Misconceptions and the acceptance of evidence-based nonsurgical interventions for knee osteoarthritis. A qualitative study

The short answer

Why do patients with knee osteoarthritis often reject evidence-based nonsurgical treatments like exercise and physiotherapy?

Patients awaiting knee replacement commonly hold misconceptions, such as believing their joint is irreparably 'bone on bone' and that exercise will cause further damage, which leads them to reject effective nonsurgical care in favour of surgery or unproven treatments. Addressing these beliefs during clinical consultations may be a key step toward improving uptake of exercise and weight loss interventions.

DescriptiveRead paper

Primary study27 ParticipantsLimited evidence

Key points

All 27 participants described their knee as 'bone on bone' and believed bone rubbing was the direct cause of their pain.
Most participants believed that loading the knee through exercise would cause further joint damage, contradicting evidence that loading exercise is safe and beneficial.
Many participants preferred experimental cartilage-regeneration treatments or surgery over physiotherapy, believing nonsurgical options could not replace lost cartilage.
All participants believed their knee OA would only worsen over time, creating urgency to seek surgical rather than conservative care.
Clinician language, such as the phrase 'bone on bone', appeared to reinforce unhelpful beliefs and reduce acceptance of nonsurgical options.

The bigger picture

In an Australian community setting, 50% of people with knee OA had never participated in an exercise intervention, and 38% had never attempted weight loss despite being overweight.

Bunzli et al. (2019), citing Australian community-setting data

In the Australian primary care setting, general practitioners referred patients with knee OA for surgical opinion 12% of the time, compared with less than 4% for a nonsurgical intervention.

Bunzli et al. (2019), citing Australian primary care data

Among patients on an orthopaedic waiting list at a metropolitan tertiary hospital in Australia, 39% had not previously engaged in nonpharmacological, nonsurgical intervention.

Bunzli et al. (2019), citing prior Australian hospital data

The average cost of a TKA in Australia is AUD 21,000, and the total annual cost of TKA in Australia is AUD 1.3 billion.

Bunzli et al. (2019), citing Australian costing data

How it was conducted

Design: Cross-sectional qualitative study using one-to-one semi-structured interviews and Framework Analysis
Setting: Single tertiary orthopaedic hospital, metropolitan Australia
Participants: 27 adults (48% women, mean age 68 years, mean BMI 33 kg/m2) on the waiting list for total knee arthroplasty (TKA)
Data collection: Audio-recorded interviews averaging 30 minutes; 7 face-to-face and 20 telephone
Analytical framework: Five belief dimensions based on the Common Sense Model: identity, cause, consequences, timeline, and treatment beliefs
Recruitment period: March to September 2018; recruitment stopped when thematic saturation was reached

What they found

All 27 participants described their knee OA as 'bone on bone' and attributed their pain to rubbing of bare bone surfaces (identity beliefs: all participants).
Most participants (more than 14) believed their knee OA was caused by wear and tear from excessive loading or physical activity (causal beliefs).
Most participants (more than 14) believed that loading the knee would further damage their vulnerable, cartilage-free joint and adopted movement-avoidance behaviours (consequence beliefs).
All participants believed their knee OA symptoms would worsen over time and that bone loss was inevitable (timeline beliefs).
Many participants (more than 20) believed physiotherapy and exercise could not help 'bone on bone' changes and had stopped or avoided these interventions as a result (treatment beliefs).
Many participants (more than 20) had sought or expressed preference for experimental cartilage-regenerating injections or supplements over physiotherapy.
Only a few participants were currently engaged in an exercise intervention at the time of interview; the most common was hydrotherapy.
48% of participants had already undergone a contralateral TKA, suggesting prior surgical experience reinforced surgical preference.

Limitations

Single-site recruitment from one orthopaedic service in Australia limits generalisability; beliefs may reflect the communication style of that specific surgical team.
Small, non-random sample of 27 English-speaking participants excludes people from non-English-speaking backgrounds, whose beliefs may differ.
Reliance on participant recall of previous nonsurgical interventions rather than medical record review may have led to incomplete or inaccurate reporting.
Selection of patients already on the TKA waiting list means only those who had reached the surgical stage were interviewed; beliefs of patients in earlier disease stages were not captured.

Why it matters

For patients: Patients who have been told their knee is 'bone on bone' should know that exercise and physiotherapy are safe and effective even at that stage and are not likely to cause further damage.
For clinicians: Surgeons and physiotherapists should actively explore and correct patient misconceptions about knee OA identity, cause, and treatment, and should be mindful that language like 'bone on bone' can inadvertently discourage beneficial nonsurgical care.
For readers: This study provides a patient-perspective explanation for the well-documented underuse of nonsurgical knee OA treatments, pointing to modifiable belief patterns as a target for future interventions.

Source

doi:10.1097/corr.0000000000000784

Read the original paper

Clinically assessing this area? See the knee special tests.