[MSK] Anterolateral/ Medial Thigh 3.1 (Anterolateral Thigh Muscles and Innervations No Pics)

Iliopsoas

Iliacus and Psoas Major Complex

Iliacus and Psoas (Iliopsoas)

Located on either side of the spine, passes beneath the inguinal ligament in the groin, and attaches to the lesser trochanter

Iliacus and Psoas (Iliopsoas)

Only muscle with attachments at the vertebral column, pelvis, and femur

Iliacus and Psoas (Iliopsoas)

Main, most powerful flexor of the hip and an important flexor of the trunk

Iliacus and Psoas (Iliopsoas)

Important for flexing trunk against gravity (during sit-ups)

Iliacus and Psoas (Iliopsoas)

Contracts during sit-ups

Iliacus and Psoas (Iliopsoas)

Also functions as postural muscle

Iliacus and Psoas (Iliopsoas)

Maintains lordotic curvature of lumbar spine in standing (compensatory thoracic kyphosis)

Lesser trochanter of femur

Insertion of Psoas Major (Iliopsoas)

Anterior rami of lumbar nerve

Innervation of Psoas Major (Iliopsoas)

Psoas Major (Iliopsoas)

Inserts in Lesser trochanter of femur, Innervated by anterior rami of lumbar nerve

Psoas Major (Iliopsoas)

For flexion of thigh and trunk at the hip, Maintenance of posture, and Concentric contraction

Psoas Major (Iliopsoas)

Initiate forward swing (flex hip → Lift leg)

Iliacus (Iliopsoas)

From iliac crest, iliac fossa, ala of sacrum, and anterior sacroiliac ligaments

Lesser trochanter of femur

Insertion of Iliacus (Iliopsoas)

Iliacus and Psoas (Iliopsoas)

Inserted to Lesser trochanter of femur

Femoral nerve

Innervation of Iliacus (Iliopsoas)

Iliacus and Psoas (Iliopsoas)

For flexion of thigh and trunk at the hip and Maintenance of posture

Tensor fasciae latae

Enclosed by fascia lata

Tensor fasciae latae

Flexor of thigh

Tensor fasciae latae

Has superior gluteal artery

Tensor fasciae latae

Helps stabilize the extended knee against lateral swaying

Tensor fasciae latae

Helpful for standing inside a train

Tensor fasciae latae

Stabilizes of the hip by holding the femoral head within the acetabulum

Tensor fasciae latae

Assisted by the gluteus maximus in stabilizing the hip

Tensor fasciae latae

From Anterior superior iliac spine and Iliac crest

Tensor fasciae latae

Inserted to iliotibial tract, which itself inserts into the lateral condyle of the tibia (Gerdy tubercle)

Tensor fasciae latae

Innervated by superior gluteal nerve

Superior gluteal nerve

Innervation of Tensor fasciae latae

Tensor fasciae latae

For Flexion of thigh, Abduction, Medial/ Internal rotation of thigh, Stabilize hip by holding acetabulum and extended knee against lateral swaying

Iliacus and Psoas (Iliopsoas)

Tested clinically by having the patient flex their thigh at the hip against resistance while flexing their knee joint (also useful for diagnosing appendicitis)

Iliacus and Psoas (Iliopsoas)

Flex against the appendix and cecum

Pectineus

Transitional muscle between the anterior and medial compartments

Pectineus

Transitional muscle between the anterior and medial compartments

Pectineus

Although largely innervated by the femoral nerve, it is unusual in that it also participates in adduction of the thigh

Pectineus

One of the muscles that forms the floor of the femoral triangle

Pectineus

Superficial to this muscle is the femoral canal

Pectineus

Has dual innervation: Femoral and Obturator nerve

Femoral nerve

Pectineus main anterior nerve

Obturator nerve

Pectineus main adductor nerve

Pectineus

Inserted to pectineal line of femur

Pectineus

Innervated by both Femoral and Obturator nerve

Femoral, Obturator nerve

Innervation of Pectineus

Pectineus

For Adduction, Flexion of the thigh at the hip; Assists with medial/ internal rotation of thigh

