MSK 8 - Lower Limbs 4 Flashcards
What is the popliteal fossa?
The popliteal fossa is a fat–filled diamond- shaped space located posterior to the knee joint. It is comparable to the ante-cubital fossa found in the upper limb
What is 1?
Biceps femoris
What is 2?
Semimembranosus
What is 3?
Semitendonosus
What is 4?
Tibial nerve
What is 5?
Popliteal artery
What is 6?
Common peroneal (fibular) nerve
What word is interchangable with fibular?
Peroneal
(not perineal)
What structures are found in the popliteal fossa?
- Biceps femoris
- Semimembranosus
- Semitendinosus
- Tibial nerve
- Popliteal artery
- Common peroneal nerve
What is the relationship between the popliteal vein and popliteal artery?
Popliteal artery is deep to vein
What muscles form the following boundaries of the popliteal fossa:
- superior
- inferior
- Superior boundary
- Medial - semimembranosus and semitendonosus tendons
- Lateral - bicep femoris
- Inferior
- Gastrocnemius
What are the contents of the popliteal fossa?
- Fat
- Posterior cutaneous nerve of thigh
- Tibial and common fibular nerves
- Popliteal artery and vein and their branches and tributaries
- Termination of small saphenous vein
- Popliteal lymph nodes and vessels
What is the popliteal artery a contuation of?
Femoral artery as it emerges from adductor hiatus
What compartment of the lower leg is the largest?
Posterior compartment
How can the muscles in the posterior compartment of the lower leg be divided?
Into superficial and deep group
How many heads does the gastrocnemius have?
2 heads
What nerve innervates the gastrocnemius muscle?
Tibial nerve (S1, S2)
What are the nerve roots of the tibial nerve?
S1, S2
What is the action of the gastrocnemius?
Dorsiflexion of ankle
What is the action of the plantasis?
Weakly assist gastrocnemius in plantarflexion of ankle, function is mainly proprioceptive
What is unsual about the plantaris?
Very long tendon
What are the superficial muscles of the posterior compartment of lower leg?
- Gastrocnemius
- Plantaris
- Soleus
What is A?
Medial head of gastrocnemius
What is B?
Lateral head of gastrocnemius
What is C?
Aponeurosis of gastrocnemius
What is D?
Soleus
What is E?
Plantaris
What is F?
Achiles tendon
What is the strong terminal attachment of the gastrocnemius called?
Achilles tendon
Where does the gastrocnemius insert?
As the achilles tendon onto the posterior aspect of calcaneous bone
What is 1?
Popliteus
What is 2?
Flexor halluces longus
What is 3?
Tibialis posterior
What is 4?
Flexor digitorum longus
What are the 4 muscles of the deep compartment of posteror compartment of lower leg?
- Popliteus
- Flexor halluces longus
- Tibialis posterior
- Flexor digitorum longus
How do the deep posterior muscles of the lower legs get to the sole olf the foot?
These muscles must pass to the sole of the foot, but do not travel around the calcaneus, where they would be compressed.
Rather they pass medially to enter through the ‘door to the foot’, posterior to the medial malleolus, covered by the flexor retinaculum
What is the action of the deep posterior muscles of the lower leg?
Flexion of toes and/or ankle
What nerve and vessel accompany the deep posterior muscles of the lower leg to the ‘door of the foot’?
- Tibial nerve
- Posterior tibial artery
Which nerve innervates all the muscles of the posterior compartment of the leg?
Tibial nerve (S1, S2)
Which branch of the popliteal artery supplies the posterior compartment of the leg?
Posterior tibial artery
What is A?
Tibial nerve
What is B?
Posterior tibial artery
What is C?
Common fibular nerve
What is D?
Anterior tibial artery
What is a rule of thumb about the course of the main motor nerves and sensory nerves of the lower legs?
- Generally
- Motor nerves follow arterial supply
- With some sensory nerves following venous supply
What are the functions of the foot?
The foot functions to support the body weight and plays an important role in locomotion.
What is 1?
Body of talus
What is 2?
Calcaneus
What is 3?
Navicular
What is 4?
Cuboid
What is 5?
Medial, intermediate and lateral cuneiform
What is 6?
Metatarsals 1-5
What is the deep fascia of the foot known as?
Plantar fascia
What are the functions of the investing fascia?
