuries– Knee ligament injury
• Requires close follow-up of knee stability as fracture heals
– Vascular Injury• May be associated with posterior displacement of metaphysis
• Remember pulseless limb may regain normal pulses after fracture reduction and splinting
• Revascularization should be coordinated with vascular surgery team if necessary
– Compartment Syndrome• Tethering of popliteal artery, posterior tibial artery, and
anterior tibial artery place limb at compartment syndrome risk
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Radiographs– AP & LAT xrays
– Frequently minimally displaced & easily overlooked
– Stress xrays may help– CT may help assess possible Salter III or IV
– MRI
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Intervention– Closed reduction and immobilization– Closed reduction and internal fixation
– ORIF
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Closed Reduction and Casting– Indicated in non-displaced fractures
– Possible if stable anatomical reduction achieved with Salter I and II fractures
– TRACTION is key to reduction
– Monitor for iatrogenic peroneal injury after reduction
– Splint/cast (bivalved) reduction in slight knee flexion
– Cast may be removed 6 weeks after injury once radiographic evidence of healing
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Closed Reduction and Internal Fixation– Indicated if UNSTABLE reduction is achieved
in Salter I and II fractures– Percutaneous fixation parallel to physis
– Crossed pins that traverse the physis may be used if stable extra-physeal fixation is not
possible– Splint reduction in slight knee flexion
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Open Reduction and Internal Fixation– Indications:
• Non-anatomical closed reduction
• Displaced Salter III & IV fractures
– Open reduction to remove soft tissue interposition– Internal fixation with screws parallel to physis or
crossed K-wires traversing the physis– Protect fixation with splint in slight knee flexion
Extra-articular Knee InjuriesProximal Tibial Epiphysis
SH IV Proximal Tibia Fx
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Complications– Loss of reduction
– Compartment syndrome– Growth disturbance
– Ligamentous instability
Extra-articular Knee InjuriesProximal Tibial Epiphysis
Growth disturbance– Incidence is limited by anatomical reduction
– May be corrected with resection of bony bridge or osteotomy depending on patient age
Tibial Tubercle Avulsion
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Anatomy– Tibia tubercle physeal development
• Cartilaginous stage: through 9-10 y.o.
• Apophyseal stage: ossification center appears 8-14 y.o.
• Epiphyseal stage: ossification centers of tubercle and epiphysis merge 10-17 y.o.
• Bony stage: physis is closed btw tuberosity and metaphysis
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Fracture Epidemiology– Mechanism
• Jumping sports – eccentric contraction of extensor mechanism during landing
• 98% males
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Physical Examination– Anterior proximal tibia swelling and tenderness
– Joint effusion/hemarthrosis– Palpable bony fragment
– Tented skin– Patella alta may be present
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Associated Injuries– Knee ligament injury
– Meniscal injury– Extensor mechanism disruption
– Tibia plateau fracture
Extra-articular Knee InjuriesTibial Tubercle AvulsionRadiographs
– AP and LAT xrays– Slightly internally rotated
lateral view may aid visualization of tibial tubercle
due to anatomical location lateral to tibial midline
– Fracture is differentiated from Osgood-Schlatter by acute fracture line through physis (Osgood-Schlatter does not
involve the physis)
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Classification (Watson-Jones, with modifications of Ogden, Ryu, and Inoue)
– Type I: Fracture through the tubercle apophysis– Type II: Fracture through the apophysis that extends
between ossification centers of apophysis and epiphysis
– Type III: Fracture through apophysis extends across epiphysis
– Type IV: Fracture through apophysis extends posteriorly at level of tibial phsysis
– Type V: Avulsion of patellar tendon off tubercle physis (sleeve fracture)
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Type III Avulsion Fx
