lower extremity

Hip Joint Movements

The hip can perform flexion, extension, abduction, adduction, internal rotation, external rotation, and circumduction.

Knee Joint Movements

The knee mainly performs flexion and extension.

Ankle Joint Movements

The ankle can perform dorsiflexion, plantarflexion, inversion, and eversion.

Muscle Action

Muscles pull in the direction that their fibers run.

Direction of Muscle Fibers

The direction of the fibers tells you the direction the muscle will pull.

Thigh Muscle Origins

Muscles that move the thigh usually originate on the pelvic girdle.

Thigh Muscle Insertions

Muscles that move the thigh usually insert on the femur.

Gluteal Muscles Location

The gluteal muscles are located on the back of the hip.

Outer Gluteal Muscles

The main outer gluteal muscles are gluteus maximus, gluteus medius, and gluteus minimus.

Gluteal Muscle Function

Depending on the muscle, they mostly influence hip extension and hip abduction.

Gluteus Maximus Action

The gluteus maximus mainly extends the hip.

Gluteus Medius and Minimus Action

The gluteus medius and gluteus minimus mainly abduct the hip.

Deep Gluteal Muscles Count

There are 6 muscles in the deep gluteal hip stabilizer group.

Deep Gluteal Muscle Example

One important muscle in this group is the piriformis.

Deep Gluteal Lateral Rotators

The 6 muscles are piriformis, superior gemellus, inferior gemellus, obturator internus, obturator externus, and quadratus femoris.

Deep Gluteal Muscle Action

They mainly perform lateral rotation at the hip joint.

Medial Thigh Muscles Location

The medial thigh muscles are located near the groin.

Medial Thigh Muscles Action

They primarily adduct the thigh.

Examples of Medial Thigh Muscles

Examples include adductor longus and adductor magnus.

Injured Muscles in Groin Strain

The medial thigh adductor muscles are usually injured.

Main Hip Flexor Muscles

The main hip flexors are the iliacus and psoas major.

Iliacus and Psoas Major Location

They are primarily found in the abdomen behind the digestive tract.

Crossing Hip Joint

The iliacus and psoas major cross the hip joint anteriorly.

Insertion of Iliacus and Psoas Major

They insert on the femur.

Iliopsoas Formation

They form the iliopsoas.

Leg Movement Muscle Location

Muscles that move the leg at the knee are mostly found on the anterior or posterior side of the thigh.

Anterior Thigh Muscle Group

The quadriceps group is found in the anterior thigh.

Quadriceps Group Action

The quadriceps group extends the knee.

Quadriceps Muscles Origin

Most quadriceps muscles originate on the femur.

Quadriceps Insertion

They insert on the tibia through the patellar ligament.

Quadriceps Muscles List

The 4 quadriceps muscles are rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius.

Hamstring Muscle Location

The hamstring group is mostly found in the posterior thigh.

Hamstring Muscle Actions

The hamstrings mainly flex the knee and extend the hip.

Hamstring Muscles Origin

Most hamstrings originate on the pelvic region.

Hamstring Muscles Insertion

They insert on either the tibia or fibula.

Main Hamstring Muscles

The main hamstring muscles are biceps femoris, semitendinosus, and semimembranosus.

Common Hamstring Injuries

Hamstring injuries are common because the hamstrings tend to be one of the tightest muscle groups in the body.

Knee Flexion Synergists

The sartorius and popliteus muscles assist with knee flexion.

Muscles Moving Foot/Toes Origins

They can originate on the distal femur, tibia, or fibula.

Muscles Moving Foot/Toes Insertions

They can insert on the tarsal bones, metatarsals, or phalanges.

Anterior Leg Muscle Location

The anterior leg muscles are located next to the shin bone.

Ant. Leg Muscle Actions

They are responsible for ankle dorsiflexion or extension of the toes.

Posterior Leg Muscle Location

The posterior leg muscles are located in the calf region.

Post. Leg Muscle Actions

They are largely responsible for ankle plantarflexion or flexion of the toes.

Foot Inversion Muscles

Tibialis anterior and tibialis posterior commonly perform inversion.

Foot Eversion Muscles

Fibularis longus, fibularis brevis, and fibularis tertius commonly perform eversion.

Achilles Tendon Anatomical Name

The anatomical name is the calcaneal tendon.

Calcaneal Tendon Insertion

It inserts on the calcaneus bone.

Calcaneus Definition

The calcaneus is the heel bone.

Number of Tarsal Bones

There are 7 tarsal bones.

Is Calcaneus a Tarsal Bone?

Yes, the calcaneus is one of the 7 tarsal bones.

Femoral Nerve Definition

The femoral nerve is a vital nerve that originates from the lumbar plexus.

Femoral Nerve Supply

The femoral nerve supplies the anterior thigh muscles, especially the quadriceps group.

Patellar Tendon Reflex Test

The patellar tendon reflex test checks the integrity of the femoral nerve.

Leg Movement during Reflex Test

The quadriceps group is stimulated to contract by a motor signal from the femoral nerve, causing the leg to kick forward.

Sciatic Nerve Definition

The sciatic nerve is the most important nerve of the lower limb.

Sciatic Nerve Origin

It originates from the sacral plexus.

Sciatic Nerve Supply Areas

It supplies the posterior thigh, all compartments of the leg, and the entire foot.

Effects of Sciatic Nerve Compression

It can cause muscle weakness and sensory issues in the ipsilateral leg and foot.

Ipsilateral Definition

Ipsilateral means same-sided.