Meniscus tear grades describe what the MRI shows, from grade 1 to grade 3. Grades 1 and 2 are changes inside the meniscus that do not reach its surface, and in most cases they are not a true tear. Grade 3 is a real tear that reaches the surface. But the grade alone does not decide treatment: the tear’s location, its pattern and your symptoms matter more than the number in the report. Prof. Dr. Ibrahim Shaarawi, Professor of Orthopaedic Surgery, explains how to read your MRI report and what it means for you.
Key takeaways
- Grades 1 and 2: signal inside the meniscus that does not reach the surface. It usually means degeneration or bruising and is treated without surgery.
- Grade 3: a true tear reaching the surface. Not every grade 3 tear needs an operation; the decision depends on symptoms and tear type.
- Location decides healing potential. The outer third (red zone) can heal; the inner third (white zone) rarely does.
- Meniscal changes on MRI are very common after 50, even in people with no knee pain, so the MRI is always read together with the clinical examination.
How is a meniscus tear graded on MRI?
A healthy meniscus looks uniformly black on MRI. When its tissue changes, a bright signal appears inside it. The most widely used grading (the Stoller classification) is based on the shape of that signal and whether it reaches the meniscal surface:
| Grade | MRI appearance | What it means | Usual treatment |
|---|---|---|---|
| Grade 0 | Uniformly black meniscus | Normal meniscus | None |
| Grade 1 | Round bright spot inside the meniscus, not reaching any surface | Early degeneration or bruising, not a tear | No specific meniscus treatment |
| Grade 2 | Bright line inside the meniscus, not reaching the surface | Deeper internal degeneration, still not a true tear | Conservative care and physiotherapy |
| Grade 3 | Bright line reaching the upper or lower surface | A true tear | Conservative or arthroscopic, depending on symptoms and type |
Some reports and websites mention a grade 4. It usually means a complex, multi-directional tear or a badly frayed meniscus. It is not part of the original classification, but in practice it describes a severe grade 3 tear.
Grade 1: should you worry?
Usually not. Grade 1 is a minor change in the meniscal tissue that is common with age or after a knee bruise. It does not reach the surface, so it does not lock the knee and does not need arthroscopy. If your knee hurts and the MRI shows only grade 1, the pain probably comes from something else. Kneecap problems, early osteoarthritis and tendon irritation should all be considered.
Grade 2: does it need surgery?
In the great majority of cases, no. Grade 2 is a line inside the meniscus that does not break its surface, so the meniscus is still intact on the outside. Treatment is thigh strengthening, temporary activity modification and pain relief when needed. See non-surgical treatment for a meniscus tear.
A grade 2 line is sometimes read as grade 3 or vice versa, especially in the posterior horn of the medial meniscus. That is why the surgeon reviews the images personally alongside the examination rather than relying on the written report alone.
Grade 3: when is arthroscopy needed?
Grade 3 is a true tear, but not every true tear needs surgery. Arthroscopy is usually considered for:
- Mechanical symptoms: the knee locks and cannot straighten, or something catches inside it.
- A repairable tear in an active young patient, especially a longitudinal red-zone tear or a root tear.
- A bucket-handle tear flipped into the joint.
- Persistent pain despite 6 to 12 weeks of structured conservative treatment.
- A tear with an ACL rupture, treated at the same operation.
A degenerative grade 3 tear in someone over forty, without locking, is best started with physiotherapy. Large randomised trials show results close to those of arthroscopy. Full details are on our arthroscopic meniscus surgery page.
Location matters more than grade: the three zones
The meniscus gets its blood supply only from its outer rim, so it is divided into three zones that predict healing:
| Zone | Location | Blood supply | Healing potential |
|---|---|---|---|
| Red-red | Outer third | Good | High; suitable for repair |
| Red-white | Middle third | Limited | Moderate; repair possible in selected cases |
| White-white | Inner third | Almost none | Very poor; trimmed if treatment is needed |
That is why a grade 3 tear in the red zone may be repaired and heal, while a tear of the same grade in the white zone will not. Learn more about meniscus repair and whether a torn meniscus heals on its own.
Tear patterns
- Longitudinal: runs along the length of the meniscus; the most suitable for repair.
- Bucket-handle: a large longitudinal tear that flips inward and locks the knee.
- Radial: cuts from the inner edge outward; it weakens the meniscus badly if it reaches the rim.
- Horizontal: splits the meniscus into two layers; common in degenerative tears.
- Flap: a loose piece that can catch during movement.
- Complex: several directions at once, usually degenerative.
- Root tear: the end of the meniscus detaches from bone. It needs prompt assessment because it speeds up osteoarthritis.
How to read your MRI report
Common phrases and roughly what they mean:
- “Grade II signal” or “intrasubstance degeneration”: signal inside the meniscus that does not reach the surface. Not a tear.
- “Tear extending to the inferior articular surface”: a grade 3 tear reaching the lower surface.
- “Posterior horn of the medial meniscus”: the back of the inner meniscus, the commonest site of tears.
- “Displaced fragment” or “double PCL sign”: a flipped fragment, which may indicate a bucket-handle tear.
- “Meniscal extrusion”: the meniscus pushed out of place; it may accompany a root tear or osteoarthritis.
Frequently asked questions
Does a grade 2 meniscus tear heal?
Grade 2 is not an open tear but a change inside the tissue. It does not “heal” in the sense of disappearing from the MRI, but symptoms usually improve with physiotherapy and surgery is not needed.
Does grade 3 always mean surgery?
No. The decision depends on symptoms (especially locking), your age and activity level, and the type and location of the tear. Many degenerative grade 3 tears improve without surgery.
Can a tear progress from one grade to another?
Yes. Degeneration can turn into a tear over time, especially with excess weight or repeated twisting and deep loaded squats. Strong muscles and a healthy weight lower that risk.
Want an opinion on your MRI?
An MRI report is a starting point, not a treatment decision. Bring the images themselves (not just the report) to be reviewed together with a knee examination by Prof. Dr. Ibrahim Shaarawi. Book a consultation, message us on WhatsApp at +20 155 554 7181, or call +20 155 240 4488. You may also want to read about meniscus tear symptoms.
Medically reviewed by Prof. Dr. Ibrahim Shaarawi, Professor of Orthopaedic Surgery. This article is general medical education and does not replace a personal consultation. See our medical disclaimer.
References
- Stoller DW, Martin C, Crues JV 3rd, Kaplan L, Mink JH. Meniscal tears: pathologic correlation with MR imaging. Radiology. 1987;163(3):731-735.
- Arnoczky SP, Warren RF. Microvasculature of the human meniscus. Am J Sports Med. 1982;10(2):90-95.
- Englund M, et al. Incidental meniscal findings on knee MRI in middle-aged and elderly persons. N Engl J Med. 2008;359(11):1108-1115.
- Katz JN, et al. Surgery versus physical therapy for a meniscal tear and osteoarthritis. N Engl J Med. 2013;368(18):1675-1684.
- Beaufils P, et al. Surgical management of degenerative meniscus lesions: the 2016 ESSKA meniscus consensus. Knee Surg Sports Traumatol Arthrosc. 2017;25(2):335-346.