Dr. SREEKANTH THOTA

WINDSOR UNIVERSITYSCHOOL OF MEDICINE

DEPARTMENT OF ANATOMY

Lower limb

Muscle compartments in the thigh

• In the thigh, there are medial (adductor), anterior (extensor), and posterior (flexor) compartments.

Anterior Compartment of the Thigh• Muscles: Sartorius, iliacus, psoas, pectineus,

and quadriceps femoris• Blood supply: Femoral artery• Nerve supply: Femoral nerve

Anterior Thigh Muscles

• Anterior thigh muscles are the flexors of the hip and extensors of the knee.

SARTORIUS

• Origin : A.S.I.S.•Insertion : Upper medial surface of shaft of tibia• N. supply: Femoral nerve• Action :1.Flexion, abduction and Lateral rotation of thigh at hip joint. 2. Flexion leg at knee joint

ILIACUS

• Origin : Iliac fossa of hip bone

• Insertion : Along with psoas into lesser trochanter of femur

• N. supply: Femoral nerve

• Action :Flexes thigh on trunk

• Eg.: Sitting up from lying down

PSOAS

• Origin : Transverse process, bodies & I.V.D.’S of T12 & L 1-L5 vertebrae

• Insertion : Along with Iliacus into lesser trochanter of femur

• N. supply: Lumbar plexus

• Action : Flexes thigh on trunk

• Eg.: Sitting up from lying down

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T12

PECTINEUS

• Origin : Superior ramus of Pubis

• Insertion : Upper end of linea aspera of shaft of femur

• N. supply: Femoral nerve

• Action :Flexion, adduction of thigh at hip joint

QUADRICEPS FEMORIS

RECTUS FEMORIS :

• Origin : Straight Head: A.I.I.S Reflected Head: Ilium (Above Acetabulum)• Insertion :

Quadriceps tendon in to patella Via lig.patellae in to tibial tubercle •N. supply: Femoral nerve• Action : Flexion of thigh at hip joint•Extension of Leg at Knee joint

Patellar ligament

• The patellar ligament is the central portion of the common tendon of the Quadriceps femoris, which is continued from the patella to the tuberosity of the tibia.

VASTUS LATERALIS

• Origin : Upper end & shaft of femur

• Insertion : Quadriceps tendon in to patella via Lig.patellae in to tubercle of tibia

• N. supply: Femoral nerve

• Action : Extension of Leg at Knee joint

VASTUS MEDIALIS

• Origin : Upper end & shaft of femur

• Insertion : Quadriceps tendon in to patella Via Lig.patellae in to tubercle of tibia

• N. supply: Femoral nerve

• Action : Extension of Leg at Knee & Stabilizes Patella

VASTUS INTERMEDIUS• Origin : Anterior & lateral surface of shaft of femur

• Insertion : Quadriceps tendon in to patella Via Lig.patellae in to tubercle of tibia

• N. supply: Femoral nerve

• Action : Extension of Leg at Knee joint

Summary of Ant compt of thigh Muscle Movements

• Anterior compartment– Flexors of hip

• Sartorius (also abducts and laterally rotates hip and flexes and medially rotates knee)

• Iliopsoas • Pectineus (also adducts hip)

– Extensor of knee• Quadriceps femoris

– Rectus femoris (also flexes hip)

– Vastus lateralis – Vastus intermedius – Vastus medialis (also

stabilizes patella)

Patellar tendon reflex

• Tapping the patellar ligament with a hammer elicits the patellar tendon reflex (knee jerk)

• Tests the L2-L4 nerves• Diminution or absence—

result from interruption of innervation of quadriceps .

Medial compartment of thigh

• Blood supply: Profunda femoris artery and obturator artery.

• Nerve supply: Obturator nerve

Muscles: Gracilis, adductor longus, adductor brevis, adductor magnus, and obturator externus.

• Origin : Inferior ramus of Pubis & ramus of Ischium

• Insertion :Medial aspect of upper part of shaft of tibia

• N. supply: Obturator nerve

• Action : Adduction of thigh at hip joint Flexion of Leg at Knee joint

GRACILIS

ADDUCTOR LONGUS

• Origin : Body of Pubis, medial to pubic tubercle

• Insertion : Posterior surface of shaft of femur

• N. supply: Obturator nerve

• Action : Adduction of thigh at hip joint Assists Lateral rotation

ADDUCTOR BREVIS

• Origin : Inferior ramus of pubis

• Insertion : Posterior surface of shaft of femur

• N. supply: Obturator nerve

• Action : Adduction of thigh at hip joint Assists Lateral rotation

ADDUCTOR MAGNUS• Origin : Inferior ramus of pubis Ramus of ischium Ischial tuberosity (HAMSTRING PORTION)

• Insertion :Posterior surface of shaft of femur Adductor tubercle of femur (HAMSTRING PORTION)

• N. supply: Obturator + Sciatic nerves

• Action : Adduction of thigh at hip Assists Lateral rotation & Extension of thigh at hip joint

Adductor Hiatus

• The adductor hiatus is an opening or gap between the aponeurotic distal attachment of the adductor part of the adductor magnus and the tendinous distal attachment of the hamstring part.

