ACLs, OCD, MMT, and PCL Deciphering Knee Injuries in Adolescents

1
ACLs, OCD, MMT, and PCL Deciphering Knee
Injuriesin Adolescents

• William W. Dexter, MD, FACSM
• Maine Medical Center
• Sports Medicine Program

2
Goals of Discussion

• Recognize common injuries
• Acute
• Overuse
• Anatomy and function
• Evaluation
• History/mechanism
• Exam findings
• Imaging
• Management
• Office
• Surgical
• Prevention

3
Epidemiology

• Knee MC injury
• Up to 40!
• Increasing incidence
• elementary, JHS, HS(11)
• 2X rate in non organized sport
• Female ACLs
• epidemic HS, college
• 3.3 of ACL - skeletally immature athlete
• McCarroll et al

4
Preface

• History diagnosis
• Practice your lachman
• Liberal use of xray
• Repair the meniscus
• And the ACLs
• Everything else does well with conservative
  management

5
The Growing Knee

• Growth cartilage
• epiphyseal plate
• articular cartilage
• apophyses
• Physis vulnerable to injury
• acute, overuse
• tendon stronger
• Makes Dx difficult

6
The Growing Knee

• Tanner I II
• physis stronger than ligament
• Tanner III IV
• ligament stronger
• physeal injury
• (Salter-Harris)

7
OCD

• Define separation of osteochondral fragment from
  bed
• Etiology
• repetitive stress
• acute insult
• shearing stress
• vascular insult -- osteonecrosis

8
OCD

• Location
• 85 medial femoral condyle
• Classification
• Grade I
• articular cartilage intact
• Grade II
• unstable
• Grade III
• free fragment(s)

9
OCD

• History
• adolescents, male
• bilateral 25
• vague symptoms
• catch, swell, ache
• mechanical w/ fragment
• Exam
• flex knee, point tender
• decreased ROM

10
OCD

• Image
• X-ray tunnel view
• MRI needed

11
OCD

• Management
• open physis do well with conservative
• restrict activity
• below pain threshold
• may require NWB
• sequential imaging
• X-rays
• MRI

12
OCD

• Surgery
• IF
• no better, no healing
• unstable fragment
• methods
• drilling
• fixation fragment
• excise and repair
• abrasion
• microfracture
• osteochondral graft
• autologous transplant

13
OCD

• Do these techniques work?
• although it has not yet been proved that
  thisincreases healing, we have a strong clinical
  impression that this is the case.
• Outerbridge, 1995
• What about in 2007?
• RTP high impact sports
• Younger may do better

Mithoefer, AJSM, 2006 Gudas, Arthroscopy, 2005
14
Acute Knee Injuries

• Ligament Injuries
• ACL
• MCL
• LCL
• PLC
• PCL
• Meniscal Injuries
• Evaluation and Management

15
Anterior Cruciate Ligament

• Skeletally immature
• incidence increasing
• Anatomy and Function
• P-M condyle to Ant-ctr tibia
• tension through ROM
• Restrains tibia
• 90 anterior displace
• secondary IR, valgus
• Gender/maturation difference (kinematics)

Quatman, JBJS, 2003
16
Anterior Cruciate Ligament

• Mechanism Injury
• contact v.non contact
• patellar dislocation
• Associated injury
• up to 60
• meniscal tear
• 20-50 children
• avulse tibial spine
• under recognized
• Type I - III

Bales, AJSM, 2004
17
Anterior Cruciate Ligament

• History
• feel pop
• unstable
• collapse
• recur
• rapid swelling
• pain /-

18
Anterior Cruciate Ligament

• Exam
• positive Lachman
• ?aspirate, anesthetize
• effusion
• consider xray first
• Reliability exam
• lt 12 yo is poor
• Fehnel Johnson
• 95 accurate
• Stanitski

19
Anterior Cruciate Ligament

• Imaging
• Xray
• AP, lat, tunnel
• MRI
• sensitivity debated
• range 60-98

20
Anterior Cruciate Ligament - Management

• Natural History
• poor prognosis if left untreated !
• chondral, meniscal injury w/in 5 years
• Conservative Treatment
• brace
• strengthen
• limit activity
• (YEAH RIGHT)

21
Anterior Cruciate Ligament - Management

• Conservative often fails
• unstable, swell, pain
• early DJD
• Evidence
• 27 non op, 4 yr... f/u
• Angel, et al
• 9/16 HS, 37/38 JHS
• McCarrol, et al
• definitive study
• only 75 patients

