M10 Osteoarthritis and Exercise (copy)

osteoarthritis

most common joint disease

• leads to joint pain, swelling, stiffness

  • a result of the body’s failed attempt to repair damaged tissues

  • not just a case of wear and tear

prevalence of OA

more common in older age (42% of Canadian adults 65+ diagnosed with OA)

• greater prevalence in women

Stats Canada 2023-2024

OA and death

OA does not result in death, however some data show a slight inc in mortality due to other causes (e.g. comorbidities)

OA commonality

OA is the most common chronic disease in Canada

• 1 in 5 Canadians have OA (most common form of arthritis) with numbers increasing to 1 in 4

  • close to 1 in 2 when only considering adults age 65+

OA impacts

OA has impacts on a societal level

• $33 billion indirect and direct healthcare costs

• loss of productivity

cartilage

made of chondrocytes which produce ECM (collagen fibers, elastin, proteoglycan)

• poor blood supply and innervation

  • when damaged, cannot heal very well

• allows for frictionless movement at joints and provides cushioning

OA risk factors

non-modifiable

• genetics, age, sex

modifiable

• weight (fat mass), injury, smoking, diet, repetitive movements or chronic strain on joints (e.g. certain professions like construction w/ prolonged bending/crouching)

knee OA

in a healthy knee:

• smooth, thick articular cartilage covering bones

• normal space visible on imaging, cushioning bones

osteoarthritic knee:

• cartilage uneven, worn down, may have fissures, or even complete loss in areas

• decreased joint space due to cartilage loss

types of OA

• knee OA

• hip OA

• hand OA

• spinal OA

spinal OA

bony spurs and narrowed disks compared to healthy spine

• changes in posture, can create significant pain

mechanisms of OA

pressure on joints

overweight

injury

pressure on joints

mechanical stress activates mechanoreceptors, leading to the release of inflammatory cytokines and increased proteolytic enzyme activity

• erosion of cartilage occurs (even more inflammation, viscous cycle)

overweight

weight can increase pressure on joints

• adipose tissue also secretes inflammatory cytokines (Il-ẞ, TNF-alpha, IL-6) activating catabolic enzymes

  • augments cartilage erosion

injury

high load/stress on specific joint compartments (e.g. medial tibio-femoral compartment after ACL tear)

PA and OA risk

moderate PA: no risk associated

intense, competitive sport/PA: inc risk due to inc injury risk and repeated trauma

• PA generally does not inc risk in those already diagnosed with OA

why all the fuss

1. no cure: current treatments focus on symptom management

2. increased risk: increased risk (increased injury risk and increased repeated trauma) with intense competitive sport

3. cycle of chronic pain: significant impact on QoL, leading to decreased PA, increased sedentary behaviour, and potential depression

cycle of chronic pain

chronic pain and reduced QoL (Arthritis Society Toronto) ; OA often leads to a viscous cycle

• Chronic joint pain

• Reduced mobility and function

• Avoidance of physical activity

• Increased sedentary behaviour

• Loss of strength and joint stability

• Potential depression or anxiety related to pain and disability

OA treatment

treatment is mainly about managing symptoms of OA, not curing it

• medication

• physical modalities

• exercise and movement

• supportive devices

• injections

• surgical options

medication

• Acetaminophen – helps reduce pain.

• NSAIDs – reduce both pain and inflammation.

physical modalities

• Ice – decreases swelling and numbs pain.

• Weight loss – reduces joint load, especially in weight-bearing joints.

exercise and movement

• Low-impact exercise (e.g., walking, cycling, swimming)

• Proper joint alignment during physical activity

supportive devices

Braces – help improve alignment and reduce joint stress

injections

Hyaluronic acid injections – improve lubrication and reduce pain (variable effectiveness)

surgical options

• Joint resurfacing surgery

• Osteotomy – realigns bones to reduce abnormal joint loading

• Joint replacement – for severe or end-stage OA

Biver et al 2019

investigated the relationship between gut microbiota and OA risk factors (e.g. obesity, metabolic syndrome, joint injury, inflammation)

• modern life style factors (low PA and diets high in sugar, saturated fats, and low in fiber) contribute to low-grade inflammation and obesity

• habits are associated with microbial dysbiosis

• many of these risk factors are modifiable, suggesting potential pathways for OA prevention or improved management through changes in diet, physical activity, and interventions targeting gut health

dysbiosis

imbalance or disruption in the normal composition of the gut microbiota

• harmful or pro-inflammatory bacteria may increase, while beneficial bacteria decrease

reducing post operative pain

post operation there may be pain

• pharmacological approaches

• interventional/procedural approaches

• importance of anatomy

pharmacological approaches

Opioids – provide systemic pain relief after surgery.

interventional procedural approaches

• Peripheral nerve block (PNB) – anesthetizes specific nerves to reduce pain locally.

  • Key point: Needle placement must be precise to target the correct nerve.

