What is osteoarthritis?

Osteoarthritis (OA) is the most common joint disease globally — characterised by progressive degradation of articular cartilage, subchondral bone changes, osteophyte formation and synovial inflammation. It is not simply "wear and tear" — OA involves the whole joint and has significant inflammatory and metabolic components. Most commonly affected: knees (most prevalent); hips; hands (DIP/PIP/thumb base); spine. It is the leading cause of musculoskeletal disability in adults over 45.

Does paracetamol work for OA?

No — not meaningfully. Paracetamol was the standard first-line OA analgesic for decades based on safety assumptions rather than efficacy evidence. Cochrane 2016 and the ALAN network meta-analysis (Lancet 2016) showed paracetamol provides only minimal, clinically non-meaningful benefit vs placebo for OA pain. NICE 2022, OARSI 2019 and EULAR have all either removed or significantly downgraded paracetamol recommendations for OA. Exercise and weight loss are the evidence-based core treatments.

What is the best exercise for knee OA?

All forms of exercise reduce knee OA pain — the best exercise is the one the patient will do consistently. Evidence supports: quadriceps strengthening (wall squats, leg extensions — reduces knee load by improving dynamic joint stability); aerobic exercise (walking, cycling, swimming); aquatic exercise (reduced joint load with resistance — good for severe pain or obesity); Tai Chi (Cochrane evidence). NICE recommends exercise as a core treatment for ALL OA. A 12-week supervised programme followed by independent continuation produces the best long-term outcomes.

When is joint replacement needed?

TKR/THR should be considered when: significant OA is confirmed on imaging; pain and disability are severe; conservative management (exercise, weight loss, physiotherapy, NSAIDs) has been adequately tried and failed. No specific age threshold — decision is based on functional impact and surgical fitness. TKR/THR are among the most cost-effective procedures in medicine — >90% 10-year implant survival, 80-85% patient satisfaction. Cautions: very high BMI (>40) increases revision risk; severe depression/anxiety predicts worse satisfaction.

Are there disease-modifying OA drugs?

Currently: no approved DMOAD (disease-modifying OA drug). Unlike RA, nothing reliably slows or reverses OA progression in clinical practice. Tanezumab (anti-NGF) was withdrawn — associated with rapidly progressive OA. Sprifermin (FGF-18 for cartilage stimulation) and lorecivivint are in Phase 3 trials. Management is currently symptomatic and function-preserving.

How does GMJ News cover osteoarthritis?

GMJ News covers the WHO 2023 burden (600M), paracetamol downgrade, exercise as first-line core treatment, weight loss and adipokine mechanisms, topical vs oral NSAIDs, intraarticular injections (short-term steroids), opioid avoidance, TKR/THR indications, anti-NGF withdrawal lesson, and OA as a metabolic-inflammatory disease. Osteoarthritis — the world's most common joint disease — is central to PHIG's NCD and ageing population programme.

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Osteoarthritis

GMJ News knowledge hub · last reviewed August 2026 · Georgian Medical Journal

Summary Statistics Glossary GMJ news FAQ Documents Organizations Research

Osteoarthritis (OA) — the progressive loss of articular cartilage with secondary bone changes, osteophyte formation and synovial inflammation — is the most common joint disease globally, affecting an estimated 600 million people (WHO 2023 global burden update), with the knee being the most prevalent site and a leading cause of disability, work absence and reduced quality of life in adults over 45, representing one of the largest contributors to years lived with disability of any musculoskeletal condition (WHO 2023). A major clinical rethink is underway: paracetamol (acetaminophen) — for decades the standard first-line OA analgesic — is now considered of minimal benefit by multiple Cochrane reviews and NICE has downgraded its recommendation; exercise and weight loss are now recognised as the most evidence-based core interventions, reducing knee OA pain as effectively as NSAIDs with none of the long-term cardiovascular and GI risks.

Key messages

600 million people — most common joint disease globally (WHO 2023)

WHO 2023 global burden update: osteoarthritis affects approximately 600 million people — the most common joint disease on earth. Knee OA is the most prevalent form, followed by hip and hand OA. OA is the leading cause of pain-related disability in adults over 45 and will increase as populations age and obesity rises.

Paracetamol is out — exercise and weight loss are the evidence-based core

Paracetamol (acetaminophen) — the historical first-line analgesic for OA — is no longer recommended by NICE (2022), EULAR or OARSI as a routine treatment: Cochrane review (2016) and updated meta-analyses confirm minimal clinically meaningful benefit over placebo for OA pain. Exercise (quadriceps strengthening, aerobic, aquatic) and weight loss (for overweight patients) reduce OA pain as effectively as NSAIDs with a superior long-term safety profile.

