Osteoarthritis (OA) (2026)

Osteoarthritis (OA) is along-term disorder of synovial joints involving a cycle of normal wear, alongside repair and remodelling (NICE, 2023;Badlissi, 2024).   

It is a multifactorial dynamic process with influences including age, genetics, biochemical and biomechanical factors, trauma history and lifestyle (NICE, 2023;Badlissi, 2024).

Features in the knee include meniscal changes, localised cartilage loss, remodelling of adjacent bone and involvement of periarticular ligaments and synovium and formation of osteophytes (NICE, 2023;Badlissi, 2024; Sharma, 2025).

OA does not always progress to more severe disease and structural changes on an x-ray do not necessarily correspond well to symptoms (NICE, 2023). 

A flare of OA describes a sudden, sustained increase in symptoms for at least 24 hours which typically lasts 3-8days (NICE, 2023;Badlissi, 2024).

Globally, cases of knee OA are projected to rise 74.9% between 2020 and 2050 (Steinmetzet al., 2023).

OA diagnosis increases sharply between 45–64 years of age, peaking at 75–84 years of age (NICE, 2023).

2 out of 3 people with OA (at any joint) have at least one other co-morbid medical condition- most commonly hypertension, dyslipidaemia, back pain, thyroid conditions and depression. Multi-morbidity is common. Overweight and obesity are risk factors for both incidence and progression of knee OA (Hinman et al., 2022).

Physical Inactivity

Biological:

1. Increasing age >45

2. Female (>Male)

3. Overweight/obese

4. Low bone density

5. Genetics

Physical/biomechanical:

1. Previous injury/damage

2. Altered biomechanics

3. Exercise/occupational stresses

(Zhang et al., 2010; NICE, 2023; Dong et al., 2023)

Can affect medial tibiofemoral, lateral tibiofemoral, or patellofemoral compartments, or a combination of these, with pain often localised to affected compartment(s) (NICE, 2023).

May have:

• giving way symptoms (usually through patellofemoral involvement/ weakness of quads or pain inhibition),

• locking (consider loose body/meniscal tear)

• crepitus.

                             (NICE, 2023)

Possible findings include:

-Reduced range of motion with reproduction of pain

-Crepitus

-Joint line tenderness of affected compartment(s)/ pain on patellofemoral compression

-Bony enlargement of femoral condyles and lateral tibial plateau

-Antalgic gait

-Varus or (less commonly) valgus deformity

-Absent or modest effusion

- Muscle wasting and weakness

                                                 (Zhang et al., 2010; NICE, 2023)

NICE (2023) recommends diagnosis clinically in individuals >= 45 with:

• Activity related joint pain and

• No early morning stiffness OR early morning stiffness <=30 mins

Other criteria includes EULAR (European Alliance of Associations for Rheumatology) recommending clinical diagnosis in individuals > 40 years of age with:

• Movement related knee pain,

• Morning stiffness less than 30 minutes

• Functional limitations

• Plus one or more typical examination findings (crepitus, restricted movement, bony enlargement) (Zhang et al., 2010)

A study in 2024 (Wang et al., 2024) compared the EULAR, NICE and American College of Rheumatology (ARC) criteria against expert diagnosis of clinically relevant knee OA. The study found that limitations exist in all the criteria mentioned and only moderate diagnostic agreement was found between them. Additionally, it was recognised that, just as OA symptoms often fluctuate over time, so too does the fulfilment of the above criteria at different time points so a degree of clinical judgement is required.

(NICE, 2022; NICE, 2023; Badlissi, 2024)

 (NICE, 2022)

Major international guidelines recommend education as part of OA management plans. (Bannuru, et al., 2019; NICE, 2023; Moseng et al., 2024)

Recommendation:

Suggestions for possible focus in patient education sessions could include the following (as applicable):

• knee anatomy

• pathophysiology of knee OA,

• risk factors for knee OA,

• epidemiology of knee OA,

• diagnosis of knee OA,

• symptoms of knee OA,

• biopsychosocial nature of pain,

• self-management strategies,

• exercise therapy,

• weight loss,

• medical management

• surgical management

• adjunct options                                                    (Goff et al., 2022)

Basis for recommendation (for info) at end of document

Exercise therapy is recommended in national and international guidelines and should be tailored to the patient (Bannuru, 2019; NICE, 2023; Moseng et al., 2024).

