Exam three 1

Hip and Pelvis Muscles

• Gluteus Maximus Origin: Posterior iliac crest, sacrum, coccyx
• Gluteus Maximus Insertion: Gluteal tuberosity of femur, IT band
• Gluteus Maximus actions include hip extension and external rotation
• Upper fibers of the gluteus maximus cause abduction
• Lower fibers of the gluteus maximus cause adduction
• Gluteus Medius Origin: Outer surface of the ilium
• Gluteus Medius Insertion: Lateral surface of greater trochanter
• Gluteus Medius action is hip abduction
• Anterior fibers of the gluteus medius cause internal rotation
• Posterior fibers of the gluteus medius cause external rotation
• Piriformis Origin: Anterior surface of sacrum
• Piriformis Insertion: Greater trochanter of femur
• Piriformis Actions: External rotation of extended hip, abduction of flexed hip
• Psoas Major and Minor Origin: T12-L5 vertebral bodies and transverse processes (Major); T12 & L1 vertebrae (Minor)
• Psoas Major and Minor Insertion: Lesser trochanter of femur (Major); pectineal line (Minor)
• Psoas Major and Minor Actions: Hip flexion, trunk flexion when femur is fixed

Knee and Thigh Muscles

• Rectus Femoris Origin: Anterior inferior iliac spine (AIIS)
• Rectus Femoris Insertion: Tibial tuberosity via patellar tendon
• Rectus Femoris Actions: Knee extension, hip flexion
• Vastus Medialis Origin: Linea aspera (medial lip)
• Vastus Medialis Insertion: Tibial tuberosity via patellar tendon
• Vastus Medialis Action: Knee extension
• Vastus Intermedius Origin: Anterior and lateral surface of femur
• Vastus Intermedius Insertion: Tibial tuberosity via patellar tendon
• Vastus Intermedius Action: Knee extension
• Sartorius Origin: Anterior superior iliac spine (ASIS)
• Sartorius Insertion: Medial tibia (pes anserinus)
• Sartorius Actions: Hip flexion, abduction, external rotation; knee flexion
• Gracilis Origin: Inferior pubic ramus
• Gracilis Insertion: Medial surface of tibia (pes anserinus)
• Gracilis Actions: Hip adduction, knee flexion, internal rotation of knee
• Semimembranosus Origin: Ischial tuberosity
• Semimembranosus Insertion: Posterior medial tibial condyle
• Semimembranosus Actions: Hip extension, knee flexion, internal rotation of knee
• Biceps Femoris Origin (Long head): Ischial tuberosity
• Biceps Femoris Origin (Short head): Linea aspera
• Biceps Femoris Insertion: Head of fibula
• Biceps Femoris Actions: Knee flexion, external rotation; hip extension (long head)

Hip and Pelvis Movements

• Common 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), and rotation (internal/external rotation)
• Pelvic rotations are movements of the pelvis, not the hip joint itself, but do influence hip movement and alignment

Ankle and Foot Muscles

• Gastrocnemius Origin: Posterior surfaces of medial and lateral femoral condyles
• Gastrocnemius Insertion: Posterior surface of calcaneus via Achilles tendon
• Gastrocnemius Actions: Plantar flexion of the ankle, assists with knee flexion
• Soleus Origin: Posterior surface of proximal tibia and fibula
• Soleus Insertion: Posterior calcaneus via Achilles tendon
• Soleus Action: Plantar flexion of the ankle
• Tibialis Anterior Origin: Lateral condyle and upper lateral surface of tibia
• Tibialis Anterior Insertion: Medial cuneiform and base of first metatarsal
• Tibialis Anterior Actions: Dorsiflexion and inversion of foot

Foot and Ankle Injuries

• The most commonly injured ligaments during ankle sprains caused by excessive inversion include:
• Anterior talofibular ligament (ATFL)
• Calcaneofibular ligament (CFL)

Trunk and Spine Muscles and Actions

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

Trunk and Spine Information

• The 5 segments of the spinal column and the number of vertebrae in each include:
• Cervical – 7
• Thoracic – 12
• Lumbar – 5
• Sacral - 5 (fused)
• Coccygeal – 4 (fused)
• The vertebral body is the load-bearing part of the vertebrae
• The processes that come off the sides and back of the vertebrae are called transverse processes (sides) and spinous process (back)
• These processes 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
• The 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 absorb shock, allow spinal flexibility, and distribute loads during movement
• Intervertebral discs are composed of the annulus fibrosus (outer ring) and nucleus pulposus (gel-like center)
• In 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