Meniscal injuries

We get you back to work and sporting activity as quickly as possible with minimal disruption

Meniscal injuries are amongst the commonest problems seen by knee specialists at Schoen Clinic.

Whilst our knee specialists commonly treat professional sportsmen and women who have sustained meniscal cartilage injuries, the majority of our patients tear their cartilages undertaking relative routine day-to-day activities.

Meniscus: Structure and function

Every knee has two meniscal cartilages within it, one on the inner (medial) aspect of the knee and the other on the outer (lateral) aspect. Both act, together with the cushioning cartilage covering the ends of the bones as shock absorbers within the knee, also helping to provide stability to the joint.

These two C-shaped wedges of cartilage are made of a particular type of tough cartilage tissue, possessing the unique ability to absorb and dissipate the forces of day-to-day impact not only on sporting activity but also with every step you take.

However, as the knee does not act as a simple hinge, but also has a small degree of rotation within it, these rotating forces can on occasions lead to a pinching of the cartilage– thus causing damage. If an excessive amount of force, either as a direct result of a single twist or an accumulation of forces during unaccustomed exercise occurs, then the threshold for this structure can be exceeded, leading to a tear. Once the tear reaches the surface of the meniscal cartilage, healing of this is unlikely to occur.

It is for this reason that many cartilage injuries are very slow to settle, with many never settling at all, thus requiring surgical intervention.

Meniscus tear symptoms

A significant twisting injury whilst playing sport (e.g. football or skiing) may well result in a meniscal tear, but equally even day-to-day actions such as getting up from sitting on the floor (e.g. in a yoga class) can produce exactly the same result, especially in the older age group e.g. in orthopaedic terms this refers to patients over 40. After this age, the cartilage has started to turn from a very resilient, tough rubbery construct, to a more brittle one that is not as elastic as it once was. It is for this reason that a simple twisting injury can cause a small split within the cartilage.

The meniscus has a very limited capacity to heal by itself because the vast majority of it does not have a blood supply. This means that symptoms from a torn cartilage will often persist long after one would expect other injuries to have healed. It is not unusual for the sharp pain of the injury to improve after several weeks, only for it to return each time sport is attempted.

Some classical symptoms for meniscal injury include some or all of the following:
  • Occasional sharp stabbing pain on either the inside or outside of the knee
  • Limitation in the range of motion, particularly deep bending
  • Pain on kneeling/squatting
  • Pain climbing stairs
  • Pain made worse by exercising
  • A catching/clicking sensation
  • A feeling of ‘giving way’/instability
  • Pain at the back of the knee - often due to a Baker’s cyst (due to excess fluid related to the meniscal tear)
  • Pain from a torn cartilage may vary between a sharp stabbing pain to a dull ache and it may be intermittent or continuous
  • Occasionally, there is no pain at all associated with these injuries but simply an inability to completely straighten the leg, i.e., locked knee. This is caused by the torn meniscus jamming

Causes: How meniscal injuries occur

Meniscal injuries can occur at any age although, contrary to popular opinion, most commonly they are found in the older age group. As we age the cartilage material itself becomes more brittle, thus the tendency for it to tear increases significantly.

In the younger population, normally only significant trauma during sporting activity causes tearing, whereas, in the 40+ age group, tearing can occur more easily as a result of an accumulation of stresses, either during a single exercise or over a period of time. Consequently, it is not necessarily a single traumatic event sporting that can cause a meniscal tear, but quite often even simple day-to-day activities such as an unusually long walk or prolonged/unaccustomed exercise.

It is also possible to simply tear the cartilage in a single abnormal movement, for example when getting up from a kneeling or cross-legged position on the ground.

Diagnostics: We take a close look at your meniscus

The diagnosis of meniscal cartilage injury is made by a combination of a thorough consultation, where our experts at Schoen Clinic will listen to the history of the injury. A careful physical examination may reveal the following tell-tale signs of a meniscal tear, such as:

  • Fluid present in the knee, known as an “effusion”
  • Marked pain on direct compression of the meniscus along the joint line
  • Discomfort when squatting
  • Clicking within the knee
In addition, we may carry out imaging tests to create a comprehensive clinical picture. These can include x-ray examination to reveal the condition of your bones, and magnetic resonance imaging (MRI) for a detailed view of your soft tissues.

X-ray images to assess damage to your knee joint

X-rays can be useful in conjunction with MRI scans to assess concurrent bony pathology within the knee. X-rays reveal a clear picture of dense structures, like bone, which can assist in determining if there are any other potential causes for your pain like osteoarthritis, loose bodies or fractures.

Magnetic resonant imaging (MRI)

After an initial examination, your consultant may refer you for an MRI scan of your knee.

MRI scans produce high-resolution images of the soft tissues in and around the knee and are very useful to assess for cartilage tears. These scans have the advantage of not producing any harmful radiation. The high degree of definition within the MRI scan allows in-house radiologists to identify any tears within a meniscus with an extremely high level of accuracy (approx. 98%). By working exclusively with specialist radiologists with a clear interest in this area, this provides a very real diagnostic advantage for the surgical team as even subtle injuries will be detected.

It is, however, useful for consultants to have seen and assessed your knee prior to the MRI, as he or she will be able to tailor the scan request to assess the damaged part in question in more detail.