Recommendation: A 2023 consensus article from OARSI (OA Research Society International) aimed to provide guidance around best practice therapeutic exercise for OA of the hip and / or knee and developed 11 domains and subdomains of recommendations (Holden et al., 2023). The main domains are listed below (see article for subdomains):

• Consider exercise in the context of living with OA and pain: a program that promotes a sustainable active self-management

• Undertake a comprehensive baseline assessment with follow-up

• Set goals: SMART

• Consider the type of exercise: incorporate strategies to optimise physical activity levels

• Consider the dose of exercise: aim for a long-term rather than episodic approach to exercise participation

• Modify and progress exercise- provide clear guidance

• Individualise exercise focusing on the whole person, not just the affected joint

• Optimise the delivery of exercise ensuring the person is confident in their ability to carry it out

• Focus on exercise adherence addressing barriers and facilitators early

• Provide education about OA and the role of exercise- use a positive approach and lay terminology that reduces fear of exercise

                                                                                                                                                                                           (based on Holden et al., 2023)

Basis for recommendation (for info) at end of document

NICE (2023) recommends consideration of manual therapy (such as manipulation/ mobilisation/ soft tissue techniques) in knee OA patients only alongside therapeutic exercise and with clear discussion explaining that there is not enough evidence to support its use alone for managing osteoarthritis. They mentioned similar treatment durations to exercise interventions (less than 3 months) having been used in studies. They further stipulate that clinical and economic evidence shows that exercise alone was more effective than both manual therapy by itself or manual therapy combined with exercise. There was an acknowledgement of need for further high-quality studies in this area.

A 2025 systematic review and meta-analysis by Lin et al. Looked at pooled results from 23 RCT’s involving 996 participants concluding that mobilisations with movement (MWM) reduces pain and disability in individuals with knee OA especially when incorporated into treatment protocols featuring weightbearing positions and combined physical therapy approaches. They acknowledged limited follow-ups and potential for bias; the full article could not be obtained for further scrutiny so this guidance should be used with caution.

CSI can be a therapeutic option for knee OA in specific circumstances.

NICE (2023) guidance on CSI use for OA advises consideration when other pharmacological treatments are ineffective or unsuitable or to support therapeutic engagement in exercise. The patient should be informed that any benefits are short term 2-10 weeks. NICE have acknowledged that further research is required to inform recommendations around CSI usage.

A national cohort study of England was published in 2025 by Hawley et al. It utilised a large data set to further explore potential impact on outcomes, with longer-term follow up, from CSI for knee joint OA. Findings were unclear and not fully supported by secondary analysis but may indicate lower rates of TKR over 5 years follow up from CSI.

There is unclear evidence around repeated CSI usage in the knee and risks of deleterious progression of OA changes.

In NHSGGC there is agreement between surgeons that CSI should not be completed within 6 months of any planned surgical intervention.

Weight Loss:

NICE (2023), and other international guidance sources, recommends weight loss for people with knee OA who are overweight/ obese; with recommendations around:

• discussing potential benefits re: symptoms and quality of life

• explanation that any amount of weight loss likely to be beneficial (with possible changes including changes to inflammatory factors) but losing more would have more benefits- and aiming for 10% likely to be better than aiming for 5% weight loss

Walking aids:

• Can improve safety and independence

• Can reduce weight bearing on affected joint in more advanced cases where this might be the goal

                                                                                                                                                                             (NICE, 2023)

• Acupuncture or dry needling.

• Electrotherapy treatments,

• Insoles, braces, tape, splints or supports being routinely provided

                                                                                  (NICE, 2023)

Sedentary behaviours and poor physical activity can lead to an increased risk of falls, particularly for people with knee OA (Hinman et al., 2023)

If msk presentation and unclear diagnosis or not progressing as expected consider options:

• discus with peer (for band 6/7 staff) 

• senior (band 5/6/7 staff) 

• present at case review as per guidance

• consider for APP review as per guidance

NICE (2023) guidance for OA Imaging ‘do not routinely arrange an X-ray of the affected joint(s) to diagnose OA’.