Pectineus

Assists with medial/ internal rotation of thigh

Sartorius

Known as tailor’s muscle

Sartorius

Tailor’s sit cross-legged with the heel on the other leg when sewing activating this muscle

Sartorius

Most superficial muscle in the anterolateral compartment passing lateral to medial

Sartorius

Crosses and acts across two joints (hip and knee)

Sartorius

Longest muscle in the body but still not a strong muscle

Sartorius

Acts synergistically with other more powerful muscles

Sartorius

From end of anterior superior iliac spine

Sartorius

Inserted to Superior/ Upper portion of medial side of tibia

Pectineus, Sartorius, Quadriceps femoris (Rectus femoris, Vastus lateralis, Vastus intermedius, Vastus medialis)

Innervated by Femoral nerve

Femoral nerve

Innervation of Sartorius

Sartorius

For Hip flexion, Hip abduction, and Hip lateral rotation of thigh, and Flexion of leg at knee joint

Quadriceps femoris (Rectus femoris, Vastus lateralis, Vastus intermedius, Vastus medialis)

One of the most powerful muscles in the body

Quadriceps femoris (Rectus femoris, Vastus lateralis, Vastus intermedius, Vastus medialis)

Covers bulk of the anterior thigh

Quadriceps femoris (Rectus femoris, Vastus lateralis, Vastus intermedius, Vastus medialis)

Great extensor of the leg

Quadriceps femoris (Rectus femoris, Vastus lateralis, Vastus intermedius, Vastus medialis)

Attach to the superior pole of the patella

Medial/ Lateral Patellar Retinacula

Maintains patellar alignment

Medial/ Lateral Patellar Retinacula

Reinforces joint capsule

Patellar ligament

Continuation of the quadricepts tendon distally

Patellar ligament

From inferior pole of the patella to the tibial tuberosity

Patella

Also known as the knee cap

Patella

Largest sesamoid bone in the body

Sesamoid

Bones that develop within tendons

Patella

Bony connection between the quadriceps tendon superiorly and the patellar tendon inferiorly

Patella

Provides additional leverage for the quadriceps in placing the tendon more anteriorly

Patella

Allows the tendon to approach the tibia from a position of greater mechanical advantage

Rectus femoris

The only muscle in the quadriceps femoris that spans the hips and the knee

Rectus femoris

Extends the knee and Secondarily flexes the hip

Rectus femoris

May be susceptible to injury when attempting a kick

Rectus femoris

Also known as the kicking muscle

Vastus lateralis, intermedius, medialis

Vastus Muscles

Vastus lateralis

Largest of the quadriceps

Vastus lateralis

Lies on the lateral side of the thigh

Vastus intermedius

Found deep to the rectus femoris

Vastus medialis

Covers the medial side of the thigh

Rectus femoris

From the Anterior inferior iliac spine and Ilium of the pelvis

Vastus lateralis

From the Greater trochanter and Lateral lip of linea aspera of femur

Vastus intermedius

From Anterior and lateral surfaces of femoral shaft

Vastus medialis

From Intertrochanteric line and Medial lip of the linea aspera of femur

Superior pole of patella

Insertion of Quadriceps femoris

Femoral nerve

Innervation of Quadriceps femoris

Quadriceps femoris (Rectus femoris, Vastus lateralis, Vastus intermedius, Vastus medialis)

For extension of leg at knee joint and Stabilizing the patella

Psoas Major (Iliopsoas), Tensor fasciae latae, Pectineus, Sartorius, Rectus femoris

Flexion of the thigh at the hip

Rectus femoris

Which muscle is known as the 'kicking muscle' and is the only quadriceps muscle that spans both the hip and knee?

True

T/f: The Sartorius muscle is the longest muscle in the body and crosses both the hip and knee joints.