exam three 3

Hip and Pelvis Muscles

• Gluteus Maximus
• Originates from the posterior iliac crest, sacrum, and coccyx.
• Inserts on the gluteal tuberosity of the femur and the IT band.
• Responsible for hip extension and external rotation.
  • Upper fibers facilitate abduction.
  • Lower fibers facilitate adduction.
• Gluteus Medius
• Originates from the outer surface of the ilium.
• Inserts on the lateral surface of the greater trochanter.
• Responsible for hip abduction.
  • Anterior fibers facilitate internal rotation.
  • Posterior fibers facilitate external rotation.
• Piriformis
• Originates from the anterior surface of the sacrum.
• Inserts on the greater trochanter of the femur.
• Causes external rotation of an extended hip and abduction of a flexed hip.
• Psoas Major and Minor
• Originates from the T12-L5 vertebral bodies and transverse processes (Major) and the T12 & L1 vertebrae (Minor).
• Inserts on the lesser trochanter of the femur (Major) and the pectineal line (Minor).
• Causes hip flexion and trunk flexion (when the femur is fixed).

Knee and Thigh Muscles

• Rectus Femoris
• Originates from the anterior inferior iliac spine (AIIS).
• Inserts on the tibial tuberosity via the patellar tendon.
• Responsible for knee extension and hip flexion.
• Vastus Medialis
• Originates from the linea aspera (medial lip).
• Inserts on the tibial tuberosity via the patellar tendon.
• Responsible for knee extension.
• Vastus Intermedius
• Originates from the anterior and lateral surface of the femur.
• Inserts on the tibial tuberosity via the patellar tendon.
• Responsible for knee extension.
• Sartorius
• Originates from the anterior superior iliac spine (ASIS).
• Inserts on the medial tibia (pes anserinus).
• Facilitates hip flexion, abduction, and external rotation, and knee flexion.
• Gracilis
• Originates from the inferior pubic ramus.
• Inserts on the medial surface of the tibia (pes anserinus).
• Facilitates hip adduction, knee flexion, and internal rotation of the knee.
• Semimembranosus
• Originates from the ischial tuberosity.
• Inserts on the posterior medial tibial condyle.
• Facilitates hip extension, knee flexion, and internal rotation of the knee.
• Biceps Femoris
• Originates from the ischial tuberosity (long head) and linea aspera (short head).
• Inserts on the head of the fibula.
• Facilitates knee flexion, external rotation, and hip extension (long head).

Hip and Pelvis

• Hip joint movements include flexion, extension, abduction, adduction, internal rotation, and external rotation.
• Pelvic tilt/rotation includes:
• Anterior tilt (hip flexion).
• Posterior tilt (hip extension).
• Lateral tilt (hip abduction/adduction).
• Rotation (internal/external rotation).
• Pelvic rotations are movements of the pelvis, not the hip joint.
• These influence hip movement and alignment.

Ankle and Foot

• Gastrocnemius
• Originates from the posterior surfaces of the medial and lateral femoral condyles.
• Inserts on the posterior surface of the calcaneus via the Achilles tendon.
• Facilitates plantar flexion of the ankle and assists with knee flexion.
• Soleus
• Originates from the posterior surface of the proximal tibia and fibula.
• Inserts on the posterior calcaneus via the Achilles tendon.
• Facilitates plantar flexion of the ankle.
• Tibialis Anterior
• Originates from the lateral condyle and upper lateral surface of the tibia.
• Inserts on the medial cuneiform and base of the first metatarsal.
• Facilitates dorsiflexion and inversion of the foot.
• Injured ligaments during ankle sprains caused by excessive inversion include:
• Anterior talofibular ligament (ATFL)
• Calcaneofibular ligament (CFL)

Trunk and Spine

• Rectus Abdominis: Trunk flexion, posterior pelvic tilt.
• External Oblique: Trunk flexion, lateral flexion (same side), rotation (opposite side).
• Internal Oblique: Trunk flexion, lateral flexion (same side), rotation (same side).
• Transverse Abdominis: Compresses abdominal cavity, stabilizes lumbar spine.
• Erector Spinae (Iliocostalis, Longissimus, Spinalis): Trunk extension, lateral flexion.
• Quadratus Lumborum: Lateral flexion of the trunk, lumbar extension, pelvic elevation.

Spinal Column Segments

• The spinal column consist of 5 segments with the following number of vertebrae:
• Cervical - 7
• Thoracic - 12
• Lumbar - 5
• Sacral - 5 (fused)
• Coccygeal - 4 (fused)

Vertebrae Features

• The vertebral body is the load-bearing part of the vertebrae.
• Transverse processes (sides) and spinous process (back): These serve as attachment sites for muscles and ligaments, increasing leverage for movement and stability.
• Facet joints are small joints between vertebrae that guide and restrict movement, particularly resisting excessive rotation and shear forces.
• A spine should have four curves in normal vertical alignment: cervical lordosis, thoracic kyphosis, lumbar lordosis, and sacral kyphosis.
• Lordosis: Excessive inward curve (lumbar or cervical)
• Kyphosis: Excessive outward curve (thoracic)
• Scoliosis: Abnormal lateral curve of the spine

Intervertebral Discs

• Intervertebral discs absorb shock, allow spinal flexibility, and distribute loads during movement.
• Discs composed of the annulus fibrosus (outer ring) and nucleus pulposus (gel-like center)
• Disc herniation: The nucleus pulposus pushes through a tear in the annulus fibrosus, possibly pressing on nerves
• Compression is the most common form of loading on the discs.