Lecture 2 - Skeletal System Flashcards
1
Q
Supine
Prone
A
Supine - facing up
Prone - facing down
2
Q
Ipsilateral
A
On the same side
3
Q
Contralateral
A
On the opposite side
4
Q
Proximal
A
Nearer the trunk
5
Q
Distal
A
Further from the trunk
6
Q
Anterior (ventral)
A
Nearer the front
7
Q
Posterior (dorsal)
A
Nearer the back
8
Q
Superior
A
Towards the top
9
Q
Inferior
A
Towards the bottom
10
Q
Coronal/frontal plane
A
Separating the body front and back
11
Q
Sagittal plane
A
Separating the body left and right
12
Q
Horizontal / transverse plane
A
Separating the body top and bottom
13
Q
Human skeleton - FUNCTIONS
A
- Supports framework
- Boundaries (skull)
- Attachment (for muscles and tendons)
- Movement
- Haematopoiesis (red blood cell formation in red bone marrow)
14
Q
Types of bone cells
A
- Osteogenic cells
- Osteoblasts
- Osteocytes
- Osteoclasts
15
Q
Osteogenic cells
A
Bone stem cells
Undergo divisioin
16
Q
Osteoblasts
A
- Bone-building cells
- Synthesis and secrete collagen
17
Q
Osteocytes
A
- Mature bone cells
- Maintain daily metabolism, exchange of nutrients
18
Q
Osteoclasts
A
- ‘Ruffled border’ - digest bone matrix
- ‘Resorption’ - breakdown of bone matrix
19
Q
2 types of bone
A
Compact
Spongy
20
Q
Compact bone
A
80% of skeleton is compact bone
Structural unit of bone - osteon
21
Q
Osteon - 4 parts
A
- Haversian canal - blood vessels and nerves
- Lamellae - concentric rings of calcified extracellular matrix (minerals and collagen)
- Canaliculi - interconnected canals - route for nutrients / waste
- Lacunae - small spaces with osteocytes
22
Q
Spongy bone
A
- No osteons
- Irregular lattice of thin columns - trabeculae
- Lighter
- Filled with bone marrow
- Contain blood vessels to nourish the bone
- Covered with compact bone
23
Q
Periosteum
A
- Double-layer membrane
- Tough outer fibrous layer - protection
- Inner osteogenic layer - osteoblasts and osteoclasts - growth and repair
24
Q
5 types of bones and location
A
- Short - carpals (wrist), tarsals (feet)
- Irregular - vertebrae
- Flat - skull, scapula, pelvis
- Sesamoid - patella
- Long - femur, tibia
25
Calcitonin
* **Hormone** that lowers blood calcium levels
* Secreted by **thyroid** gland
* **Increases bone formation** by - inhibiting osteoclasts and promoting osteoblasts (which deposit calcium in bones)
26
What is the effect of Vitamin D on bones?
* Facilitates calcium absorption in intestines
* Directly involved in bone turnover
* Vit D3 works with Vit K2
* Vit D decreases with age and high alcohol intake
27
What is the effect of exercise on bones?