BMJ Best Practice advice is that OA is essentially a clinical diagnosis. Both guidance sources agree that imaging (initially XR imaging) should be considered if there is:

• Diagnostic uncertainty

• Sudden or unexpected worsening

                                 (Badlissi, 2024)

For info, radiopaedia advises the following views: “The initial study of any patient with suspicion of knee osteoarthritis should include a Rosenberg view, a PA radiograph with weight-bearing and 45 degrees of flexion, which is more sensitive to detect joint space narrowing.” (Sharma, 2025)

Please note that msk APP’s and primary care APP’s cannot request specific views

Discuss as applicable with peer/ senior clinician/ case review

Consider:

• If has clinical OA and appropriate imaging supports this (ortho may require up to date imaging; this might need repeated if previous imaging ≥1 year)

• If conservative management / physio intervention failed to improve symptom

• Only refer on if the patient wishes to consider surgical intervention

• Would help if the patent is sign posted to 'How a knee replacement is done - NHS' or NHS inform guide on Knee replacement

GGC-MSK Physiotherapy - Documents - OA Pathway - All Documents 

Badlissi, F. (2024) Osteoarthritis. BMJ Best Practice. Available online at https://bestpractice.bmj.com/topics/en-gb/192 [Last accessed 19/01/26]

Biswas, I., Nalbant, G., Lewis, S., Chattopadhyay, K. (2024) Key characteristics of effective yoga interventions for managing osteoarthritis: a systematic review and meta-analysis. Rheumatology international. Vol 44(9) pp. 1647–1677. Available online at doi: 10.1007/s00296-024-05652-y. [Last Accessed 05/02/26]

Dong, Y., Yan, Y., Zhou, J., Zhou, Q., Wei, H. (2023) Evidence on risk factors for knee osteoarthritis in middle-older aged: a systematic review and meta analysis, Journal of Orthopaedic Surgery and Research, 18(1) 634. Available online at https://pubmed.ncbi.nlm.nih.gov/37641050/ [Last accessed 28/01/26]

Fransen, M., McConnell, S., Harmer, A.R. (2015) Exercise for osteoarthritis of the knee: a Cochrane systematic review. British Journal of Sports Medicine. Vol 49.pp 1554- 1557. Available online at: doi:10.1136/bjsports-2015-095424 [Last Accessed 29/01/26]

Goff A.J., De Oliveira Silva D., Merolli M., et al. (2021) Patient education improves pain and function in people with knee osteoarthritis with better effects when combined with exercise therapy: a systematic review. Journal of Physiotherapy Vol 67(3). pp177-189. https://doi:10.1016/j.jphys.2021.06.011 [Last Accessed 28/01/26]

Goff, AJ., de Oliveira Silva, D., Ezzat A.M., et al. (2022) Knee Osteoarthritis Education Interventions in Published Trials Are Typically Unclear, Not Comprehensive Enough, and Lack Robust Development: Ancillary Analysis of a Systematic Review. Journal of Orthopaedic & Sports Physical Therapy. Vol.52(5). pp 276-286. Available online at: https://doi:10.2519/jospt.2022.10771 [Last Accessed 28/01/26]

Guo, J., Peng, C., Hu, Z. et al. (2022) Effect of Wu Qin Xi exercises on pain and function in people with knee osteoarthritis: A systematic review and meta-analysis. Frontiers in Medicine. Vol 7 (9) Article 979207. Available online at: doi: 10.3389/fmed.2022.979207 [Last Accessed 05/02/26]

Hamada, K., Tamura, H., Hirohama, K et al. (2022) The effectiveness of group education in people over 50 years old with knee pain: A systematic review and meta-analysis of randomized control trials. Musculoskeletal Science and Practice, Volume

62,102627, https://doi.org/10.1016/j.msksp.2022.102627 [Last Accessed 28/01/26]

Hawley, S., Prats-Uribe, A., Matharu, G.S. et al. (2025) Effect of intra-articular corticosteroid injections for knee osteoarthritis on the rates of subsequent knee replacement and post-operative outcomes: a national cohort study of England. BMC Medicine. Vol 23(1):195. Available at: doi: 10.1186/s12916-025-04000-6. PMID: 40189536; PMCID: PMC11974133. [Last Accessed 29/01/26]

Hinman, R.S., Hall, M., Comenmsoli, S., Bennell, K.L. (2022) Exercise & Sports Science Australia (ESSA) updated Position Statement on exercise and physical activity for people with hip/knee osteoarthritis, Journal of Science and Medicine in Sport, 26 (1) 37- 45. Available online at https://www.jsams.org/article/S1440-2440(22)00492-3/fulltext [Last accessed 19/01/26]

Holden M.A., Metcalf B., Lawford B.J. et al. (2023) Recommendations for the delivery of therapeutic exercise for people with knee and/or hip osteoarthritis. An international consensus study from the OARSI Rehabilitation Discussion Group. Osteoarthritis Cartilage. 2023 Mar;31(3):386-396. doi: 10.1016/j.joca.2022.10.009. Epub 2022 Oct 28. PMID: 36367486.

