When a patient presents with knee osteoarthritis (OA), two of the most common self-management approaches recommended are to exercise and to lose weight.

In the current Osteoarthritis of the Knee Clinical Care Standard, quality statement 4 refers to weight loss and exercise, with recommendations that patients set weight and exercise goals.

While physiotherapists are qualified to develop exercise programs and give clients advice on incorporating more exercise into their lifestyle, providing advice on losing weight is not generally considered part of the job.

A recent study by researchers at the University of Melbourne, however, sees a role for physiotherapists in supporting weight loss in patients with knee OA.

‘Over the past five years, our research group has been looking at the potential role for physiotherapists in supporting people with osteoarthritis with overweight and obesity lose weight as per clinical guidelines alongside exercise.  

‘We’ve seen support in theory from both practitioners and patients with knee OA for physiotherapists to engage in a weight management role,’ says Kim Allison APAM, a researcher in the Centre for Health, Exercise and Sports Medicine at the University of Melbourne and part of a team, led by Professors Kim Bennell and Rana Hinman, looking at interventions for OA.

Previous studies by the research team had shown that a very-low-calorie diet delivered by dietitians along with an exercise intervention delivered by physiotherapists was superior to an exercise-only intervention across weight loss, pain and function outcomes (the Better Knee, Better Me trial, Bennell et al 2021).

Kim and her colleagues wanted to see if a similar result could be achieved with physiotherapists running both elements of the intervention.

Their qualitative studies had suggested that physiotherapists felt a responsibility to address weight and that focusing on exercise without considering weight loss only took the patients so far.

Furthermore, there were indications that patients felt that this would be acceptable coming from their physiotherapist.

But the studies also showed that many physiotherapists were uncomfortable and lacked confidence in bringing up the issue of weight loss with their patients.

So the team created an online training program to teach physiotherapists about weight management and attitudes towards obesity and evaluated it in a randomised controlled trial.

The trial compared two groups of physiotherapists (80 in total) randomly assigned to either the education group or a control group (Allison et al 2022).

The education arm received a self-directed online training program (EduWeight-OA) covering biosocial elements of obesity and weight management, which was co-developed by a group of endocrinologists, obesity researchers, tertiary education specialists, practising physiotherapists and dietitians with experience in weight loss interventions for OA.

The study was largely funded through a Physiotherapy Research Foundation Seeding Grant awarded in 2018, which covered both the development of the training program and the clinical study.

Kim Allison is researching the role of physios in dispensing weight management advice

The study showed that physiotherapists who completed the online training module demonstrated greater confidence in their knowledge of weight management as well as improved confidence in their nutrition care, clinical skills in weight management and understanding of weight stigma.

‘Those who went through the program felt more confident in their knowledge and their skills.

‘They found it valuable,’ says Kim.

Following the trial, Kim and her colleagues recruited some of the physiotherapists who completed the training program to take part in another.

The POWER trial used a similar protocol to that of the Better Knee, Better Me trial, but with a physiotherapist delivering the very-low calorie ketogenic dietary intervention combined with exercise for people with knee OA and overweight/obesity over a period of six months.

Another group received just the exercise component (Bennell et al 2022).

The results of the POWER trial are not yet published but they have been generally consistent with the previous study—participants in the cohort that received both an exercise program and a very-low-calorie diet lost a lot more weight than patients in the exercise-only arm.

As part of the POWER study, the research team has also interviewed a number of the patients allocated to the diet-plus-exercise arm to gain an understanding of the patient experience.

A similar qualitative study has looked at the perspective of the physiotherapists involved in the trial.

Both will form the basis of forthcoming research papers from the team.

‘Overall, the physiotherapists felt confident about how they delivered the program and they felt they were perceived as credible by the patients.

‘But some of the physios found it difficult, especially when dealing with the more intense side effects of a low-calorie ketogenic diet. It made them a bit nervous,’ Kim says.

She notes that over the course of the trial, as the physiotherapists became familiar with the effects of a low-calorie ketogenic diet, they gained confidence.

In addition, the trial physiotherapists were well supported by the dietitians, who developed the low-calorie ketogenic diet program used in the trial.

Kim is not advocating that all physiotherapists should be handing out dietary advice to their patients.

‘We’re not dietitians and we don’t all have a nutrition background.

‘It’s really just health behaviour change support for someone who might choose this option.

‘One of our team members calls it coaching and that’s exactly what it is.

‘People can choose what they want to do and access all the information they need—there’s nothing they are going to get from a physio that they couldn’t access freely online or in a book.

‘But we physios typically have strong relationships with our patients and it can be a safe space to get support,’ Kim says.

One of the issues with physiotherapists dispensing weight management advice without some form of training is the risk of giving dietary advice that is not backed up by the latest evidence.

‘It’s about providing the support and training for physios so that they’re not inadvertently providing misguided information based on their own choices and experience,’ Kim says.

Overall, however, she believes that there is a role for physiotherapists in providing health behaviour change support for lifestyle weight loss interventions, to patients where weight loss is relevant in their care.

‘When we think about it pragmatically, obviously not all physios are going to deliver weight loss interventions for osteoarthritis; that’s not going to happen.

‘But when you think about the pinch points in our healthcare system—like rural and remote delivery, where we don’t have access to a lot of expert practitioners per se—that’s probably where this comes in a bit more,’ Kim says.

Kim says there are two directions she’d like to take the research in the future.

One aspect she wants to look at is the logistical barriers to incorporating weight loss advice and support into a physiotherapy practice—whether public or private—such as professional indemnity issues, for example.

She’d also like to develop a comprehensive online support program for people with knee OA based on the information given to patients in the POWER trial, including information on the low-calorie ketogenic diet, recipes and motivational tools as well as patient education about OA, the role of exercise and patient beliefs.

In the meantime, the EduWeight-OA training program is available to physiotherapists who want to improve their understanding of and ability to support patients with chronic disease impacted by overweight or obesity.

Since the trial, 2348 physiotherapists have completed the program, pointing to an appetite for better understanding of weight management among physiotherapists.

>>The EduWeight online training program for physios is available here.

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