• The adductor hiatus transmits the femoral artery and vein from the adductor canal in the thigh to the popliteal fossa posterior to the knee.

OBTURATOR EXTERNUS

• Origin : Outer surface of Obturator membrane Pubic & Ischial rami

• Insertion :Medial surface of greater trochanter

• N. supply: Obturator nerve

• Action : Lateral rotation of thigh at hip joint

Obturator nerve

• As the obturator nerve enters the thigh, it divides into two branches, an anterior branch and a posterior branch, which are separated by the adductor brevis muscle:

• Anterior branch: adductor longus, gracilis, and adductor brevis muscles, and often contributes to the supply of the pectineus muscle, and cutaneous branches innervate the skin on the medial side of the thigh.

• Posterior branch: obturator externus and adductor brevis muscles and the part of adductor magnus that attaches to the linea aspera

Obturator nerve

Obturator nerve

Deep artery of thigh (Profunda femoris artery)

• Branches :lateral and medial circumflex femoral branches and four perforating branches.

• Lateral circumflex femoral artery: 3 branches• 1. Ascending branch• 2. Descending branch• 3. Transverse branch• Medial femoral circumflex artery: It takes part

in the formation of the cruciate anastomosis.

Obturator Artery

• The obturator artery is a branch of the internal iliac artery.

• It gives off muscular branches and an articular branch to the hip joint.

Gluteal Region

• The gluteal region lies posterolateral to the bony pelvis and proximal end of the femur.

• Muscles in the region mainly abduct, extend, and laterally rotate the femur relative to the pelvic bone.

Ligaments of the Gluteal Region

• Sacrotuberous Ligament: sacrotuberous ligament connects the back of the sacrum to the ischial tuberosity

• Sacrospinous Ligament: sacrospinous ligament connects the back of the sacrum to the spine of the ischium.

Foramina of the Gluteal Region

• Greater Sciatic Foramen:The greater sciatic foramen is formed by the greater sciatic notch of the hip bone and the sacrotuberous and sacrospinous ligaments.

• It provides an exit from the pelvis into the gluteal region.

Lesser Sciatic Foramen:

• Formed by the lesser sciatic notch of the hip bone and the sacrotuberous and sacrospinous ligaments.

• It provides an entrance into the perineum from the gluteal region.

Nerves of the Gluteal Region

• Sacral Plexus:• The sacral plexus lies on the posterior pelvic

wall in front of the piriformis muscle .• It is formed from the anterior rami of the

lumbar nerves and the anterior rami of the sacral nerves.

Posterior wall of the pelvis

Branches

• Branches to the lower limb that leave the pelvis through the greater sciatic foramen .

• 1. Sciatic (L4, L5, S1, S2, S3): Articular branches to hip joint and muscular branches.

• It is the largest nerve in the body and consists of the tibial and common peroneal nerves bound together with fascia.

• Innervates all muscles in the posterior compartment of the thigh that flex the knee and all muscles that work the ankle and foot. llmusclein leg and foot

• 2. Superior gluteal (L4, L5, S1) : Gluteus medius and gluteus minimus muscles

• 3. Inferior gluteal (L5, S1, S2): Gluteus maximus

• 4. Nerve to obturator internus ( L5, S1, S2) : Obturator internus and superior gemellus muscles

• 5. Nerve to quadratus femoris (L4, L5, S1) : Quadratus femoris and inferior gemellus muscles

• 6. Posterior cutaneous nerve of the thigh(S2, S3) : Cutaneous branches to buttock and uppermost medial and posterior surfaces of thigh.

Branches to the pelvic muscles, pelvic viscera, and perineum:

• 1. Pudendal (S2, S3, S4) : Structures in perineum: sensory to genitalia; muscular branches to perineal muscles, external urethral sphincter, and external anal sphincter

• 2. Nerve to piriformis (S1, S2) : Piriformis muscle

Muscles of the Gluteal Region

• Muscles of the gluteal region are mainly in two groups:

1. Superficial group of larger muscles: Gluteus minimus, gluteus medius, and

gluteus maximus-and tensor fasciae latae.2. Deep group of small muscles: Piriformis, obturator internus, gemellus

superior, gemellus inferior, and quadratus femoris.

