congenital pes planus Flashcards Preview

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Flashcards in congenital pes planus Deck (41):
1

What are the causes of congenital pes planus?

  • Calcaneovalgus foot
  • Accessory navicular
  • Tarsal coalition
  • Vertical talus
  • Flexible flatfoot

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2

What is calcaneovalgus ?

  • A soft tissue deformity characterised by
  • Excessive dorsiflexion HINDFOOT
  • HINDFOOT VALGUS
  • NO DISLOCATION/ bony deformity

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3

What is the aetiology of calcaneovalgus foot?

  • Uterine packaging
  • More common in females, first born

4

What is calcaneovalgus foot associated with?

  • Vertical talus
  • Posteriomedial tibial Bowing
  • Paralytic foot deformity
    • L5 spina bifida

5

What do you clinically see in a child with calcaneovalgus foot ?

  • Excessive Dorsiflexion of hindfoot
  • PASSIVELY CORRECTABLE
  • dorsal surface of foot rests on ant tibia
  • looks similar to vertical talus but nb this is rigid hindfoot, midfoot

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6

What is the pathoanatomy of calcaneovalgus foot?

  • Spasticity of
    • foot dorsiflexors/evertors L4/5
  • Weakness of
    • plantar flexors/invertors S1/2

7

What do you see on X-rays?

  • 1st metatarsal lines up with talus cf vertical talus when axis of talus is plantar to 1st metatarsal
  • postmedial tibial bowing

8

What is the treatment of calcaneovalgus foot?

Non operative

  • observation and passive stretching exercises
  • Resolves spontaneously

9

What is the complication of calcaneovalgus foot?

  • Limb length discrepancy due to posteriomedial bowing

10

Is an accessory navicular common?

What is the pathoanatomy of accessory navicular ?

  • 12% of population normal variant
  • occurs as a plantar medial enlargment of navicular bone
  • navicular ossify in girls 3, boys 5 the accessory navisular does not ossify prior to 8 years

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11

What are the symptoms of an accessory navicular?

  • Majority asymptomatic
  • MEDIAL ARCH PAIN=  worse with OVERUSE
  • TENDER- medial and plantar navicular
  • FLEXIBLE FLAT FOOT

12

What is the best X-ray to see the accessory navicular?

  • External oblique
  • ap / lateral
  • MRI can delineate insertion of tibialis post  tendon

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13

What is the tx of accessory navicular?

non operative

  • Restrict activity, shoe modification, analgesia
    • Majority asymptomatic by time of skeletal maturity
  • Cast immobilisation - ongoing pain, short time

Surgery

  • SURGICAL EXCISION OF ACCESSORY NAVICULAR.
    • resect bone flush to medial cuneiform.
    • May have to slpit tibalis post as navicular may be within it
  • TRANSFER POST TIBIALIS TENDON TO UNDERSURFACE OF NAVICULAR improve symptoms but not pes planus

14

What is the classification of pes planus ?

Type1-3 1= sesmoid within post tibialis tendon 2• separate a Crawley bone attached to native navicular 3= complete boney enlargement

15

What is this?

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  • Vertical talus
  • aka congential covex pes valgus
  • A rare disorder consisting of a irreducible dorsal dislocation of the navicular on the talus -> a rigid flat foot deformity

16

What is the pathoanatomy of vertical talus?

  • Rockerbottom deformity consists of
    • fixed hindfoot equinovalgus
      • due to contracture of Achilles tendon and peroneal tendons
    • Rigid midfoot dorsiflexion
      • 2ary to dislocated navicular
    • ​Forefoot abducted and dorsiflexed
      • ​contracture of EHL, EDL, Tib anterior

17

What is the genetics of vertcial talus?

  • 20% FHX

18

What are the associated conditions of vertcial talus?

  • Myelodysplasia- common
  • arthrogryposis
  • Diastematomyelia
  • chromosomal abnromalities

19

What is the prognosis of vertical talus?

  • Poor in untreated cases
  • significant disability

20

What are the signs of vertical talus?

Signs

  • Rigid foot deformity
    • fixed hindfoot equinovalgus
    • fixed midfoot dorsiflexion
    • forefoot abducted & dorsiflexed
  • talar head prominence on medial plantar arch

21

What is seen lateral xray  with vertical talus?

Lateral xray

  • vertical position of talus
  • dorsal dislocation of navicular
  • Mery's angle >20 degrees
  • forced plantar-flexion view= shows persistent dorsal dislocation of navicular

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22

What does the ap xray ahow?

  • valgus of the midffoot
  • Talocalcaneal angle >40o  , normal 20-40 degrees

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23

What is the tx for vertical talus?

Non operative

  • Preoperative serial manipulation & casting for 3 months
    • stretches soft tissue doesn't eliminate need for surgery
    • foot is placed in plantarflexion and inversion

 

24

Describe the surgical tx of verticlal talus?

