tarsal tunnel syndrome

Question 1

What is being compressed by what in tarsal tunnel syndrome?

Answer 1

tibial nerve under the flexor retinaculum

*specifically it is the 1st branch of the lateral plantar n. (distal tarsal tunnel)

Question 2

what are some common etiologies of tarsal tunnel syndrome?

Answer 2

trauma- laceration, fractures/dislocation, blunt trauma
varicosities or other space-occupying lesions
heel varus
fibrosis
heel valgus
heel spur - causes distal tarsal tunnel compression

Question 3

What is the physical exam finding called for if teh paresthesias radiate proximally up the leg?

Answer 3

Valleix phenomenon

Question 4

What physical exam test can be used to clinically diagnose tarsal tunnel syndrome by putting my pressure on the nerve?

Answer 4

dorsiflexion-eversion test- maximally dorsiflexion the digits at the MPJ and evert the ankle to apply tension and compression to the tibial nerve.
will produce better Tinel’s sign also.

Question 5

what are some other DDx for neurolgoic conditions?

Answer 5

L5 or S1 radiculopathy (herniated disc)

sensory polyneuropathy

Question 6

what PE test could you do to rule in radiculopathy?

Answer 6

straight leg raise test (also called Lasegue’s sign)- patient is supine and examiner raises patient’s leg with knee straight.
positive sign for sciatica would be pain with cervical spine flexed, stretching the nerve roots

Question 7

what is teh flexor retinaculum aka?

Answer 7

laciniate ligament

Question 8

conservative treatment options for tarsal tunnel syndrome?

Answer 8

NSAIDs and corticosteroid injections to control inflammatio
orthoses
short leg cast or AFO
compression stockings for venous edema

Question 9

what muscle forms the roof of the porta pedis?

Answer 9

ABH

Question 10

what are the 3 components to surgical decompression of the tarsal tunnel?

Answer 10

1. release of the flexor retinaculum overlying the tarsal tunnel W/O deep suture closure
2. release the abductor fascia in teh porta pedis
3. release tibial nerve and associated plantar branches from surrounding entrapment

Question 11

for the distal tarsal tunnel syndrome, what nerve is involved?

Answer 11

1st branch of lateral plantar n.

• has motor innervation to ABDM, FDB, QP
• sensory innnervation to calcaneal periosteum, long plantar ligament

Question 12

clinically, how would you determine the entrapment of the 1st branch of the lateral plantar nerve?

Answer 12

compression over the medial aspect of the heel is more painful than plantar compression.
(why? this palpation pinches the nerve between the deep fascia of the ABH and medial margin of QP)

Question 13

Where does the impingement occur in distal tarsal tunnel syndrome?

Answer 13

where the nerve passes between the taut deep fascia of the ABH and medial margin of the medial head of QP

Question 14

what are the insertion sites for flexor retianculum?

Answer 14

medial malleolus to posterior inferior aspect of the calcaneal tuberosity

Question 15

conservative treatment approaches for tarsal tunnel syndrome?

Answer 15

NSAIDs
corticosteroid injections
orthotics
compressive stockings- if venous insufficiency 
short leg cast or AFO

Question 16

what is a surgical option for treatment for recurrent tarsal tunnel?

Answer 16

use of autogenous saphenous vein graft wrapping (enclosing the tibial n.) as a barrier technique