Bone Structures and Functions

Supraorbital foramen (Frontal)

Allows the supraorbital nerve and blood vessels to pass to the forehead and upper eyelid

Superior and inferior temporal lines (Parietal)

Provide attachment points for the temporalis muscle and its fascia, which assist in chewing

Zygomatic process (Temporal)

Forms part of the cheekbone arch and provides attachment for the masseter muscle

Mandibular fossa (Temporal)

Receives the mandibular condyle to form the TMJ joint

Mastoid process (Temporal)

Provides attachment for neck muscles that move and stabilize the head

External & Internal acoustic meatus (Temporal)

EAM: conducts sound waves toward the eardrum; IAM: allows cranial nerve 7, 8, and blood vessels to pass

Styloid process (Temporal)

Provides attachment for muscles and ligaments involved in swallowing and tongue movement

Carotid canal (Temporal)

Allows the internal carotid artery and sympathetic nerve plexus to enter the skull

Jugular foramen (Temporal)

Allows the internal jugular vein to begin and cranial nerves 9, 10, and 11 to pass through

Occipital Condyle (Occipital)

Articulate with the atlas (C1) to allow nodding of the head

Foramen magnum (Occipital)

Large opening allowing the spinal cord to connect with the brain stem

Hypoglossal canal (Occipital)

Allows the hypoglossal nerve (CN 12), which controls tongue movements, to pass

Sella turcica (Sphenoid)

Houses and protects the pituitary gland

Optic canal (Sphenoid)

Allows the optic nerve (CN 2) and ophthalmic artery to pass into the orbit

Foramen ovale (Sphenoid)

Allows the mandibular division of cranial nerve 3 and other structures to pass through the skull

Crista galli (Ethmoid)

Provides attachment for the falx cerebi, a membrane that separates the brain's cerebral hemispheres

Cribriform plates (Ethmoid)

Contain tiny openings that allow olfactory nerve fibers to pass from the nasal cavity to the brain

Perpendicular plate (Ethmoid)

Forms superior portion of the nasal septum, separating the nasal cavity into 2 sides

Middle nasal concha (Ethmoid)

Helps warm, humidify, and filter inhaled air by creating airflow turbulence

Superior nasal concha (Ethmoid)

Helps direct airflow and improve air conditioning and odor detection in the nasal cavity

Temporal process (Zygomatic)

Extends backward to join the zygomatic process of the temporal bone, forming the zygomatic arch

Alveolar process (Maxilla)

Holds the sockets for the upper teeth

Palatine process (Maxilla)

Forms anterior portion of the hard palate, separating the oral and nasal cavities

Incisive foramen / canal (Maxilla)

Allows the nasopalatine nerve and associated blood vessels to pass through the anterior hard palate

Infraorbital foramen (Maxilla)

Allows the infraorbital nerve and blood vessels to reach the skin of the cheek and upper lip

Horizontal plate (Palatine)

Forms the posterior portion of the hard palate

Vertical plate (Palatine)

Forms part of the lateral wall of the nasal cavity and contributes to the orbit and pterygopalatine region

Nasolacrimal duct and canal (Lacrimal)

Provides a passage for tears to drain from the eye into the nasal cavity

Nasal bone

Forms the bridge of the nose and supports the upper part of the nasal structure

Body (Mandible)

Forms the horizontal portion of the lower jaw and holds the lower teeth

Ramus (Mandible)

Forms the upright portion of the mandible and provides attachment for chewing muscles

Mandibular condyle (Mandible)

Articulates with the temporal bone to form the TMJ, allowing jaw movement

Coronoid process (Mandible)

Provides attachment for the temporalis muscles, which elevates the jaw during chewing

Mental foramen (Mandible)

Allows the mental nerve and blood vessels to pass to the chin and lower lip

Vertical plate (Vomer)

Forms the inferior and posterior portion of the nasal septum, separating the nasal cavity into 2 sides

Hyoid body, greater & lesser horns

Anchors the tongue and muscles of the neck, supporting swallowing and speech; does not articulate with another bone

Body (Vertebrae)

Supports most of the weight placed on the vertebral column

Vertebral foramen (Vertebrae)

Creates an opening for the spinal cord; foramina together form the vertebral canal

Vertebral arch (Vertebrae)

Forms the posterior portion of the vertebral foramen and protects the spinal cord

Pedicle (Vertebrae)

Connects the vertebral body to the vertebral arch and forms part of the vertebral notch

Lamina (Vertebrae)

Forms the posterior part of the vertebral arch and helps protect the spinal cord

Transverse process (Vertebrae)

Provides attachment for muscles and ligaments; thoracic vertebrae also articulate with ribs here

Spinous process (Vertebrae)

Provides attachment for back muscles and ligaments

Intervertebral foramen / notch (Vertebrae)

Allows spinal nerves and blood vessels to pass out of the vertebral canal

Superior & inferior articular facet / process (Vertebrae)

Articulate with neighboring vertebrae to guide movement and stabilize the spine

Annulus fibrosus (Intervertebral disks)

