Muscles of the Lower Limb Flashcards
What are the main objectives of the lecture on muscles of the lower limb?
• Understand the organisation of fascia and compartments of the thigh/kūwhā and leg/waewae
• Discuss the muscles acting on the lower limb joints and their functions
What movements are associated with the hip joint?
• Flexion
• Extension
• Abduction
• Adduction
• Medial rotation
• Lateral rotation
What movements occur at the knee joint?
• Flexion
• Extension
• Medial rotation of flexed knee
• Lateral rotation of flexed knee
What are the movements associated with the ankle joint?
• Dorsiflexion
• Plantarflexion
What movements occur at the subtalar joint?
• Inversion
• Eversion
What movements are associated with the interphalangeal joints of the toes?
• Flexion
• Extension
List the tissue layers in the lower limb.
• Skin
• Superficial fascia (hypodermis)
• Deep fascia
• Muscle
• Bone
What is the function of the deep fascia in the thigh and leg?
• Decrease friction
• Aids venous return
• Forms intermuscular septa for compartments
What and where is the iliotibial band?
(thickened deep fascia-{fascia lata} of thigh on lateral side)
What and where is the Tensor fasciae latar?
Superficial muscle located on the superior lateral region of the thigh
The linear aspera (pointy region of femur bone) points to what compartment of the thigh?
Posterior
Where are the intermuscular septa in the thigh?
Lateral and medial
Where are the intermuscular septa in the leg?
Anterior and Posterior
What is the crural fascia
A thick connective tissue sheath that surrounds the muscles of the lower leg
What is the Retinaculum
Thickening of the deep fascia of the leg
Where is the Extensor retinaculum?
(Dorsum of leg/ankle)
* Superior
* Inferior
Where is the Fibular retinaculum?
(Lateral/fibular side)
* Superior
* Inferior
Where is the Flexor retinaculum?
(Medial ankle)
What is compartment syndrome?
Increase in pressure within a defined compartment of the limb, demarcated by fascia.
What are the functional groups of muscles acting on the lower limb?
• Muscles acting on the hip joint
• Muscles acting on the knee joint
• Muscles acting on the ankle joint
• Muscles acting on the subtalar joint
• Muscles acting on the toes
Name the hip flexor muscles.
- Psoas major
- Iliacus
- Psoas minor (if present)
- Rectus femoris
- Pectineus
- Sartorius
- Tensor fascia latae (TFL)
Where does the psoas major run?
from T12-L5 vertebral bodies to lesser trochanter
Where does the iliacus run?
From iliac fossa to lesser trochanter
What are the hip extensor muscles?
- Gluteus maximus
- Semimembranosus
- Semitendinosus
- Biceps femoris (long head and short head)
Which muscles are responsible for hip abduction?
• Gluteus medius
• Gluteus minimus
Where do the gluteus medius and minimums attach?
Both attach distally to
greater trochanter &
laterally placed
What is trendelenburg sign?
Contraction of gluteus medius and minimus
on the stance side prevents excessive pelvic
tilt/drop during the swing phase (single limb
stance) on the opposite side
List the hip adductor muscles.
- Pectineus
- Adductor longus
- Adductor brevis
- Adductor magnus
- Gracilis
Where is the adductor hiatus?
Between the adductor magnus and adductor tubercle
What muscles are involved in lateral rotation of the hip?
- Piriformis
- Gemellus superior
- Obturator internus
- Gemellus inferior
- Quadratus femoris
- Obturator externus
Which muscles are responsible for medial rotation of the hip?
• Gluteus medius
• Gluteus minimus
• Assisted by most adductors + TFL
What are the knee extensor muscles?
• Rectus femoris
• Vastus medialis
• Vastus intermedius
• Vastus lateralis
Which muscles are categorized as hamstrings?
• Semimembranosus
• Semitendinosus
• Biceps femoris (long head and short head)
What muscles are responsible for medial rotation of the knee?
Semitendinosus, Semimembranosus
What muscles are responsible for lateral rotation of the knee?
Biceps Femoris
What is the role of the quadriceps muscles?
They are responsible for knee extension.
True or False: The sartorius muscle is involved in knee extension.
True
Fill in the blank: The _______ is a thickening of the deep fascia of the leg that stabilizes tendons.
[retinaculum]
What is the anatomical term for the compartment of the thigh containing the adductor muscles?
Medial compartment
Which muscle assists in preventing excessive pelvic tilt during the stance phase?
Gluteus medius and minimus
What is the origin of the psoas major muscle?
From T12-L5 vertebral bodies to lesser trochanter
What is the insertion point for the iliacus muscle?
To lesser trochanter
What is the origin of the short head of the biceps femoris?
Line aspera
What are the distal attachments of the biceps femoris?
Medial tibial condyle, head of fibula
Which nerve innervates the posterior compartment of the thigh?
Sciatic nerve
Name the muscles that comprise the posterior compartment of the thigh.
- Semimembranosus
- Semitendinosus
- Biceps femoris (long and short head)
What are the main compartments of the thigh?
- Anterior compartment
- Medial compartment
- Posterior compartment
What are the muscles involved in dorsiflexion at the ankle joint?
- Tibialis anterior
- Extensor hallucis longus
- Extensor digitorum longus
Which muscles are responsible for plantarflexion at the ankle joint?
- Gastrocnemius
- Soleus
- Plantaris (if present)
- Tibialis posterior
- Flexor digitorum longus
- Flexor hallucis longus
Fill in the blank: The pes anserinus is located on the _______ tibial condyle.
medial
What is the mnemonic for the muscles of the deep posterior leg?
Tom Dick Harry
Which muscle is known as the ‘unlocking muscle of the knee’?
Popliteus
True or False: The popliteus muscle is a plantarflexor.
False
What is the primary function of the plantar aponeurosis?
- Protect deeper structures in the sole of the foot
- Support longitudinal arch of foot
- Stabilise skin
- Maintain shape of foot
What condition is characterized by irritation to the tendon sheath of the Achilles tendon?
Achilles tendonitis
Name the muscles that contribute to toe flexion.
- Flexor hallucis longus
- Flexor digitorum longus
Which muscles are involved in toe extension?
- Extensor hallucis longus
- Extensor digitorum longus
What are the main actions at the ankle joint?
- Plantarflexion
- Dorsiflexion
Which muscles participate in subtalar joint inversion?
- Tibialis anterior
- Tibialis posterior
Which muscles are responsible for subtalar joint eversion?
- Fibularis/peroneus longus
- Fibularis/peroneus brevis
What is the clinical significance of plantar fasciitis?
Biomechanical overuse from prolonged standing or running, creating microtears at the calcaneal enthesis
What are the main actions of the quadriceps muscle group?
Extension of the knee
Fill in the blank: The deep fascia of the thigh is known as _______.
fascia lata
What is the primary function of the deep fascia in the limb?
Decrease friction and aid venous return
Which muscles are involved in hip flexion?
- Iliacus
- Psoas major
- Rectus femoris
Which muscles are responsible for hip extension?
- Gluteus maximus
- Hamstrings
Name the two compartments of the leg.
- Anterior compartment
- Posterior compartment
- Lateral compartment
What is Haglund’s deformity?
Bony enlargement of posterior superior calcaneum