• Extensor of hip – Gluteus maximus (also helps in lateral rotation)

• Abductors of hip (help in Medial rotation)– Gluteus medius – Gluteus minimus– Tensor Fascia lata (also stabilizes knee in extension)• Function of all 3

– Contract to prevent sagging of unsupported side of hip during locomotion, enabling opposite foot to swing through (e.g., Trendelenburg test)

Muscles of Gluteal Region (Superficial group)

Gluteus maximus

• Origin : Outer surface of ilium, sacrum, coccyx, sacrotuberous ligament

Insertion :Iliotibial tract and gluteal tuberosity of femur

• N. supply:Inferior gluteal nerve

• Action :Extends and laterally rotates hip joint

Gluteus medius

• Origin : Outer surface of ilium Insertion :Lateral surface of

greater trochanter of femur• N. supply: Superior gluteal

nerve

• Action :Abducts thigh at hip joint; tilts pelvis when walking to permit opposite leg to clear ground

Gluteus minimus

• Origin : Outer surface of ilium

Insertion :Anterior surface of greater trochanter of femur

• N. supply: Superior gluteal nerve

• Action :Abducts thigh at hip joint; tilts pelvis when walking to permit opposite leg to clear ground

Positive Trendelenburg's sign

• If right gluteus medius and minimus muscles are paralyzed, the unsupported left side of the pelvis falls (sags) instead of rising; normally, the pelvis rises.

Tensor fasciae latae

• Origin : Iliac crest Insertion :Iliotibial tract

• N. supply: Superior gluteal nerve

• Action :Assists gluteus maximus in extending the knee joint

Deep group of small muscles

• Lateral Rotators of the Hip.• Small Muscles • Mostly attach near or on greater trochanter• All but one innervated by named nerves specific to

one or two of them The exception is the obturator externus – innervated

by posterior branch of obturator n.

PYRIFORMIS

• Origin : Anterior surface of sacrum;

sacrotuberous ligament

• Insertion : Upper border of Greater trochanter of femur

• N. supply: 1st & 2nd Sacral nerves

• Action : Lateral rotation of thigh at hip joint

OBTURATOR INTERNUS

• Origin : Inner surface of Obturator membrane

• Insertion : Upper border of Greater trochanter of femur

• N. supply: Nerve to obturator internus

• Action : Lateral rotation of thigh at hip joint

SUPERIOR GEMELLUS

• Origin : Spine of ischium

• Insertion : Upper border of Greater trochanter of femur

• N. supply: Nerve to obturator internus

• Action : Lateral rotation of thigh at hip joint

INFERIOR GEMELLUS

• Origin : Ischial tuberosity

• Insertion : Upper border of Greater trochanter of femur

• N. supply: Nerve to quadratus femoris (L5, S1)

• Action : Lateral rotation of thigh at hip joint

QUADRATUS FEMORIS

• Origin : Lateral border of ischial tuberosity

• Insertion : Quadrate tubercle of femur

• N. supply: Nerve to quadratus femoris (L5, S1)

• Action : Lateral rotation of thigh at hip joint

Nerves of the Gluteal Region

• 1. Sciatic Nerve: L4 to S3• 2. Posterior Cutaneous Nerve of the Thigh• 3. Superior Gluteal Nerve: L4 to S1• 4. Inferior Gluteal Nerve: L5 to S2• 5. Nerve to the Quadratus Femoris• 6. Pudendal Nerve:S2 to S4 • 7. Nerve to Obturator Internus

Intramuscular injections

• The safest place to inject is the upper outer quadrant of either gluteal region.

Arteries of the Gluteal Region

• 1. Superior Gluteal Artery• 2. Inferior Gluteal Artery

Posterior compartment of thigh

• Muscles: • Biceps femoris, semitendinosus,

semimembranosus, and a small part of the adductor magnus (hamstring muscles)

• Blood supply: Branches of the profunda femoris artery

• Nerve supply: Sciatic Nerve

Biceps femoris

• Origin : Long head: Ischial tuberosity• Short head: linea aspera, lateral

supracondylar ridge of shaft of femur• Insertion : Head of fibula• N. supply: Long head: tibial portion of sciatic

nerve Short head: common peroneal portion

of sciatic nerve

• Action : Flexes and laterally rotates leg at knee joint; long head also extends thigh at hip joint

Semitendinosus

• Origin : Ischial tuberosity• Insertion : Upper part of medial

surface of shaft of tibia• N. supply: Tibial portion of sciatic

nerve

• Action : Flexes and medially rotates leg at knee joint; extends thigh at hip joint

Semimembranosus

• Origin : Ischial tuberosity• Insertion : Medial condyle of

tibia• N. supply: Tibial portion of

sciatic nerve

• Action : Flexes and medially rotates leg at knee joint; extends thigh at hip joint

Adductor magnus (hamstring portion)

• Origin : Ischial tuberosity• Insertion : Adductor tubercle of femur• N. supply: Tibial portion of sciatic nerve

• Action : Extends thigh at hip joint

• Hamstrings• Together extend hip (except short head of

biceps femoris) and flex knee (except add mag)– Biceps femoris- (laterally rotates knee) – Semitendinosus- (medially rotates knee) – Semimembranosus- (medially rotates knee)

Posterior compartment

Blood Supply of the Posterior Compartment of the Thigh

• The four perforating branches of the profunda femoris artery provide a rich blood supply to this compartment