Tough outer ring that holds the disk together, resists twisting, and contains nucleus pulposus

Nucleus pulposus (Intervertebral disks)

Soft, gel-like center that distributes pressure and absorbs shock between vertebrae

Atlas superior articular facets

Articulate with the occipital condyles to support the skull and allow the head to nod up and down

Axis odontoid process (dens)

Acts as a pivot around which the atlas and head rotate from side to side

Auricular surface (Sacrum)

Articulates with the ilium to form the sacroiliac joint, transferring body weight to the pelvis

Medial sacral crest (Sacrum)

Provides attachment for muscles and ligaments that stabilize sacrum and pelvis

Sacral foramina (Sacrum)

Allow sacral spinal nerves and blood vessels to pass through the sacrum

Coccyx

Tailbone; 3-5 fused vertebrae; provides attachment for pelvic floor muscles and ligaments

Head (Ribs)

Articulates with the bodies of thoracic vertebrae

Neck (Ribs)

Connects the head of the rib to the tubercle

Tubercle (Ribs)

Articulates with the transverse process of a thoracic vertebra

Manubrium (Sternum)

Upper part of the sternum; articulates with clavicles and first ribs

Body (Sternum)

Largest part of the sternum; provides attachment for costal cartilages

Xiphoid process (Sternum)

Inferior tip of the sternum; provides attachment for diaphragm and abdominal muscles

Jugular notch (Sternum)

Central notch at top of manubrium; serves as a palpable anatomical landmark

Clavicle (Sternal and acromial ends)

Connects upper limb to axial skeleton and acts as a brace

Acromial process (Scapula)

Articulates with clavicle and provides attachment for shoulder muscles

Scapular spine (Scapula)

Divides posterior scapula into two fossae and provides attachment for shoulder muscles

Supraspinous fossa (Scapula)

Houses supraspinatus muscle to help initiate arm abduction

Infraspinous fossa (Scapula)

Houses infraspinatus muscle, which externally rotates the arm

Subscapular fossa (Scapula)

Houses subscapularis muscle, which internally rotates the arm

Coracoid process (Scapula)

Provides attachment for muscles and ligaments that stabilize and move the shoulder

Glenoid cavity (Scapula)

Receives head of the humerus to form the shoulder joint

Anatomical neck (Humerus)

Marks boundary between head and proximal shaft; provides attachment for joint capsule

Surgical neck (Humerus)

Narrow region below tubercles; common site for fractures

Greater tubercle (Humerus)

Provides attachment for three rotator cuff muscles

Lesser tubercle (Humerus)

Provides attachment for the subscapularis muscle

Intertubercular groove (Humerus)

Guides and holds tendon of long head of biceps brachii

Deltoid tuberosity (Humerus)

Provides attachment for the deltoid muscle

Capitulum (Humerus)

Articulates with head of the radius to allow elbow movement

Trochlea (Humerus)

Articulates with trochlear notch of ulna to form main hinge of elbow

Medial epicondyle (Humerus)

Provides attachment for many forearm flexor muscles

Lateral epicondyle (Humerus)

Provides attachment for many forearm extensor muscles

Coronoid fossa (Humerus)

Receives coronoid process of ulna during elbow flexion

Olecranon fossa (Humerus)

Receives olecranon process of ulna during elbow extension

Trochlear notch (Ulna)

Articulates with trochlea of humerus to form elbow hinge joint

Coronoid process (Ulna)

Helps stabilize elbow and fits into coronoid fossa during flexion

Olecranon process (Ulna)

Forms bony point of elbow and receives triceps tendon

Radial notch (Ulna)

Articulates with head of radius, allowing pronation and supination

Head (Ulna)

Distal end of ulna; articulates with radius near wrist

Styloid process (Ulna)

Provides attachment for ligaments that stabilize the wrist

Head (Radius)

Articulates with capitulum of humerus and radial notch of ulna

Radial tuberosity (Radius)

Provides attachment for biceps brachii tendon

Styloid process (Radius)

Provides attachment for wrist ligaments and stabilizes wrist joint

Carpals

Help connect proximal and distal rows and contribute to wrist movement and stability

Metacarpals

Form framework of palm and support hand movements and grip

Phalanges (Hand)

Form fingers and allow grasping and fine motor movements

Iliac crest (Ilium)

Provides attachment for abdominal, back, and hip muscles; serves as palpable landmark

ASIS, PSIS, AIIS, PIIS

Provide attachment points for muscles and ligaments of hip and thigh

Greater sciatic notch (Ilium)

Helps form greater sciatic foramen, allowing sciatic nerve to pass

Auricular surface (Ilium)

Articulates with auricular surface of sacrum to form sacroiliac joint

Iliac fossa (Ilium)

Provides attachment for iliacus muscle, which flexes the hip

Ischial tuberosity (Ischium)

Supports body weight when sitting and provides attachment for hamstring muscles

Ischial spine (Ischium)

Provides attachment for pelvic ligaments and serves as landmark

Pubic symphysis (Pubis)

Cartilaginous joint joining left and right pubic bones for pelvic stability