Anatomy: Anterior and Lateral Leg, Dorsum of Foot Flashcards
Tarsus
Bones of ankle/foot = Talus, Calcaneus, Cuboid, Navicular, Cuneiforms (3)
5 Metatarsals
Cuboid
Navicular
Cuneiforms (M, I, L)
Subtalar joint
between inferior surface of talus and superior surface of calcaneus - plane synovial joint.
Eversion and inversion.
Transverse tarsal joint
2 joints - Talocalcaneonavicular and calcaneocuboid, plane synovial joints
Standard location of surgical amputation of foot
transverse tarsal joint
Pens anserinus
Bursa location - tendons of semitendinosus, sartorius, Gracilis
Proximomedial aspect of tibia
Pes anserinus bursitis
The anserine bursa, along with its associated medial hamstring tendons, is located along the proximomedial aspect of the tibia. Pes anserinus bursitis is a common finding in patients and/or athletes who present with complaints of anterior knee pain. This condition is usually found in patients who have tight hamstrings, although it also can be caused by trauma (e.g., a direct blow). In most patients, pes anserine bursitis is a self-limiting condition that responds to a program of hamstring stretching and quadriceps strengthening.
Muscles of anterior compartment of leg
Tibialis anterior
Extensor hallucis longus
Extensor digitorum longus
Fibularis tertius
Dorsiflexion
A weaker movement than plantarflexion, but
important in elevating the forefoot to clear the ground in the swing phase of walking.
Most top of foot up (heel down)
Tibialis Anterior
Deep Fibular Nerve
Most medial and superficial dorsiflexor of anterior compartment. Lies on lateral surface of the tibia. It is the strongest dorsiflexor but also inverts the foot because of its attachment to the medial cuneiform and the base of the first metatarsal.
Anterior compartment and posterior tibial syndromes
Injury causes muscle expansion and swelling in a closed compartment; increased pressure causes loss of muscle and nerve function; this is an orthopedic emergency. a fasciotomy can be done to relieve the pressure in the compartment which would eventually cut off the blood supply and kill the muscles.
Shin splints are a mild compartment syndrome in anterior compartment (tibialis anterior sprain)
Extensor hallucis longus
Deep Fibular Nerve
Middle part of anterior fibular/io membrane –> dorsal aspect of distal phalanx of great toe
Extension of great toe, Dorsiflexion
Extensor Digitorum Longus
Deep Fibular Nerve
Lateral condyle of tibia/io membrane/superior 3/4 fibular –> 4 tendons into middle and distal phalanges of lateral 4 digits
Dorsiflexion of food, extension of lateral 4 digits
Fibularis tertius
Lower part of anterior fibula/io membrane –> dorsum of base of 5th metatarsal
(really part of EDL)
Deep fibular nerve
Dorsiflexion of foot and aids in eversion of foot
What n/a lie anteriorly to IOmembrane?
Anterior Tibial artery, deep fibular nerve
Deep Fibular nerve pathway
Branch of the Common Fibular nerve
Runs between EHL and Tibialis Anterior (so more medial)
Passes deep to Extensor Retinaculum on the lateral side of the dorsalis pedis artery
Divides into medial and lateral branches on dorsum of foot - becomes superficial at first webspace - 2nd/3rd dorsal digit nerves
Anterior Tibial artery pathway
The anterior tibial artery pierces and then runs on the interosseous membrane with the deep fibular nerve. Continues as dorsalis pedis on foot.
Superior extensor retinaculum
tibia to fibula above malleoli
Inferior extensor retinaculum
Y-shaped, loops around fibularis tertius and extensor digitorum longus from calcaneus.
Intrinsic muscles of dorsum of foot
extensor digitorum brevis
extensor hallucis brevis
* Originates from calcaneus and tendons –>
long flexor tendons of 4 digits (EDL)
dorsal aspect of proximal phalanx of great toe (EHL)
Deep Fibular Nerve
**Also 4 DABS (and 3 PADS) - all innervated by Lateral Plantar nerve
______ artery and _______ _______ nerve are found lateral to tendon of EHL
Dorsal artery and deep fibular nerve
Deep Fibular Nerve Entrapment
“Ski Boot Syndrome”
often caused by a tight ski boot or other type of shoe (also in sports with running). Produces pain in the dorsum of the foot and usually radiates to the web space between the 1st and 2nd toes. This is caused by compression of the deep fibular nerve deep to the inferior band of the extensor retinaculum and the extensor hallucis brevis. Associated with edema in anterior compartment of leg.
