Ligament Injuries Flashcards

ACL PCL MCL LCL PLC Knee dislocation Proximal tibfib dislocation

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1
Q

Describe the epidemiology of acl injuries?

A
  • Mechanism is non contact pivoting injury
  • Often assoc w meniscal injury
    • 50% lateral meniscal tear w acute acl injury
  • >female athelete 4.5:1
    • neuromuscular forces ( more quads dominant)
    • Landing biomechnics- females land in >extension, higher valgus moment
    • Genetics= COL5A1 gene assoc w reduced risk ACL tears
    • smaller ligaments
    • hormone levels
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2
Q

What are chronic ACL deficient knees assoc with?

A
  • Chondral injuries
  • Complex unrepairable meniscal tears
  • relation with arthritis is contraversial
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3
Q

Describe the ACL anatomy?

A
  • Provides stability to prevent anterior translation of tibia cf femur
  • 2 bundles
    • anteriomedial- tight in flexion
    • posteriolateral- tight in extension, contributes most to rotational stability
  • Blood supply - Middle geniculate artery
  • innervation- Post articular nerve
  • Composition
    • 90% type 1 collagen
    • 10% type 2 collagen
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4
Q

Describe the presentation of an ACL lig injury?

A
  • Presentation
    • felt a pop
    • pain deep in knee
    • immediate swelling 70%- haemarthrosis
  • O/E
    • effusion
    • quads avoidance gait- dont’actively extend knee
    • Lachman test
      • a= firm endpoint, B= no endpoint
      • grade1 <5mm translation
      • grade 2 5-10 mm translation
      • grade 3 >10mm translation
      • PCL may give false lachman test due to posterior subluxation
    • Pivot shift
      • extension, int rotation and then flexion
      • lateral tibia is subluxed anteriorly, when flexed to 30 degree spontaneously reduces- due to IT band changing from extensor to flexor moment at knee
      • mimics the actual giving way
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5
Q

What is seen on xray of ACL Iiagment injury?

A
  • Xrays
    • usually normal
      • Segong fx - avulsion fx of prox lateral tibia
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6
Q

What is seen on MRI of ACL injury?

A
  • tear best seen on Sagittal view
  • bone brusing occurs in > 1/2 acute ACL tears
    • middle 1/3 of LFC ( sulcus terminalis)
    • Posterior 1/3 of lateral tibial plateau
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7
Q

What is the tx for ACL?

A
  • Non operative
    • Physio and lifesyle modifications
      • low demand pts
      • increased meniscal damage linke dto
        • loss of meniscal integrity
        • freq of buckling episodes
        • level 1/11 activity- jumping, heavy manual labour

Operative

  • ACL reconstruction
  • younger more active ( reduces risk of chondral /meniscal injury)
  • prior acl repair
  • children
  • _ w assoc MCl injury_
    • allow mcl to heal then preform ACL recon
    • varus/valgus instability can jeopardise graft
  • w assoc Meniscal tear
    • preform mensical repair same time as ACL
    • increased healing rate when repaired together
  • w assoc Postlat corner injury
    • reconstruct same time as ACL or 1st as 2 stage revision
  • Ligament Repair- hgh failure rate
  • Revision acl reconstruction
    • failed prior acl recon
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8
Q

Describe the technique of acl reconstruction?

A
  • Femoral tunnel placement
    • sagittal plane
      • 1-2mm of rim bone between tunnel and post cortex of femur
    • coronal plane
      • at 9-10 o’clock position lateral wall- more horizontal graft
  • Tibial Tunnel placement
    • sagittal plane
      • centre of tunnel into joint should be 10-11mm infront of anterior border of PCL
    • Coronal plane
      • tunnel trajectory 75degree from horizontal
        • obtain by moving tibial starting point 1/2 between tibial tubercle and post medial edge of tibia
  • Graft placement
    • graft preconditioning- reduce stress relaxation by 50%
    • graft tensioning at 20N/40N no clinical outcomes
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9
Q

Which graft is used in acl reconstruction?

