02_Terminology, Landmarks and Skeletal System Flashcards
What is the anatomical position?
A person stands erect, palms forward, feet parallel and flat on the floor, arms at the sides of the body.
What does ‘supine’ describe?
The body lying face up.
What does ‘prone’ describe?
The body lying face down.
Define the term ‘medial’.
Nearer to the midline.
Define the term ‘lateral’.
Away from the midline.
What is the definition of ‘bilateral’?
Both sides.
What does ‘unilateral’ mean?
One side.
What does ‘ipsilateral’ refer to?
On the same side.
What is meant by ‘contralateral’?
On the opposite side.
Define ‘proximal’.
Nearer to the trunk.
Define ‘distal’.
Further from the trunk.
What does ‘anterior’ (ventral) mean?
Nearer the front.
What does ‘posterior’ (dorsal) mean?
Nearer the back.
What is the ‘superior’ direction?
Towards the top.
What is the ‘inferior’ direction?
Towards the bottom.
What are the three body planes used in human anatomy?
- Coronal / frontal plane: Separates the body front and back. * Sagittal plane: Separates the body left and right. * Horizontal / transverse plane: Separates the body top and bottom.
How many bones are in the human body?
206 bones.
What percentage of body weight does the skeleton account for?
18%.
List the functions of the skeletal system.
- Supports framework for the body. * Forms boundaries (skull). * Attachment for muscles and tendons. * Permits movement (joints). * Haematopoiesis. * Mineral homeostasis. * Triglyceride storage.
What are osteogenic cells?
Bone stem cells that undergo division to produce osteoblasts.
What is the role of osteoblasts?
Bone-building cells that synthesize and secrete collagen and other components of bony matrix.
What do osteocytes do?
Maintain the daily metabolism of bone, such as nutrient exchange.
What are osteoclasts?
Huge cells that digest bone matrix and are involved in bone resorption.
What type of bone makes up 80% of the skeleton?
Compact bone.
What is an osteon?
The structural unit of compact bone.
What are the four parts of an osteon?
- Haversian canal: Contains blood vessels and nerves. * Lamellae: Concentric rings of calcified matrix. * Canaliculi: Interconnected canals for nutrients/waste. * Lacunae: Small spaces with osteocytes.
What does spongy bone consist of?
An irregular lattice of thin columns called trabeculae.
How does spongy bone differ from compact bone?
Spongy bone does not contain osteons and is lighter due to microscopic spaces.
What is the most abundant mineral in bone?
Calcium phosphate.
What are long bones defined as?
Bones that have a greater length than width.
What are the two main parts of long bones?
- Diaphysis: The shaft. * Epiphyses: The heads.
What separates the epiphysis from the diaphysis?
The epiphyseal plate.
What is the periosteum?
A membrane that surrounds the external surface of bone.
What are the two layers of the periosteum?
- Tough outer fibrous layer. * Inner osteogenic layer.
Name the types of bones.
- Short bones: Carpals, tarsals. * Irregular bones: Vertebrae. * Flat bones: Skull, scapula. * Sesamoid bones: Patella. * Long bones: Femur, tibia.
What are the two ossification pathways?
- Intramembranous ossification. * Endochondral ossification.
What is the epiphyseal growth plate?
A layer of hyaline cartilage in the epiphyses where bone elongation occurs.
Which hormones promote osteoblast activity?
- Growth hormone. * Thyroid hormone. * Oestrogen. * Testosterone. * Calcitonin.
Which hormones promote osteoclast activity?
- Parathyroid hormone. * Cortisol.
What is the role of parathyroid hormone?
Increases blood calcium levels.
What does calcitonin do?
Lowers blood calcium levels.
How does Vitamin D affect calcium absorption?
Facilitates calcium absorption in the intestines.
What factors contribute to decreased Vitamin D levels with age?
- Low sun exposure. * Reduced dietary absorption. * Decreased production of active Vitamin D.
How does mechanical stress affect bone?
Increased mineral deposition and collagen production.
What is the axial skeleton?
The central skeleton containing 80 bones.
What does the axial skeleton protect?
The body’s most vital organs.
What are the components of the skull?
- Cranium. * Face.
What are fontanelles?
Fibrous sutures on a baby’s head that ossify at 12–18 months.
What forms the cranium and face and encapsulates the brain?
The skull.
How are skull bones joined together?
With fibrous joints called sutures.
What are sinuses?
Air-filled cavities in the skull that give resonance to the voice and lighten bones.
What are fontanelles?
Fibrous sutures (soft spots) on a baby’s head that ossify at 12–18 months.
What is the vertebral column composed of?
24 movable vertebrae: 7 cervical, 12 thoracic, 5 lumbar, and fused sacrum and coccyx.
What is the function of the vertebral column?
Protection for spinal cord, movement, support of skull, forms axis of the trunk.
What are intervertebral discs?
Shock-absorbing structures that bind vertebral bodies and separate individual vertebrae.
How many intervertebral discs are present in the spine?
23 discs.
What are the two parts of an intervertebral disc?
Annulus fibrosus and nucleus pulposus.
What is the thoracic cage composed of?
The sternum and 12 pairs of ribs.
What are floating ribs?
Ribs 11 and 12 that have no anterior bony attachments.
How many bones are in the appendicular skeleton?
126 bones.
What are the major areas of the appendicular skeleton?
- Shoulder girdle
- Arm and hand
- Pelvic girdle
- Leg and foot.
What bones make up the shoulder girdle?
- Clavicle
- Scapula
- Humerus
- Ulna
- Radius
- Carpals
- Metacarpals
- Phalanges.