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Intervention– Closed reduction and casting
– ORIF
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Closed treatment and casting– Indications: minimally displaced fractures after
closed reduction– Reduction with knee in extension
– Cast molding above patella is important to maintain reduction
– Maintain in cast for 6 weeks
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Open Reduction and Internal Fixation– Midline incision
– Periosteum is debrided from fracture line – Reduction by knee extension
– Screw or pin fixation should be supported by soft tissue repair
– Protect repair with cylinder cast for 6 weeks
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Type II Avulsion Fx
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Type III Avulsion Fx
Extra-articular Knee InjuriesTibial Tubercle Avulsion
Complications– Growth disturbance
– Compartment syndrome– Symptomatic hardware (approx. 50%)
– Stiffness (loss of flexion)
Patella Fracture
Extra-articular Knee InjuriesPatella Fracture
Mechanism:– Avulsion fractures of patella more likely in
children than adults– Eccentric contraction
– Direct blow (comminuted fracture)
Extra-articular Knee InjuriesPatella Fracture
Physical Examination– Painful swollen knee
– Inability to extend knee– Inability to bear weight
– High riding patella– Apprehension test may be positive if patient has
avulsion fracture secondary to patellar dislocation
Extra-articular Knee InjuriesPatella Fracture
Radiographs– AP & LAT knee xrays
– Sagittal plane fractures may be best seen with sunrise view
– Sleeve fracture – small fleck of bone in extensor mechanism may be only sign of disruption
– Comparison views of normal knee may be required
Extra-articular Knee InjuriesPatella Fracture
Classification– Primary osseous fractures
– Avulsion fractures• Avulsion of pole of patella without significant
avulsion of cartilage
– Sleeve fractures• Avulsion of pole of patella WITH a large portion of
articular cartilage (cartilage, retinaculum, and periosteum may be involved)
Extra-articular Knee InjuriesPatella Fracture
Intervention– Closed treatment with casting
– Open reduction and internal fixation
Extra-articular Knee InjuriesPatella Fracture
Closed treatment– Extensor mechanism is intact
– No significant displacement (<2-3mm at articular surface)
Extra-articular Knee InjuriesPatella Fracture
Open reduction and internal fixation
– Midline incision– ORIF with tension band
wire, cerclage wire, nonabsorbable suture,
screws– Sutures alone sufficient for
patella sleeve fractures– Repair of retinaculum is
recommended– Splint for 4-6 weeks
recommended
Extra-articular Knee InjuriesSummary
ANATOMICAL REDUCTION– Key to preventing physeal arrest, malalignment,
and LLD
PREVENT LOSS OF REDUCTION – Loss of reduction is common if not treated with
stable reduction and fixation
TEMPORARY PROTECTION OF FIXATION– Postop splint/cast important in treatment
Intra-articular Knee InjuriesOverview
Intra-articular Knee Injuries– Tibial Eminence Fractures– Osteochondral Fractures
– Patella Dislocation– Menicus Injuries– Ligament Injuries
Acute Hemarthrosis in Children-without Obvious Fracture
Anterior Cruciate Tear
Meniscal tear
Patellar dislocation +/- osteochondral fracture
Knee InjuriesAcute Hemarthrosis
ACL 50%
Meniscal tear 40%
Fracture 10%
Intra-articular Knee InjuriesTibial Eminence Fractures
Epidemiology– Usually 8-14 year old children
– Mechanism: • Hypertension or direct blow to flexed knee
• Frequently mechanism is fall from bicycle
Intra-articular Knee InjuriesTibial Eminence Fractures
Myers- McKeever Classification– Type I- nondisplaced
– Type II- hinged with posterior attachment– Type III- complete, displaced
Intra-articular Knee InjuriesTibial Eminence Fractures
Intervention– Attempt reduction with hypertension
– Above knee cast immobilization– Operative treatment for block to extension,
displacement, entrapped meniscus– Arthroscopic-assisted versus open arthrotomy– Consider more aggressive treatment in patients
12 and older
Intra-articular Knee InjuriesTibial Eminence Fractures8 to 14 yo
often bicycle accident
Myer-McKeever classification
Tibial Spine FractureTreatment
Reduction in extension
Immobilize in extension or slight knee flexion
Operative treatment for failed reduction or extension block
Tibial Spine Closed Reduction
