(PM3B) Musculoskeletal Therapeutics Flashcards
What comprises the musculoskeletal system? 6
(1) Bones
(2) Joints
(3) Muscles
(4) Tendons
(5) Ligaments
(6) Cartilage
What are tendons?
Attaches muscle to bone
What are ligaments?
Attach bone to bone
What is the most common musculoskeletal condition?
Osteoarthritis
What is the first line management of lower back pain?
(1) stretching/ strengthening/ aerobics/ yoga
then 2nd line
(2) NSAIDs
then 3rd line
(3) Weak opioids, e.g. codeine
When may surgery be required for lower back pain?
Prolapsed discs
What happens to bones with ageing?
Loss of bone mass in those >30yrs old
Bone loss accelerates post-menopause in women (due to drop in oestrogen levels)
What happens to joints with ageing?
Stiffen with age
Ligaments + tendons become more rigid
Cartilage thins, leading to increased friction
- arthritis
What happens to muscle with ageing?
Progressively lost from ~30yrs old
- sarcopenia
Reduced mass + strength leads to an increase in risk of injury
What is the main symptom of most musculoskeletal conditions?
Pain
What is bone pain?
Deep/ penetrating pain
What is muscle pain?
Often less intense than bone pain
What is joint, ligament, or tendon pain?
Stiff
Dull ache
Less intense than bone pain
Worse when moved/ stretched
When can back pain be misleading?
Kidney infection/ stone
How are musculoskeletal conditions diagnosed?
Observation of gait/ movement of the patient
Questions
Physical examination
Blood tests
- biomarkers
- inflammatory markers
- CT scan
- X-ray
What are some of the functions of bone?
(1) Support
- framework for attachment of muscles
(2) Protection
- of internal organs
(3) Movement
- levers + points of attachment for muscles
(4) Mineral storage
- reservoir for calcium
(5) Haematopoiesis
- housing of bone marrow
- production of blood cells + platelets
(6) Energy storage
- contain fats/ lipids
- yellow bone marrow
What is compact or cortical bone?
Hard + dense outer layer of bone
~80% of human skeleton
Comprised of proteins (1/3 bone mass) + hydroxyapatite (2/3 bone mass)
What is spongy/cancellous/trabeculae bone?
Porous + highly vascularised
Storage of bone marrow
Low density + strength
Honeycomb-like structure
What are the openings on the surface of spongy bone called?
Canaliculi
Describe the structure of trabeculae.
Align along positions of stress
Exhibit extensive cross-linking
- for reinforcement + strength
What is bone remodelling?
Formation of new bone to replace old bone
Occurs constantly in growing children
Allows for lengthening/ thickening of bones
When can bone remodelling occur in adults?
(1) Trauma
- fractures
(2) Stress
- weight-bearing exercise
(3) Metabolic changes
- replenishment of calcium stores
What are osteoblasts?
Bone cell type
Essential for bone formation
Cuboidal cells located along the bone surface
Secrete collagen proteins + proteoglycan
- mainly type 1 collagen
Initiate calcification
What are osteocytes?
Bone cell type
Maintain + repair bone
Comprise 90-95% of total resident bone cells
Located within lacunae
Surrounded by mineralised bone matrix
Connected to other osteocytes via canaliculi
When osteocyte dies, surrounding bone dies
What are osteoclasts?
Bone cell type
Breakdown bone
- removal of deteriorating bone
- removal of unnecessary new bone
Large multinucleated cells
- originate from bone marrow
Secrete hydrogen ions
- to dissolve mineral matrix
Secrete hydrolytic enzymes
- to degrade other components of bone
- e.g. collagenase
How can a condition such as osteoporosis be caused?
Imbalance between bone resorption and formation