Percutaneous Hydrotomy for Knee Osteoarthritis: Treatment, Results and Evidence
How is percutaneous hydrotomy used for knee osteoarthritis? Explore decades of clinical experience, reported results in pain and function, cartilage and structural observations, and the current scientific evidence.
Percutaneous hydrotomy has been used clinically for several decades in the treatment of osteoarthritis and other musculoskeletal conditions. Practitioners using the technique have reported substantial improvements in pain, mobility and function, and structural changes have also been observed or reported in some patients on follow-up imaging.
At Centre Algos, we use percutaneous hydrotomy as part of our approach to knee osteoarthritis. Our clinical experience is consistent with the broader practitioner experience, with very good results observed in patients in terms of pain, mobility, function and return to activities that had become difficult because of their knee symptoms.
Knee osteoarthritis is a whole-joint condition, and no single treatment should be viewed in isolation. Hydrotomy can therefore be integrated with exercise, education, load management, weight management when relevant and appropriate medical treatment according to the person's wider clinical picture.
This article looks specifically at percutaneous hydrotomy for knee osteoarthritis: how the treatment works, the results observed in clinical practice, what has been reported regarding cartilage and joint structure, the clinical experience accumulated over several decades, and what the current scientific evidence tells us.
What is percutaneous hydrotomy?
Percutaneous hydrotomy is a local injection technique using multiple very superficial intradermal or subcutaneous injections.
This distinction is important: percutaneous hydrotomy is not the same as injecting a product directly into the knee joint.
The technique uses a saline-based solution that can act as a vehicle for substances selected according to the protocol and clinical situation.
At Centre Algos, the treatment is planned individually. The area treated, protocol, number of sessions and products used depend on the clinical presentation and safety assessment.
Why use percutaneous hydrotomy for knee osteoarthritis?
Knee osteoarthritis involves more than cartilage alone. Changes can affect the cartilage, subchondral bone, synovium, joint capsule and surrounding tissues, while pain and loss of function vary considerably from one person to another.
Percutaneous hydrotomy is used as a locoregional treatment around the affected anatomical area. Rather than injecting directly into the knee joint, the technique uses multiple superficial intradermal or subcutaneous injections according to the treatment protocol.
The clinical objective is not simply to change a radiological image. We look for meaningful improvements in pain, mobility, function and the person's ability to use the knee in everyday life. The structural changes reported in some patients on follow-up imaging are an additional and particularly interesting area of clinical observation.
Decades of accumulated clinical experience
Percutaneous hydrotomy was developed by Dr Bernard Guez and has been used clinically for several decades. The technique subsequently spread beyond his own practice and has been used by physicians and nurses in France and internationally.
Dr Guez's professional biography describes more than 350,000 interventional general-medicine treatment sessions across different conditions during almost 40 years of practice. This figure refers to treatment sessions across his interventional practice, not to 350,000 individual hydrotomy patients, but it illustrates the scale of the clinical environment in which the technique was developed.
The International Association of Percutaneous Hydrotomy reports that several thousand patients have been treated successfully with the technique and wished to continue treatment. The association has also collected formal patient attestations documenting diagnoses, previous treatments, clinical results and, where available, before-and-after CT or MRI findings.
Knee osteoarthritis has specifically formed part of the clinical development of the technique. University work includes a 2009 comparison of conventional mesotherapy and percutaneous hydrotomy in 20 cases of gonarthrosis, followed by further work examining large-dilution approaches for knee osteoarthritis. Hospital and practitioner experience has added to this accumulated clinical knowledge.
What results have been observed with percutaneous hydrotomy?
Clinical experience with percutaneous hydrotomy in knee osteoarthritis extends beyond Centre Algos. Practitioners using the technique have reported substantial improvements in pain, mobility and function in patients with knee osteoarthritis, including people whose symptoms had persisted despite previous treatment.
These clinical observations are one of the reasons percutaneous hydrotomy has continued to be used and developed in the treatment of osteoarthritis.
What results do we see at Centre Algos?
Our experience at Centre Algos is consistent with the broader clinical experience reported by practitioners using percutaneous hydrotomy.
We have seen very good results in patients with knee osteoarthritis, including substantial reductions in pain, improved mobility and function, and patients being able to return to activities that had become difficult because of their knee symptoms.
The response is assessed throughout treatment. Improvements in pain are important, but we also look at practical changes: walking, stairs, mobility, activity tolerance and the person's ability to return to the activities that matter to them.
In some cases, particularly interesting changes have also been seen on follow-up imaging. These observations contribute to the continued clinical interest in the potential structural effects of percutaneous hydrotomy.
Can cartilage improve or regenerate with percutaneous hydrotomy?
Cartilage and structural improvement are among the particularly interesting observations associated with percutaneous hydrotomy in osteoarthritis.