Lawford B.J., Hall M., Hinman R.S. et al. (2024) Exercise for osteoarthritis of the knee. Cochrane Database of Systematic Reviews. 12. Available online at: https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD004376.pub4/full [Last Accessed 28/01/26]

Lawford, NB.J., Bennell, K.L., Spiers, L. et al. (2025) Relationship Between Number of Different Lower-Limb Resistance Exercises Prescribed in a Program and Exercise Outcomes in People With Knee Osteoarthritis: A Systematic Review With Meta-Regression. Arthritis care & research. Vol. 77(5), pp. 594–603. Available online at DOI: 10.1002/acr.25476 [Last Accessed 05/02/26]

Lin, L.H., Lin, M., Hsieh, G.J. et al. (2025) Mobilization with movement on reducing pain and disability for knee osteoarthritis: a systematic review and meta-analysis or randomized controlled trials. Journal of Manual and Manipulative Therapy. Apr pp. 1-16. Available at: DOI: 10.1080/10669817.2025.2495576. [Last Accessed 29/01/26]

Luan, L., Elansary, D., Adams, R. et al. (2022). Knee osteoarthritis pain and stretching exercises: a systematic review and meta-analysis. Physiotherapy. Vol 114, pp. 16–29.

Moseng, T., Vliet Vlieland, T.P.M., Battista, S. et al. (2024) EULAR recomendations for the non –pharmacological core management of hip and knee osteoarthritis: 2023 update. Annals of the Rheumatic Diseases. Vol 83(6). Pp. 730-740

NICE (2023) Osteoarthritis. Available online at https://cks.nice.org.uk/topics/osteoarthritis/ [Last accessed 19/01/26]

NICE CKS (2022) Knee pain – assessment; diagnosis; non-traumatic causes. Available online at: https://cks.nice.org.uk/topics/knee-pain-assessment/diagnosis/non-traumatic-causes/ [Last Accessed 28/01/26]

Qi, W., Alarcon, D., Arenilla, M.J. et al. (2025) A Systematic Review and Meta-Analysis of Asian Exercise Techniques and Various Physical Activity Interventions in Middle and Late Adulthood Patients With Knee Osteoarthritis. Journal of Aging and Physical Activity. Vol 33(4) pp. 387- 398. Available online at: doi: 10.1123/japa.2024-0077 [Last Accessed 05/02/26]

R.R. Bannuru, M.C. Osani, E.E. Vaysbrot, N.K. Arden, K. Bennell et al. (2019) OARSI guidelines for the non-surgical management of knee, hip, and polyarticular osteoarthritis. Osteoarthritis and Cartilage, Vol 27 (11), 1578-1589, https://doi.org/10.1016/j.joca.2019.06.011 [Last Accessed 28/01/26]

Sharma, R. (2025) Osteoarthritis of the knee. Available at: https://radiopaedia.org/articles/osteoarthritis-of-the-knee (Accessed 29/01/26)

Steinmetz, J., Culbreth, G., Vos, T. (2023) Global, regional, and national burden of osteoarthritis, 1990–2020 and projections to 2050: a systematic analysis for the Global Burden of Disease Study 2021, The Lancet Rheumatology. Vol 5(9), e508- e522. Accessed online at https://www.thelancet.com/journals/lanrhe/article/PIIS2665-9913(23)00163-7/fulltext [Last accessed 28/01/26]

Wang, Q., Runhaar, J, Kloppenburg, M. et al. (2024) Evaluation of the Diagnostic Performance of American College of Rheumatology, EULAR, and National Institute for Health and Clinical Excellence Criteria Against Clinically Relevant Knee Osteoarthritis: Data From the CHECK Cohort. Arthritis Care & Research. Vol 76(4). pp. 511- 516

