Arthrosamid Injection

Knee Pain From Running: Causes, Treatment, and When to Consider an Arthrosamid Injection

1 June 2026

10 min read

Active adult resting after a run with knee pain, considering treatment options including Arthrosamid injection for knee osteoarthritis

Running does extraordinary things for your health. It strengthens the heart, clears the mind, and builds genuine resilience. But it also places enormous repetitive stress on one particular joint — the knee. And when the knee starts to complain, it can stop even the most committed runner in their tracks.

Knee pain from running is one of the most common reasons people reduce or stop exercise altogether. Understanding what is actually happening inside the joint — and knowing what your options are — makes all the difference between a temporary setback and a long-term problem.

This guide covers the most common types of running knee injuries, what causes them, how to treat them, and when a more advanced intervention such as an Arthrosamid injection may be worth exploring.

Why Does Running Cause Knee Pain?

The knee is the largest joint in the body. With every stride you take, it absorbs a force roughly two to three times your body weight. Over the course of a 5K run, that adds up to thousands of repetitive impacts. Over years of running, the cumulative effect on the joint’s cartilage, tendons, and soft tissue can be significant.

Running does not damage healthy knees — but it does expose any existing weaknesses, imbalances, or structural vulnerabilities.

The most common reasons runners develop knee pain include:

Overuse — increasing mileage or intensity too quickly
Poor running form or biomechanical issues
Weak quadriceps or hip muscles that fail to protect the knee joint
Worn or unsuitable footwear
Running on hard surfaces without adequate recovery
Existing cartilage wear that the body was quietly managing until the load increased

The Most Common Types of Knee Pain From Running

1. Runner’s Knee (Patellofemoral Pain Syndrome)

Runner’s knee is the most common running-related knee complaint. It causes pain around or behind the kneecap — often described as dull and persistent, though it can become sharp with activity.

It tends to worsen when you run downhill, climb stairs, or sit with your knees bent for a long period. The cause is usually an imbalance in the muscles that track the kneecap, combined with the repetitive loading of running. Treatment: Rest, targeted physiotherapy to strengthen the quadriceps and hip stabilisers, and a temporary reduction in mileage. Most cases resolve with consistent rehabilitation.

2. Iliotibial Band Syndrome (IT Band Syndrome)

The iliotibial band is a thick strip of connective tissue that runs from the hip to the outer side of the knee. In runners, it can become tight and inflamed where it crosses the knee joint.

The hallmark symptom is a sharp or burning pain on the outer side of the knee, typically appearing after a set distance into a run. It often disappears at rest and returns predictably on the next run.

Treatment: IT band stretching, foam rolling, and hip strengthening exercises. Running gait analysis can identify the biomechanical factors driving the problem.

3. Patellar Tendinopathy (Jumper’s Knee)

Despite being called jumper’s knee, this condition affects runners who repeatedly load the patellar tendon — the structure connecting the kneecap to the shin bone. Overuse causes the tendon to become irritated and degenerate over time.

Pain is typically felt just below the kneecap and is often worst when you start a run, eases mid-run, and then worsens again afterwards. Treatment: Load management, progressive tendon-loading exercises, and in some cases, physiotherapy-guided rehabilitation over several months. Recovery takes patience.

4. Meniscal Irritation or Tears

The menisci are two cartilage discs inside the knee that act as shock absorbers. Sudden twisting movements — particularly when the foot is planted — can cause tears. In older runners, gradual degeneration can cause the same result without any obvious injury.

Pain on the inner or outer side of the knee, swelling, and a sensation of the knee catching or locking are all potential signs of meniscal damage.

Treatment: Minor tears often settle with rest and physiotherapy. Significant tears may require arthroscopic surgery.

5. Knee Osteoarthritis — The Longer-Term Picture

This one deserves particular attention. Knee osteoarthritis is not typically caused by running — but running on a knee that already has some cartilage wear can accelerate symptoms and bring underlying osteoarthritis to the surface.

Osteoarthritis develops when the cartilage that cushions the knee joint gradually wears away, leading to pain, stiffness, and reduced mobility. It is especially common in people over 50 and affects women disproportionately due to hormonal changes after the menopause, differences in anatomy, and lower average quadriceps strength.If your knee pain from running is accompanied by morning stiffness, swelling, creaking, and difficulty on stairs — and it is not settling with rest — it is worth having the joint properly assessed. The underlying cause may be osteoarthritis rather than a simple overuse injury.

How to Treat Knee Pain From Running

Start With Self-Management

For most acute running injuries, the first approach is conservative:

Stop running and rest the knee — continuing to run through significant pain causes further damage
Apply ice wrapped in a cloth for 15 to 20 minutes several times a day during the first 48 to 72 hours
Take paracetamol for pain relief — this is the first-line recommendation from NICE for musculoskeletal pain. Topical NSAIDs such as diclofenac gel can help with localised inflammation
Elevate the leg when resting to reduce swelling
Switch to low-impact exercise such as swimming or cycling to maintain fitness while the knee recovers

When to See a Doctor or Physiotherapist

Do not ignore knee pain that persists for more than a week without improvement. Seek medical attention sooner if:

The knee is significantly swollen
The pain is severe or sudden
The knee gives way or feels unstable
You hear or feel a popping sensation at the time of injury

A GP or physiotherapist can assess the knee, arrange imaging if needed, and guide your rehabilitation. Getting the diagnosis right is essential — treating IT band syndrome and osteoarthritis with the same approach will not work.