Anterior tibial artery becomes the ____________ once it passes the inferior extensor retinaculum. Terminates as ________. Gives off _______ artery –> _______
Dorsalis pedis artery
Terminates as the first dorsal metatarsal and deep plantar arteries
Gives off the arcuate artery (provides digital branches to the toes)
Dorsal Artery Pulse and clinical significance
Find just lateral to FHL tendon (on medial side dorsum of foot)
evaluated during a physical exam; a diminished or absent pulse suggests vascular insufficiency resulting from peripheral arterial disease. The P signs of peripheral arterial disease/arterial occlusion are: pain, pallor, paresthesia, paralysis, and pulselessness.
Lateral compartment innervated by
Superficial Fibular nerve
Muscles of Lateral compartment of leg
Fibularis longus
Fibularis Brevis
Actions of lateral compartment of leg
Eversion and weak plantarflexion.
Fibularis longus
Head/superior 2/3 fibular –> base of 1st metatarsal and medial cuneiform
Superficial fibular nerve
Eversion, weak plantarflexion
Fibularis brevis
lower part of fibula –> base of 5th metatarsal
superficial fibular nerve
eversion (less), weak plantarflexion
Fibularis longus tendon helps to support both the ________ and ______ arches of the foot during __________.
Fibularis longus tendon helps to support both the longitudinal and transverse arches of the foot during eversion.
Muscle responsible for inverting foot?
Tibialis posterior
Superficial Fibular Nerve
Superficial fibular nerve innervates the two muscles in the lateral compartment and then supplies cutaneous innervation to dorsum of foot.
Cutaneous branches on the foot become the 1st, 4th – 9th dorsal digital nerves. Dorsal digital 10 is termination of the sural nerve.
What vessel supplies blood to the muscles in lateral compartment?
Muscular branches from Fibular branch of Posterior Tibial artery
Injury to Common Fibular Nerve
Most commonly injured nerve in the body because of its superficial location against the head of the fibula
Foot-drop
a. Paralysis of all dorsiflexor and evertor muscles of the foot
b. Foot falls into plantarflexion when raised off the ground
Dermatomes
L4
L5
S1
S2
L4: Over top of knee –> medial foot
L5: side of leg –> dorsum/plantar of foot
S1: back of leg –> lateral side of foot
S2: back of leg (medial) –> inner arch of foot (not much)
_________ is the most important muscle for stability of knee joint
Quadriceps femoris
Patellar dislocation usually occurs ______ and is more common in _________
Laterally, women
Ligamentum patellae (patellar ligament)
- Continuation of quadriceps tendon
- From apex of patella to the tibial tuberosity
Fibular collateral Ligament
(round, cordlike)
- Extends from the lateral femoral condyle to the head of the fibula.
a. separated from joint cavity by the tendon of popliteus
b. Biceps femoris tendon split in two by this ligament
Tibial collateral ligament
(flat, broad)
Extends from the femoral condyle to the medial tibia above and below the condyle.
It is attached to the medial meniscus.
Sprains of these two ligaments (b,c) usually show pain near their attachments.
Knee most stable in ________ position
Fully extended (when tibial/fibular collateral ligaments taut)
Menisci
Crescentic plates of ________ that lie on the articular surface of the tibia-tibial plateau
They deepen the articular surface of the _____ for the _____
They are firmly attached to the _____________ around the periphery; they act as ____________
Tears of the menisci present as _________; a tear is usually _______
Crescentic plates of fibrocartilage that lie on the articular surface of the tibia-tibial plateau
b. They deepen the articular surface of the tibia for the femoral condyles
c. They are firmly attached to the articular cartilage around the periphery; they act as shock absorbers
d. Tears of the menisci present as tenderness at the joint line; a tear is usually surgically excised
(peripheral may repair or heal on own)
Where do meniscal tears heal best?
