The neuropathic foot

what are the common findings we see with neurogenic pain?

• pain referried in a dermatomal or cutnaeous distribution. but if its dermatomal we will also see changes in myotomes and DTR

• history of nerve injury, pathology, or mechanical compromise

• pain/symptom provocation with mechanical/movement tests

what are the two neuropathic foot pathologies?

tarsal tunnel syndrome

plantar neuropathy

what are the subjective findings for tarsal tunnel syndrome?

insiduous onset: often from overpronation that stresses the tibial nerve overtime

medial ankle/plantar foot burning, pain, paresthesia

numbness/weakness in the foot

worst after activity or at the end of the day

what are the objective findings for tarsal tunnel syndrome?

• limited ankle DF

• weakness in great toe extension, abduction, toe flexion

• decreased sensation in the plantar surface of the foot

• positive tinels sign

• positive straight leg raise

how would you differeniate between tarsal tunnel syndrome and someone with nerve root pathology or plantar fasciitis?

• nerve root: could do a lumbar screen or test DTR and they should be negative if it’s tarsal tunnel

• plantar fasciitis: will have a positive windlass test, will only see changes in sensation with tarsal tunnel, pain seen in the morning with plantar fasciitis versus the end of the day with tarsal tunnel, and will see a lot more ROM deficits with plantar fasciitis

what are the subjective findings for plantar neuropathy?

• insidious onset

• sharp, burning pain to the 3rd or 2nd websapce which can radiate to the toes

• sensation of “pebble in shoe”

• aggrivated with walking, running, wearing high heels, or narrow shoes

what are the objective findings for plantar neuropathy?

• decreased sensation distal 2/3’s of the plantar foot or distal 1/3 of the plantar foot

• tenderness to palpation of the 3rd or 2nd webspace

• positive squeeze test

• positive straight leg raise

how would you differentiate between plantar neuropathy and peripheral neuropathy?

• peripheral neuropathy is a result of error in messages getting down to the feet or hands which can lead to pain or changes in sensation

• we would see this bilaterally

• it will feel like a sock or glove pattern meaning there could be deficits on the surfaces of the feet or hands that a sock or glove would touch

• will commonly have a history of diabetes or chemotherapy

• will usually have global sensation loss

what is the goal of treatment here?

• to reduce nerve entrapment

what is some manual treatment we can do for tarsal tunnel?

• improve ankle DF through talocural distraction, posterior talocrural glide, DF mobilization with movement, distal tib fib posterior glides

• improve gastroc flexibility

• STM of tarsal tunnel region

• improve subtalar mobility

• improve tibial nerve mobility

what is some exercise and motor control treatments we can do for tarsal tunnel and plantar neuropathy?

• arch strengthening

• educate on how to use intrinsic muscles during functional tasks using cueing

• educate on where to put weight during functional activity

• hip strengthening

what is some manual treatment we can do for plantar neuropathy?

• metatarsal accessory mobility

• soft tissue mobilization in the MT region

• improve ankle DF

• improve 1st MTP extension

• improve tibial nerve mobility

what is the goal of a straight leg raise test and treatment?

test: to asses tissue resistance and symptom reproduction

treatment: to sensitize the tissue by moving joints that are two joints away so either cervical flexion or hip adduction

how can we bias peripheral nerves when doing the straight leg raise?

tibial nerve: ankle eversion and DF (TED)

sural nerve: ankle DF and inversion (SID)

fibular nerve: ankle PF and inversion (PIP or FIP)

what is the motor and sensory role of the tibial nerve and how can it become entraped?

motor: posterior leg compartment and plantar foot muscles

sensory: anterior 2/3s of the plantar foot and toes

MOI: eversion sprain, ankle fracture, TKA, increased load

what is the motor and sensory role of the common fibular nerve and how can it become entraped?

motor: anterior and lateral leg compartments

sensory: lower 2/3s of the lateral leg and dorsum of the foot

MOI: fibular head fracture, knee dislocation, tight leg cast

what is the motor and sensory role of the deep fibular nerve and how can it become entraped?

motor: anterior compartment

sensory: webspace between toes 1 and 2

MOI: fibular head fracture, knee dislocation, inversion sprain/fractures

what is the motor and sensory role of the superficial fibular nerve and how can it become entraped?

motor: lateral compartment of the leg

sensory: lateral leg and dorsum of the foot

MOI: fibular head fracture/trauma and knee dislocation

what is the motor and sensory role of the sural nerve and how can it become entraped?

motor: none

sensory: posterolateral aspect of the distal third of the leg and lateral aspect of the foot, heel, and ankle

MOI: trauma, calcaneal fracture, achilles repair surgery

what is the motor and sensory role of the saphenous nerve and how can it become entraped?

motor: none

sensory: medial knee, leg, and foot

MOI: adductor canal, knee surgery, vascular surgery

what is the motor and sensory role of the plantar nerves and how can it become entraped?

motor: intrinsic muscles of the foot

sensory: anterior 2/3s of the plantar foot and toes

entrapment sights: crossing of the FDL/FHL and 3rd/4th MTs