Meniscus injury

Meniscus injury is very common in sport traumatology. There are two menisci in the knee (medial meniscus and lateral meniscus). They are both triangular fibrocartilages, interposed between femur and tibia.  Semicircular wedge shapes, they allow a good congruence between the femoral condyle and the tibial plateau. In response to axial loads, the menisci provide a protective load transmission and energy resorption: they can be considered to act like "shock absorbers". (more details about knee anatomy ...) 

What you have to know...

Total meniscectomy (surgical remove of the meniscus) lead in the long term to osteoarthritis of the knee, in particular if the anterior cruciate ligament is torn. It is therefore necessary to try to preserve as much of the meniscus as possible, performing “minimal” partial meniscectomy utilising arthroscopy. Meniscal repair must be always practised, if it is possible in meniscus injury; in particular for peripheral injuries in young patients.

Signs and symptoms

A meniscus injury can occur at any age: in young patients a torn meniscus is usually the result of twisting injuries to the knee, whereas in older patients, we find degenerative lesions. Twisting injuries to the knee can be the origins of other ligamentous injuries (MCL and  anterior cruciate ligament tear). Another mechanism, often observed among more elderly patients "in later years", is a hyperflexion followed by a forced lifting: the meniscus overlapped by the internal condyle is crushed, rolled and tears. A meniscal portion may be luxated in the notch: it is a “true locking” (meniscal locking) (impossibe to fully extend the knee). The cause is a bucket handle meniscus tear. A cracking can be felt by the patient associated with a sharp pain. 

Diagnosis

A diagnosis may be easily obtained; investigation of the reason for consulting the doctor (history of present complaint)  combined with a comparative clinical examination of the two knees. A fixed flexion deformity is always investigated with or without the presence of an effusion. The clinical examination looks for pain during direct palpation of the medial and lateral meniscus and other signs of meniscal lesions with specific tests ( Mc Murray, Grinding-test of Cooper-Appley).

Radiographs

Simple x-rays are necessary to eliminate a bone lesion or ostheochondral,  even if they are generally normal. X-rays are very important (in particular using the "Rosemberg view") to detect an initial osteoarthritis, that may be associated with a meniscal tear. An arthrography visualizes the contours of the menisci: it is a reliable diagnostic method to visualize méniscal injuries. A ct-scan can also be used to evaluate the menisci.

MRI (Magnetic Resonance) is a more reliable examination for the diagnosis of a meniscus tear.

Arthroscopic Surgery

Surgical techniques used to remove or to repair the meniscus (meniscus repair) are performed in arthroscopy. With only a small skin incision it is possible to introduce a minute camera into the knee. Exploration of the articulation begins; the surgical procedure is practised using very small grips, which are introduced by a second small incision. The menisci are thus repaired - if the rupture allows it - or removed partially.

Meniscus rehabilitation

Arthroscopy considerably simplifies post-operative recovery. After medial meniscectomy, the patient can walk the day after surgical procedure and will recover his articular motion completely (complete flexion). Often meniscus rehabilitation is advised: electrostimulations, stretchings and proprioceptive rehabilitation can accelerate recovery.  A lateral meniscectomy may be followed by some swelling during the first weeks. Meniscus repair  requires, on the other hand, a different rehabilitation regime. To protect the suture flexion is limited for 4-6 weeks; complete weight bearing is generally allowed, but only when supported by two crutches.

Frequent questions

How long is it necessary to wait before continuing sport  after a meniscectomy in arthroscopy?  

Generally, contact sports (football, Rugby, handball, etc.) may be resumed 4 to 6 weeks after intervention. Bicycling, walking and swimming are possible after 15 days. It is essential to  use common sense when resuming sports activities. It should always be done progressively and reasonably.

Is it necessary to walk with two crutches after an arthroscopic partial meniscectomy ?

No; complete weight-bearing is allowed the day after intervention, but it is better (for the first 2-3 days) to remain at rest with the knee elevated and to use ice packs.   

How many days of hospitalization are likely to be necessary?

Hospitalization time is very short: knee arthroscopy is carried out during day-surgery; however for geographical reasons (distance), family problems (somebody who lives alone), medical, even suitability, a 48 hours period of hospitalization is advised.

And if I don’t want to undergo surgery?

A suturable rupture can become insuturable with time. Meniscal lesions can be the cause of articular crises (pains, blockings, swelling) which can occur constantly, sometimes resulting in the patient having to cancel projects or appointments at the very last minute. In addition physical or sporting activities can be severly limited for long periods.

How long is necessary it to stop work after an arthroscopy?

Schoolpupils will need to take a break of about 3-4 of days. For  “manual” workers (mechanics, electricians etc.) it will be necessary to stop working from 2 to 4 weeks. For a sedentary job 2 weeks are often sufficient. Nevertheless the knee can remain weak for a period of 4 to 6 weeks.  

How long after the intervention can I drive the car ?

In general, 48 hours after surgery you can regain a very quiet everyday lifestyle (climb stairs, drive a car...). Nevertheless reaction times will be reduced during 4 weeks. Whilst it is possible to drive, great care must be taken.    

Can I take a shower after the surgical procedure?

Personal hygiene before and after any intervention in orthopedic surgery is very important: nevertheless, the small skin incision should not be allowed to get wet - by taking a bath for example, because the risk of infection is very high if the wound does not heal properly. These days, special tight bandages are available which allow one to take a shower without problems.  

When is it necessary to remove the suture wires?

Wires fall out between 10 -15 days, if they are the resorbable type. If not, they should be removed approximately 14 days after intervention (which should be a painless experience....).