Knee Pain Grades:

Can Strengthening and Stretching Help?

Knee pain does not always mean the knee is permanently damaged.

For knee osteoarthritis, doctors commonly use the Kellgren–Lawrence scale from Grade 0 to

Grade 4, based on an X-ray. However, the X-ray grade and pain level do not always match.

Grade 0 — No Osteoarthritis

• No visible joint damage

• Pain may come from weakness, stiffness, overuse or poor movement

• Excellent potential for improvement

• Focus on technique, strength, mobility and load management

Grade 1 — Very Early Changes

• Possible small bone spurs

• Little or no joint-space narrowing

• Occasional pain or stiffness may occur

• Very good potential to control symptoms

• Consistent exercise may help prevent further loss of function

Grade 2 — Mild Osteoarthritis

• Definite bone spurs

• Possible mild narrowing of the joint space

• Pain may appear during stairs, squats or longer activities

• Good potential to reduce pain and improve function

• A structured strength programme is strongly recommended

Grade 3 — Moderate Osteoarthritis

• Clear joint-space narrowing

• Multiple bone spurs

• More frequent pain, swelling or stiffness

• Strength and mobility training can still provide meaningful improvement

• Training should be personalised and professionally supervised

• Running or jumping may need to be temporarily reduced or modified

Grade 4 — Severe Osteoarthritis

• Severe loss of joint space

• Significant cartilage and bone changes

• Pain may affect walking and daily activities

• Exercise can still improve strength, mobility and quality of life

• However, it cannot reverse severe structural damage

• Medical treatment or joint-replacement assessment may be required

Which Grade Still Has a Chance to Improve?

Every grade may gain benefits from suitable exercise.

• Grades 0–2: Best opportunity to control symptoms and restore function

• Grade 3: Pain and movement can still improve with supervised training

• Grade 4: Exercise remains helpful, but medical support may also be necessary

“Recovery” does not always mean rebuilding lost cartilage. It may mean:

• Less pain and stiffness

• Better walking and stair movement

• Stronger support around the knee

• Improved balance and confidence

• Returning to suitable daily activities

• Delaying or avoiding further functional decline

What Should Training Include?

• Quadriceps strengthening

• Glute and hip strengthening

• Hamstring and calf conditioning

• Ankle stability

• Balance and movement control

• Gentle knee mobility

• Suitable stretching for tight muscles

• Low-impact aerobic activity

• Gradual progression of training load

Strengthening is the main component.

Stretching can improve stiffness and movement, but stretching alone is normally insufficient.

Exercise is recommended for improving pain and function in knee osteoarthritis.

Programmes commonly include strengthening, range-of-motion and aerobic activities.

AAOS guidance on knee arthritis, AAOS arthritis exercise guidance

LGRA Coaching Message

Do not wait until your knee reaches Grade 4 before taking action.

Early and consistent strengthening gives you a better opportunity to maintain movement,

manage pain and protect your independence.

Even at an advanced stage, it is not “too late” to become stronger—but the programme must

match your condition.

This grading system applies specifically to osteoarthritis seen on X-rays, not every cause of

knee pain. Seek medical assessment for major swelling, locking, giving way, severe night pain,

inability to bear weight or pain following an injury.