A
  • Bone patellar bone autograft
    • adv
      • pt own bone
      • most common source of graft
      • faster incorporation
      • less immune reaction
      • long hx of use
      • bone to bone healing
      • ability to rigidly fix at joint line
      • max load to failure =2600N (nor acl 1725N)
    • dis
      • highest incidence of ant knee pain 10-30%
      • Patella fx
      • Patella tendon rupture
  • Quadruple hamstring autograft
    • adv
      • smaller incision, less perio pain, less ant knee pain
      • fixation strength <bone>
        </bone><li>MAx load to failure =<strong> 4000N</strong>
        </li>

</li>
<li>reduced peak flexion strength at 3 yrs cf BPB</li>
<li>concern about hamstring weakness in female athletes-> increase rerupture</li>
</bone>
* Allograft
* useful in revisions
* longer incoportion time
* risk of disease transmission
* ? re-rupture in atheletes
* Graft preparation
* Radiation- >3Mrads to kill HIV ( however this reduces the structural/mechanical properties of the graft
* Freezing: destroys cells but no effect on strength

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10
Q

Describe the rehab post acl reconstruction?

A

Early post-op

  • immediate
    • Ice
    • Immediate WB- reduce patellofemoral pain
    • Full passive extension
  • Early rehab
    • exercises thay don’t place excess stress on graft
    • isometric hamstrng contractions at any angle
    • isometric quads and hamstring contraction
    • active knee motion 35-90 degrees flexion
    • emhasized close chain( foot planted ) excerises
    • svoid
      • isokinetic quads strengthening
      • open chain quads strenthening
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11
Q

What is the main complications of acl resconstruction?

A
  • Tunnel malposition
    • most common cause of failure = 70%
    • Femoral tunnel
      • vertical femoral tunnel placement ( coronal plane)
        • by starting tunnel at vertical position in notch = 12 o’clock lateral wall cf 9-10 o’clock
        • will -> rotational instability, identified by a positive pivot shift
      • Anterior tunnel placement ( sagittal plane)
        • -> knee that tight in flexion and loose in extension
        • caused by failure to clear residents ridge
      • Posterior tunnel placement
        • lax in flexion, tight in extension
  • Tibial tunnel malposition
    • _​_Anterior misplacement-> knee tight in flexion w impingment in extension
    • Posterior misplacement -> acl impinges with PCL
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12
Q

Name the other causes of acl reconstruction complications?

A
  • Indequate graft fixation
  • Tunnel osteolysis
    • tx w observation
  • Missed diagnosis
    • combined ACL, PLC injuries- failure to tx PLC_> failure of ACL
  • Overaggressive rehab
  • Infection
    • septic arthritis- satph aureus most common
    • urgent joint aspiration+ gram stain & culture
    • immediate athroscopic I&D
    • Can often retain graft w mutliple I&D and Antibiotics for 6 wks minimum
  • Loss of motion and arthrofibrosis
    • preop- ensure pt gained full rom be surgery
    • proper tunnel placement criticial to full rom
    • tx <12 wks aggressive Physio & serial splinting
    • tx >12 wks lysis of adhesions/MUA
  • Infrapatella contracture syndrome
    • increased knee stiffness post surgery
  • Patella tendon rupture
  • Patella fx
  • complex Regional Pain Syndrome
  • hardware failure
  • Late arthritis
  • local nerve irriatation- saphenous n
  • Cyclops lesion
    • fibroproliferative tissue blocks extension
    • click heard at terminal extension
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13
Q

What is epidemioogy and mechanism of PCL injuries?

A
  • 5-20% of all knee ligamentous injuries
  • mechanism
    • direct blow to proximal tibia with a flexed knee ( dashboard injury)
    • noncontact hyperflexion w plantar-flexed foot
    • hyperextension injury
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14
Q

What is the mechanism of PCL?

