LEA Clinical of the Leg Flashcards
Common Fibular Nerve
- From sciatic nerve
- Passes around fibular neck
Common Fibular Nerve enters lateral compartment by
passing through posterior intermuscular septum
common fibular nerve bifurcates into what terminal branches
deep fibular
superficial fibular
deep fibular nerve passes through
anterior intermuscular septum to enter anterior compartment
common fibular nerve is susceptible to injury
- as it passes around fibula
- prolonged compression (from tight cast, sitting/sleeping position)
- trauma
injury to the common fibular is associated with
- Footdrop (increased tripping with gait) (b/c deep fibular)
- Weak dorsiflexion, toe extension, eversion
- Steppage gait
- Loss of sensation, distal anterolateral leg, dorsum of foot, 1st web space
broken fibula causes damage to
peroneal nerve (common fibular)
Which of the following have a footdrop associated with weakness with dorsiflexion? Common fibular nerve lesion? Deep fibular nerve lesion? Superficial nerve lesion? Sciatic nerve lesion? L4 spinal nerve lesion?
Common Fibular- yes Deep Fibular- yes Sciatic Nerve- yes L4 Spinal nerve- yes NOT Superficial nerve lesion.
Transmalleolar axis
Line passing between the center of the medial and lateral malleoli
relation to line passing through knee joint axis
Transmalleolar axis measures
tibial torsion
normal tibial torsion
children: -10 - 0 degrees
infants more negative, more internal rotation
Adults (reached by 8-10 yrs): 10-15 degrees external rotation
can obtain tibial torsion by measuring transmalleolar angle
Patient prone.
Line through the longitudinal axis of the thigh
and a line perpendicular to the most prominent point of the malleoli.
obtain tibial torsion by using thigh foot angle
Patient prone. Line bisecting foot and line bisecting thigh
Kager Triangle
Radiolucent (dark) triangle seen on lateral radiographs
Kagar Fat Pad
pre calcaneal, pre achilles fat pad
Obliterated Kager triangle
- Achilles pathology (tearing, inflammation)
- Calcaneal frx
- FHL tendon pathology
- Accessory soleus muscle
Boundaries of tarsal tunnel
- Medial: flexor retinaculum (laciniate ligament) and abductor hallucis
- Lateral: calcaneus, posterior talotibial and calcaneotibial ligaments
- Porta pedis is the distal margin of the tunnel
the porta pedis is the distal margin of
the tarsal tunnel
Tarsal Tunnel Syndrome
- Compressive neuropathy of tibial nerve or its branches within the tarsal tunnel
- porta pedis is also an entrapment site
tarsal tunnel syndrome causes altered sensation and pain over
medial and plantar foot, medial ankle (tibial nerve distribution)
tarsal tunnel syndrome can cause _____ with prolonged compression
Atrophy of intrinsic foot muscles
Tinel sign
- is present with tarsal tunnel syndrome
- pain with tapping, percussing the nerve in tunnel
Symptoms of tarsal tunnel syndrome reproduced with
sustained dorsiflexion of ankle and MTPJs and eversion of ankle;
Also can be reproduced with sustained plantarflexion and inversion.
treatment of tarsal tunnel syndrome
conservatively or surgically
Ankle Blocks
Used for procedures of the foot, pain relief, when a more local is not possible, etc
Ankle blocks avoid
- general anesthesia
- motor block of the leg muscles and sensory of the leg
- avoid releasing anesthesia into vessels, avoid puncturing nerves (anesthesia is released around the nerve)
landmarks are key with ankle blocks so ____ can be used to help
- ultrasounds
- nerve stimulators
Most of the foot is innervated by
nerves derived from the sciatic nerve, except 1 (saphenous)
5 nerves located at the ankle provide
- sensory innervation to the foot
- 3 superficial and 2 deep
3 superficial sensory nerves to the foot
- saphenous
- sural
- superficial fibular
2 deep sensory nerves to the foot
- posterior tibial
2. deep fibular
Posterior tibial nerve block
via the medial calcaneal branches, medial plantar, lateral plantar nerves
Plantar foot, medial heel, toe tips
sural nerve block
Lateral ankle, lateral heel, lateral foot, lateral 5th digit
deep fibular nerve block
1st web space
superficial fibular nerve block
most of the dorsum of the foot and toes
saphenous nerve block
medial foot
at the level of the malleoli which nerves are subcutaneous and which are deep to retinacula
-Saphenous, superficial fibular, sural are subcutaneous
-Deep fibular and posterior tibial are deep and become more superficial distally)
[-Where they are blocked depends on procedure]
Deep fibular nerve
deeply located at the ankle deep to deep fascia
landmarks of the deep fibular nerve
EHL, EDL, TA tendons, medial malleolus
perimalleolar: deep fibular nerve
lateral to EHL,
level of the superior aspect of medial malleolus
mid tarsal: deep fibular nerve
lateral to EHL, medial to dorsalis pedis artery pulse
Superficial fibular nerve landmarks
Subcutaneous between lateral malleolus and EHL tendon
perimalleolar: Superficial fibular nerve
between superior aspect of lateral malleolus and EHL
Anesthesia is administered in the area between the 2 landmarks
Perimalleolar: Sural Nerve
Subcutaneous, between Achilles tendon and superior aspect of lateral malleolus
(Anesthesia is administered between the 2 landmarks)
Perimalleolar: Posterior Tibial nerve
deep to the deep fascia, posterior to medial malleolus
Posterior Tibial Nerve is posterior to posterior tibial pulse where ?
midway between superior aspect of medial malleolus and Achilles tendon
Perimalleolar: Saphenous Nerve
subcutaneous
between TA tendon and medial malleolus
During a saphenous Nerve block ___ is nearby and can be punctured easily
Saphenous vein
body and sustentaculum tali
Tibia, talus, calcaneus
