OrthoLongevity™
Where we practise
The world's first Knee Age™ assessment — created by a consultant orthopaedic knee surgeon.
Designed for elite athletes. Now available to everyone.
Surgery · Sports Medicine · Physiotherapy · Strength & Conditioning · Nutrition · Sleep — one framework
PRIME is the five-domain assessment behind your Knee Age: Power, Risk, Injury, Movement, and Endocrine & Metabolic.
Strength and force capacity
Genetic and genomic risk
Injury and load history
Range, mechanics, posture and function
Hormones, metabolism and inflammation
PRIME measures. Knee Age scores. R.E.P.A.I.R.™ treats.
Knee Age™ weighs your answers across the five PRIME domains against published risk factors for joint ageing and the patterns seen in over 25 years of clinical practice. It is an educational estimate, not a diagnosis — and it improves as the evidence does.
Most people see a surgeon when the damage is already significant. Years of preventable deterioration have happened quietly — in the biology, the muscles, the metabolism — long before the pain becomes undeniable.
Home of the OrthoLongevity™ Longevity Movement Clinic. Performance laboratory, Biodex isokinetic strength testing, gait analysis, ultrasound-guided procedures, and surgeon-led assessment under one roof.
Register your email today and you will be first to access the full OrthoLongevity™ app and 12-week programme — before public launch, at early-access pricing.
In-depth articles written and reviewed by Dr Arj — honest, evidence-based guidance on treatments, surgery decisions, and keeping your knees for life.
Enter your email and receive your personal Knee Age assessment link — designed by a Consultant Orthopaedic Surgeon, free, in 60 seconds.
Early access subscribers hear about the full app and 12-week OrthoLongevity™ programme first.
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Your knee age is the biological age of your knees — which can be younger or older than the age on your passport. The Knee Age™ assessment scores you across five clinical domains in around 60 seconds and gives you a single number comparing your knees' biological age to your chronological age.
Probably not the same age as you. Cartilage health, muscle strength, movement quality, injury history and underlying biology all push knee age up or down. The free Knee Age™ test gives you an evidence-informed estimate in about a minute.
Yes. Knee Age™ is the world's first knee-specific biological age assessment, launched in 2025 and created by Dr Arj Imbuldeniya, a London consultant orthopaedic knee and hip surgeon. Heart Age changed how people think about their hearts; Knee Age™ does the same for your joints.
Knee Age™ focuses on the knee, the joint most likely to limit how you move and age. Many of the domains it measures — muscle strength, movement quality, metabolic health — affect every joint in your body, so your result is a strong signal for your wider joint health too.
No. It is an educational assessment, not a diagnosis, and it does not replace a consultation with a doctor. If you have knee pain, swelling, instability or an injury, seek a proper clinical assessment.
Nothing. The Knee Age™ test is free and takes around 60 seconds.
