The muscles of the lower limb

Unlock Your Hip Flexors

Unlock Your Hip Flexors

Get Instant Access

Name of muscle

Position

Attachments

Action/s

Key facts

Quadriceps extensor

(quad-ri-seps eks-ten-sor) The quadriceps is made up of four muscles: rectus femoris, vastus lateralis, vastus intermedius, vastus medialis

Anterior aspect of the thigh

Attached to the pelvic girdle (rectus femoris) and femur (vastus group) at one end and to the patella and tibia at the other end

As a group they extend the knee and flex the hip

The quadriceps is a group of strong muscles used for walking, kicking and raising the body from a sitting or squatting position

Sartorius

(sar-tor-ee-us)

Crosses the anterior of the thigh

Attached to the ilium of the pelvis and the medial aspect of the tibia

Flexes the hip and knee and rotates the thigh laterally (turns it outwards)

Due to its unusual position, the sartorius can flex both the hip and the knee. Over contraction of the sartorius can lead to knee problems because turning the leg outwards puts pressure on the knee Sartorius is also the longest muscle in the human body

Adductors

(ad-duk-tors This is a group of four muscles:

adductor brevis, adductor longus, adductor magnus and pectineus

Situated on the medial aspect of the thigh

Attached to the lower part of the pelvic girdle at one end (pubic bones and the ischium) and the inside of the femur at the other end

As a group they adduct and laterally rotate the thigh

They also flex the hip

The adductors are important muscles in the maintenance of posture

Groin strains are common problems associated with these muscles

Gracilis

(gra-sil-is)

Long strap-like muscle

Attached to the lower edge of the pubic bone at one end and the upper part of the medial aspect of the tibia at the other end

Adducts thigh, flexes knee and hip, medially (inwardly) rotates the thigh and tibia

Gracilis muscle is the second longest muscle in the human body

Hamstrings

Consist of three muscles - two situated on the inside of the thigh (semitendinosus and semimembranosus) and one on the outside of the thigh (biceps femoris)

Posterior aspect of the thigh attaches to the lower part of the pelvis (ischium) and the lower part of the posterior of the femur to either side of the posterior of the tibia

Flex the knee and extend the hip

The hamstrings contract powerfully when raising the body from a stooped position and when climbing stairs

The muscles of the lower limb 131

Name of muscle

Position

Attachments

Action/s

Key facts

Tensor fascia latae (ten-sor fash-ee-a la-tee)

Runs laterally down the side of the thigh

Attached to the outer edge of the ilium of the pelvis and runs via the long fascia lata tendon to the lateral aspect of the top of the tibia

Flexes, abducts and medially rotates thigh

Attached to a broad sheet of connective tissue (fascia lata tendon), which helps to strengthen the knee joint when walking and running

Gastrocnemius

(gas-trok-nee-me-us)

Large superficial calf muscle with two bellies (central portion of the muscle) on the posterior of the lower leg

Attached to the lower aspect of the posterior of the femur across the back of the knee and runs via the Achilles tendon to the calcaneum at the back of the heel

Plantar flexes the foot and assists in knee flexion

Provides the push during fast walking and running

Soleus

(so-lee-us)

Deep in the gastrocnemius in the calf

Attached to the tibia and fibula just below the back of the knee at one end and runs via the Achilles tendon to the calcaneum at the other end

Plantar flexes the foot

A thicker and flatter muscle than the gastrocnemius and accounts for the contours of the gastrocnemius being so visible

Tibialis anterior (tib-ee-a-lis an-tee-ri-or)

Anterior aspect of the lower leg

Attached to the outer side of the tibia at one end and the medial cuneiform

Dorsiflexes and inverts the foot

If the tibialis anterior muscle becomes weak, it can lead to the lower leg rolling inwards due to the collapse of the medial longitudinal arch of the foot

Tibialis posterior

(tib-ee-a-lis pos-tee-ri-or)

Posterior aspect of the lower leg, very deeply situated in the calf

Attached to the back of the tibia and fibula at one end and to the navicular, third cuneiform and second, third and fourth metatarsals at the other end

Assists in plantar flexion and inverts the foot

Weakness in this muscle can cause the feet to turn out from the ankles rather than the knees. This causes the muscle to stretch and the medial longitudinal arch of the foot to drop

Peroneus longus/brevis

(pero-knee-us long-us)

Situated on the lateral aspect of the lower leg

Attach to the fibula to the underneath of the first (longus) and fifth metatarsal (brevis)

Plantar flexes and everts the foot

Going over on to the outside of the ankle, as in a trip or a fall, can sprain the peroneal muscles in the lower leg. If the injury is not treated properly it can affect future stability of the ankle joint

Flexor digitorum longus (fleks-

or dij-i-toe-rum long-us)

Medial to the tibialis anterior muscle

Extends from the middle third of the posterior of the tibia to the plantar surface of the second to fifth toes

Flexion of the toes, plantar flexion and inversion of the foot

Flexor and extensor muscles of the lower leg can become weak due to excess pressure and overuse in walking and running

Flexor hallicus longus

(fleks-or hal-oo-sis long-us)

On the outer side of the lower leg, towards the back of the lower leg

Extends from the distal two-thirds of the posterior fibula to the plantar surface of the big toe

Flexion of big toe, plantar flexion and inversion of foot

See above

(Continued )

Name of muscle

Position

Attachments

Action/s

Key facts

Extensor digitorum longus (eks-ten-sor long-us)

Lateral to the tibialis anterior muscle

Extends from the proximal two-thirds of the anterior of the fibula to the dorsal surface of the second to fifth toes

Extension of second to fifth toes, dorsiflexion and eversion of foot

See above

Extensor hallicus longus

(eks-ten-sor hal-oo-sis long-us)

Runs down the anterior of the lower leg

Extends from the middle third of the anterior of the fibula to the dorsal surface of the big toe

Extension of big toe, dorsiflexion and inversion of foot

See above

Superficial muscles

Deep muscles

Iliopsoas Tensor Fascia Lata Pectineus

Adductor longus

Rectus femoris

Gracilis

Sartorius

Peroneus longus

Extensor digitorum longus

Tibialis anterior

Iliopsoas Tensor Fascia Lata Pectineus

Adductor longus

Rectus femoris

Gracilis

Sartorius

Peroneus longus

Extensor digitorum longus

Tibialis anterior

Pectineus

Vastus intermedius

Adductor brevis

Vastus lateralis

Peroneus longus

Deep muscles

Pectineus

Vastus intermedius

Adductor brevis

Vastus lateralis

Peroneus longus

Muscle Anatomy And Physiology Exam

Adductor longus (cut)

Adductor magnus

Vastus medialis

Rectus femoris

Tibialis anterior

Extensor hallucis longus

Extensor digitorum longus

Adductor longus (cut)

Adductor magnus

Vastus medialis

Rectus femoris

Tibialis anterior

Extensor hallucis longus

Extensor digitorum longus

Fig 4.10 The muscles of the anterior of the lower limb

The muscles of the pelvic floor 133

Was this article helpful?

0 0
5 Common Skin Problems Answered

5 Common Skin Problems Answered

Our skin may just feel like a mere shield that protects us from the world outside. But, the fact is, its more than just the mask that keeps your insides in. It is a very unique and remarkable complex organ that reflects our general health.

Get My Free Ebook


Post a comment