Knee osteoarthritis: relieving the pain between injections and movement

Does your knee hurt going up stairs, getting up from a chair, or even at night? Knee osteoarthritis — or gonarthrosis — affects nearly one in three French people after 60. The good news: between injections that calm and movement that repairs, you have real cards to play to get back to an active life without pain.

What is knee osteoarthritis exactly?

The knee is a complex joint that bears your entire body weight at every step. Between the femur, tibia and kneecap, a protective cartilage cushions the shocks. Over time, with trauma or prolonged excess weight, this cartilage wears down and crumbles. The result: the bones rub against each other, the joint becomes inflamed and pain appears.

Gonarthrosis typically shows up as morning stiffness, pain when going up and down stairs, joint cracking and sometimes a knee that swells after exercise. But — and this is essential — pain does not mean immobility. The same logic applies to all joints: see our article Exercise and osteoarthritis: moving without pain.

Injections: real but temporary relief

When pain becomes disabling, your rheumatologist may offer an injection. Three types exist today:

• Corticosteroids: powerful anti-inflammatory action, quick relief within 2 to 5 days. Average effectiveness of 6 to 12 weeks. Limited to 2 or 3 per year to preserve cartilage.
• Hyaluronic acid (viscosupplementation): acts as a joint lubricant. Slower to take effect (3 to 4 weeks) but can last 6 months to a year.
• PRP (platelet-rich plasma): uses your own growth factors to stimulate regeneration. Newer technique, variable results depending on the patient.

“The injection calms the fire. Movement changes the ground. The two are complementary, never opposed.”

Injections are an excellent therapeutic window: they reduce pain, which allows you to move again. But without muscle and joint work in parallel, their effect always fades. Movement is what acts on the cause.

Why movement is your best long-term treatment

Cartilage has no blood vessels. It is fed exclusively by movement, which pumps synovial fluid through each compression-decompression cycle. Without physical activity, cartilage dries out and degeneration accelerates.

Moreover, around your knee, the quadriceps and hamstrings act as natural shock absorbers. The stronger they are, the less pressure the joint takes with each step. Strengthening these muscles means giving your knee a true muscular brace.

Several studies published in Annals of Internal Medicine and The Lancet Rheumatology have confirmed that adapted physical activity reduces osteoarthritis pain as effectively as anti-inflammatory drugs, without any side effects.

Exercises to prioritise for knee relief

Not all exercises are equal for an arthritic knee. Here are the ones that have proven themselves:

• Cycling (stationary or outdoor): takes the body weight off while mobilising the joint. Ideal as a first approach. Start with 10 minutes, increase gradually.
• Walking on flat ground: 30 minutes a day, at a comfortable pace. Avoid very uneven paths at first.
• Swimming and water aerobics: water removes 90% of your weight. Perfect for mobilising without straining.
• Quadriceps strengthening: the flagship exercise is the seated leg extension, 3 sets of 10 reps, 3 times a week.
• Gentle stretching: hamstrings, calves and hips to preserve mobility of the whole muscular chain.
• Tai chi and gentle yoga: excellent for proprioception and balance, two elements often lost with osteoarthritis.

Gestures to avoid so you don't make it worse

Some activities place too much stress on the arthritic knee and can accelerate degradation:

• Running on hard roads without prior muscle preparation
• Sports with violent direction changes (tennis, squash, football)
• Deep squats that bend the knee beyond 90°
• Carrying heavy loads going down stairs
• Prolonged immobility — paradoxically the worst for the joint

The classic mistake is to stop everything because of pain. Total rest accelerates stiffness and muscle loss. The right approach is to adapt, not eliminate. For a gradual return after a period of inactivity or a flare, see our guide Resuming sport after an injury.

Combining injections and exercise: the winning strategy

The best therapeutic approach combines both logics. Here is the protocol we see working best for our clients:

• Phase 1 — Targeted injection: to break the inflammatory cycle and reduce baseline pain.
• Phase 2 — Gradual return to movement as soon as the pain drops (generally 1 to 2 weeks after the injection). This is the ideal therapeutic window.
• Phase 3 — Structured muscle strengthening programme, 2 to 3 sessions per week for at least 8 to 12 weeks.
• Phase 4 — Maintenance: 2 sessions per week to keep the gains, for life.

Without this movement phase, the injection only pushes the problem back. With it, it becomes a real springboard towards recovery.

When should you worry and consult?

Some warning signs require prompt consultation:

• Pain that worsens at night and wakes you up
• A suddenly hot, red and swollen knee
• A feeling of instability or joint locking
• A limp that settles in over time
• A sudden loss of flexion or extension mobility

In these cases, a rheumatologic or orthopaedic opinion is needed before resuming any physical activity.

The role of the sport-health coach

Resuming physical activity with gonarthrosis is not about signing up at just any gym. A specialised sport-health coach will first assess your situation: mobility, muscle strength, balance, triggering pains. Then they will build a progressive, safe programme adapted to your daily life.

At home, the advantage is twofold: no logistics (no travel, no fixed schedule) and an environment where the coach can show you how to adapt your daily gestures (getting out of bed, going down stairs, doing the shopping). It is in this anchoring of movement in everyday life that progress settles in for the long term. We work in Nice, Antibes, Cannes and Monaco. Our sport-health approach is specifically designed for people with joint conditions.

Summary

Knee osteoarthritis is not a sentence to immobility. Injections relieve pain — useful, sometimes essential. But it is movement that changes the ground: it nourishes the cartilage, strengthens the stabilising muscles and preserves your independence. The combination of both, under the watch of a professional, is the formula that truly transforms the daily life of people who suffer from gonarthrosis.

Frequently asked questions about knee osteoarthritis

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