Arthrosamid® Injection
Full Patient FAQ

Arthrosamid® at London Cartilage Clinic costs from £3,000 for one box, £5,500 for two boxes, or £8,000 for three boxes, including the items stated in the current package. See the full Arthrosamid® cost guide for what is and is not included.

No. Arthrosamid® is not routinely funded by the NHS. Patients access treatment privately on a self-funded basis. Full detail on the Arthrosamid® funding and insurance page.

Cover depends on the policy, coding and written pre-authorisation in force at the time. London Cartilage Clinic is a private-pay practice; it can supply an itemised invoice, but reimbursement is decided by the insurer. Obtain a written decision before booking.

Headline prices differ because what is included differs. A cheaper quote often excludes IV antibiotic cover, MRI imaging, clinical follow-up or the ultrasound-guidance and protocol used at higher-cost clinics. See the Arthrosamid® cost guide for the questions to ask before comparing prices.

Most patients settle by bank transfer or card before the procedure. We can discuss finance options on request rather than promoting a specific finance partner. Ask the team during your free discovery call if monthly payment is a consideration.

The prospective observational cohort reported exploratory subgroup associations. These do not form an individual responder rule. Assessment may consider whether:

• Symptoms, function and goals are consistent with non-surgical symptom management
• Imaging and examination have been reviewed rather than the X-ray label being used alone
• Infection risk, allergies, medicines and contraindications have been assessed
• Alternatives, including rehabilitation and surgical assessment, have been discussed
• You understand that response and duration cannot be predicted or guaranteed

We assess this using a structured Arthrosamid® suitability framework.

Arthrosamid® may be less suitable if:

• You have advanced end-stage arthritis
• The knee is severely unstable or deformed
• You are already close to needing knee replacement
• You expect the injection to fully cure your knee

These situations need individual assessment; the published evidence cannot reliably predict benefit for a particular person.

Sometimes yes, sometimes no. Where knee replacement is the clinically appropriate answer, Arthrosamid® is not a substitute. Where surgery has been suggested but you want to explore a non-surgical symptom-management option, Arthrosamid may be discussed. It has not been proved to delay surgery. Imaging, examination, function and goals determine whether a replacement opinion is more appropriate.

A “bone-on-bone” label does not by itself predict whether Arthrosamid® will help. Imaging, pain, function, alignment, stability and goals need to be considered together. Where knee replacement is clinically more appropriate, the injection should not be presented as a substitute or a way to delay surgery.

Start with the Arthrosamid® suitability self-assessment — eight questions, around three minutes. It is a discussion aid, not a diagnostic or predictive tool. Clinical assessment and imaging are required before any suitability decision.

The prospective observational cohort reports group outcomes through 24 months. That is a defined follow-up period, not a guaranteed response or duration for an individual.

Improvement is not necessarily immediate and may develop over the following weeks. The clinic reviews the early response at around six weeks. A temporary flare can occur, but worsening pain, heat, redness or swelling with systemic symptoms needs prompt advice.

No. A minority of patients do not get the expected level of relief. That is one reason suitability assessment matters before treatment — we would rather decline a case than treat someone whose chance of meaningful benefit is low.

If symptoms have not improved by twelve weeks we re-review imaging and clinical findings, discuss whether a further box would be appropriate, and consider alternative pathways. Where end-stage arthritis is the underlying issue, knee replacement may be the better answer; we will say so honestly. Read more on the Arthrosamid® clinical evidence page.

The primary London Cartilage Clinic/MSK Doctors paper reports a prospective observational cohort. It has no randomised control group; funding and declarations should be read in the paper itself.

• 269 patients
• 314 knees treated
• Prospective follow-up
• Up to 24 months
• Pain, function, complications, and progression to knee replacement recorded

The study is useful real-world evidence, but its design cannot establish causation or predict an individual result.

Ultrasound guidance, sterile technique, antibiotic cover and selection support safe care but do not eliminate risk. Joint infection is a serious potential complication. See the dedicated side effects and safety and infection risk pages for the full picture.

Temporary injection-site pain, swelling, warmth or stiffness can occur after treatment. Worsening pain, increasing heat or redness, fever, discharge or feeling systemically unwell requires prompt clinical advice rather than being assumed to be a routine flare.

Infection is a risk with any joint injection. Arthrosamid is non-absorbable and intended to remain in the joint, which can make a serious complication difficult to manage.

If infection occurs:

• It may be harder to eradicate
• Treatment may be prolonged
• Surgical intervention may occasionally be required

This is why our protocol places exceptional emphasis on infection prevention.

Manufacturer professional information requires prophylactic antibiotic cover. London Cartilage Clinic's documented local protocol uses intravenous antibiotics after allergy, interaction and medical-history checks.

• All Arthrosamid® injections are performed with IV antibiotics
• Sterile-field preparation and written warning-sign advice are part of the pathway

Our clinic does not recommend oral antibiotics for Arthrosamid® injections because:

• Oral absorption is variable
• Joint concentrations are unpredictable
• Timing around injection is less reliable
• Effectiveness against biofilm-forming bacteria may be reduced

London Cartilage Clinic uses intravenous cover as a local protocol. It supports prophylaxis but cannot eliminate infection risk, and the treating clinician must check whether it is safe for the individual.

Yes.

As part of Professor Lee’s specialist protocol, Arthrosamid® injections include a bespoke injection “protocol”, used alongside the hydrogel.

