Pes planus

Question 1

Who most likely to get it?

Answer 1

Women, 60th decade

Question 2

What is the aetiology ?

Answer 2

Multi factorial- 20% report acute injury

Tendon degeneration in watershed region- zone of hypo vascularity 2-6 cm from ptt attachment to navicular

Question 3

What do pt complain of?

Answer 3

Medial ankle/ foot pain and weakness
Progressive loss medial arch
Lateral ankle pain- subfibular impingement- late

Question 4

Clinical what do you see?

Answer 4

Pes planus
Hindfoot valgus- flexible 2, fixed 3-4
Forefoot abduction- too many toes
Rom- single heel raise- only in stage 1 
FIXED VS FLEXIBLE- passively correctable on plantigrade foot

Question 5

Where does tibialis post originate ?

Answer 5

Post tibia, fibula, intetosseus membrane

Question 6

Name the causes of pes planus?

Answer 6

CONGENTIAL- vertical talus, tarsal coalition, flexible flatfoot, accessory navicula, calcaneovalgus foot

ACQUIRED- of which most common is
Posterior tibial tendon dysfunction
Then inflammatory Arthropathy
Sero negative spondylioarthropathy

Question 7

What is tibialis posterior innervation?

Answer 7

Post tibial n L4-5

Question 8

What does tibialis posterior do after passing behind medial malleolus?

Answer 8

Splits into 3
Anterior- inserts navicular, medial cuneiform
Middle - inserts middle/ lat cuneiforms, cuboid mt2-5
Posterior - sustentaculum tail anteriorly

Question 9

What is tibialis posterior blood supply?

Answer 9

Post tibial artery distally- watershed 2-6 cm between navicular and distal medial malleolus

Question 10

What it is tibialis posterior function ?

Answer 10

Primary dynamic stabiliser of arch
Hindfoot inverter
Addicts and supinates forefoot during stance phase of gait
Secondary plantar flexor of ankle
Activation allows transverse tarsal joint to lock -> rigid lever arm for toe off phase of gait

Question 11

How would you investigate pes planus?

Answer 11

Wb ap and lateral radiographs?

Question 12

What angles would give you an idea?

Answer 12

Lateral talo first metatarsal angle- MEARY’s greater than 4 degrees - pes planus
Calcaneal pitch - te angle formed between the flat of the ground and the inf edge of the ground- less than 11 degrees loss in arch height - normal 12-35 degrees

Question 13

What is the diff with grade 2?

Answer 13

Broken down into 3 subgroups
2a
2b
2c

Question 14

Describe the findings amd tx of grade 2a?

Answer 14

Pes planus
Flexible hindfoot- <40 degrees o uncovering of talus
No able to single heel raise
X-ray arch collapse
Consx- Physio & afo- good results
Surgery - fdl transfer to navicular + medial slide Calcaneal osteotomy

Question 15

Describe the findings amd tx of grade 2b?

Answer 15

Flexible hindfoot and pes planus
FOREFOOT ABDUCTED- > 40 degrees uncovering - too many toes
No single heel raise
Arch collapse on X-ray
Tx- consx elderly orthotics as before
S= fdl transfer + lat column lengthening +/- medial Calcaneal osteotomy

Question 16

Describe the findings amd tx of grade 2c?

Answer 16

Pp
Flexible hindfoot 
Forefoot abducted
FIXED FOREFOOT SUPINATION
if stable medial column - navicular lines up with 1st mt= cotton osteotomy + fdl transfer, lat Column lengthenin ( dorsal open wedge cut to plantar flex 1st ray + medial side of calcaneous

Question 17

Describe the findings amd tx of grade 3?

Answer 17

FIXED RIGID HINDFOOT 
PP
FOREFOOT ABDUCTED
Pc - SEVERE SINUA TARSI PAIN
X-RAY- subtalar arthritis
Tx- TRIPLE ARTHRODESIS + TENDOACHILLES LENGTHENING

Question 18

Describe the findings amd tx of grade 4?

Answer 18

Same as three but
DELTOID LIG COMPROMISE
Pc- ANKLE PAIN+ sinus TARSI pain
X-rays - TALAR TILT IN ANKLE MORTICE, subtalar oa
T - if ankle valgus flexible- triple ARTHRODESIS , TAL and deltoid reconstruction but
If ankle rigid and oa subtalar- TIBIOTALOCALANEAL ARTHRODESIS

Question 19

What invokes A triple ARTHRODESIS ?

Answer 19

Fusion of
Subtalar
Calcaneocuboid
Talonavicular

Question 20

Describe the classification of posterior tibial dysfunction and tx options ?

Answer 20

Stage I
Tenosynovitis I X-ray changes 
Consx- wb cast 3-4 wks
            Orthotics - medial heel lift, longitudinal arch support all custom
Surgery- SYNOVECTONY