22
Anterior Cruciate Ligament - Managements

• Surgical Treatment
• repairs do well
• Micheli 55/60
• McCarrol 2-10 yr. f/u
• Physis at risk potentially severe consequences
• epiphysiodesis (theoretic? animal models)
• few reports of significant growth abnormality
• clinical studies
• One large con
• Shelbourne, et al, AJSM 9/2004 pro if careful

23
Anterior Cruciate Ligament - Management

• Surgical Treatment
• Who/When
• within 1-2 years closure
• lt 1 cm. Growth left
• ACL
• Who not
• wide open physis
• no growth spurt yet
• Tanner 1-2
• Indications changing

Bales, AJSM, 2004 Dorizas, OrthClinNoAmer,2003
24
Anterior Cruciate Ligament - Management

• Surgical Treatment
• Evidence mounting
• How
• Std. repair if older
• for younger
• trial conservative
• low threshold to fix
• modified repair ?
• ITB, hamstring
• avoid physis
• RTP ROM, strength, function, FEAR

Kvist,KneeSurgSpTrArth, 2005 Bales, AJSM, 2004
25
Prevention of ACL injury

• Neuromuscular training programs proven benefit
• In and out of season
• Structured, warm up
• Focus on landing
• Reduce mechanical risk factors
• Knee abduction
• Hip kinematics

Mykelbust, Inst Course Lec, 2007 Myer,
MusculoskDisorders, 2007 Pollard, CJSM,
2006 Olsen,BMJ, 2005
26
Dislocated Patella

• Mechanism
• plant foot, valgus
• medial rotate femur
• similar to ACL !
• Natural History
• 11000
• most will reduce
• up to 50 recur

27
Dislocated Patella

• Imaging
• 23 osteochondral injury on X-ray
• 70 on arthroscopy!
• Stanitski, et al
• get MRI

28
Dislocated Patella

• Management
• Conservative
• normal knee 75
• abnormal lt 50
• Cash Hughston
• SLI v. protected ROM
• PT
• Surgery
• if fragments
• ? Repair first time dislocation

Satterfield, Arthroscopy, 2005
29
Medial Collateral Ligament

• Anatomy and Function
• several layers
• attaches to meniscus
• static stabilizer
• primary role
• resist valgus, ER
• secondary role
• anterior translation tibia
• if ACL/MCL - bad injury

30
Medial Collateral Ligament

• Mechanism
• contact valgus
• non contact ER knee
• Grading
• I -III

31
Medial Collateral Ligament

• History
• pain, night pain
• unstable sensation
• Exam
• point tender
• /- swollen
• valgus stress
• 0, 20-30 degrees
• lax at 0 Grade III

32
Medial Collateral Ligament

• Imaging
• Xray r/o physeal injury
• MRI
• not needed
• protect, rehab, recheck
• Treat non-operative
• brace (ROM)
• aggressive rehab
• Micheli, Jones, et al
• Brace v.surgery if assoc. injury
• RTP

33
Lateral Collateral Ligament

• Not common
• Lateral Ligament Complex
• Substantial
• Function
• varus restraint
• limits ER
• provides postero-lateral stability

34
Lateral Collateral Ligament

• Mechanism
• varus force
• hyperextension
• Findings
• pain, tender focal
• decrease ROM
• check PLC !!
• Treat as MCL

35
PLC Injury Dont miss this one!

• Limited time to fix primarily
• Significant functional limitations
• Gait disturbance
• Instability

36
The Patient

• 17 year old male athlete (fb, wrestling,
  basketball) CC My knee hurts
• HPI 2 weeks ago, playing basketball, knee
  locked up -felt like it came out of the socket
• swollen and painful
• feels unstable, occasionally gives out
• previous injury 9 months ago fell on his knee
• Since then, it has not felt very stable

37
Physical Exam

• Inspection normal
• Palpation tender in popliteal area
• ROM full
• Strength RROM 5/5
• Gait normal.
• Special Tests
• Patellar tilt and shift negative
• Meniscus flexion pinch test (pain
• MCL/LCL normal
• PCL slight sag at 90 degrees, negative posterior
  drawer
• Anterior drawer increased anterior motion, but
  solid end-point
• Positive dial at 30 degrees of flexion with pain
  and some subluxation

38
Other PLC stability contributors(Much variation,
complex interaction)

• Arcuate complex
• Fibular collateral ligament
• Arcuate ligament
• Popliteal tendon
• Fabello-fibular ligament
• Lateral coronary ligament
• Posterior capsule
• Lateral gastrocnemius tendon
• Iliotibial tract
• Long and short heads of biceps femoris