This has been developed and refined based on:

• Scientific principles
• Clinical assessment and documented protocol review
• Ongoing review of outcomes and complications

This pathway is intended to reduce avoidable risk; the site does not claim that an unpublished clinic comparison proves a lower complication rate.

The exact composition and method form part of our internal protocol and are not shared externally.

This protocol reflects:

• Manufacturer professional information and product precautions
• Sterile-field, antibiotic, imaging and aftercare checks
• Clinical audit without using unsupported activity totals as outcome evidence

Patients should receive enough information to understand the purpose, medicines, alternatives and material risks, while operational sterile-field details remain part of the clinic's protocol.

Manufacturer professional information requires prophylactic antibiotic cover. The choice of medicine, route and timing is a clinical decision subject to allergy, interaction and medical-history checks.

London Cartilage Clinic's documented local pathway uses intravenous cover, ultrasound guidance, sterile-field preparation and written aftercare. This describes London Cartilage Clinic's process without speculating about other clinics or claiming that it eliminates risk.

Aquamid and Arthrosamid® are both polyacrylamide hydrogel products.

There are published papers describing hydrogel complications, mainly involving:

• Cosmetic or soft-tissue injections
• Large volumes
• Non-joint tissues
• Long-term delayed presentations

These are not directly comparable to modern, image-guided knee injections — but they are important context, and we encourage informed patients to read the literature if they wish.

It means:

• Arthrosamid® is treated as a specialist procedure, not a routine injection
• Safety is prioritised over convenience
• Decisions are based on experience, science, and outcomes
• If you are uncomfortable with IV antibiotics or a bespoke protocol, Arthrosamid® may not be the right option

Manufacturer professional information requires prophylactic antibiotic cover. London Cartilage Clinic's local protocol uses an intravenous route; that distinction should be described accurately rather than as a claim that product guidance is ignored.

The local protocol adds operational detail around the manufacturer requirement because:

• Arthrosamid® is non-biodegradable
• Complications, if they occur, can be more complex
• Published clinical literature shows that context and technique matter
• Long-term outcomes depend on more than the product alone

For these reasons, Professor Paul YF Lee developed a protocol based on:

• Direct clinical experience
• Published evidence and clinical audit
• Conservative risk management and audit data
• Continuous refinement over time

This includes:

• Mandatory IV antibiotics
• Enhanced sterile technique
• A bespoke injection protocol
• Structured follow-up

Arthrosamid® is a non-absorbable injection intended to manage symptoms of knee osteoarthritis in adults.

It is made from a polyacrylamide hydrogel, a non-biodegradable material intended to remain inside the knee joint. Its proposed action is mechanical cushioning and lubrication.

Most injections are absorbed over weeks or months.

Arthrosamid®:

• Is not absorbed
• Remains in the joint long-term
• Has observational group-level outcomes reported through 24 months

Because it is non-absorbable and intended to remain in the joint, product-specific selection, infection precautions and informed consent are required.

No.

Arthrosamid® does not regenerate cartilage and is not a Stem Cell / Medicinal Signaling Cell treatment.

It helps by:

• Improving joint lubrication
• Reducing mechanical stress
• Aiming to improve symptoms; group-level pain and function changes are reported in the observational cohort

It is intended for symptom management, not as a cure or disease-modifying treatment.

Different goals. Steroid injections are commonly considered for shorter-term symptom control. Arthrosamid® is a non-absorbable hydrogel with observational outcomes reported to 24 months. The treatments have different roles and evidence; neither offers a duration guarantee or should be assumed to delay surgery.

Hyaluronic acid is resorbable and treatment may be repeated; the response and duration vary. Arthrosamid® is a non-resorbable polyacrylamide hydrogel administered as a single 6 ml knee injection. Evidence, risks, previous treatment and patient priorities should guide the choice; comparative evidence does not justify describing either as automatically superior.

Different mechanisms and different evidence quality. PRP is an autologous biologic; in knee OA preparation methods and results vary. Arthrosamid® is a non-resorbable hydrogel with observational outcomes reported to 24 months. Comparative evidence and individual priorities matter; neither should be presented as automatically better.

Arthrosamid has not been proved to delay or prevent knee replacement. It may be discussed as symptom management, but it is not a substitute for surgery where replacement is clinically appropriate and it does not regenerate cartilage.

The primary cohort was clinician-led, but its funding and conflict declarations should be read in the publication. “Independent” should not be used as a blanket label without checking the paper's own declarations.

This helps ensure that the information used to guide your treatment reflects real clinical experience, rather than marketing claims.

Use the funding and conflict declaration in the specific publication.

This allows outcomes to be discussed openly — including:

• Patients who improve
• Patients who notice limited benefit
• Patients who later progress to knee replacement

Yes — in a positive way.

Regardless of a study's funding declaration:

• Arthrosamid® is not offered routinely
• It is recommended only after indication, contraindications and alternatives are assessed
• Other options are discussed honestly when appropriate

If Arthrosamid® is unlikely to provide meaningful benefit, we will say so.

Yes.

Observational studies can describe outcomes in everyday practice, but without randomisation and a control group they cannot establish causation as securely as a well-designed comparative trial.

This helps patients understand:

• The distribution of outcomes during the observed follow-up period
• Exploratory subgroup associations that need cautious interpretation
• When alternative treatments may be more appropriate

It means your treatment plan is based on:

• Balanced clinical experience
• Clear discussion of benefits and limitations
• Realistic expectations

Transparent methods, declarations and limitations support better decisions.