A
  • Primary restraint to posterior tibial translation
  • functions to prevent hyperflexion/sliding
  • isolated injuries cause the greatest instability at 90 degrees of flexion
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15
Q

Name associated injuries of PCL?

A
  • PCL and posterior lateral corner
  • Multiligamentous knee injury
  • knee dislocation
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16
Q

What is the prognosis of a PCL def knee?

A
  • PCL deficiency -> increased contact pressures in the Patellofemoral and Medial compartments of the knee due to varus alignment
  • contraverisal whether late patellar and MFC chondrosis will develop
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17
Q

Describe the anatomy of the PCL?

A
  • origin- Posterior tibial sulcus below the articular surface
  • inserts anteriomedial femoral condyle
  • broad, crescent shaped footprint
  • PCL is 30% larger than ACL
  • 2 bundles
    • anterolateral- tight in flexion
      • most important for post stability at 90degrees of felxion
      • ***NB PAL- PCL has AnteroLat bundle
    • posteromedial- tight in extension
  • Lies between 2 ligaments
    • ​Ligament of Humphrey and ligament of wrisberg ( post)
  • ​Middle Geniculate artery
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18
Q

Describe the classification of PCL injury?

A
  • based on posterior subluxation of the tibia relative to femoral condyles ( w knee at 90 of flexion)
  • Grade 1- partial
    • 1-5mm post tibial translation
  • Grade 2 complete isolated
    • 6-10 mm post tibial translation
  • Grade 3
    • >10mm post tibial translation
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19
Q

What is the presentation of a pt with PCL injury?

A

Symptoms

  • Posterior knee pain
  • instability

O/E

  • varus/valgus stress
    • laxity at 0 degrees = MCL/LCL & PCL injury
    • laxity at 30 degrees alone= MCL/LCL injury
  • Post sag sign- knees at 90 degrees
    • medial tibial plateau rests 10mm ant to medial femoral condyle
  • Post draw test- knee 90o post direct force applied and translation quantified- most accurate maneouver for dx PCL injury. abn >5mm translation
  • Dial test
    • >10 degrees ER asymmetry at 30o and 90o = PCL and PLC injury
    • >10 degrees ER asymmetry at 30 o only = PCL only
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20
Q

What is seen on imaging of PCL injury?

A
  • AP and supine lateral
  • Lateral stress view
    • apply stress to ant tibia w knee flexed to 70o
    • asymmetric post tibial displacement = PCL injury
  • MRI
    • cofirms dx
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21
Q

What is the tx of PCL injury?

A

Non operative

  • Protected WB & rehab
    • for grade 1 / 2 injuries
    • quads rehab w knee extensor strengthening
    • return sport 2-4 wks
  • Relative immobilisation in extension 4 wks
    • isolated grade 3 injuries
    • young adults/ bony injury- surgery
    • extension brace w limited daily rom

Operative

  • PCL repair of bony avulsion fx or PCL reconstruction
    • for combined injuries PCL+ACL +PLC
    • PCL grade 3 MCL/LCL, isolated grade 3 w bony avulsion, isolated PCL w unstable knee
    • ORIF for bony avulsion
    • Recon options
      • Tibial inlay vs transtibial methods
      • single bundle vs double bundle
      • autograft vs allograft
      • allograft used when mutilple lig to recon
        • achilles, bone patella bone, hamstring, anterior tibialis
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22
Q

What is the outcomes of pcl repair for bony avulsion and reconstruction?

A
  • Good results achieved w primary repair of bony avulsions
  • primary repair of midsubstance rupture not successful
  • Results of pcl recon ** less successful than ACL** and residual post laxity often exists
  • successful reconstruction depends on addressing concomitiant ligament injuries
  • no outcomes studies clearly support one recon technique over another
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23
Q

What is the tx of chronic PCL injuries?

