Session 3: Clinical Effects of the Ageing Musculoskeletal System

Resorption

Osteoclasts break down bone tissue

Bone formation

Osteoblasts form a matrix to replace resorbed bone with new bone

Vertebral fracture

Curvature of the spine and loss of height

Pain, breathing difficulties, GI problems and difficulties in performing ADLs

Majority of vertebral fractures (50-70%) do not come to clinical attention.

Osteoporosis

Systemic skeletal disease characterised by low bone mass and microarchitectural deterioration of bone tissue leading to...

- Increased bone fragility

- Increased risk of fracture

Non-modifiable risk factors of osteoporosis

Age

Female sex

Ethnicity (caucasians)

Previous fractures

Family history

Late menarche (>16 years old), early menopause (<47 years old)

Modifiable risk factors of osteoporosis

Bone mineral density

Alcohol (>3.5 units/day).

Weight BMI <20

Smoking

Physical inactivity

Medication risk factors of osteoporosis

Long term antidepressants

Antiepileptics

Aromatase inhibitors

Long-term DMPA

GnRH agonists

PPIs

Oral glucocorticoids

Thiazolidindione for DM TZDs

Name some endocrine conditions which are associated with increased risk of osteoporosis

Diabetes mellitus

Hyperthyroidism

Hyperparathyroidism

Hyperprolactinaemia

Cushing's disease

Menopause

Hypogonadism

Androgen deprivation therapy

Treatment with aromatase inhibitors

Name some neurological conditions which are associated with increased risk of osteoporosis

Alzheimer's

Parkinson's

Multiple sclerosis

Stroke

Name some other conditions that are associated with an increased risk of osteoporosis

Rheumatoid arthritis

Systemic lupus erythematosus

Inflammatory bowel disease

Cystic fibrosis

Epilepsy

HIV

Depression

Asthma

Chronic kidney disease

Bone mineral density (BMD)

Expressed as T-score which is the number of SD below the mean BMD of young adults at their peak bone mass

Normal BMD

T-score of -1 SD or above

Osteopenia BMD

T-score of -1 to -2.5 SD

Osteoporosis BMD

T-score of -2.5 SD or less

Established severe osteoporosis

T-score of -2.5 SD or below with one or more associated features

How is osteoporosis diagnosed?

DEXA scan (dual energy x-ray absorptiometry)

Fragility fractures

Fractures that result from mechanical forces that would not ordinarily result in a fracture, known as low-level trauma e.g., fall from standing height or less

Risk factors for fragility fractures

Reduced bone density

Oral/systemic glucocorticoids

Age

Sex

Previous fractures

Family history of osteoporosis

Interventions (lifestyle) for osteoporosis

Static/dynamic weight bearing exercise (low and high force)

Muscle resistance training and balance

Interventions (diet) for osteoporosis

Supplementation with 10 micrograms/day of vitamin D (400 IU)

Dietary calcium

Vitamin B, Vitamin K

Reduce salt intake

Balanced diet

Osteoblast

Cells that form new bones and grow and heal existing bones

Osteoclast

Cells that degrade bone to initiate normal bone remodelling and mediate bone loss in pathological conditions by increasing their resorptive activity

Consequences of hip fractures

High mortality rate

High morbidity rate

PE/DVT/CVA/MI

Pressure sores

Chest infections/UTIs

Confusion

What is OA (NICE)

Osteoarthritis is defined by NICE as a disorder of synovial joints, that is characterised by...

- Focal areas of damage to the articular cartilage

- Remodeling of underlying bone at the formation of osteophytes - new bone at joint margins

- Mild synovitis

Clinical features of OA

Pain

Stiffness

Deformity

Joint swelling

Heberden's nodes

Bouchard's nodes

Radiological features of OA

Loss joint space

Osteophytes

Sclerosis

Subchondral cysts

Treatment of OA

NON-OPERATIVE

- Weight loss

- Exercise/physio

- Analgesia/NSAIDs

- Joint injection

OPERATIVE

LOCAL complications of a hip replacement

Leg length inequality

Dislocation

Infection

Loosening (after 10-15 years)

Neurovascular damage...

- Sciatic/femoral nerve damage

- Common peroneal nerve TKRs

- Other nerves: inferior/superior gluteal nerves

SYSTEMIC complications of a hip replacement

UTIs/chest infections

Clinical DVT

Non-fatal PE

Fatal PE

Mortality

Frailty in the musculoskeletal system is often correlated with two other major geriatric syndromes, what are they?

Sarcopenia

Cachexia

Sarcopenia

Syndrome characterised by progressive and generalised loss of skeletal muscle mass and strength, with a risk of adverse outcomes such as physical disability, poor quality of life and death

Diagnosis of sarcopenia

Diagnosis is based on documentation of criterion 1 plus (criterion 2 or criterion 3)

1) Low muscle mass

2) Low muscle strength

3) Low physical performance

Pathogenesis of sarcopenia

- Muscle homeostasis is maintained in a delicate balance between new cell formation, hypertrophy and protein loss

- This balance is coordinated by the brain, endocrine system & immune system and is influenced by nutritional factors and levels of physical activity

- The adverse neurological, endocrine and immune components of frailty have the potential to upset this delicate homeostatic balance and accelerate the development of sarcopenia

Frailty

Frailty is a medical syndrome with multiple causes and contributors that is characterised by diminished strength, diminished endurance, reduced physiological function that increase individuals' vulnerability for developing increased dependency and/or death

What factors increase fall risk

- Decreased mobility

- MSK-related posture & gait changes

- Neuro-related gait & proprioception changes

- Environmental hazards

Potential interventions for frailty

1) Exercise = positive impact on MSK, endocrine and immune systems

2) Nutritional intervention = caloric and protein support and vitamin integration

3) Reduction of polypharmacy = STOPP and START criteria