- Supporting arches of foot
- Acting as spring when pushing off in normal walking gait
How does plantar fascitis often present?
Plantar fasciitis is a common presenting condition, often felt as heel pain and is generally brought on by overuse (running) or increase in weight and/ or age.
What is treatment of plantar fascitis?
Treatment of this involves resting, strengthening exercises or invasive interventions such as steroid injection or as a last resort surgery.
What movements of the ankle are achieved at the mortise joint of the ankle?
Flexion and extension
What joints does movement of the ankle occur at?
- Mortise joint
- Flexion and extension
- Subtalar joints (those below talus) - talonavicular and talocalcaneal
- Exersion and inversion
What movements occur at the subtalar joint?
Inversion and eversion
What is 1?
Talonavicular joint
What is 2?
Talocalcaneal joint
What are the subtalar joints?
- Talonavicular joint
- Talocalcaneal joint
What movements occur at:
- talonavicular joint
- talocalcaneal joint
- Talonavicular joint
- Inversion and eversion
- Talocalcaneal joint
- Helps with process allowing for some lateral sliding movement
What kind of joint is the talonavicular joint?
Ball and socket synovial joint
What kind of joint is the talocalcaneal joint?
Plane type synovial joint
What are the 2 arches of the foot?
- Longitudinal arch
- Transverse arch
What are the fucntions of the arches of the foot?
- Distribute body weight on the main fat pads of food
- Act as shock absorber
Body weight tends to force what bones apart?
In the view of the foot below, see how the body weight acting vertically downwards on the talus will tend to force the navicular and calcaneus bones apart.
This force is resisted by many of the muscle tendons which cross these joints but also by some important ligaments. This is the plantar calcaneo-navicular or ‘spring’ ligament. It also helps to maintain the medial longitudinal arch and contributes to the subtalar joints.
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What ligament helps resist the force of body weight seperating the navicular and calcaneus bones apart?
Plantar calcaneo-navicular or spring ligament (also called)
What are the functions of the plantar calcaneo-navicular ligament?
- Resist body weight seperating navicular and calcaneus bones apart
- Maintain medial longitudinal arch
- Contribute to subtalar joints
What is the plantar calcaneo-navicular ligament also called?
Spring ligament
What is the integrity of the foot arches maintained by?
- Passive factors
- Shape of united bones
- Plantar spring ligament
- Long plantar ligament
- Short plantar ligament
- Dynamic factors
- Intrinsic muscles of foot
- Long flexor tendons
- Tendon of tibialis anterior and fibularis longus
What are some conditions of the arches in the foot?
High arches (pes cavus)
Flat feet (pes planus)
What are the 4 layers of the muscles in the foot?
- Immeditely deep to plantar fascia
- Flexors and neurovascular bundle
- Deep intrinsic muscles
- Interossei muscles
What is A?
Abductor digiti minimi
What is B?
Flexor digitorum brevis
What is C?
Abductor hallucis
What is D?
Flexor hallicus longus
What is E?
Flexor digitorum accessoris
What is F?
Lumbricals 1-4
What is G?
Lateral plantar nerve and artery
What is H?
Medial plantar nerve and artery
What muscles are immediately deep to the plantar fascia?
- Abductor digiti minimi
- Abductor hallucis
- Flexor digitorum brevis
What are the muscles in the 2nd layer of the plantar foot?
- Flexor hallicus longus
- Flexor digitorum accessoris
- Lumbricals 1-4
What is found in the neurovascular bundle in the 2nd layer of the plantar foot?
- Medial plantar nerve and artery
- Lateral plantar nerve and artery
What is the action of the first layer of plantar foot muscles?
Flexion of toes, initirating the first part of gait cycle (ground phase)
What are the terminal branches of the tibial artery and nerve?
- Tibial artery
- Medial plantar artery
- Lateral plantar artery
- Tibial nerve
- Medial plantar nerve
- Lateral plantar nerve
What does layer 3 (deep instrinsic muscles) of the foot contain?
The adductors and short flexors of toes
What does layer 4 of the foot muscles contain?
- Interossei
- Subdivided into plantar interossei which adduct
- and dorsal interossei which abduct digits
What can the interossei of the foot be subdivided into?
Plantar and dorsal interossei
What is the action of:
- plantar interossei
- dorsal interossei
- Plantar interossei
- Adduction of digits
- Dorsal interossei
- Abduction of digits