A
  • High tibial osteotomy
    • consider medial wedge osteotomy to treat both varus maliagnment and PCL deficiency
    • Increasing the tibial slope helps reduce the posterior sag of the tibia
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24
Q

Describe the surgical techniques of PCL reconstruction?

A
  • Transtibial approach arthroscopic
    • standards portals & accessory posteriomedial portal
      • placed 1cm prox to joint line post to MCL
      • avoid injury to branches of saphenous n
      • postmedial corner of knee best visualises w 70o arthrocope thru notch or postermedial portal
      • transtibial drilline anterior to posterior
      • fix graft in flexion
      • risk injury to popliteal vessels
  • Open ( tibial inlay)
    • Posteromedial incision between medial head of gastronemius and semimebranosus
    • used for ORIF bony avulsion
    • screw fixation is within 20 mm of popliteal arrtery
  • Single bundle
    • arthroscopic or open
    • reconstruct anterolateral bundle
    • tension at 90o flexion
  • Double Bundle
    • Arthroscopic or open
    • Anterolateral bundle tensioned at 90 o flexion
    • postriomedial bundle tensioned in extension
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25
Q

Describe the rehab for PCL recon ?

A
  • POst op care
    • Immobilise in extension early and protect against gravity
    • early motion is prone position
  • Rehab
    • Focus on quads rehab
    • avoid resisted hamstring exercises ( hamstring curls)
    • as hamstring create a aposterior pull on the tibia which increases stress on the graft
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26
Q

What are the complications of PCL reconstruction?

A
  • Popliteal arrtery injury
    • risk when drilling tibial tunnel
    • lies just posterior to PCL insertion on the tibia, on separated by posterior capsule
  • Patellofemoral pain/arthritis
    • due to chronic PCL deficiency
27
Q

Describe the epidemiology of MCL tears?

A
  • MCL is primary and secondary valgus stabiliser of the knee
  • Most common injured ligament of knee
  • mechanism
    • vagus and external rotational force to lateral knee
    • direct blows -> complete disruption of MCL
    • rupture usually at femoral insertion, greatest healing rates
28
Q

What are the associated conditions of MCL tears?

A
  • ACL tears
    • comprise up to 95% of assoc injuries
      • 20% grade 1 MCL
      • 53% grade 2 MCL
      • 78% grade 3 MCL
  • Meniscal Tears
    • up to 5% isolatd MCL assoc M tears
  • Pellengri-Stieda Syndrome
    • calcification of medial femoral insertion site
29
Q

Describe the anatomy of the MCL?

A
  • Reists valgus and external forces of the knee
  • composed of 3 layers
  • static stabilisers
    • Superifical MCL
      • primary restraint to valgus stress
    • Deep MCL & post oblique ligaments
      • secondary restraint to valgus stress
  • Dynamic stabilisers
    • Semimembranous complex
      • consists of 5 attachments
      • vastus medialis
      • medial retinaculum
      • pes anserinus group
        • sartorius
        • Semitendinous
        • gracilis
  • Blood supply
    • Superior medial and inferior medial geniculate arteries
30
Q

Describe the classification of MCL injuries?

A
  • Grade 1
    • mild severity 1-4mm gaping
    • minimal torn fibres
    • no loss of ligamentous intregrity
  • Grade 2
    • moderate severity,
    • incomplete tearing of MCL
    • increased joint laxity
    • end point at 30 degrees of flexion,5-9mm gaping
  • Grade 3
    • Severe
    • complete disruption of ligament
    • gross laxity
    • no end point at 30 degrees of flexion, >10mm
31
Q

Describe the presentation of MCL injury?

A
  • Pop at time of injury
  • medial joint line pain
  • difficult walking due to pain

O/E

  • Tenderness along medial joint line
  • ecchymosis
  • knee effusion
  • valgus stress at 30 flexion- MCL grade 1-3 injury
  • valgus stressing at 0 degrees of knee extension = posteromedial capsule or cruciate injury
  • saphenous n exam
32
Q

What is seen on xrays of mcl injury?

