A new study from China has some encouraging news about hydrotherapy and knee pain.
Researchers from a hospital in Neijiang, central China, recently examined 12 non-drug therapies to see how well they reduced pain and stiffness in patients with knee osteoarthritis. After trawling through 139 trials involving nearly 10,000 patients, they found that hydrotherapy was one of the most effective treatments – second only to knee braces overall.
“For the reduction of pain, this study demonstrates that aquatic therapy is particularly effective,” they concluded. “Aquatic therapy stands out in pain management, possibly due to the reduced impact and increased comfort of exercising in water compared to land.”
The good news is that water-based therapies – and pools – are becoming more and more available in clinics and hospitals around the UK. So how does hydrotherapy work – and who is it useful for?
What is hydrotherapy?
Hydrotherapy is the use of water in various forms – including warm baths, pools, and sometimes pressurised jets – to treat symptoms like muscle pain and joint stiffness, and often incorporating special exercises from a trained physiotherapist. You might also hear it called water therapy, aquatic therapy and occasionally balneotherapy.
What knee problems does it treat?
Hydrotherapy tends to be recommended for any kind of ongoing swelling, inflammation, bruising, stiffness and pain around the knee joint. Practically, that means things like managing osteoarthritis, relieving the symptoms of fibromyalgia (pain that’s widespread in the body) and for rehab after an injury or an operation – particularly following a knee replacement.
Why is hydrotherapy good for knee problems?
Good question! It has quite a few different benefits:
Temperature
Hydrotherapy pools are usually heated to around 33-36°C (91-97°F), which is warmer than the average swimming pool. The warmth is important because it dilates blood vessels, promotes blood flow, reduces swelling, and encourages the release of endorphins, helping your muscles to relax. By improving circulation, it also helps to clear the lactic acid that builds up after certain types of exercise.
Buoyancy
Water of course reduces gravity and supports weight – which means you can move much more freely than you would be able to on land, and with less pain. This opens up the kind of exercises that are vital for combatting stiffness and improving mobility – whether you’re struggling with arthritis pain or getting back on your feet after a knee replacement.
Coordination
The supportive qualities of water also improve balance and proprioception (the sense that tells your brain where your body is in space, enabling you to move and coordinate your actions). This is one of the reasons why hydrotherapy is often recommended for people with multiple sclerosis and cerebral palsy, or patients who are recovering after a stroke.
Resistance
While water supports mobility it also, paradoxically, provides low-impact resistance. Put simply: it takes more effort to move through water, which means you build up muscle strength – but gently. Strengthening your leg muscles is one of the surest ways to protect your knee health and alleviate pressure on a chronically damaged, swollen or painful joint.
Psychology
As the researchers indicated, being in warm water increases our “comfort”. That’s important too, because the way we think about pain is very closely related to how much pain we experience. Research has shown, for example, that our brains have the ability to tone down how intensely a harmful stimulus is experienced. Merely being in a hydrotherapy pool, in other words, may help people to feel more positive about their injury or pain – and their recovery.
How does a hydrotherapy session work?
Typically, your first hydrotherapy session would be a one-to-one appointment with a specialised aquatic physiotherapist. They’ll ask you about your knee, your medical history, and what you hope to get from the sessions. They’ll then guide you through a series of movements and exercises that are tailored to your knee situation. Hydrotherapy exercises tend to revolve around working with the water or against it (resistance training). Here are some examples:
Water walking – Walking across the pool in waist-high water, swinging your arms naturally and keeping your back straight and abdominal muscles tight
Deep-water walking – Walking in deeper water while swinging your arms and maintaining good posture, using a water noodle (a foam pipe) between your legs or a flotation device for buoyancy if needed
Leg exercise using a noodle – Tying a water noodle around one foot then, supported by the pool wall, repeatedly straightening and flexing the leg
You can read more about these and other exercises in this short guide: Aquatic exercises (Mayo Clinic). Bear in mind that you should always get advice from your doctor or physiotherapist on which exercises to use for your knee.
Length
Your first one-to-one session is likely to last 45 minutes; follow-up sessions are normally 30 minutes. Once you’ve completed your initial hydrotherapy programme, it’s usually possible to sign up for group “splash” sessions to carry on your rehab exercises.
Cost
Depending on where you go, a private hydrotherapy session with a physio is likely to cost between £60-£80 (2025 prices) for the initial assessment. Follow-up sessions are usually around £50-£60, or less for group sessions. If you’ve been signed off by your physio, you can sometimes book independent sessions for as little as £10 for 30 minutes (for instance at the Nuffield Wessex – see below).
Locations
You’ll find good hydrotherapy services right across the UK. Facilities that are popular with our own patients here in Hampshire include:
The Royal Hampshire County Hospital (Winchester) – for NHS referrals by your physio, your doctor or Mr Bailey
Wessex Nuffield Hospital (Chandler’s Ford) – for private physio-led sessions, which you can book on 0345 0454845
Pinder Aquatic Physiotherapy (Winchester Sport and Leisure Park) – for one-to-one private sessions with a physio and, potentially, independent exercise with the hydrotherapy pool and equipment: see their website for more details
Are you interested in finding out more about hydrotherapy for knee pain or as part of your rehab? Drop us a line and we’ll be happy to send you more details or arrange a consultation and referral with Mr Bailey.
