The meniscus is commonly injured with twisting movements where the cartilage is stressed by the twisting or torsion force and causes a tear.
As the meniscus acts as a stabiliser and a shock absorber it is vitally important for the correct functioning of the knee. Previously a bad meniscal tear would mean having a complete menisectomy (removal of the meniscus) this however saw a dramatic increase it the amount of knee arthritis and is now not commonly performed.
The meniscus is living tissue that is able to remodel and repair minor tears. The blood supply is good to the outer meniscus as such it is able to repair those tears. The blood supply to the internal meniscus however is poor and therefore recovery is generally slower and large tears may require surgery. Surgery however has to be a last resort as trimming the meniscus will cause a decrease in the amount of shock absorption material. The less meniscal tissue there is the less synovial fluid that is produced to lubricate the joint so the more wear and tear that will result. Lately there have been experiments injecting stem cells and growth factors in the knee to help stimulate repairs however this is still
in the early stages of development.
Types of tears:
- Longitudinal meniscal tear.
- Transverse vertical meniscal tear.
- Bucket handle meniscal tear.
- Flap meniscal tear.
- Torn horn meniscal tear.
There are two methods of meniscal injuries:
- An acute tear.
- Degenerative changes due to minor tears.
The common mechanism of injury for the meniscus is when the knee is bent and then twisted. This may occur on its own or from and external force such as a tackle in football.
Medial menical tears are far more common than the lateral meniscus tears. Due to the attachment of the medial collateral ligament into the meniscus, meniscal tears often occur in conjunction with a medial collateral ligament sprain and sometimes an anterior cruciate ligament sprain. When all three are injured it is known as the “terrible triad” or the “unhappy triad”. This generally occurs when the knee is hit from the side and it gives out in a medial direction. A lengthy recovery period will result following this.
As you get older the cartilage begins to wear out. There becomes less moisture content in the meniscus and it becomes less of a shock absorber and becomes more susceptible to tears. Quite often little tears will develop and as they progress the shock absorption capabilities of the knee will reduce resulting in degeneration of the knee. If the degeneration progresses far enough you will need a complete knee replacement.
Some patients describe a sharp pain or hear an audible click as they injure their meniscus:
- Pain is generally localised to the side where the tear is located.
- Your knee may become quite swollen.
- Your knee can lock and you will be unable to fully straighten or bend your knee.
- Your knee may occasionally give way on you.
- You may develop a clicking or catching as you move your knee.
- RICED (Rest, Ice, Compression, Elevation and Diagnosis) to help the symptoms settle.
- Specific massage to help remove swelling and free up tight structures, incorrect massage may aggravate the knee.
- Physiotherapy mobilisations to restore movement to the knee.
- Proprioceptive rehabilitation for return to sports.
- Taping or strapping techniques to support the knee on return to sports or activities.
Pre surgical physiotherapy:
Physiotherapy pre surgery is vitally important as the stronger your knee is before the operation the shorter your recovery period will be. This means you will return to work faster and be able to return to sport much quicker. Pre operative physiotherapy is often overlooked but we would say it is just as important as the exercises that follow your operation. It is also very simple and often requires very few treatment sessions.
Post surgical physiotherapy:
Physiotherapy is integral post operatively to ensure full function is restored to your knee and you progress at a rate that ensures full recovery to your knee. Your immediate post surgical physiotherapy will begin with a strict icing protocol and certain range of movement exercises. Strengthening will be started to ensure you have full control off your knee. You will be given progressions for these. You will most likely be given these exercises from your specialist or from the in hospital physiotherapist. These exercises will be great during the initial stages of recovery but it is important to receive treatment and a full assessment as you recover to ensure you are fully recovered and you have removed any predisposing factors that may cause further injuries. A common one being a lack of core strength and stability causing extra stresses on the knee. The last thing anyone wants is to do exactly what they were doing before and end up with the same result – being injured again.