A
  • in young pts = Stress view may show gapping thorough physel fracture
  • most normal
33
Q

What is seen on MRI of mcl injury?

A
  • Modality of choice
34
Q

What is the tx of MCL tears?

A
  • Grade I
    • NSAIDS, rest and Physio
      • quads set, SLR and hip adduction immedauately
      • cycling and progressive resistance as tolerated
      • return to play 5-7 days
  • Grade 1-2 ( if stable in valgus stress full extension)
    • Bracing, nsaids, physio
      • hinge knee for ambulation
      • grade 2 return to sport 2-4wks
      • grade 3 return to sport 4-8 wks
  • Grade 3
    • Operative
    • **Ligament repair vs reconstruction **
    • chronic injury reconstruction
35
Q

Describe the technique to repair MCL?

A
  • Medial approach to knee
  • ligament avulsions should be reattached w suture anchors in 30 degrees of flexion
  • interstitial disruption
    • anterior advancement of MCL to femoral and tibial origins
36
Q

Describe the complications of MCL repairs?

A
  • Loss of motion
  • Neurological injury
    • saphenous nerve ( between sartorius and gracilis)
  • Laxity
    • assoc w distal MCL injuries ( have less healing potential than proximal ones)
37
Q

Describe the epidemiology of LCL injuries?

A
  • Isolated injury extremely rare!!
  • 7-16% of all knee injuries combined with Lateral complex injuries
    • particulary posterolateral corner injury
  • Mechanism
    • Traumatic
      • most frequently result from MVA and athletic injuries
      • direct blow or force to WB knee
      • Excessive varus stress, external tibial rotation, and or hyperextension
38
Q

Describe the anatomy of the LCL?

A
  • Origin
    • lateral femoral epicondyle
    • posterior & proximal to insertion of popliteus
  • Insertion
    • Anterolateral fibular head
    • most anterior structure on proximal fibular
    • LCL-> Popliteofibular ligament-> biceps femoris
  • Blood supply
    • superolateral and inferiolateral Geniculate arteries
  • Biomechanics
    • primary restraint to varus stress at 5o (55%) and 25o (69%) knee flexion.
    • secondary restraint to posteriolat rotation w >50 o flexion
    • resists varus in full extension w ACL/PCL
    • Tight in Extension, loose in flexion
39
Q

Describe the lateral layers of the knee?

A
  • Layer 1= iliotibial tract, biceps, fascia
  • common peroneal nerve - between layers 1 &2
  • Layer 2= Patellar retinaculum, patellofemoral lig
  • Layer 3
    • Superifical: LCL, fabellofibular lig
  • inferior lateral geniculate artery runs between sup/deep layers
    • Deep: Arcuate ligament, coronary lig, Popliteus tendon, popliteofibular lig, capsule
40
Q

Describe the classification of LCL/PLC injuries?

A
  • Grade 1 =0-5mm lateral opening, minimal
  • Grade 2= 6-9mm lateral opening, partial
  • Grade 3 = 10> without end point, complete
41
Q

What is the presentation of pt with LCL injury?

A

Symptoms

  • Instability near full extension
  • difficulty ascending/descening the stairs
  • difficulty cutting or pivoting activities
  • Lateral joint line pain & swelling

O/E

  • ecchymosis and lateral joint line pain
  • Gait= hyperextension or varus lateral thrust
  • Common peroneal n injury occur w LCL/PLC
  • varus stress test
    • instability at 30o only= LCL
    • varus instability at 0o & 30o flexion= LCL + ACL +/or PCL
  • Dial test
    • ​Varus instability and increased tibial external rotation at 30o flexion = LCL +PLC
42
Q

What is seen on xrays of LCL tear?

A
  • Varus stress view- widening of joint space
43
Q

What is seen on MRI of LCL injury?