  • Surgical release and talonavicular reduction and pinning
    • most cases
    • preformed at 6-12 months
    • involves talus release w lengthening of contracted dorsolat tendons- TA, peroneals
    • Talonavicular joint is reduced & pinned while reconstruction of calcaneonavicular ligament- spring
  • ​Minimal invasive correction
    • ​Serial casting to stretch dorsal structures & gradually reduce talonavicular joint
    • when reduced closed/open pin of TN joint
  • Talectomy
    • resistant cases

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25

How do you tell the difference betwen vertical and oblique talus?

  • talonavicular angle - see pic
  • in oblique talus- the talonavicular joint will reduce on plantarflexed xray

26

What is tarsal coalition?

  • Congential abnormality that leads to
  • fusion of tarsal bones
  • rigid flatfoot
  • result in a syndrome= peroneal spastic flatfoot

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27

Where are the common tarsal coalitions?

 

  • Calcaneonavicular
    • ​​most common
  • Talocalcaneal

28

What is the epidemiology of tarsal coalition?

  • incidence 1-6%
  • most found incidentally and are asymptomatic
  • age of onset
    • calcaneonavicular 8-12yrs
    • talocalcaneal 12-15 yrs

29

What is the pathoanatomy of tarsal coalition?

  • Mesenchymal segmentation -> coalition of tarsal bones
  • Coalition maybe
    • fibrous
    • cartilaginous
    • osseous
  • ​when subtalar joint is restricted by coalition->distal joints compensate
    • ​flattening of arch
    • valgus hindfoot
    • peroneal spasticity
    •  

30

What is tarsal coalition associated with?

  • Fibular hemimelia
  • Apert syndrome

31

What are ths symptoms and signs of tarsal coalition?

Symptoms

  • Pain worse on activity
  • calf pain- peroneal spasticity
  • recurrent ankle sprains

​signs

  • hindfoot valgus
  • forefoot abduction
  • Limited subtalar motion
  • Arch of foot doesn't reconsititute on tip toeing

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32

What imaging is good to view tarsal coalition?

Xrays

  • 45 degree oblique view
    • 'anteater sign'- see pic
    • gd for calcaneonavicular coalition
  • lateral 
    • talar beaking
    • sign of talocalcaneal coalition
    • result of limited subtalar  joint motion
  • Harris
    • irregular middle facet joint
  • CT
    • rule out additional coalition
  • MRI
    • identify fibrous/cartilagneous coalition

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33

What is the tx of tarsal coalition?

Non operative

  • Observation
    • asymptomatic
  • immobilisation in cast/orthotics
    • symptomatic pts

Surgery

  • Surgical resection of coalition and interpositional fat graft or extensor digitorium brevis
    • resistance cases of consx tx
    • if coalition <50%
    • 80% pain relief
  • Subtalar athrodesis
    • ​if coalition is >50%
  • ​Triple arthrodesis
    • fusion of subtalar, calcaneocuboid, talonavicular joints
      • advanced coalition that fails just resection

34

ddescribe the surgical technique for excision of tarsal coalition?

  • Approach
    • calcaneonavicular
      • oblique incision just distal to subtalar joint
    • Talocalcaneal
      • curved incision medial side of foot
      • develop interval between Flexor Digitorium Longus and NV bundle
  • Excise bar and leave defect 1cm in size
    • interpose EDB ( calcaneonavicular)
    • Interpose fat (talocalcaneal)
  • Calcaneal osteotomy can be added for valgus
  • BK cast NWB 3 /52

35

What is the flexible flat foot?

  • Physiological variant consiting of a
  • decrease in the medial longitudinal arch and valgus hindfoot and forefoot adbuction when weightbearing

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36

What is the pathoanatomy of flexible flatfoot?

  • generalised ligamentous laxity
  • 25% assoc with gastronemius-soleus contractures

37

What is the prognosis of flexible flatfoot?

  • Most of time resolves spontaneously

38

What is the classification of flexible flatfoot?

  • Hypermobile flexible pes planovalgus
    • familial
    • most common
    • generalised ligamentous laxity
    • usually bilateral
    • associated with accessory navicular
  • Flexible pes planovalgus with tight heel cord
  • Rigid planovalgus with tarsal coalition

39

Describe the signs and symptoms of flexible flatfoot?

  • usually asymptomatic
  • foot is flat only when standing, reconsitutes with toe walking , hallux dorsiflexion, or foot hanging
  • normal and painless subtalar movement
  • hindfoot corrects into valgus on tiptoes

40

What is seen on radiographs in flexible flatfoot?

  • Ap and lateral 
    • to rule out tarsal coalition
    • congential vertical talus
    • accessory navicular
  • lateral shows
    • meary's angle- apex plantar

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41

What is the tx of flexible flatfoot?

Non operative

  • Observation, stretching,shoewear modifications, orthotics
    • asymptomatic
    • counsel parents that arch will develop
    • atheletic support with soft arches or stiff soles may improve
    • orthotics don't change natural history of disease

Surgery

  • Achilles tendon & gastronemius tendon lengthening
    • painful flexible flatfoot with refractory symptoms with stretching
  • Calcaneal lengthening osteotomy
    • if symptoms continue
      • evans osteotomy

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