Follow closely – get full extension
Tibial Spine Malunion-Loss of Extension
Injury Film – no reduction 2 years post-injury- lacks extension
Tibial Spine Fx- Arthroscopic OR,Suture Fixation
Intra-articular Knee InjuriesTibial Eminence Fractures
Outcomes– Generally good if full knee extension regained
– Most have residual objective ACL laxity regardless of treatment technique
– Most do not have symptomatic instability and can return to sport
Intra-articular Knee InjuriesOsteochondral Fractures
Usually secondary to patellar dislocation
Off medial patella or lateral femoral condyle
Size often under appreciated on plain films
Arthroscopic excision vs. open repair if large
Intra-articular Knee InjuriesPatellar Dislocation
Almost always lateral
Younger age at initial dislocation, increased risk of recurrent dislocation
Often reduce spontaneously with knee extension and present with hemarthrosis
Immobilize in extension for 4 weeks
Patellar DislocationNote Medial Avulsion off Patella and
Laxity in Medial Retinaculum
Intra-articular Knee InjuriesPatellar Dislocation
Predisposing factors to recurrence- ligamentous laxity, increased genu valgum,
torsional malalignment
Consider surgical treatment for recurrent dislocation/subluxation if fail extensive
rehabilitation/exercises
Intra-articular Knee InjuriesPatellar Dislocation
Lateral Patellar Dislocation
Intra-articular Knee InjuriesMeniscal Injuries
Epidemiology– Increasing incidence
– Longitudinal and bucket handle tears common– Often associated with ACL tear
Intra-articular Knee InjuriesMeniscal Injuries
Mechanism– Almost exclusively sporting injuries
– Twisting motion that occurs as knee is extending
Intra-articular Knee InjuriesMeniscal Injuries
Physical Examination– Inaccurate for diagnosis of meniscal tear
– Acute swelling and hemarthrosis– Joint line tenderness
– Motion at joint line with varus/valgus stress
Intra-articular Knee InjuriesMeniscal Injuries
Radiographs– Conventional xrays do not visualize
– May be associated with discoid meniscus on MRI
Intra-articular Knee InjuriesMeniscal Injuries
Intervention– Nonoperative – nondisplaced, small, outer 1/3
– Partial meniscectomy - complex tears with degenerative changes
– Meniscal repair – simple tears in inner and middle 1/3 tears
Intra-articular Knee InjuriesMeniscal Injuries
Outcomes– Poor results with sub-total meniscectomy
– Repair is successful in most patients < 30y.o.
Intra-articular Knee InjuriesMeniscal Injuries
Complications– Hemorrhage
– Persistent effusion– Infection– Stiffness
– Neuropathy
Intra-articular Knee InjuriesLigament Injuries
Epidemiology– Increasing incidence
– ACL tear occurs in 10-65% of pediatric hemarthrosis
– Boys 16-18 y.o. in organized sports– Girls 13-15 y.o. in unorganized sports
Stanitski CL. JPO 1993;13:506.
Intra-articular Knee InjuriesLigament Injuries
Mechanism– Cutting maneuvers while running
– Lateral blow to the knee in abduction, flexion, and internal rotation while competing in sports
Intra-articular Knee InjuriesLigament Injuries
Intervention– Nonoperative
• Frequently successful in isolated collateral ligament tears
• May be attempted for incomplete ACL and PCL tears
– Operative • Advocated for complete ACL tears to prevent sequelae
of cartilage damage and meniscal injury
• Advocated for displaced complete PCL injury with bony avulsion (attempted nonop treatment is encouraged for
pure ligamentous injury)
Intra-articular Knee InjuriesLigament Injuries
Knee Dislocation– Unusual in children
– More common in older teenagers– Indicator of severe trauma
– Evaluate for possible vascular injury– Usually require operative treatment – capsular
repair, ligamentous reconstruction
Intra-articular Knee InjuriesOverview
Intra-articular Knee Injuries– Tibial Eminence Fractures– Osteochondral Fractures
– Patella Dislocation– Menicus Injuries– Ligament Injuries
Pediatric Knee Injuries
Extra-articular injuries– Distal Femoral Epiphysis– Proximal Tibia Epiphysis
– Tibia Tubercle – Patella
Intra-articular injuries– Tibial Eminence Fractures– Osteochondral Fractures
– Patella Dislocation– Menicus Injuries– Ligament Injuries
Thank You
E-mail OTA about
Questions/Comments
If you would like to volunteer as an author for the Resident Slide Project or recommend updates to any of the following slides, please send an e-mail to [email protected]
Return to Pediatrics
Index