Mechanical stress ⇢ increased mineral deposition and collagen production
28
Axial skeleton
* ‘Central’ skeleton
* 80 bones
* Protect vital organs
* Skull, thoracic cage, spine
29
Vertebral column
24 vertebrae
* Cervical (7) C1 - C7
* Thoracic (12) T1 - T12
* Lumbar (5) L1 - L5
* Sacrum and coccyx (fused bones)
Functions:
* Protects spinal cord
* Movement
* Support of skull
30
Thoracic Cage and Ribs
Sternum
12 ribs
Ribs 11 and 12 are 'floating ribs)
31
Appendicular Skeleton
* Distal skeleton
* 126 bones
* Functions - movement and organ protection
* Shoulder girdle, arm and hand
* Pelvic girdle, leg and foot
32
Arms and Shoulder
* Clavicle (anterior)
* Scapula (posterior)
* Humerus (upper arm)
* Ulna (medial forearm)
* Radius (lateral forearm)
* Carpals (wrist bones)
* Metacarpals (bones in between carpals and digits)
* Phalanges (fingers)
33
Pelvic Girdle is made up of:
* Hip bones
* Sacrum
* Coccyx
Protects reproductive organs and bladder
34
Leg
* Femur (longest and strongest bone in body)
* Tibia (shin bone)
* Fibula (lateral lower leg)
* Patella (sesamoid bone)
* Tarsals (ankle bones)
* Metatarsals (connecting middle section of foot)
* Phalanges (toes)
35
Skeletal Muscles
* Muscles that attach to bone (via **tendons**) and move joints
36
3 types of joints
1. **Fibrous** - bones held tightly together, little movement - skull
2. **Cartilaginous** - articulating bones connected by cartilage, little or no movement - epiphyseal growth plate, intervertebral discs
3. **Synovial** - permit the most movement
1. Covered by a layer of **hyaline** cartilage (reduces friction, shock absorber)
2. **Synovial fluid** - provide nutrients
3. Examples - ball & socket, shoulder and hip
37
Bursae
* Closed fluid-filled sacs
* Reduce friction
* Between skin and bone, tendon and bone
* Knee
38
Angular Movements
1. **Flexion** - decrease in joint angle
2. **Extension** - increase in joint angle
3. **Rotation** - movement around its longitudinal axis
4. **Lateral flexion** - movement of trunk away from middle (side bending)
5. **Abduction** - movement away from midline
6. **Adduction** - movement toward midline
7. **Circumduction** - circular movement
39
Special Movements
1. Elevation - superior movement (up)
2. Depression - inferior movement (down)
3. Protraction - anterior movement (forward)
4. Retraction - posterior movement (backward)
5. Inversion - medial movement of sole (turn in)
6. Eversion - lateral movement of sole (turn out)
7. Dorsiflexion - bending foot up
8. Plantar flexion - bending foot down
9. Supination - movement of forearm to turn palm up
10. Pronation - movement of forearm to turn palm posteriorly
11. Opposition - movement of thumb across palm to touch fingertips
40
Bone Fracture Repair
1. **Haematoma** (and **inflammation**) - blood vessels break, blood flows in
2. **Fibrocartilaginous callus formation** - _phagocytes_ clean up debris, fibroblasts lay down _collagen_ to form _soft callus_
3. **Bony callus formation** - _osteoblasts_ replace callus with new bone
4. **Bone remodelling** - callus is mineralised and _compact bone_ laid down
41
Healthy (and unhealthy) spine curvature
Kyphosis
Hyper-kyphosis
42
Lordosis
Increased spinal concavity
43
Scoliosis
Lateral ‘S’ shaped curve in the spine
44
Osteoporosis
* Chronic, progressive thinning of bone
* Caused by decreased bone mineral density ⇢ bone fragility ⇡ fracture
* * Risk factors
* Age
* Female & post-menopausal
* Poor diet (acid - high sugar and protein), low in minerals, caffeine, fizzy drinks
* Drugs - long-term corticosteroid therapy (› 6 months)
* GI diseases - liver disease, malabsorption syndromes, low stomach acidity
* Genetics
* Sedentary lifestyle
* Low body weight
* High alcohol consumption and smoking
* Toxins (heavy metals)
45
Osteomalacia and Rickets
* Inadequate mineralisation of bone matrix
* Rickets - prior to epiphyseal plate closure (\<18 years)
* Osteomalacia - adolescent or adult
* Cause - Vit D deficiency
46
Osteomyelitis
* Bacterial infection of the bone marrow
* Necrosis and bone weakness
* Causes - bacterial infection through blood supply or post fracture
* Causes - Immunosuppression, diabetes, IV drug users
47
Ankylosing Spondylitis
* Autoimmune
* Chromic inflammation of the spine and sacroiliac joints
* Often leads to spinal fusion ('ankylosis') and stiffness
* Onset 15-30 years, mostly males
* Genetic association HLA-B27
* Links with inflammatory bowel disease, leaky gut
* Lower lumbar spine pain, progressing up the spine
* Lower back symptoms improve with activity
* Patients often become kyphotic
* Hip and heel (achilles) pain common
* Systemic symptoms - fever, malaise, fatigue
* Diagnosis - inflammatory markers (ESR/CRP), HLA-B27 positive
* X-ray/MRI - bamboo spine