A
44
Q

What is the tx of LCL injury?

A
  • Isolated Grade 1/2 LCL
    • limited immobilisation, progressive ROM and functional rehab
      • return to sports 6-8wks
  • Grade 3 LCL/rotatory instability/postlat instability
    • Operative
    • LCL repair/reconstruction +/- PLC/ACL/PCL reconstruction
    • more favourable outcomes when injuries acute
45
Q

Describe the surgical approach to repair the LCL?

A
  • Lateral approach to the knee
    • between iliotibial band ( sup gluteal n) & biceps femoris ( scaiatic nerve)
    • incise facia between them to expose LCL insertion on fibular head
    • develop 2nd interval proximally to identify lateral femoral epicondyle
  • Repair avulsion using suture anchors
  • Direct suture repair for midsubstance tears
  • repair within 2 wks of injury
46
Q

What is the surgical technique to reconstruct LCL + PLC?

A
  • Lateral approach to knee
  • Single stranded graft - bone -patellar -bone for isloated lCL
  • fibular based reconstruction ( larsen technique)
    • hamstring graft passed thru bone tunnel in fibular head adn limbs crossed to create a fig of 8 which is then fixed to lateral femur
  • Transtibial double bundle technique
  • Anatomical reconstruction using bifid graft ( split achilles tendon)
47
Q

What are the complications of LCL repair?

A
  • Persistent varus or hyperextension laxity
  • Peroneal n injury
  • stiffness
  • hardware irritation
48
Q

Describe the epidemiology of PCL injuries?

A
  • Approx 7-16% knee ligament injuries are lateral ligamentous complex
  • isolated injuries of PLC rare
  • missed PLC injuries are common cause of ACL reconstruction failures
  • Mechanism
    • Blow to anteromedial knee
    • varus blow to flexed knee
    • contact/noncontact hyperextension injuries
    • knee dislocation
49
Q

What are the assocaited injuries of PLC ?

A
  • Common peroneal nerve (15-29%)
  • Vascular injury
50
Q

What is the anatomy of the PLC?

A
  • Static structures
    • LCL (most ant structure on fibular head)
    • popliteus tendon
    • Popliteofibular ligament
    • lateral capsule
    • arcuate ligament
    • fabellofibular ligament
  • Dynamic stabilisers
    • Biceps femoris ( inserts posterior aspect of fibula post to LCL)
    • Popliteus muscle
    • Iliotibial tract
    • lateral head of gastrocnemius
  • Function
    • ​Popliteus works synergestically w PCL to control external rotation, varus and posterior transalation
51
Q

What is the classification of PLC injuries?

A
  • Grade 1: 0-5mm lateral opening
  • Grade 2: 5-10 mm lateral opening
  • Grade 3: >10mm lateral opening
52
Q

What is the presentation of pt with PLC injury?

A
  • Instability symptoms when knee in full extension
    • difficult w reciprocating stairs pivoting, cutting

O/E

  • gait exam
    • varus thrust or hyperextension thrust
  • Varus stress
    • varus laxity at 0o = LCL & ACL or PCL injury
    • varus laxity at 30o= LCL injury
  • Dial Test
    • >10 ext rotation at 30 o only = PLC
    • >10o ext rotation at 30o & 90o= PLC & PCL
  • ​External rotation recurvatum
    • positive when lower leg falls into ext rotation & recurvatum when leg suspended by toes
  • Postlateral draw test
  • Reverse pivot shift test
    • knee at 90o and ext rotation & valgus force applied to tibia
    • as knee extended the tibia reduces w palpable clunk- posterior subluxed to reduced posiiton in extension
  • ​Peroneal nerve injury
    • ​altered sensation to dorsum of foot and weak ankle dorsiflexion
    • approx 25% of pts with peroneal n dysfunction
53
Q

What is seen on xrays of PLC injury?