What is the longest and strongest bone in the body?
Femur.
What is the function of skeletal muscles?
To attach to bone and move joints.
What are the three types of joints in the human body?
- Fibrous joints
- Cartilaginous joints
- Synovial joints.
What are synovial joints?
Moveable joints containing fluid that permit the most movement.
What is the function of bursae?
To reduce friction between bone and surrounding tissues.
What is flexion?
A decrease in joint angle.
What is plantar flexion?
Bending the foot down.
What characterizes a fracture?
Any break in a bone.
What is a complete fracture?
Bone broken into two or more fragments.
What occurs during the haematoma stage of fracture repair?
Blood leaks into the fracture site, causing swelling.
What is a sprain?
Trauma that forces a joint beyond its normal range, over-straining ligaments.
What is subluxation?
Incomplete or partial joint dislocation.
What is the main use of X-rays?
To visualize the skeletal system, lungs, heart, and teeth.
What is kyphosis?
An increased thoracic spine curvature.
What is osteoporosis?
Chronic, progressive thinning of the bone leading to increased fracture risk.
What T-Score indicates osteoporosis?
A T-Score lower than -2.5.
List two risk factors for osteoporosis.
- Increasing age
- Female and post-menopausal.
What are the signs and symptoms of osteoporosis?
- Asymptomatic until critical thinness
- Focal pain
- Kyphotic posture
- Loss of height.
What is critical thinness in bones?
Critical thinness whereby fractures occur spontaneously with minor trauma
Commonly affects spine and hips.
What are the symptoms of critical thinness?
Focal pain and kyphotic posture with loss of height
Pain aggravated by prolonged sitting, standing or bending; relieved by lying on side with hips and knees flexed.
What are the allopathic treatments for critical thinness?
- Bisphosphonates (alendronic acid)
- HRT
Bisphosphonates can cause muscle & joint pains, fractures, oesophagitis, and gastritis.
What natural treatments are recommended for critical thinness?
- Healthy alkaline diet
- No caffeine / alcohol
- Calcium, magnesium
- Increase vitamin D3 and K2
- Weight bearing exercise
- Herbs for hormone balancing
- Avoid toxins
What defines osteomalacia and rickets?
Inadequate mineralisation of the bone matrix in spongy and compact bone
Characterised by decalcification and softening of bone.
What is the main cause of osteomalacia and rickets?
Vitamin D deficiency
Possible due to insufficient sunlight, dietary vitamin D, malabsorption disorders, or reduced receptor sites for vitamin D.
What are the signs and symptoms of osteomalacia?
- Deformed bones (bowed legs)
- Possible fractures
- Severe back pain
- Muscle weakness
What is osteomyelitis?
A bacterial infection of the bone marrow resulting in necrosis and bone weakness
osteo- = bone, myelo- = marrow, -itis = inflammation.
What are the symptoms of osteomyelitis?
Severe bone pain, swelling, redness, and warmth
Often worse at night.
What is osteoarthritis?
A degenerative wear-and-tear arthritis of the articular cartilage
Typically affects weight-bearing joints in individuals over 50 years of age.
What are the typical symptoms of osteoarthritis?
- Gradual onset of pain
- Joint pain and stiffness
- Not associated with systemic symptoms
What is the primary cause of osteoarthritis?
Ageing
80% of 65-year-olds have radiological signs of OA.
What are the diagnostic findings of osteoarthritis?
- X-ray revealing joint space narrowing
- Osteophyte (bone spur) formation
- Squaring of rounded joint surfaces
What is rheumatoid arthritis?
Autoimmune inflammation of the synovium potentially affecting all organs except the brain
Affects 1% of people worldwide, more common in women.
What are the key signs and symptoms of rheumatoid arthritis?
- Symmetrical arthritis of small joints
- Progressive morning stiffness (> one hour)
- Deformity of joints
- Fatigue and malaise
What are the allopathic treatments for rheumatoid arthritis?
- Anti-inflammatories
- Immunosuppressants
- Surgery
What are the natural treatments for rheumatoid arthritis?
- Nutrition focusing on anti-inflammatory foods
- Herbs for pain and inflammation
- Homeopathy and acupuncture
What is the difference between osteoarthritis and rheumatoid arthritis?
Osteoarthritis is degenerative wear and tear; rheumatoid arthritis is autoimmune
Affects different tissues and shows different symptoms.
What is ankylosing spondylitis?
A systemic autoimmune disease associated with chronic inflammation of the spine and sacroiliac joints
Often leads to spinal fusion (ankylosis) and stiffness.
What are the signs and symptoms of ankylosing spondylitis?
- Sacroiliac and lower lumbar spine pain
- Worsening morning stiffness
- Lower back symptoms improve with activity
What is gout?
A type of monoarthritis characterised by uric acid crystal deposition in synovial joints
Common in men over 40 years of age.
What are the causes of gout?
- Increased intake of purine-rich foods
- Dehydration
- Kidney disease
- Medications
- Obesity
- Excessive alcohol consumption
What are the symptoms of gout?
- Intense pain in joints
- Red, hot, swollen joints
- Sudden onset of symptoms
- Shiny skin over the joint
What is disc herniation?
The nucleus pulposus of the intervertebral disc leaks out through the annulus fibrosus
Commonly affects lumbar and cervical spine.
What is bursitis?
Inflammation of a bursa
Commonly affects the shoulder and hip.
What are the common causes of bursitis?
- Repetitive use
- Sudden trauma
- Infection
- Wear and tear
