The medial and lateral menisci are fixed between the two weight-bearing surfaces within the knee, and as such can become “pinched” by the other structures of the knee between the joint when an injury occurs. Typically, the injury involves twisting on a bent knee. When this happens the menisci can become torn (“torn cartilage”). Any form of physical movement can potentially cause a meniscal tear, although they tend to be associated with sporting activities. A classic example is of a footballer tackling another player, but meniscal tears can occur following everyday pursuits, such as gardening or even just taking a long walk.
Most of the meniscus does not have its own blood supply, and so cannot always get the nutrients needed for self-repair. Whether or not the meniscus can heal therefore depends on where it becomes torn. Tears on the outer rim of the meniscus, which attaches to the knee capsule, do have the potential to heal because they are close to a blood supply. However, the more common site for meniscal tears is on the peripheral rim, or the inner aspect of the meniscus, and these have no capacity for self-repair.
The classic symptom of a torn meniscus is pain, often felt as a sharp, almost “knife-like” stabbing sensation on the inside (medial tear) or outside (lateral tear) of the knee. This pain is often felt in waves, with bouts of severe discomfort, followed by no pain, felt over the course of several days/weeks. However, the pain may also be felt as an aching sensation or even just as stiffness of the knee. The knee may also become swollen or “locked” in place, making it impossible to straighten it, or even collapse, or give the impression that it will collapse, from beneath you.
A meniscal tear can be diagnosed based on your description of how your injury occurred, and by taking a specialized photograph of your knee known as a magnetic resonance imaging or MRI scan. An MRI scan uses very strong magnetic fields to look at the inside of the knee, and allows all the soft tissues, ligaments and cartilage to be seen clearly. X-rays are not very useful in making a diagnosis, as these show only the bony structures of the knee, but may be used in the emergency setting to check that there are no broken bones.
Meniscal tears are treated using arthroscopic or keyhole surgery, but not everyone will need surgery. As with all injuries there are options and the most important thing to be considered is the level of discomfort and whether it interferes with your ability to function normally. All surgical procedures carry some element of risk, and your doctor must ensure that the benefits of any treatment you receive outweigh any potential risks.
Arthroscopic surgery is usually performed as a “day case,” meaning that you can go home the same day as the operation. Some people may need to stay in hospital for a couple of days to recover from the operation, but your surgeon will advise you on this.
This depends on the procedure being performed, but in the case of arthroscopic meniscectomy, which is the commonest procedure, you will generally be able to walk unaided the same day. Your doctor will recommend that you take at least four to five days off work. The time needed will depend on the type of work that you do, and people with physically demanding jobs may be advised to take a minimum of two weeks off work.
Although it depends on your injury and the type of surgery being performed, you should start to feel better within a couple of weeks and may be able to participate in certain sporting activities (eg, going to the gymnasium) approximately a month or so after the operation. It could, however take several months before you are able to train fully or as you would normally. Your doctor will again advise you on details of this.
The ACL is a ligament in the middle of the knee that connects the tibia (shinbone) to the fibia (thighbone).
A key feature of a serious ACL injury is a feeling of instability (i.e. that the knee may collapse from underneath you).
Not always. Some people are able to function normally without surgery, so long as they have physiotherapy, but others need reconstructive surgery no matter how much physiotherapy they have. Whether or not you have your ACL reconstructed also depends on how active you are, and how your injury impacts on your daily and sporting activities.
Early surgical intervention to repair a torn ACL is not recommended in the vast majority of cases, and physiotherapy for at least four to six weeks is almost always recommended first in the amateur sportsperson. This approach has the advantage of allowing any other associated injuries to settle, and any inflammation to subside. Taking time to have physiotherapy also gives the patient and physiotherapist the opportunity to assess whether they feel there is a genuine need for reconstruction.
Many older people find that wearing a well fitted, ACL-specific knee brace gives them the confidence and stability to return to the sport they enjoyed previously without the need for surgery.