Transcript ACL, Meniscal, and Catilage Injuries in the Skeletally

ACL Injuries In the
Skeletally Immature
Jason W. Folk, MD
Steadman Hawkins Clinic of the Carolinas
February 2012
Disclosures
Consultant Smith & Nephew Endoscopy
Objectives

Describe the epidemiology,
pathophysiology, and treatment principles
of ACL injuries in skeletally immature
patients
ACL Injuries:
Introduction

Epidemiology:
– Intrasubstance tears once
considered rare in pediatric
population
– Tibial eminence fx considered
pediatric ACL equivalent
 Typically under 12yo
– Increasing numbers over past
decade
– Increased attention
ACL Injuries:
Introduction

Reasons for increased
incidence:
– Increased participation in
sports
– Higher competitive levels
early on
– Increased awareness of
injury
– Decreased conditioning
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ACL Injuries:
Introduction
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ACL Injuries in Soccer Players 5-18 (Shea,
et al. JPO 2004.)
– Based on insurance data from 6 million
player-years
– 6.7% of total injury claims
– 30.8% of all knee injury claims

True incidence unknown
ACL Injuries:
Introduction

Differences in pediatric population
– Often lack fully developed complex motor
skills
– May have temporary decline in motor and
balance during puberty
– Open physes
– Higher strength of ligaments vs. boneligament interface
ACL Injuries:
Diagnosis

History:
– Patient describes a
characteristic “Pop”
– Effusion forms quickly after
injury
 47% of patient’s aged 7-12
with traumatic effusion had
ACL disruption
 65% in 13-18 year old group.
(Stanitski et al. 1993)
 Approximately 60% partial
tears
ACL Injuries:
Diagnosis

Physical Exam
– Often more difficult in kids than adults
 Acute pain
 Frightened
 Unable to relax
– Examine uninjured leg for baseline laxity or
congenital absence of ACL
ACL Injuries:
Imaging
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Plain Radiographs (4 views)
– For anyone suspected of having
an ACL injury
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Bony avulsions
Osteochondral fractures
Physeal fractures
Patellar dislocation/subluxation
Degree of physeal closure
– CT scan also used for evaluation
of physeal closure.
Tibial Eminence Fracture

In skeletally immature,
chondroepiphysis is
weaker than the ligament.

Mechanism of injury
typically hyperflexion
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Most commonly 8-12yo
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Present w/ pain and
limited ROM
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Dx on x-ray and CT
Tibial Eminence Fracture
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Type I: LLC x 3-6 weeks in 20degrees flexion
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Type II/III: Attempted closed reduction,
+aspiration of hemarthrosis (may help
reduction), LLC in extension x 4-6 weeks
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Irreducible Type II/III or IV: arthrocopic vs
open ORIF with suture, retrograde wire, or
screw fixation

Some argue all Types II-IV should be fixed
anatomically with countersinking of fragment
because of residual laxity
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Results of fixation usually excellent
ACL Injuries:
Imaging

MRI
– Should not be used as replacement
for physical exam and routine
radiographs
– Look for ACL tear, meniscal injury,
chondral injury
– Indications
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Failing to improve ROM
Persistent effusion
Physical exam difficult to interpret.
Help define anatomy of physis
ACL Injuries:
Etiology

Can occur with fractures
– Distal femoral physeal fractures
(25-45%)
– Salter-Harris III fxs at increased
risk because frequently exits
intra-articularly at notch
– Proximal tibial physeal fractures
The Physis

Concern about
iatrogenic injury to
physis is what drives
the debate about
treatment strategies
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The Physis
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Distal femoral and
prox tibial physis
– Contribute more to
limb length than hip
and ankle
– DF 1.2 cm/yr
– PT 0.9 cm/yr
– Overall 65% of length
contributed to knee
– Closure typically occurs
 M=16
 F=14
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Anatomy of Physis
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MRI closure of Physis
– 0% at 11 years
– 5% at 12 years
– 34% at 13 years
– 53% at 14 years
– 94% at 15 years
– 100% at 16 years
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Central tibial physis closes prior to
peripheral physis
– ?More central tunnel
– ?Smaller tunnel
Sasaki et al., J Knee Surg 2002
ACL Injuries:
Treatment

