Skeletal System Vocabulary - Spine, Thorax, Pelvis, and Limbs

Vocabulary flashcards covering the spine, thorax, pelvis, and limbs based on the lecture notes.

Vertebral column

A flexible column from the base of the skull to the lower back that houses the spinal cord and protects it; composed of vertebrae connected by discs and ligaments.

Newborn vertebrae count

33 vertebrae: 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, 4 coccygeal.

Adult vertebrae count

26 vertebrae after fusion of the sacral and coccygeal sections.

Cervical vertebrae count

7 vertebrae labeled C1–C7.

Thoracic vertebrae count

12 vertebrae labeled T1–T12.

Lumbar vertebrae count

5 vertebrae labeled L1–L5.

Sacrum and coccyx fusion

In adults, sacral and coccygeal vertebrae are fused into single bones (sacrum and coccyx).

Four natural curvatures of the spine

The cervical, thoracic, lumbar, and sacral curves increase strength, balance, absorb shocks, and protect the vertebrae.

Lordosis

Excessive curvature of the lumbar (abdominal) region of the spine.

Kyphosis

Excessive curvature of the thoracic spine, commonly seen in the elderly.

Scoliosis

Bending of the spine sideways; a pathology often seen in teenagers and sometimes hereditary.

Intervertebral discs

Discs between adjacent vertebrae composed of an outer annulus fibrosus and a inner nucleus pulposus that absorb shocks.

Nucleus pulposus

Gel-like inner portion of an intervertebral disc that absorbs shocks.

Annulus fibrosus

Fibrous outer ring of an intervertebral disc.

Herniated disc

Protrusion of the nucleus pulposus through the annulus fibrosus causing nerve pressure and pain.

Atlas (C1)

The first cervical vertebra; ring-shaped and lacking a vertebral body; articulates with the occipital bone.

Axis (C2)

The second cervical vertebra; has a dens (odontoid process) that forms a joint with the Atlas.

Dens (odontoid process)

Peg-like projection from the axis that articulates with the atlas to form a pivot for head rotation.

Foramen transversarium

Transverse foramina in cervical vertebrae through which the vertebral arteries and veins pass.

Occipital condyles

Articulate with the atlas at the base of the skull.

Atlanto-occipital joint

Joint between the atlas and the occipital bone that allows nodding (yes) of the head.

Atlanto-axial joint

Joint between the atlas and axis that enables head rotation (no).

Cervical vertebrae features

Small vertebral bodies and large vertebral foramina; transverse foramina present; support head and allow skull movement.

Thoracic vertebrae features

Twelve vertebrae with facets for rib articulation; longer spinous processes.

Lumbar vertebrae features

Five vertebrae with large, thick bodies; short and thick processes; bear most body weight.

Sacrum

Triangular bone formed by fusion of S1–S5; articulates with L5, coccyx, and pelvic bones; contains the sacral canal and hiatus.

Sacral canal and hiatus

Passages through which nerves pass inside the sacrum; the hiatus is the lower opening of the canal.

Coccyx

Small triangular tailbone formed by fusion of coccygeal vertebrae.

Vertebral foramen

Hole in each vertebra through which the spinal cord passes.

Intervertebral discs

Cartilaginous cushions between vertebrae; composed of annulus fibrosus and nucleus pulposus.

Acetabulum

Hip socket; rounded part of the pelvis that articulates with the head of the femur.

Obturator foramen

Large opening in the hip bone for vessels and nerves to pass.

Pelvic girdle

Hip girdle formed by fused ilium, ischium, and pubis; supports the upper body and connects to the spine.

Sacroiliac joint

Joint between the sacrum and the ilium with limited mobility.

Male vs female pelvis differences

Female pelvis is wider and shallower with a pubic angle > 90 degrees; obturator foramen is oval in females and round in males; adapted for childbirth.

Hip fracture (neck of femur)

Fracture of the femoral neck, often surgically repaired with screws.

Femur

The thigh bone; the longest bone in the body; head forms the hip joint; greater and lesser trochanters near the neck.

Knee joints and patella

Patella (kneecap) is a sesamoid bone that stabilizes the knee and moves within the tendon.

Tibia and fibula

The tibia is the larger front shin bone; the fibula is the slender lateral bone; they articulate with each other and with the talus.

Medial malleolus

Medial ankle projection on the tibia.

Lateral malleolus

Lateral ankle projection on the fibula.

Head of radius

Rounded proximal end of the radius that forms a joint with the humerus.

Olecranon process

Posterior projection of the ulna that forms the elbow prominence.

Ulna and radius features

Radius has a head and tuberosity; ulna has an olecranon and coronoid processes; both have distal/styloid features.

Carpal bones (wrist)

Eight short bones forming the wrist: Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, Hamate.

Metacarpals

Five hand bones linking carpal bones to the phalanges.

Phalanges

Bones of the fingers; each finger has proximal, middle, and distal phalanges (thumb lacks a middle phalanx).

Humerus features

Proximal head forms the shoulder joint; anatomical neck; greater and lesser tubercles; distal capitulum and trochlea; olecranon fossa; epicondyles.

Rib cage (thorax)

Bony framework consisting of sternum, costal cartilages, ribs, and thoracic vertebrae.

Ribs types

True ribs (1–7) attach to the sternum; false ribs (8–12) attach to the rib above; floating ribs (11–12) do not attach to the sternum.

Sternum parts

Manubrium, body, and xiphoid process; fused by about age 25.

Sternal cartilages and joints

Costal cartilages connect true ribs to the sternum; sternocostal joints form between ribs and sternum.

Foot bones overview

Three groups: tarsals (ankle), metatarsals (foot), and phalanges (toes).

Tarsal bones

Seven bones including calcaneus (heel) and talus that form the ankle joint.

Calcaneus

The heel bone; largest and strongest tarsal; bears weight.

Arches of the foot

Two arches: longitudinal and transverse; arches act as shock absorbers and provide flexibility.

Carpals mnemonic (wrist bones)

Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, Hamate.

Arch support and flat feet

Flat arch refers to decreased height of the arches, can result from weight, heels, or genetics.