A knee meniscus injury is a crack or tear in one of the two fibrocartilage pads between the femur and tibia. The menisci help distribute load, absorb some impact, and contribute to knee stability. This page provides general information: diagnosis and treatment should be tailored to each person after a medical assessment.
How does a meniscus injury occur?
An acute tear can occur when the knee twists under load, such as during a change of direction, landing, squat, or sports movement with the foot planted. It may occur alone or with another injury, such as an anterior cruciate ligament sprain. A degenerative tear develops more gradually in a meniscus that has become less flexible; an ordinary movement may then trigger symptoms without major trauma. Age, osteoarthritis, repeated loading, and previous injury can all influence this process.
Common symptoms
Pain is often located along the inner or outer joint line of the knee. It may increase with stairs, running, pivoting, squatting, or kneeling. Delayed swelling after activity, catching, painful clicking, or reduced range of motion may occur. An MRI finding of a meniscal tear does not automatically explain pain: some degenerative tears are present without symptoms, and the source may instead be the kneecap, cartilage, ligaments, tendons, or osteoarthritis.
How is the diagnosis made?
Diagnosis starts with the injury history and a clinical examination. The physician asks about the mechanism, timing, pain location, episodes of swelling, locking, and functional limitations. Both knees are compared, including joint-line tenderness, range of motion, effusion, ligament stability, strength, and pain during rotation or flexion manoeuvres. No single test is sufficient; findings are interpreted together with the history and the broader examination.
Differential diagnoses may include a ligament sprain, osteochondral injury, fracture, patellofemoral pain, tendinopathy, bursitis, osteoarthritis, or, less commonly, infection or inflammatory disease. Distinguishing these conditions matters before selecting rehabilitation, an injection, or surgery.
When is an MRI indicated?
MRI shows the menisci, ligaments, cartilage, and bone in detail. It may be useful when the examination leaves important uncertainty, symptoms persist despite initial care, a significant injury has occurred, or surgery is being considered. It is not always necessary on the first day: the clinical examination guides interpretation of the image and helps distinguish a common finding from a tear that is actually causing symptoms. An X-ray may also be appropriate to look for a fracture or assess osteoarthritis, even though it does not directly show the meniscus.
Conservative treatment and rehabilitation
When there is no true locked knee, unstable tear requiring intervention, or other urgent indication, conservative treatment is often reasonable. It may include temporarily reducing pivots, running, and deep flexion that clearly worsen symptoms while maintaining tolerated activity. Ice, relative rest, and medication recommended by a healthcare professional may help with symptom relief when appropriate for the individual.
- Physiotherapy and exercise: mobility, quadriceps activation, hip and trunk strength, balance, and knee control are progressed according to pain and function.
- Load progression: walking, stairs, partial squats, and then sport-specific drills are resumed gradually while monitoring the response over the following 24 hours.
- Sport and work modification: cutting, impact, and kneeling can be modified temporarily rather than avoided indefinitely.
For general information about assessment and sports medicine options, see the PRP service and sports medicine services page. The appropriate plan depends on the tear pattern, age, coexisting osteoarthritis, goals, and symptom trajectory.
When is surgery considered?
An orthopaedic consultation may be appropriate for a truly locked knee, a displaced or unstable traumatic tear, an associated ligament injury requiring an operative strategy, or persistent limiting symptoms despite a well-followed rehabilitation programme. Depending on the tear, options may include meniscal repair to preserve tissue or partial meniscectomy, which removes only the unstable portion when repair is not feasible. The decision considers the blood supply to the area, tear shape and stability, cartilage health, biological age, and functional goals. Surgery is not automatically the best response to a degenerative tear seen on MRI.
What is the role of PRP?
Platelet-rich plasma (PRP) may be discussed in selected cases, including a symptomatic degenerative meniscal tear when surgery is not the first option, or during recovery after partial meniscectomy depending on the persistent problem and the involved structures. It cannot mechanically stitch a displaced meniscus and does not replace assessment when locking or an unstable tear is suspected.
Evidence for PRP after partial meniscectomy and for degenerative tears remains variable across studies, depending on the preparation, technique, indication, and outcomes measured. Some people may experience symptom relief, but the benefit is neither guaranteed nor uniform. PRP should be considered after discussing alternatives, evidence limits, contraindications, and goals, and it generally forms part of a rehabilitation programme. The PRP knee injection overview describes the procedure in general terms; the pricing page provides administrative information separately and does not replace a clinical discussion.
When should you consult?
A routine medical assessment is appropriate if pain persists, swelling recurs, the knee feels unstable, activities or sleep are limited, or symptoms return every time sport is resumed. Seek prompt care after significant trauma with deformity, inability to bear weight or move the knee, very rapid swelling, a hot knee with fever, unusual severe pain, numbness, or rapid worsening. A completely locked knee warrants urgent assessment.
This page is for general information only and does not replace a medical consultation. Diagnosis, treatment options, the need for MRI or surgery, and the appropriateness of PRP must be assessed by a qualified healthcare professional based on your situation.