Skeletal System Handouts

Metabolic and bone density disorders

Osteoporosis, osteopenia, Paget’s disease, rickets, osteomalacia

Metabolic and inflammatory joint disorders

osteoarthritis, rheumatoid arthritis, gout, ankylosing spondylitis, bursitis

Genetic and developmental conditions

Osteogenesis imperfecta, Achondroplasia, Fibrodysplasia Ossificans Progressiva, Scoliosis, Kyphosis, Lordosis

Infections, malignancies, and vascular disorders

Osteomyelitis, avascular necrosis, osteosarcoma, osgood-schlatter disease

A condition where bone tissue degrades and mineral density drops, leaving bones brittle and prone to fractures from minimal impact

Osteoporosis

Early stage loss of bone mineral density that is less severe than osteoporosis but elevates fracture risk

Osteopenia

A chronic condition where normal bone remodeling is disrupted, causing new bone to form too quickly and structurally weak, leading to deformities and bone pain

Paget’s Disease of Bone

Softening and weakening of bones caused by severe vitamin d, calcium, or phosphate deficiency

RIckets and osteomalacia

degenerative joint disease caused by gradual brwakdown of articular cartilage, leading to bone on bone friction, pain, and stiffness

osteoarthritis

autoimmune disorder where the immune system attacks the synovium (lining of joints), causing systemic inflammation, pain, and joint deformity

Rheumatoid arthritis

metabolic arthritis caused by high blood levels of uric acid which form sharp urate crystals in joint spaces causing sudden intense pain in big toe

gout

inflammatory arthritis that causes vertebrae in the spine to fuse over tine, reducing spinal flexibility and altering pressure

ankylosing spondylitis

inflammation of fluid filled sacs that cushions bones, tendons, and muscles near joints

bursitis

genetic connective tissue disorder caused by defective collagen production, resulting in fragile bones that break easily

Osteogenesis imperfecta (Brittle bone disease)

genetic bone growth disorder causing dwarfism, characterized by shorter limbs and normal trunk length

Achondroplasia

rare genetic disorder where muscle and connective tissue are gradually replaced by bone, locking joints in place

Fibrodysplasia Ossificans Progressiva (FOP)

Structural spinal curvature deformities affecting alignment

Scoliosis/ Kyphosis/ Lordosis

severe bacterial or fungal infection inside the bone or bone marrow, leading to localized tissue destruction

Osteomyelitis

bone death caused by temporary or permanent loss of blood supply to the tissue, leading to joint collapse (commonly at the hip)

Avascular necrosis

primary malignant bone cancer that originates in the bone forming cells, most often occuring near the ends of long bones

Osteosarcoma

A condition in growing adolescents where repeated stress on the tibial tubercle causes pain and inflammation below the knee.

Osgood-Schlatter Disease

What shape is male pelvis?

Round

What shape is female pelvis?

Triangular

The bony ridge that forms the boundary between the greater (false) pelvis and lesser (true) pelvis that forms the pelvic inlet

Pelvic brim

upper opening of the true (lesser) pelvis, bounded by the pelvic brim.

Pelvic inlet

A large opening in the pelvis formed by the pubis and ischium bones.

Obturator foramen

How does shape of obturator foramen differ in males and females?

Oval in males, triangular in females

The curved structure formed by the left and right pubic bones where they meet below the pubic symphysis.

Pubic arch

General appearance of pelvis in males and females

More massive, rougher, heavier processes in males; less massive, smoother, more delicates processes in females

Pelvic tilt in males and females

Upper ends of pelvis relitavely vertical in males; upper end of pelvis tilted forward in females

Ilium in males and females

Deeper, projects farther above sacroiliac joint in males; shallower, does not project as far above sacroiliac joint in females

Sacrum in males and females

narrower and longer in males, shorter and wider in females

Coccyx in males and females

less movable and more verticale in males, more movable and tilted backwards in females

Width of greater pelvis in males and females

anterior superior spines closer together, hips less flared in males; anterior superior spines farther apart, hips more flared in females

Pelvic inlet in males and females

heart shaped in males; round or oval in females

Pubic symphysis in males and females

Taller in males, shorter in females

Greater sciatic notch in males and females

wider in males and narrower in females

Obturator foramen in males and females

oval in males and triangular in females

Acetabulum in males and females

faces more laterally in males, faces slightly anteriorly in females

Pubic arch in males and females

usually 90 degrees or less in males, usually greater than 100 degrees in females

Forehead; anterior skull

Frontal bone

Large bones forming the top/sides of skull

Parietal bones

Sides of skull around ears

Temporal bones

Back/base of skull

Occipital bone

Central skull bone; forms part of eye sockets and cranial floor

Sphenoid bone

Between the eyes; contributes to nasal cavity and orbit

Ethmoid bone

Upper jaw; holds upper teeth

Maxilla

Lower jaw; movable jaw

Mandible

Cheekbone

Zygomatic bone

Bridge of nose

Nasal bone

Small bone on medial wall of orbit

Lacrimal bone

Forms part of nasal septum

Vomer

Posterior portion of hard palate

Palatine bone

Curved bone inside nasal cavity

Inferior nasal concha

immovable joints between skull bones

Sutures

Between frontal bone + parietal bones

Runs roughly side-to-side across the top of skull

Coronal suture

between the two parietal bones

Sagittal suture

between parietal bones + occipital bone

Lambdoid suture

between temporal + parietal bones

Squamous suture

Projection associated with the temporal bone

Helps form the zygomatic arch

Zygomatic process

Projection of temporal bone behind the ear

Attachment site for muscles

Mastoid process

Thin, pointed projection of temporal bone

Located inferior to the ear

Muscle/ligament attachment

Styloid process

Vertical portion of the mandible

Mandibular ramus

Horizontal portion of mandible

Contains lower teeth

Mandible (body)

Ridges containing the tooth sockets

Alveolar margins

Passage for the optic nerve (CN II) and ophthalmic artery

Optic canal

Opening in the sphenoid

Allows passage of part of the trigeminal nerve (V3)

Foramen ovale

Opening between temporal and occipital bones

Passage for major nerves and the internal jugular vein

Jugular foramen

Passage for the internal carotid artery

Carotid canal

Large opening in the occipital bone

Spinal cord/brainstem connection passes through

Foramen magnum

Opening between parts of the sphenoid

Allows passage of several nerves and vessels serving the orbit

Superior orbital fissure

The hard palate forms the bony roof of the mouth.

It is made primarily of:

Maxilla → palatine process

Palatine bones