Degeneration of MSK with Age Flashcards
What comprises the MSK system?
- Bone
- Skeletal muscle
- Chondroid tissues (articular cartilage, IVD, meniscus)
- Fibrous tissues of tendons, ligaments and joint capsule
- Fat
What are the functions of the MSK?
- Enables efficient means of limb movement
- Acts as an endoskeleton for protection and support
- Serves as a reserve for organic and inorganic molecules
- Provides environment for marrow
What are ageing syndromes of MSK?
- Osteoarthritis (joints)
- Osteoporosis (bone)
- Sarcopenia (muscle)
What generic processes occur during MSK ageing?
- Decreasing ammount of tissue
- Altered molecular disposition of the matrix
- Accumulation of degraded molecules
- Reduced efficiency of functional tissue elements
- Reduces synthetic capacity of differentiated cells
- Altered levels of trophic hormones, growth factors and cytokines, or altered ability of cells to respond
- Alterations in the loading patterns of tissues or the tissues response to loading
What other problems can arise with ageing in respect to tissue response to injury?
- Affects balance of mechanisms which ensure homeostasis within organs
- Alters tissue response to injury
- associated with accumulation of genetic damage
- Elicits antagonistic or compensatory mechanisms initially beneficial but chronicity leads to further damage resulting in phenotypic alterations
What cells are in cartilage?
-Chondrocytes
Is cartilage innervated or vascularised?
No
How is articular cartilage reduced with ageing?
- 50% of chondrocytes lost between 40-80 yrs
- Compositional changes with age lead to reduction in water content in ECM (proteoglycans) with fragmentation of protein components and collagen leading to reduced tensile strength
Describe the process of ageing?
- Reduction in osteoblast no. and proliferation
- Less ability of osteoblasts to sense and rerspond to mechanical forces
- Increase in osteoclast no.
- Increased bone turnover and disruption of remodelling activity
With relation to boine ageing, what hormonal changes occur?
- Gradual decline in secreted growth hormone.
- Fall in IGF-1 levels and decreased sensitivity to its effect. (needed for osteoblast differentiation)
- Oestrogen decrease follinng menopause
- Increase in inflammatory cytokines
What is osteoarthritis?
-Disorder of synovial joints which occurs when damage triggers repair processes leading to structural damage within a joint.
What are some risk factors of osteoarthritis?
- Female
- Ageing
Describe the pathogenesis of osteoarthritis?
- Joint damage occurs, triggers repair processes
- These processes alter structure of joint over time causing: localised loss of cartilage, mild synovitis, remodelling of adjacent bone and osteophyte formation.
- Repair processes often leads to structurally altered, non-symptomatic joint, symptoms when repair processes cant fully compensate for damage (MMP’s and IL-1 involved)
How can osteoarthritis be diagnosed?
- 45 or over
- Activity related joint pain
- Either no or short lived morning stiffness
What needs to be managed in osteoarthritis?
-Chronic pain and complex biophyscosocail issues
How can osteoarthritis be managed?
- Agree a mangement plan (exercise, weight loss, suitable footwear)
- Pharmacological: topical, oral or intra articular injections
- Joint surgery for symptoms causing large impact on life quality (last resort)
What are fragility fractures?
-Fractures that result from mechanical forces that wouldnt ordanarily result in fractures
What are the pahses of bone remodelling?
- Activation
- Resorption
- Reversal
- Formation
- Quiescence
What is osteoporosis?
- Low bone mass and microarchitectural deteriation of bine tissues which lead to an increased fracture risk
- Painless, nut complications arent (fragility fractures most feared outcome)
Is it possible for a patient to have osteoarthritis and osteoporosis?
-Less likely to have arthrits and porosis but still possible
What are the risk factors of osteoporosis?
-Fixed: female, ageing, fam history, RA, previous fracture
-Modifiable: smoking, alcohol, low BMI, poor nutrition, lack of exercise
(Longevity of population means it is more prevalent nowadays)
How can osteoporosis be diagnosed?
- Bone strength and density measurements
- DXA scan
- T scores
Do we screen for osteoporosis and why or why not?
Not recommended
- Assess fracture risk using Qfracture
- So we use oppurtunistic case finding and screening of at risk populations done.
What are methods of preventing osteoporosis?
- Maximise peak bone mass
- Healthy diet
- Sufficient Vit D
- Regular weight bearing exercise
- Avoid smoking
- Alcohol in moderation
What are treatments for osteoporosis?
-Antiresorptive: Bisphosphonates (oral and IV) Derosumab (SC) HRT -Anabolic (stimulates formation) Teriparatide (SC)
How does muscle age/decrease?
- Progressive loss of skeletal mass and function
- 3-8%/decade lost after 30yrs old
What is sarcopenia?
-Progressive and generalised skeletal muscle disorder that is associated with increased likelihood of adverse outcomes including falls, fractures, physical disability and mortality.
What playds a key role in development of frailty syndrome?
-Decline in skeletal mass and funtion
How can sarcopenia be categorised?
- Low muscle strength primary parameter
- Physical performace to categorise severity
What type of sarcopenia are there?
-Primary: age related
-Secondary: activity related
disease related
nutrition related
What is the criteria for diagnosis of sarcopenia?
- Low muscle strength
- Low muscle quality or quantity
- Low physical performance
How can sarcopenia be diagnosed?
- Muscle function; handgrip strength, chair stand strength
- Muscle mass; CT/MRI, DXA, Bioimpedance analysis
What is the screening tool used for sarcopenia?
- SARC-F questionairre
- Rate each score 0,1 or 2
- Rates strength, assistance in walking, rise from chair, climb stairs, falls
What are the usual outcomes of sarcopenia?
-Increased mortality, hospitalisation, closely related to physical frailty/ frailty syndrome
What are the treatments for sarcopenia?
- Resistance/aerobic exercise
- Attention to nutrition (increase protein) less evidence
- Vit D supplements
- No pharamlogical therapies yet
What are the potential consequences of MSK ageing?
- Altered gait and balance leading to falls and fear of falls.
- Increased injury/fracture risk
- Chronic pain
- Social isolation if living alone
- Loss of independance
- Care home admission