39
PLC Injuries

• Anterior drawer at 90 degrees
• Neutral
• External tibial rotation
• Posterior drawer at 90 degrees
• Neutral
• External tibial rotation
• Posterolateral ExtRot
• 90 degrees
• 30 degrees
• ADduction at 30 degrees
• Abduction at 30 degrees
• Pivot shift
• Reverse pivot shift
• External rotation recurvatum

• N71 w/ suspected PLC injuries
• EUA
• Surgical findings
• Correlate exam finding with anatomical area of
  injury

LaPrade,AmerJSportsMed 254.1997
40
PLC

• Anatomical areas injured
• Common sites injured
• Arcuate complex
• Deep layers ITT
• Short head biceps
• Fibular ligaments
• Less commonly involved
• Superficial layers ITT
• Long head biceps
• Lateral gastroc

• Exam tests utility
• Positive Predictive Value
• Negative Predictive Value

41
Beware of Associated Injury!

• 75 of PCL injuries 2 or more regions involved
  simultaneously
• Also
• peroneal nerve injuries
• avulsion fracture
• torn PCL

42
Positive predictive values
43
Negative predictive values
44
Stability tests and associated injuries

• Arcuate ligament Adduction at 30 flexion
• Fibular collateral Reverse pivot shift,
  posterolateral external rotation at 30 flexion
• (p0.01)

45
Posterolateral external rotation test at 90
degrees
46
Posterolateral external rotation test at 30
degrees
47
Adduction stability test at 30 degrees
48
Reverse pivot shift test
49
External rotation-recurvatum test
50
PLC Conclusions

• The PLC is a complex and varied structure that is
  made up of a number of anatomical components.
• Injuries to different components of the PLC cause
  variations in the outcome of stability testing.
• BE SUSPICIOUS, learn a few tests, refer early.

51
Getting back to our patient

• Blew off his MRI!!!
• MRI and/or
• exam under anesthesia necessary
• Will probably need surgery
• depending on degree of instability

52
Posterior Cruciate Ligament

• Unusual but incidence on the rise
• Anatomy
• hourglass, intrasynovial
• medial femoral condyle to post tibia
• Ligs Humphrey, Wrisberg - lat meniscus
• Primary restraint to posterior translation

53
Posterior Cruciate Ligament

• History
• knee flexed, direct hit
• hyperextension
• /- effusion
• Exam findings
• posterior sag/drawer
• may be false neg.

54
Posterior Cruciate Ligament

• Imaging
• Xray
• r/o avulsion
• MRI
• Treatment
• natural history unknown
• surgery v. conservative

55
Meniscal Injury

• 5-10 all sports injuries in children
• Unusual prepubertal
• thick and vascular
• as age
• thins out
• less vascular
• more injury

56
Meniscal Injury

• Functional Anatomy
• mobile
• lateralgtmedial
• plastic deformity
• absorbs force
• 50-100 GRF
• dissipates energy
• protect articular surface
• joint stability
• Medial 50 surface
• Lateral 70

57
Meniscal Injury

• Types of injury
• Longitudinal tears 50 to 90
• displaced bucket-handle tears are not uncommon
• meniscal injuries often associated with ACL
  injuries
• discoid

58
Meniscal Injury

• History
• typical mechanism
• slow swelling
• focal pain
• catch/pop/lock
• unstable
• Exam
• lacks full extension
• effusion
• tender
• meniscal signs

59
Meniscal Injury

• Xray
• to r/o bony, epiphyseal, IALB, OCD
• MRI
• adults gt90 sens/spec
• children less so (?)
• 70-90 sens/spec
• less so for younger

Kocher, OrthoClinNoAmer, 2003
60
Meniscal Injury

• Treatment is surgical
• untreated do poorly
• menisectomy
• ?poor outcome
• 60 _at_ 5 yrs
• Manzione, et al
• 87 OA _at_ 7 yrs
• Zaman, et al
• meniscal repair best
• peripheral tear (MC)
• requires stable knee
• longer rehab

61
Discoid Meniscus

• Anatomical variant types I-III
• Not rare (1-2)
• Meniscus injury lt age 10 unusual unless
  associated with a discoid meniscus.
• Similar symptoms
• intermittent
• Vague
• Snapping
• horizontal cleavage tears MC
• MRI - thin cuts
• Remove(saucerize) v. repair

Kocher, OrthoClinNoAmer, 2003
62
Final Thoughts

• Common injuries, on the rise
• Dont be shy
• with imaging
• with exam
• with follow up
• with referral