Leg Flashcards
anterior compartment of the leg
• Muscles – Tibialis anterior – Extensor digitorum longus – Extensor hallucis longus – Fibularis tertius • Nerve supply – Deep peroneal (fibular) nerve (L4-S1) • Bloodsupply – Anterior tibial artery
neurovascular bundle of the anterior compartment of the leg
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Retinaculae - Dorsal
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tib anterior transverse section
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tibialis anterior muscle type, insertion, origin, nerve supply, action
• Muscle type:
– Multipennate (from central tendon)
• Arises from:
– Upper 1/2 of lateral surface of the tibia & interosseous membrane
• Inserts:
– Passes through extensor retinacula to insert into medial cuneiform & base of 1st metatarsal
Note:
Has Tendon Sheath Through Retinacula
• Nerve Supply:
– Deep Peroneal (Fibular) Nerve (L4-L5)
• Action
– Dorsiflexes foot at ankle – Inversion
– Supports medial arch
extensor digiorum longus muscle type, attachments, nerve, action
• Muscle Type:
– Unipennate
• Arises From:
– Upper 2/3 Of Anterior Border Of Fibula & Interosseous Membrane
• Insertion:
– Tendon Passes Behind Superior & Through Inferior Retinacula, Splits Into Four & Inserts Into Extensor Apparatus & Distal Phalanx Of Each Lesser Digit
• Nerve Supply:
– Deep Peroneal (Fibular) Nerve (L5-S1)
• Action:
– Extends digits 2-5 at interphalangeal & metatarsophalangeal joints
– Synergist for dorsiflexion of foot at ankle
Note:
- Tendon Splits Into Four Slips
- Major Component Of The Extensor Apparatus
- Note Relationship With Peroneus Tertius (Later)
extensor hallucis longus
• Muscle Type
– Unipennate
• Arises:
– Middle 1/2 Of Anterior Border Of Fibula & Interosseous Membrane
• Inserts:
– Tendon Passes Deep To Superior & Through Inferior Retinacula To Insert Into Base Of Distal Phalanx of Hallux
• Nerve Supply:
– Deep Peroneal (Fibular) Nerve (L5-S1)
• Blood Supply:
– Anterior Tibial Artery
• Action:
– Extends hallux at interphalangeal & metatarsophalangeal joints
– Synergist in dorsiflexion of foot at ankle
Notes:
Muscle Is Positioned Laterally Yet Tendon Inserts Medially
peroneus tertius
Often regarded as part portion of EDL
Arises:
– Lower 1/4 of anterior surface of fibula & interosseous membrane
Inserts:
– Follows lateral tendon of EDL & inserts into base of 5th metatarsal
Nerve Supply:
– Deep Peroneal (Fibular) Nerve (L5-S1)
Action:
– Dorsiflexion of foot at ankle – Eversion of foot
Notes:
Considered To Be A Breakaway Part Of EDL
Sometimes Missing
Inserts Variably
dorsum of the foot
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deep peroneal nerve
Arises In body Of Peroneus Longus
Descends Deep To EDL With Anterior Tibial Artery.
Passes Beneath Retinacula To Appear In The Foot
• branches:
– muscular
• anterior compartment of leg • extensor digitorum brevis
• Dorsal interossei 1 & 2
– articular
• ankle joint
– sensory
• 1st cleft
popliteal artery
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lateral components of the leg
• Muscles
– Peroneus Longus – Peroneus Brevis
• Nerve Supply
– Superficial Peroneal (Fibular) Nerve (L5, S1, S2)
• Blood Supply
– Peroneal Artery
Superficial Peroneal (Fibular) Nerve
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peroneus longus
• Arises From:
– Head & Upper 2/3 Of Lateral Surface Of Fibula & Associated Fascia.
• Inserts:
– Passes Behind Lateral Malleolus (Beneath Peroneal Retinacula)
– Over Lateral Surface Of Calcaneus Below Peroneal Trochlea
– Enters peroneal sulcus on inferior Cuboid
– Crosses sole of Foot to Insert by Two Slips Into Base of 1st Cuneiform & 1st Metatarsal
• Nerve Supply
– Superficial Peroneal Nerve (L5, S1, S2)
• Action
– Plantarflexes foot at ankle – Everts foot
– Supports arches
Note:
- Common Tendon Sheath With P. Brevis Through Retinacula
- Frequently Has Sesamoid Bone In Peroneal Groove
peroneus brevis
• Arises From:
– Lower 2/3 Of Lateral Fibula
• Insertion:
– Passes Behind Lateral Malleolus (Beneath Peroneal Retinacula)
– Over Lateral Surface Of Calcaneus Below Peroneal Trochlea
– Inserts Into Base Of 5th Metatarsal.
