What do you call the common accessory bone of the talus?
why does it form?
Os trigonum. unfused posterior process (lateral tubercle)
What attaches to the posterior process of the talus?
Posterior talofibular ligament. It attaches to the lateral tubercle of the posterior process
What runs in the posterior process of the talus?
Tendon of FHL - between lateral and medical tubercles
What structure wraps directly under the sustentaculum?
What runs in the sinus tarsi? Name all structures.
Interosseous talocalcaneal ligament (cervical ligament)
artery of tarsal sinus
(artery of tarsal canal runs in the canal, which is the continuation of the sinus)
Describe the blood supply to the talus. What is the main supply?
all 3 terminal arteries:
posterior tibial a. (MAIN SUPPLY) - deltoid branch to BODY, artery of tarsal CANAL
dorsalis pedis a.--branch to dorsal head/neck, contributes to artery of tarsal SINUS
perforating peroneal a. - contributes to artery of tarsal SINUS - supply head/neck, lateral body
What is the Lisfranc ligament?
Interosseous portion of the oblique ligament from medial cuneiform to 2nd MT base
What are the components of the Lisfranc ligament? which is the strongest one? weakest?
Dorsal (weakest), plantar and interosseous (strongest)
What is the Chopart joint?
The midtarsal joint, comprising the talonavicular & Calcaneocuboid joints
What are the ligamentous components of the ankle syndesmosis?
Interosseous membrane (IoM)
Interosseous ligament (IoL)
Inferior transverse ligament (ITL) (really just the distal fibrocartilagenous component of the PITFL)
What are the components of the deltoid ligaments of the ankle?
Superficial: - Tibionavicular & Tibiocalcaneal
Deep: - Anterior & posterior tibiotalar
What is an Os Navicular? What are the types?
Accessory navicular. Type 1: Sesamoid within the distal part of the tendon
Type 2: Attachment to the posterior tibialis tendon, separated by synchondrosis
type 3: enlargement of navicular
What benign structure can often be confused with a Lisfranc Injury?
What is an os metatarsum?
Accessory bone found between the medial cuneiform and 1st/2nd metatarsals
What are the plantar layers of the foot?
1st: - Abductor hallucis brevis - Abductor digiti minimi - Flexor digitorum brevis , plantar fascia
2nd: - Quadratus plantae - Lumbricals , FHL and FDL tendons
3rd: - Flexor hallucis brevis - Flexor digiti minimi brevis - Adductor hallucis
4th: - Dorsal interossei - Plantar interossei (also tendons of per longus and tib post)
What are the muscles in the dorsal intrinsic compartment of the foot?
Extensor hallucis brevis Extensor digitorum brevis
What is the Master Knot of Henry? Why is it important?
which of the two structures is dorsal/volar?
Crossing between the FHL and FDL in the foot
Important as dividing it allows access to the deeper layers of the foot and because it can be a site of graft harvest (either FHL or FDL tendon transfers)
FHL is dorsal to FDL
What are the compartments of the foot and their key structures?
Calcaneal: quadratus plantae, posterior tibial NAV, lateral plantar NAV, +/- medial plantar nerve
Interosseous x4 - each has an interossei
Superficial: FDB, lumbricals, FDL tendons +/- medial plantar nerve
Medial: FHB, AbH
Lateral: AbDQ, FDM
What are the borders and contents of the tarsal tunnel?
Floor: medial talus, sustentaculum tali, medial calcaneal wall Roof: Lacinate ligament (flexor retinaculum) Contents: TP, FDL, PT artery, vein, Tibial nerve, FHL "Tom Dick And Very Nervous Harry"
What is Baxter's Nerve? What is it's clinical significance?
1st branch of the lateral plantar nerve It runs obliquely on top of quadratus plantae It's a cause of medial heel pain if impinged (dDx of plantar fascitis)
Where does the Plantaris tendon insert? be specific.
Medial to the achilles tendon. It may be a part of the achilles tendon but it will still be on the medial side
What structures combine to form the Sural Nerve?
Medial and lateral sural cutaneous nerves Lateral: branch of common peroneal nerve Medial: branch of tibial nerve
What does the Sural nerve run with? On which side is the nerve?
Runs with short saphenous vein and it is lateral to it
Where does the superficial peroneal nerve pierce the fascia and become subcutaneous?
10-12cm proximal to the tip of the lateral malleolus
What parts of the talus articulate with the calcaneus?
Anterior, middle and posterior articular surfaces
Describe the posterolateral approach to the Ankle:
Position: Prone or supine w/ large bump Incision: posterior border of fibula, centered around fracture
Plane: FHL (tibial) & peroneal muscles (sup. peroneal)
can also go anterior to peroneals depending on target anatomy
Dangers: Do not take off PITFL (devitalizes segments), Sural nerve
Describe the posteromedial approach to the ankle:
Position: supine Incision: 10cm longitudinal anteriorly curved incision Plane: pick optimal interval:
Tibialis posterior & flexor digitorum longus (both tibial) OR
FHL and NV bundle OR
FDL and NV bundle
Dangers: posterior tibial artery and vein, tibial nerve
Describe the anterior approach to the ankle:
Position: supine Incision: 15cm incision over ankle joint, between the 2 malleoli, beginning 10cm proximal to ankle joint Plane: EHL & EDL (both deep peroneal) Dangers: Superficial peroneal nerve, Neurovascular bundle
Where does the neurovascular bundle of the anterior compartment of the leg run above and below the ankle joint level?
Bundle includes deep peroneal nerve and anterior tibial artery
Above joint, runs between EHL and tib-ant. At the joint, crosses behind extensor hallucis longus then below, it runs between EHL and EDB (EDB is bit more medial than EDL)
What is the innervation of peroneus tertius?
Deep peroneal nerve