Physiotherapy

Physiotherapy is the cornerstone of recovery for most running knee injuries. A good physiotherapist identifies the underlying cause — whether that is muscle weakness, poor movement patterns, or biomechanical issues — and builds a structured programme to address it.

Do not underestimate physiotherapy. Many runners return to full training after a proper course of rehabilitation without needing any further intervention.

When Knee Pain From Running Points to Something More Serious

Sometimes, knee pain from running does not resolve with rest and physiotherapy. This is particularly true when:

The underlying joint has sustained cartilage damage or early-stage osteoarthritis
Steroid injections have provided only temporary relief
The pain returns consistently whenever running resumes
The quality of daily life — not just running — is being affected

This is when a more targeted intervention becomes worth considering. For suitable patients with mild to moderate knee osteoarthritis, an Arthrosamid injection represents a clinically meaningful option.

What Is an Arthrosamid Injection and How Can It Help?

An Arthrosamid injection is a single, ultrasound-guided injection of a non-biodegradable hydrogel directly into the knee joint. It is made of 97.5% water and 2.5% cross-linked polyacrylamide. Once inside the joint, the hydrogel gradually integrates with the synovial membrane — the soft lining of the knee — over four to six weeks.

This integration may help to reduce inflammation, improve joint cushioning, and restore some of the elasticity the joint has lost as osteoarthritis has progressed.

It is not a cure for osteoarthritis. The arthritis remains. But for the right patient, an Arthrosamid injection can reduce the chronic background pain that makes running — and everyday activity — so difficult.

What the Evidence Shows

Published clinical studies report sustained improvements in pain and function for up to five years following a single Arthrosamid injection in suitable patients. A 2025 five-year follow-up study showed continued meaningful improvements in that timeframe.

For runners who have been managing persistent knee pain and are not yet ready for knee replacement surgery, that kind of sustained relief from a single, minimally invasive procedure is significant.

How Is Arthrosamid Different From a Steroid Injection?

A steroid injection reduces inflammation temporarily — typically for a few weeks to a few months. It does not address the structural problem in the joint, and repeated steroid use can damage cartilage over time.

An Arthrosamid injection works differently. It integrates with the joint tissue and may provide longer-lasting support without the risks associated with repeat steroid injections.

Who Is Suitable for an Arthrosamid Injection?

Arthrosamid tends to be most appropriate for patients who:

Have mild to moderate knee osteoarthritis confirmed on imaging
Have already tried physiotherapy, pain relief, and lifestyle modifications
Are not ready for — or wish to avoid — knee replacement surgery
Continue to experience meaningful pain that limits activity

It is not suitable for patients with active joint infection, very advanced bone-on-bone arthritis, or allergy to polyacrylamide. The only way to confirm suitability is a proper clinical assessment.

Running After an Arthrosamid Injection — What to Expect

Most patients can return to light daily activity within a few days of the injection. Walking is encouraged. Heavy impact — including running — should be avoided for the first few weeks.

The improvement tends to build gradually. Most patients notice meaningful changes in pain and stiffness between weeks eight and twelve, as the hydrogel becomes fully integrated with the synovial tissue.

Whether a return to running is realistic will depend entirely on the individual patient — the degree of osteoarthritis, the response to treatment, and the guidance of the treating clinician. Mr Abbas gives every patient personalised aftercare advice at their follow-up assessment.

Preventing Knee Pain From Running: Practical Steps

Prevention is always preferable to treatment. If you currently run without knee pain and want to keep it that way:

Build mileage gradually — the 10% rule (increasing your weekly distance by no more than 10% at a time) remains a sensible guide
Invest in proper running shoes fitted to your gait at a specialist running shop
Strengthen your supporting muscles — particularly your quadriceps, hamstrings, and glutes. Strong muscles protect the knee
Warm up before every run with five to ten minutes of brisk walking or gentle movement
Mix surfaces — running exclusively on hard pavements increases cumulative joint stress
Listen to your body — persistent discomfort is a signal, not something to train through

Key Takeaways

Knee pain from running is extremely common and has many possible causes — correct diagnosis matters
Most acute injuries respond well to rest, physiotherapy, and a structured return to running
If your knee pain is persistent, worsening, or accompanied by stiffness and swelling, seek a clinical assessment — osteoarthritis may be the underlying cause
For suitable patients with knee osteoarthritis, an Arthrosamid injection offers a non-surgical option with evidence of sustained pain relief for up to five years
The right treatment depends entirely on what is actually causing the pain. Get it assessed properly before you do anything else.

If you are concerned about persistent knee pain from running, Mr S N Abbas offers private knee consultations at 48 Wimpole Street, Marylebone, London. The initial consultation costs £100, fully redeemable against treatment. Call or book online to discuss your options.

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