• Radiofrequency (RF) ablation – uses heat to interrupt nerve signals and reduce chronic or post-surgical pain.

  • Key point: Electrode positioning is critical for effective ablation.

medical cannabis

studies suggest CBD/medical cannabis could be used for OA pain

• Animal studies:

  • Cannabidiol (CBD), a component of medical cannabis, may reduce OA-related pain and inflammation (Philpott HT et al., 2017).

• Pre-clinical evidence:

  • Medical cannabis shows potential in managing pain in OA and other chronic diseases (Ko GD et al., 2016)

OA and exercise

exercise can be performed without pain (low-impact activities and modifications to intensity and joint loading)

regular exercise can also improve pain and slow symptom progression

GLA:D

Good Life with Osteoarthritis in Denmark is an evidence-based program for OA management

Focuses on:

• Patient education about OA

• Supervised exercise targeting strength, balance, and joint stability

GLA:D effects

GLA:D shown to:

• Reduce pain

• Improve mobility and physical function

• Support long-term self-management

Alkatan et al 2016

Purpose: Test if 12 weeks of swimming or cycling can reduce OA joint pain and stiffness and improve function and QoL.

Goal: Determine if low-impact aerobic exercise is a safe and effective way to manage OA symptoms and improve functional capacity

Alkatan et al methods

• Design: Randomized controlled study, 12 weeks

• Participants: 48 adults with mild-to-moderate OA

• Groups: Swimming vs cycling

• Exercise: 45 min/session, 3x/week, 60–70% HR reserve

• Outcomes: WOMAC for pain, stiffness, function; handgrip, knee strength, 6-min walk test

Alkan et al results

• Both groups: reduced pain and stiffness, improved function

• Increased strength and 6-min walk distance (~15–30%)

• No difference between swimming and cycling

• Quality of life also improved

Alkan et al discussion

• Both exercise groups (swimming and cycling) showed significant reductions in joint pain, stiffness, and physical limitations (all p < 0.05).

• Both groups also had significant improvements in functional capacity: handgrip strength, isokinetic knee extension/flexion power increased by ~15‑30%, and distance covered in 6‑minute walk test increased.

• There were no significant differences in the magnitude of improvement between the swimming and the cycling groups (i.e., both modes were similarly effective).

• Additional benefit noted: improvements in quality of life accompanying pain/functional gains.

Alkan et al conclusion

• The authors suggest that non–weight‑bearing aerobic exercise (like swimming or cycling) is feasible and effective for OA patients, especially those who may have difficulty with weight‑bearing activity due to pain or joint load

• They highlight the buoyancy of water (in swimming) as particularly beneficial since it reduces joint loading; however, cycling (land‑based but non–weight bearing) produced similar improvements, suggesting the key aspect may be aerobic, low‑impact training rather than the environment per se.

• They discuss concerns in OA that increased physical activity might increase “wear and tear” of joints, but their findings challenge that notion—showing improvements rather than deterioration.

• Limitations: The study duration was 12 weeks (short‑term), participants had moderate OA (grade I–III) so generalizability to severe OA (end‑stage) is unclear; and adherence in longer term isn’t addressed.

Foucher et al 2021

Purpose:
Examine how walking energetics (i.e., the metabolic cost of walking) and hip abductor muscle strength are related to physical activity levels in older women who have hip osteoarthritis (OA).

Goal:
Determine whether inefficient walking (higher energy cost) and weaker hip abductors are key factors limiting physical activity in hip‑OA patients — which could inform targeted rehabilitation strategies

Foucher et al methods

• Design: Cross‑sectional observational study. PMC+1

• Participants: Older women with hip OA (exact number/sample details not given in the summary I found). ScienceDirect

• Measures: Walking energetics (likely oxygen consumption or metabolic cost during walking), hip abductor muscle strength, and self‑reported or objectively measured physical activity level.

• Analytical approach: Associations between walking cost, abductor strength and physical activity were tested.

Foucher et al results

• Higher walking energy cost (less efficient walking) was significantly associated with lower physical activity in women with hip OA

• Lower hip abductor strength was also linked to reduced physical activity

• These two factors (energetics + abductor strength) together help explain why some hip OA patients might be less active

Foucher et al discussion

• Authors propose that hip OA, biomechanical inefficiencies — such as weak hip abductors and altered gait requiring more energy — may reduce physical activity because walking becomes more “costly” (fatiguing or uncomfortable).

• They suggest that rehabilitation programs for hip OA should target hip abductor strengthening and improve gait efficiency (perhaps via gait training, assistive devices, or targeted exercise) to increase activity participation.

• They also discuss that increased physical activity is important for overall health and for slowing OA progression, so addressing these limiting factors could have broader benefits.

• Limitations discussed include the cross‑sectional design (cannot infer causation), possible measurement limitations, and the fact the sample was older women only (so generalizability to men or younger patients may be limited)