A
  • Avulsion of fx of fibula ( arcuate ligament) or femoral condyle
54
Q

What is seen on MRI w PLC injury?

A
  • injury to LCL, popliteus, biceps tendon
  • in acute injury may see bone brusing of medial femoral condyle and medial tibial plateau
55
Q

What is the tx of a PLC injury?

A

Non operative

  • Immobilisation in full extension w protected weight bearing for 2 weeks
    • PLC grade 1/2
    • followed by functional rehab on quads strengthening w return to sport in 8 wks

Operative

  • PLC repair
    • only in isolated PLC injuries w bony/soft tissue avulsion
    • able to operate within 2 weeks
    • avulsion fx fibular - tx with screws
    • may need augment PLC w free graft
  • PLC reconstruction
    • used for most grade 3 isolated injuries
    • when repair is not possible or has poor tissue quality
    • Larsen technique- hamstring thru fibular head , limbs crossed in figure of 8
    • trans-tibial double bundle reconstruction
      • split achilles tendon graft
      • 1 limb fixed to fib head w bone tunnel & transosseous suture to reconstruct LCL
      • 2nd limb brought thru post tibia to reconstruct the popliteofibular lig
      • post op 4 week cast control Leg ER cf brace
      • outcome- better early tx, repair higher failure cf reconstruction
  • ​​PLC repair/recon. ACL & /or PCL reconstruction +/- HTO
    • PLC recon at same time to ACL/PCL to prevent early cruciate damage
    • High tibial osteotomy for those w varus mechanical alignment
    • rehab
      • protected WB for 4 weeks ( leg cast control EX r better than brace)
      • Begin Passive rom at 4 weeks - avoid arthrofibrosis
      • avoid active hamstring exercises as will stress PLC
      • full active extension allowed
56
Q

What are the complications of PLC surgery?

A
  • Arthrofibrosis
  • Missed PLC injury
    • failure to identify PLC injury combined with ACL will lead to failure of ACL reconstruction
  • Peroneal Nerve injury (15-29%)
57
Q

Describe the epidemiology of knee dislocations?

A
  • Rare injury
  • Most common 20-40 years
  • mechanism
    • High energy trauma
    • fall onto flexed and adducted knee
  • assoc conditions
    • post hip dislocations ( flexed knee/hip)
    • Open tibia-fibula fx
    • other fx about the knee and ankle
58
Q

Decribe the course of the common peroneal nerve?

A
59
Q

What is the classification ot proximal tibio-fibular dislocations?

A
  • Ogden
  • Subluxation &
  • 3 types of dislocation
    • anterolateral - most common
    • posteromedial
    • superior
60
Q

What is the presentation of a pt with proximal tibio-fibular dislocation?

A

Symptoms

  • Lateral knee pain
    • mimic a lateral meniscal tear
  • Instability

O/E

  • Tenderness over fibular head
  • comparison of bilateral knees with palpation of normal anatomical landmarks and relative positions
61
Q

What is seen on xray of a proximal tibio-fibular dislocation?

A
62
Q

What is the imaging modality of choice for proximal tibio-fibular dislocation?

A
  • CT
  • identifies presence or absence of dislocation
63
Q

What is the tx of proximal tibio-fibular dislocation?

A
  • Closed reduction
    • acute dislocations
    • flex knee 80-110 o ( relaxes LCL and biceps femoris tendon)
    • apply pressure over fibular head opposite to direction of dislocation
    • post reduction immobilisation in extension vs early rom is contraversial
  • Surgical soft tissue stabilisation vs ope reduction and pinning vs arthrodesis vs fibular head resection
    • ​for chronic dislocation w chronic pain adn symptomatic instability
64
Q

What are the complications of proximal tibio-fibular dislocation?

A
  • Recurrence
  • Common peroneal nerve injury
    • usually w posterior dislocations
  • Arthritis
    • rarely occurs & usualy minally symptomatic