In clinical practice, changes have been reported or observed on follow-up imaging in patients treated for degenerative joint conditions, including findings suggesting improvement in cartilage or other joint structures. The International Association of Percutaneous Hydrotomy has also specifically collected patient documentation that can include before-and-after CT or MRI findings.
These observations are clinically important because they raise the possibility that the effects seen after treatment can extend beyond symptom relief alone. They are also one reason the potential regenerative effects of percutaneous hydrotomy remain an important area of clinical interest.
Formal controlled research has not yet established how consistently these structural changes occur, their magnitude or which patients are most likely to experience them. Larger studies using standardized imaging would help answer these questions.
The appropriate position is therefore to take the clinical and imaging observations seriously and investigate them further, rather than either treating cartilage regeneration as universally established or dismissing the observations because controlled imaging research is still developing.
What does the scientific evidence say?
What happens in knee osteoarthritis?
Osteoarthritis is a condition involving the whole joint, not simply the disappearance of cartilage.
Changes can involve:
articular cartilage
the bone beneath the cartilage
the synovium
the joint capsule
ligaments
muscles around the knee
the way forces are distributed through the joint
Some people have considerable structural osteoarthritis on imaging but relatively modest symptoms. Others experience substantial pain and limitation with less dramatic radiological changes.
This is why treatment should not be based on an X-ray alone.
The important questions are how much the knee hurts, what movements are limited, how the symptoms behave under load and how much they affect the person's life.
At Centre Algos, percutaneous hydrotomy is one of the treatments we use for knee osteoarthritis and can be integrated into an individual conservative treatment plan.
The starting point is the whole clinical picture rather than the X-ray alone.
Explanatory diagramHow a conservative knee osteoarthritis plan is built
Step 1: Knee osteoarthritis diagnosed or suspected
Step 2: Symptoms, function, previous treatment and goals assessed
Step 3: Individual treatment plan: percutaneous hydrotomy, exercise, education, load management, weight management when relevant and appropriate medical treatment
Step 4: Treatment response and function reassessed
Step 5: Plan adjusted according to progress, symptoms and goals
Percutaneous hydrotomy is one component of the plan, not an automatic step and not a last resort.
Hydrotomy therefore does not sit at the end of a sequence after every other conservative measure has failed. It is integrated alongside the other elements of the plan, and the plan itself remains individual.
How is it different from a cortisone injection?
The two procedures are fundamentally different.
An intra-articular corticosteroid injection places a corticosteroid medication directly into the joint.
Percutaneous hydrotomy uses superficial intradermal or subcutaneous administration around the relevant anatomical region rather than an injection into the joint space.
Corticosteroid injections have been investigated extensively in knee osteoarthritis. They can provide short-term symptom relief in selected patients, although the effect tends to diminish with time. A Swiss Federal Office of Public Health assessment found pain improvement at around one month but no meaningful improvement at three months compared with placebo or no treatment.
This does not make one procedure simply better than the other. They are different approaches with different evidence bases, indications and clinical considerations.
Does knee osteoarthritis always end in surgery?
No.
Knee replacement can be an effective treatment for advanced symptomatic osteoarthritis when pain and functional limitation remain unacceptable despite appropriate conservative treatment. But the presence of osteoarthritis does not automatically mean that joint replacement is required, and many people are managed non-surgically for long periods.
Whether a particular person eventually needs a knee replacement depends on factors including symptom severity, function, progression, overall health, response to treatment and personal preferences. We therefore do not present hydrotomy as a guaranteed way of preventing or permanently delaying a knee replacement. Its purpose is to improve the person's current pain, mobility and function as part of the treatment plan.
If symptoms and disability remain severe despite appropriate conservative care, orthopaedic assessment remains important.
What other treatment can be used alongside hydrotomy?
Hydrotomy sits alongside the other components of knee osteoarthritis care rather than replacing them. The osteoarthritis condition page gives the full overview; the essentials are summarised here.
Exercise. Individualised therapeutic exercise is one of the best-supported treatments for knee osteoarthritis, typically combining quadriceps, hip and lower-limb strengthening with aerobic work, mobility, balance where relevant and a gradual increase in walking or activity tolerance. Some discomfort at the beginning of a programme does not mean the joint is being damaged.
Activity and load management. Long periods of inactivity reduce strength and capacity. The aim is to find a manageable level of activity and build from there.
Weight management. For people living with overweight or obesity, weight reduction can improve pain and function. It is not relevant in the same way for every patient.
Medical treatment. Medication and other medical treatments are considered according to symptoms, medical history and contraindications. Centre Algos does not ask patients to stop prescribed medication; medication changes belong with the prescribing clinician.