• Nerve Supply:
– Superficial Peroneal Nerve (L5, S1, S2)
• Action:
– Eversion of foot
– Synergist in plantarflexion of foot at ankle
retinaculae lateral view
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posterior compartment of the leg
• Muscles
– Superficial
• Gastrocnemius (Two Heads) • Soleus
• Plantaris
– Deep
• Popliteus
- Flexor Hallucis Longus
- Flexor Digitorum Longus • Tibialis Posterior
• Nerve Supply
– Tibial Nerve (L4-S3)
• Blood Supply
– Posterior Tibial Artery
– Also Contains Peroneal Artery
gastrocnemius
• Arises:
– Medial Head Arises From Surface Of Femur Above Medial Condyle
– Lateral Head Arises From Lateral Condyle (medial Head Is Larger)
• Inserts:
– Into Posterior Aspect Of Calcaneus With Soleus - The Tendocalcaneus
• Innervation:
– Tibial nerve (S1-S2)
• Action:
– Plantarflex foot at ankle
– Flex leg at knee
soleus
• Arises:
– From Head & Upper 1/4 Of Fibula
– Soleal Line & Medial Border Of Tibia
– Interosseous Membrane
• Inserts:
– IntoPosteriorAspectOfCalcaneusWith Gastrocnemius
• Innervation:
– Tibialnerve(S1-S2)
• Action:
– Plantarflex foot at ankle
plantaris
• Arises:
– Lateral Supracondylar Line of femur
• Inserts:
– Long Tendon Passes Downwards & Medially Between Soleus & Gastrocnemius, Inserting Into Medial Edge Of Posterior Aspect Of The Calcaneus
• Innervation:
– Tibial nerve (S1-S2)
• Action:
– Plantarflex foot at ankle
– Flex leg at knee
tibialis posterior
Arises From:
– Posterolateral tibia
– Proximal half of fibula & Interosseous Membrane
• Inserts:
– Tendon Passes inferiorly posterior to Medial Malleolus Deep To Flexor Retinaculum
– Inserts Into navicular Tuberosity
– + All Other Bones In Tarsus Apart From Talus
• Nerve Supply
– Tibial Nerve (L4-L5)
• Action
– Inversion of foot
– Synergist in plantarflexion of foot at ankle
– Key in stabilising medial arch
flexor hallucis longus
• Arises From:
– Lower 2/3 Of Posterior Fibula & Associated Interosseous membrane
• Inserts:
– Passes Downwards Behind Medial Malleolus Deep To Flexor Retinaculum, Through Groove In Talus, Beneath Sustentaculum Tali
– Crosses FDL & runs along sole to distal phalanx of hallux
• Nerve Supply
– Tibial Nerve (S2, S3) • Action
– Flexes hallux (particularly toe-off phase of walking)
– Assists In Ankle Plantar Flexion
Note:
•Lateral Origin, Yet Medial Insertion
flexor digitorum longus
Arises From:
– Posterior Aspect Of Tibia Below Soleal Line
• Inserts:
– Tendon Passes Downwards Behind Medial Malleolus Deep To Flexor Retinaculum, Beneath Sustentaculum Tali & Into Foot.
– Crosses FHL, Divides Into Four Slips, One Passing Into Each Lesser Toe To Insert Into Distal Phalanx
Nerve Supply
– Tibial Nerve (S2, S3) • Action
– Flexes Lesser Toes, primarily
Note:
•Medial Origin, Yet Inserts Laterally
popliteus
Arises:
– Lateral femoral condyle
• Inserts:
– Posterior proximal tibia superior to Soleal Line
• Nerve Supply:
– Tibial Nerve (L4-S1)
• Action:
– Laterally rotates femur on fixed tibia. Important In The Knee Joint Unlocking Mechanism
posterior tibial artery
- Terminating Branch Of Popliteal (Is A Continuation Of)
- Arises At Level Of Lower Margin Of Popliteus Muscle
- Passes Downwards And Medially Between Soleus And The Deep Muscles (Deep To The Transverse Crural Intermuscular Septum)
- Passes Behind Medial Malleolus Into The Plantar Surface Of The Foot
peroneal (fibular) artery
Is A Branch Of The Posterior Tibial - Just Below The Popliteus Muscle
Descends Towards The Fibular On Or In Body Of Fhl.
Supplies Muscles In Posterior & Lateral Compartments
Terminates By Piercing Interosseous Membrane Into Dorsum Of Foot (Peroneal Perforating Pulse ~10%)