Identifying the type of meniscal injury is the key to deciding the right treatment

It would be a mistake to think that all cartilage tears are the same. Not only do cartilage tears vary, depending on whether they are on the inner (medial) or outer (lateral) side of the knee but also in the area of the cartilage that is torn as well as the configuration of the tear itself.

For example, tears towards the peripheral aspect of the meniscus may have a greater chance of healing as these are known as 'red/red' tears with a significantly better blood supply than the ones towards the inner aspect of the knee (white/white). The tears with poor blood supply, which represent the majority of injuries, unfortunately, have no capacity to heal as the blood supply does not bring in the appropriate materials to allow the repair to occur.

Equally, if the tear is a sideways split within the cartilage – known as a horizontal cleavage tear – these also tend to heal badly and are found in “older” patients, often with previous degeneration within the substance of the meniscus itself.

Perhaps the most common tear we see is an oblique under-surface tear that creates instability in the cartilage, thus creating traction on the very sensitive capsule attached, producing the sharp stabbing pain felt by the patient.

These tears, together with flap-type tears, can often cause significant sharp discomfort as well as occasional locking, as discussed earlier under the heading of symptoms. It is important to distinguish between the different types of tear, particularly if one thinks the whole of the cartilage has become displaced and flipped into the middle of the knee, which is referred to as a bucket-handle tear. In some instances, when the knee itself is locked, there is then a degree of urgency to proceeding to unlock the knee via surgery. This allows for potential repair to be undertaken.

Meniscal surgery

If the decision has been taken to proceed to surgery, as a result of persistent symptoms or a more acute need to unlock a knee, then the procedure to deal with the cartilage is usually referred to as a partial meniscectomy. This is a relatively straightforward keyhole operation carried out under general anaesthetic, lasting approximately 20-30 minutes.

The operation involves the insertion of a camera or arthroscope with miniature instruments into the knee through two small 4mm incisions in the front of the knee. The damaged part of the cartilage is trimmed and the residual rim of the cartilage is shaped to resemble the initial smooth surface. As little of the cartilage, usually approximately 20-25%, is removed as possible in order to preserve the function of the remaining healthy portion.

Once the whole of the inside joint cavity has been thoroughly inspected and any other defect or damage is noted, the instruments are removed and the incisions closed.

In a minority of patients, particularly the younger patients, the tear is within the healing red/red zone, discussed above, which has a good blood supply. These tears may be suitable for repair with internal stitches, rather than excision.

Obviously, where possible, any attempt to preserve the cartilage and its function is beneficial, particularly for the younger age group.

It is important to remember that the meniscus has a very important function and without the appropriate volume of meniscal tissue, the possibility of increased stresses occurring across the joint, leading to degenerative change in later life, is well established. It is for this reason that every attempt to try and be conservative during surgery is made.

Your surgeon will carefully go through the risks, benefits and alternatives for each procedure prior to any planned surgery.

In older patients, we know that the articular cartilage lining the joint may already be significantly diminished (osteoarthritis). In an osteoarthritic knee, the MRI scan may reveal a crushed and complexly torn meniscus. This is often referred to as a degenerate meniscal tear. Keyhole surgery to treat a degenerate meniscal tear may not only fail to treat the symptoms but may instead aggravate the knee further. A rare complication from arthroscopic surgery, possibly caused by the pressurised water, is spontaneous osteonecrosis (SONK). This tends to happen more commonly in patients over the age of 50 and is normally usually a self-limiting condition that settles over a period of months without any further treatment.

It is usual for you to be able to walk without sticks or crutches immediately after the surgery but we advise limiting walking to short distances for the first few days and outpatient physiotherapy soon after the surgery is also recommended.

It is important to build up gradually to normal activity levels, especially any sporting activity.

Driving is normally possible after two days, once you are confident enough to be able to do an emergency stop.

Meniscal injuries: Aftercare

After surgery, the knee is dressed with a woollen bandage and you will be encouraged to walk within an hour after you have woken up and have had a meal. You will be able to walk without sticks or crutches but we advise that limiting walking to short distances initially and build up gradually to normal activity. Driving is normally possible after two days and once you are confident enough to be able to do an emergency stop.

Any pain is normally controlled with a combination of anti-inflammatory drugs and painkillers, which may include simple paracetamol as well as some codeine and or anti-inflammatory medications such as ibuprofen. Physiotherapy should start within a few days of your discharge and plays a vital part in post-operative recovery.

You will normally be seen at Schoen Clinic two weeks after your operation to check wounds and to remove the stitches, if necessary. We expect you to be making good progress by this stage, but not to be fully recovered.

Generally, full recovery takes about six weeks, but most patients can return to work within the first week. However, attempting to do too much too early on, can often be counterproductive, irritating the sensitive remnant of the meniscus and causing a recurrence of pain.

It is very important for the knee to be given appropriate care and respect in the early stages including regular icing and the vast majority of patients will return to professional and amateur sports by six weeks post-surgery.

Meniscal injuries: Our specialists

Our knee specialists commonly treat professional sportsmen and women sustaining meniscal cartilage injuries, but the majority of our patients tear their cartilage undertaking relatively common day-to-day activities.

Meniscal injuries: Our specialised hospital

We pride ourselves on providing you with the best care for your meniscal injury. Our world-class multidisciplinary team and rapid recovery programme will enable you to return to normal in the shortest possible time.