Concern for possible growth abnormality fuels
debate on treatment
– Non-operative
– Operative
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Direct Repair
Extra-articular
Intra-articular
Intra/Extra articular reconstructions
–
–
–
–
Physeal sparing
Partial Transphyseal
Complete transphyseal
Trans epiphyseal
ACL Injuries
Nonoperative Management
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Avoids risk of physeal
damage
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Sometimes used as a
temporizing measure until
skeletal maturity
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Very difficult to reasonably
limit young patient’s
activities
ACL Injuries:
Nonoperative management
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So what if we don’t treat
these injuries?
– Angel et al. Arthroscopy
1989
 27 children with
arthroscopically documented
ACL tears
 22 patients at 51mo f/u
 None able to return to
sports at preinjury level
Non-op ACL Open Physis
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40 pts under 14 y/o open physis
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16 conservative
– 6 scope for meniscal tears
– Only 7 return to sports
 All recur giving way, swelling, pain
McCarroll et al., AJSM 1988
Non-op ACL Open Physis
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18 pts ACL injury open physis
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Only one returned to preinjury
level of sports
Initial scope 13 meniscal tears
Later secondary meniscal tears
in 9
Degen changes 11 of 18 pts by
Xray
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Mizuta et al., JBJS Br 1995
Non-op ACL Open Physis
60 children with ACL tear
 23 nonop
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• Nat Hx continued instability, further
meniscal and chondral damage
• 25 % secondary meniscal tears
• Few able to participate in sports
Aichroth et al., JBJS BR, 2002
Non-op ACL Open Physis
? Effect of delay in treatment
 39 pt < 14 y/o
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Sig increase in MMT with
delay in treatment > 6
weeks
• 36% chronic vs 11% in
acute
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Rx
No diff in rate of LMT
Millett et al., Arthroscopy 2002
ACL Injuries
Nonoperative Management
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Graf et al:
– 12 skeletally immature patients with ACL tears
– 8 patients underwent non-op and no restriction
management.
 7 of the 8 had new meniscal tear at follow up
ACL Injury:
Long Term Results
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Kannus et al. JBJS-B. 1988
• 8 year F/U – 4/7 Pediatric Patients that had
Untreated ACL Tears showed Advancing OA
radiographically
Nonoperative Rx in Children
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Non-op treatment
has not resulted in
good outcomes
ACL Injuries:
Physeal Concerns
Fear disruption of open physes
 Risk of epiphysiodesis, LLD,
angular deformity
 Caused by crossing physis with
bone plug and/or fixation
devices
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ACL Injuries:
Physeal Concerns
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History
– Campbell et al. (1959)
 Large holes drilled through the physis have maximal
retardation of growth plate
 Insertion of cortical bone across physis causes arrest
– Makel et al (1988)
 Destruction of >7% of physis causes growth arrest
 Destruction of 3% or less…no arrest
– Stadelmeir et al (1995)
 Soft tissue graft placed in drill hole did not cause physeal
bar.
Factors Influencing Physeal Arrest
Diameter of drill hole
 Soft tissue graft within tunnel
 Tension of graft across physis
 Tunnel location? (Central and vertical)
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ACL Injuries:
Operative Managment
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Direct Repair:
– A historic treatment modality
– Inflammatory changes and degeneration
begins within 48 hours after injury
– Metalloproteases and cytokine inflammatory
factors affect healing potential of direct repair
– Poor results
 Delee and Curtis, CORR 1983
 Engebretsen, et al. Acta Orthop Scand 1988
ACL Injuries:
Operative Management
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Extra-Articular repair
– Temporizing method
– Non-anatomic reconstruction
– Poor results
 Dahlstedt , et al. Acta Orthop Scand 1988
 McCarroll et al. AJSM 1998
 Graf, et al. Arthrsocopy 1992
ACL Injuries:
Assessment of maturity
Tanner et al. :
– Adolescent growth spurt begins at
12.5 years in boys and 10.5 years in
girls.
– Peak Growth velocity 1 year later
 Menarche is good indication of maturity
in girls
– In athletic girls, menarche may be
delayed.
 Axillary and pubic hair appear in boys
after growth spurt
 Bone age: Most accurate method to
determine skeletal maturity
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General Guidelines
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Think about physis if:
– Male
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Tanner stage 1 or 2
Not shaving
Not reached growth spurt
14 y/o or less
– Female
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Premenarchal
Tanner stage 1 or 2
Not reached growth spurt
12 y/o or less
ACL Reconstruction Techniques
ACL Injury:
Physeal Sparing Reconstruction
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Intra-articular, non-anatomic, extra-physeal
Stanitski. JAAOS 1985
ACL Injury:
Kocher Technique
Physeal-Sparring Combined Intra- and Extra-articular Reconstruction
ACL Injury:
Partial Transphyseal
Hybrid of physeal
sparing and adult-type
reconstruction
 Femoral physis left
intact
 Graft: Hamstring or
patella
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– Passed through 6-8mm
tunnel
 <5% physeal X-sectional
area
– Fixed in over the top
position
ACL Injury:
Transepiphyseal
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ACL Injury:
Transphyseal
Thank You