Broader assessment where clinically relevant. Most people do not need extensive functional laboratory testing simply because they have osteoarthritis. It becomes useful when the picture also includes issues such as persistent fatigue, suspected nutritional deficiency, metabolic concerns or poor recovery. See Functional Biology & Micronutrition.
Who is hydrotomy for?
Hydrotomy can be used in patients with knee osteoarthritis when pain, reduced mobility or functional limitation form part of the clinical picture and the treatment is appropriate within the individual plan.
Relevant questions include:
Is the pain actually coming predominantly from the knee?
Does the clinical picture fit the known diagnosis?
How much does osteoarthritis limit walking, stairs or other activities?
What treatment is already taking place?
Is appropriate strengthening or rehabilitation part of the plan?
What treatment has already been tried, and how did the person respond?
Are there medical reasons why another intervention is or is not suitable?
What is the patient's objective?
Is further medical or orthopaedic assessment needed?
Having radiological osteoarthritis alone is not enough to answer these questions, which is why the assessment is individual.
When should knee pain be medically reassessed?
What happens during a consultation at Centre Algos?
We review:
your knee symptoms
how long they have been present
what activities are limited
existing X-rays, MRI or specialist reports
previous physiotherapy or exercise programmes
previous injections or procedures
medication
previous response to treatment
relevant medical conditions
your current activity level
what you want to be able to do again
We then discuss the treatment plan for your situation and whether percutaneous hydrotomy forms part of that plan. If it does, we explain the proposed approach before treatment begins.
Frequently asked questions
Is percutaneous hydrotomy a treatment for knee osteoarthritis?
Yes. At Centre Algos it is an established part of our approach to knee osteoarthritis and is integrated into an individual treatment plan alongside exercise, education, load management, weight management when relevant and appropriate medical treatment.
Is hydrotomy injected into the knee joint?
No. Percutaneous hydrotomy uses superficial intradermal or subcutaneous injections. It is different from an intra-articular knee injection.
Is it the same as a cortisone injection?
No. Corticosteroid knee injections are intra-articular and use corticosteroid medication. Percutaneous hydrotomy is a different technique with a different route of administration and evidence base.
Can cartilage improve with hydrotomy?
Structural changes, including findings on follow-up imaging suggesting improvement in cartilage or other joint structures, have been reported or observed in patients treated with percutaneous hydrotomy. These observations are one reason the potential structural effects of the technique remain an important area of clinical interest. How consistently they occur still needs to be established through larger studies using standardized imaging.
Can hydrotomy be used alongside exercise?
Yes. Hydrotomy is integrated alongside exercise, load management and the other relevant elements of treatment.
Can knee osteoarthritis be treated without surgery?
Often, yes. Many people are managed non-surgically for long periods. Surgery becomes relevant when symptoms and functional limitation justify it despite appropriate non-surgical care.
What evidence exists for hydrotomy in knee osteoarthritis?
Percutaneous hydrotomy has several decades of accumulated clinical experience, including university work specifically examining gonarthrosis, practitioner and hospital experience, and several thousand successfully treated patients reported by the professional association. Related large-dilution mesotherapy research provides additional clinical evidence, while the broader mesotherapy literature includes randomized controlled trials in musculoskeletal pain and knee osteoarthritis. The randomized mesotherapy studies are relevant to the broader locoregional approach but are not direct trials of percutaneous hydrotomy itself.
How do I know whether my knee pain is actually caused by osteoarthritis?
The diagnosis is based on symptoms, examination and, when appropriate, imaging. The severity seen on imaging does not always match the severity of pain.
Do I need a new MRI before hydrotomy?
Not automatically. Existing imaging may be sufficient, and some patients do not need MRI at all. Further imaging is useful when it answers a specific clinical question.
Can I continue physiotherapy while receiving hydrotomy?
In many situations, yes. Hydrotomy is incorporated alongside appropriate rehabilitation rather than replacing it.
What if hydrotomy does not help?
The response is reassessed throughout treatment, and the plan is adjusted if the expected clinical progress is not occurring.
When should I see an orthopaedic surgeon?
Orthopaedic review becomes especially relevant when pain and functional limitation are severe despite appropriate conservative care, when the diagnosis is uncertain or when surgical options need to be discussed.
Dr Bernard Guez, professional biography: source of the historical figure of more than 350,000 interventional general-medicine treatment sessions across different conditions during almost 40 years of practice (treatment sessions, not individual hydrotomy patients)
2022 multicentre study of large-dilution mesotherapy and mesoperfusion in 47 patients with chronic low back pain (related technique, not a randomized trial of percutaneous hydrotomy)
Still limited by knee osteoarthritis despite previous treatment?
At Centre Algos in Fribourg, we can review your symptoms, existing investigations and previous treatments and discuss how percutaneous hydrotomy and the other elements of your treatment plan fit your situation.
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