Meniscal tears that are peripheral can often be repaired or heal on their own because of the generous blood supply. Those that cannot be repaired or heal need to be removed.
Medial meniscus is attached firmly to _________
Tibial Collateral Ligament
C-shaped and firmly adherent to the deep surface of the tibial collateral ligament
Medial Meniscus
Circular, and separated from the fibular collateral ligament by the tendon of the popliteus muscle
Lateral Meniscus
Anterior/Posterior cruciate ligaments located _________
Within capsule but outside of synovial membrane
Anterior Cruciate
Weaker or Stronger?
- Prevents _____ displacement of the femur on the tibia (_______)
- Attaches to ______ ________ly
- ______ blood supply than PCL
Weaker
- Prevents posterior displacement of the femur on the tibia (hyperextension)
- Attaches to tibia anteriorly
- Poorer blood supply than PCL
Posterior Crucitate Ligament
Stronger or Weaker?
- Attaches to the ______ ______ly
- Tightens during _______ of the knee joint, preventing ______ displacement of femur or ______ displacement of tibia
Stronger of the two
- Attaches to the tibia posteriorly
- Tightens during flexion of the knee joint, preventing anterior displacement of femur or posterior displacement of tibia
Anterior Drawer Sign
Pull anteriorly on leg - test ACL
Main stabilizer of femur when walking downhill
PCL
Posterior Drawer Sign
Push posteriorly on leg - test PCL
newly discovered (2013). It is thought to stabilize the leg in rotation. It’s often torn when the ACL tears, but isn’t repaired. Consequently the knee can still give way.
Anterolateral ligament
Unhappy Triad
rupture of the tibial collateral ligament, often associated with tearing of the medial meniscus and anterior cruciate ligament
caused by blow to lateral side of knee
4 bursae communicate w/ synovial cavity of knee joint (extensions of synovium)
Suprapatellar bursa - quadriceps over distal femur
Politeus - between tenson of popliteus and lateral condyle of tibia
Gastrocnemius - Deep to origin of medial head of gastroc
Semimembranosus - between medial head of gastroc and insertion of semimembranosus
3 bursa that do not communicate w/ synovial cavity of knee joint
a. Subcutaneous prepatellar bursa
1. between skin and anterior patella
2. Prepatellar bursitis or “housemaid’s knee”
b. Subcutaneous infrapatellar bursa
1. between skin and tibial tuberosity
2. infrapatellar bursitis or “clergyman’s knee”
3. most commonly seen in roofers, carpet layers, floor tilers
c. Deep infrapatellar bursa
Most commonly injured joint in body
Talocrural joint - btween tibia, talus, fibula
Deltoid Ligament (4 parts)
Medial ankle ligaments
Anterior Tibiotalar
Tibionavicular
Tibiocalcaneal
Posterior Tibotalar
Pott’s Fracture
dislocation occurs when the foot is forcibly everted: pulls on strong medial ligament often avulsing the medial malleolus. Talus moves laterally shearing off the lateral malleolus or more commonly, breaking the fibula.
Lateral collateral ligament (3 parts)
Anterior Talofibular
Calcaneofibular
Posterior Talofibular
Inversion sprain
most common
Anterior talofibular most frequently sprained
Children’s ligaments are very ______ and their ankles are prone to _______ vs ________
Children’s ligaments are very tough and their ankles are more prone to fractures than sprains
A.Injury to this structure is demonstrated by the anterior drawer sign.
B.It prevents hyperextension of the knee.
C.It prevents the femur from sliding anteriorly on the tibia.
D.Rupture of this structure allows free rotation of the femur on the tibia.
E.When it ruptures, the tibia can slide anteriorly on the femur.
PCL - Prevents femur from sliding anteriorly on tibia (posterior dislocation of tibia on femur)
Eversion takes place at _____ joint
Subtalar
What muscle both dorsiflexes and inverts (supinates) foot?
Tibialis anterior