Zhang, W., Doherty, M., Peat, G., et al (2010) EULAR evidence-based recommendations for the diagnosis of knee osteoarthritis. Annals of the Rheumatic Diseases. Vol 69. pp. 483- 489. Available online at: https://ard.bmj.com/content/annrheumdis/69/3/483.full.pdf [Last Accessed 28/01/26]

Self-help information - Knee Pain - NHSGGC

NHS GGC OA information video link

NICE Management of osteoarthritis leaflet

Flippin' Arthritis video link

The NICE (2023) guidelines recommend education be considered as part of a treatment package for patients with knee OA; but some may not require education or a behaviour change approach in addition to exercise.

Systematic reviews would seem to indicate positive outcomes from education interventions combined with exercise (Goff et al., 2021; Hamada et al., 2022)

There has been criticism of disparity in education interventions used in trials; this makes it difficult to set clear recommendations for clinical practice. In the absence of clear direction, the list of topics clinicians might wish to consider has been suggested (see education section in pathway) (Goff et al., 2022).

A 2023 OARSI (OA Research Society International) consensus study discussed the importance of co-developing a flare up management plan, which could help self-management and exercise adherence in the longer term (Holden et al., 2023)

Therapeutic exercise might aim to improve muscle strength and function, balance and neuromotor control, joint range of motion and aerobic fitness; with research supporting potential for positive changes on pain, physical function and quality of life (Bannuru, 2019; NICE, 2023; Moseng et al., 2024; Lawford et al., 2024)

Exercise can also help modify:

• weight and blood chemistry and affect changes in joint cartilage, other mechanisms of potential positive effects.

• psychology and self-efficacy, including reducing fear of movement and facilitating better functioning.

• can reduce OA fatigue further boosting function and participation/ social functioning

• exercise can be supervised, unsupervised, or a combination of both (clinical benefits possibly greater when supervised). Can use land and water-based exercises (water based being mainly useful where pain or poor mobility limit on land options) (Moseng et al., 2024)

Challenges:

• it has been recognised that the delivery therapeutic exercise for OA is multidimensional and complex (Holden et al., 2023).

Strengthening:

• Muscle weakness is common in OA. Strength training of sufficient dosage can address muscle weakness by improving muscle mass and/ or recruitment

Increased strength may:

• alter joint forces and biomechanics

• reduce pain

• improve physical fitness and functioning  (Fransen et al., 2015)

• there is support for training both hip and quadriceps muscle groups for those with knee OA aiming to improve walking function (Hinman et al., 2023).

Aerobic exercise:

• Low impact exercise might be better tolerated in those with significant symptoms. If walking is used >6000 steps/ day has been reported to prevent declines in walking speed and maintain physical functioning (Hinman et al., 2023).

Stretching:

• A 2022 systematic review and meta-analysis article in Physiotherapy (Luan et al., 2022) found limited evidence to suggest stretching can be useful for pain management in individuals with knee OA

Different forms of exercise:

• there is a smaller evidence base for various other exercise types including yoga (20), and traditional Chinese exercise (21, 25) and different exercise forms should be considered based on patient preferences and treatment goals

Exercise parameters:

• a 2024 systematic review aimed to identify any link between number of resistance exercises prescribed in a program and outcomes but could not do so citing poor reporting of exercise regimens and low quality of studies included in their review as possible confounding factors (Lawford et al, 2025).

• exercise selection likely needs to be a patient specific shared decision. Lawford et al. (2025) discussed the complex multifactorial nature of improved pain and functional outcomes, with changes in other determinants such as self-efficacy, fear of movement, and pain beliefs likely mediating larger influences than changes in strength alone.

Cochrane

A 2024 Cochrane review (Lawford et al., 2024) included 139 trials looking at exercise therapy in OA as an intervention in isolation (versus placebo/ attention control), compared with usual care, and also alongside other interventions (such as diet and detailed education). They found low-to-moderate-certainty evidence that exercise probably results in improvements in pain, physical functioning and quality of life in the short term. There were potentially more benefits of combining exercise with other interventions. The review did caution that any changes may not meet the relevant thresholds to be considered clinically meaningful. Included studies varied widely in terms of duration and most of the included trials suffered an uncertain of high risk of bias.