
Arthrosamid® Injection for
Knee Osteoarthritis
Harley Street, London | Led by Professor Paul Y.F. Lee
Arthrosamid® (a registered trademark of Contura A/S.).
Relief & Protect
The UK Authority in Arthrosamid®
Knee Injection
Arthrosamid® is a long-acting injection used to manage symptoms of knee osteoarthritis.
In London, Arthrosamid® treatment is led by Professor Paul Y.F. Lee, Consultant Orthopaedic Surgeon, medical engineer, and recognised UK authority in joint preservation and regenerative-aware knee care.
Professor Lee was the first clinician to perform Arthrosamid® knee injections in the UK and has developed a specialist, experience-led protocol based on large-volume clinical practice.


What Is Arthrosamid® (PAAG)?
Arthrosamid® is made from polyacrylamide hydrogel (PAAG) — a non-biodegradable, biocompatible material designed to remain inside the knee joint.
Unlike steroid or hyaluronic acid injections, Arthrosamid®:
- Is not absorbed by the body
- Remains in the joint long-term
- Acts as a mechanical cushion
- Symptom improvement lasting months
It does not regenerate cartilage and is not a cure for arthritis.
How Arthrosamid® Works
in the Knee
Inside the joint, Arthrosamid®:
- Improves joint lubrication
- Reduces mechanical stress on damaged cartilage
- Enhances shock absorption
- Helps reduce pain, stiffness, and functional limitation
It is best considered a joint-preserving treatment, helping patients remain active and delay more invasive surgery when appropriate.
Who Arthrosamid® Is
Best Suited For
Arthrosamid® is not a routine injection. Outcomes depend heavily on patient selection.
You may be a good candidate if:
You have mild to moderate knee osteoarthritis
You are middle-aged or older
You do not have diabetes
Both knees are symptomatic and being treated
You want improvement, not complete cure
Your goal is to delay knee replacement, not necessarily avoid it forever
We assess suitability using a structured PAAG-8+ patient selection framework, developed from clinical data and experience.




When Arthrosamid® May
Be Less Suitable
Arthrosamid® may be less effective if:
Your arthritis is advanced or bone-on-bone
The knee is severely unstable or deformed
You are already close to needing knee replacement
You expect a single injection to 'fix' the knee completely
Honest Clinical Advice
In these cases, benefit may be limited or temporary, and alternatives are discussed openly to ensure you receive the most appropriate care for your specific condition.
Independent Clinical
Study Experience
Our use of Arthrosamid® is informed by an independent, clinician-led clinical study, not sponsored by the manufacturer.

This allows us to give real-world, balanced advice, rather than relying on promotional claims.
Safety First: Why Our London Protocol Is Different
Professor Paul Y.F. Lee has now:
Personally performed
Arthrosamid® injections
Led a clinical group with
injections
Key safety principles include:

Intravenous (IV) antibiotics for every injection

No oral antibiotics (due to variable absorption)

Ultrasound-guided intra-articular placement

Enhanced sterile technique

A bespoke injection “cocktail”, developed internally
Some aspects of this protocol are intentionally not shared, as they form part of our internal safety practice.
Infection Risk &
Important Context
Infection is a risk with any joint injection.
With PAAG, infection is a particularly serious issue because the material is permanent.
Historical Complications in Literature:
There are published medical papers describing PAAG (often under the name Aquamid) complications, mainly relating to:
- Cosmetic soft-tissue injections
- Large volumes
- Non-joint use
These are not directly comparable to modern, image-guided knee injections, but they are important context and are discussed openly. Patients who wish to read this literature can be directed to the paper.

Clinical Longevity & Performance
Comparing Arthrosamid® with traditional knee injection protocols to help you make an informed clinical decision.
Arthrosamid®
Typical Duration
Up to 2 Years
Relief Type
Long-term
Key Considerations
- Non-biodegradable single injection
- Requires specialist safety protocols
PRP Therapy
BiologicalMixed clinical evidence regarding long-term efficacy.
Hyaluronic Acid
LubricationTemporary symptom relief, variable benefit.
Steroid Injection
Anti-inflammatoryShort-term acute relief only.
*Duration of efficacy varies by individual patient factors, severity of osteoarthritis, and clinical indications. Please consult with our medical team for a personalised assessment.


Arthrosamid® Treatment in Harley Street, London
Arthrosamid® injections are performed by Professor Paul Y.F. Lee at specialist clinics in Harley Street, London.
All patients undergo:
- Consultant-led assessment
- Imaging review (X-ray ± MRI)
- PAAG-8+ suitability assessment
- Shared decision-making discussion
Patients are referred nationally and internationally for Professor Lee’s experience in complex knee osteoarthritis and joint preservation.
Is Arthrosamid® Right for You?
Arthrosamid® can be an excellent option for the right patient, but it requires:
If these principles align with your goals, Arthrosamid® may be appropriate.


Book an Arthrosamid® Assessment – London
Long-lasting relief starts with the right decision — not just an injection.
Learn More about Arthrosamid
Deep dive into our clinical resources and patient guides.
Clinical Evidence
Evidence from Real Clinical Practice
Infection Safety
Infection Is a Serious Consideration With PAAG
Safety & Context
Arthrosamid Safety, Complications & Important Context
Full FAQ
Arthrosamid® (PAAG) Injection – Full Patient FAQ
Funding & Insurance
Funding, Insurance & NHS Coverage – Important Information
Patient Assessment
PAAG-8+ Questionnaire
Arthrosamid® (PAAG) Injection
Comprehensive Overview
Arthrosamid® is a registered trademark of Contura A/S. London Cartilage Clinic is not affiliated with or endorsed by Contura A/S.