Weight loss — the most impactful intervention for knee OA

Each 1kg weight loss reduces the knee joint load by approximately 4kg during walking. A 10% body weight loss in obese patients reduces knee pain by approximately 50% in observational studies. The IDEA trial (2013): diet + exercise produced significantly better knee pain and function than exercise alone. Weight loss reduces the inflammatory adipokine load (leptin, adiponectin, TNF) from adipose tissue — a mechanism beyond simple mechanical offloading.

NSAIDs — effective but long-term risks are real

Oral NSAIDs (diclofenac, naproxen, celecoxib) are the most consistently effective pharmacological treatments for OA pain — superior to paracetamol and tramadol. Topical NSAIDs (diclofenac gel) provide equivalent efficacy for knee OA with dramatically lower systemic side effects and are preferred in elderly patients. All oral NSAIDs should be used at the lowest effective dose for the shortest duration.

Intraarticular injections — short-term benefit, carefully selected

Corticosteroid injections: reduce OA pain for approximately 4-8 weeks; useful for acute flares. May accelerate cartilage loss with frequent injections (NEJM 2017). Hyaluronic acid: controversial — NICE does not recommend; EULAR assigns low evidence grade. PRP: insufficient evidence.

Total knee/hip replacement — highly effective for severe OA

TKR/THR are among the most cost-effective surgical procedures for severe OA not responding to conservative management. TKR 10-year implant survival: approximately 90-95%. Patient satisfaction: approximately 80-85% excellent or good outcomes. Timing: TKR is less effective in the very obese (BMI >40) or those with severe pre-operative depression.

Key statistics

600M

people globally affected by osteoarthritis (WHO 2023 updated burden)

WHO 2023

Paracetamol

no longer recommended as routine OA treatment by NICE 2022, EULAR, OARSI

NICE 2022/Cochrane

4kg load

reduction in knee joint load per 1kg body weight loss

Biomechanics

Topical NSAIDs

equivalent efficacy to oral NSAIDs for knee OA with lower systemic risk

Cochrane/NICE

4-8 weeks

intraarticular corticosteroid benefit duration

NEJM/OARSI

90-95%

10-year implant survival for total knee/hip replacement

NJR/NHS

Osteoarthritis treatment — evidence strength by intervention (OARSI/NICE 2022)

Source: OARSI/NICE 2022. Exercise and weight loss are the highest-evidence core treatments; paracetamol is no longer recommended.

Glossary of key terms

Kellgren-Lawrence grading
RadiologyRadiological severity grading for OA: Grade 0 — normal; Grade 1 — doubtful narrowing + possible osteophytes; Grade 2 — definite osteophytes + possible narrowing; Grade 3 — moderate osteophytes + definite narrowing + sclerosis; Grade 4 — large osteophytes + marked narrowing + severe sclerosis. Grade does not always correlate well with symptoms.

Heberden's and Bouchard's nodes
ClinicalBony swellings at DIP joints (Heberden's nodes) and PIP joints (Bouchard's nodes) — representing osteophytes in hand OA. Common in post-menopausal women; strong genetic predisposition. Distinguished from RA (which spares DIP joints and causes MCP involvement).

Adipokines and OA
PathophysiologyOA is not purely mechanical. Adipose tissue (particularly infrapatellar fat pad) secretes pro-inflammatory adipokines (leptin, adiponectin, resistin) driving chondrocyte apoptosis and matrix metalloprotease expression. This explains why OA affects hand joints not under mechanical load in obese patients — the metabolic-inflammatory component is systemic.

Opioids in OA — not recommended
NICE/OARSIOpioids (tramadol, codeine) should not be used for osteoarthritis — strong recommendation in all major guidelines (NICE 2022, OARSI 2019). Risks outweigh modest short-term benefits: tolerance, dependence, falls, cognitive impairment in elderly. Tramadol associated with increased mortality in elderly OA patients vs NSAIDs in observational studies.

Sarcopenic obesity and OA
Geriatrics/RheumatologyThe combination of low muscle mass (sarcopenia) and obesity substantially increases OA risk — patients lose the protective effect of muscle strength on joint loading, while bearing excess adipokine-mediated inflammation. Resistance exercise and protein supplementation alongside weight loss provides better OA outcomes than weight loss alone.

Exercise programmes for OA
Cochrane/NICECochrane 2015 (54 RCTs, 3,913 participants): exercise produces clinically significant pain reduction (SMD -0.49) and function improvement in knee OA. No single type is superior — quadriceps strengthening, aerobic exercise and aquatic exercise all have evidence. NICE: exercise is a core treatment for ALL OA regardless of age, comorbidities or pain level.