Meniscus injuries – keyhole surgery of the knee

DR. DEPAEPE

1. ANATOMY

The meniscus is a semicircular, rubbery disc made of a special type of cartilage, which is located between the upper leg (femur) and lower leg (tibia). There is an inner C-shaped (medial or internal) and an outer 0-shaped (lateral or external) meniscus. Each meniscus consists of 3 parts: the posterior horn, the corpus (body) and the anterior horn. Three zones are also distinguished in the meniscus: an outer 1/3 zone (the red zone) with good blood circulation, a middle 1/3 zone (the red-white zone) with an average blood supply and an inner 1/3 zone (the white zone) without blood supply.

The inner meniscus is firmly connected to the capsule of the knee, the outer meniscus, on the other hand, is not tightly connected to the capsule and is therefore much more mobile.

2. FUNCTION

The meniscus mainly has a shock-absorbing function. By absorbing the shocks, the overlying and underlying cartilage is better protected. In addition, a meniscus also contributes to the stability of the knee (in addition to the ligaments). The meniscus also plays a role in the nutrition of the cartilage that covers the joint surfaces.

3. CAUSE OF MENISCUS TEAR

Door een verkeerde beweging bv. draaibeweging vanuit gehurkte houding, plotse draaibeweging tijdens sporten kan een meniscus scheuren (traumatische meniscus scheur). De meniscus kan ook inscheuren bij een zeer klein trauma, wanneer deze door een eerder slijtageproces (uitrafeling) reeds fors verzwakt is (degeneratieve meniscus scheur of slijtage scheur).

Meniscus tears occur in every age category. In the younger group, it is more likely to involve isolated traumatic meniscal injuries. In the older group, this mainly concerns degenerative cracks and there will be frequent accompanying cartilage lesions (wear and tear). The latter determine whether or not the knee will become pain-free after treatment.

The type of accident and the quality of the meniscal tissue determine which type of tear injury occurs.

4. COMPLAINTS OF A MENISCUS TEAR

Not every meniscus tear causes complaints! The load depends on the type of crack and the location of the crack. The body weight, the axis of the leg and the degree of physical activity also determine the complaints.

• Pain: is mainly present during deep flexion and full extension of the knee. This pain decreases little by little after the accident.
• Stiffness: is usually most present in the first period after the accident.
• Swelling: is the result of fluid accumulation or bleeding within the knee.
• Blocking: If part of the meniscus becomes wedged between the upper leg and lower leg, the knee can no longer be fully bent or straightened.
• Sagging feeling: feeling of not standing firmly on your leg and bending at the knee.
• “Click”: sometimes there is a palpable or audible click in the knee joint.

5. RESEARCH

A good one clinical research from the doctor may suggest the diagnosis.

Radiography: of the knee gives us an idea of ​​the amount of wear and tear on the joint.

MRI scan: is often the appropriate examination to visualize a meniscus tear.

CT scan with contrast fluid (arthro-CT) is sometimes used if significant additional cartilage damage is already suspected.

6. TREATMENT

The treatment depends on the type of tear, the size of the tear, the location of the tear, the quality of the meniscus tissue and the age. Not every meniscus tear is treated surgically.

Bij jonge mensen worden de accidentele scheuren behandeld met een kijkoperatie. Bij de groep van “degeneratieve scheuren” bij patiënten boven de 50 jaar wordt getracht een onderscheid te maken tussen “stabiele” en “niet-stabiele” meniscus scheuren. De eerste behandeling bij stabiele degeneratieve scheuren zal niet operatief zijn. Zo er na maanden nog klachten blijven bestaan, kan dan alsnog beslist worden om een kijkoperatie uit te voeren.

NON-OPERATIVE TREATMENT

• Rest, ice applications.
• Anti-inflammatory medication to reduce pain and inflammation.
• Injection with a cortisone preparation to reduce pain and inflammation, with hyaluronic acid to protect cartilage or sometimes with PRP.
• Muscle strengthening exercises and physiotherapy.

OPERATIVE TREATMENT: EXPOSURE OPERATION OR ARTHROSCOPY OF THE KNEE

A camera and several specific instruments are inserted into the knee through two small openings of a few millimeters. During arthroscopy, the joint is filled with fluid, so that there is more space in the knee and the joint can be continuously flushed. The purpose of keyhole surgery is not just to look, but also to solve the problem!

Partial or partial menisectomy

If the meniscus has suffered irreparable damage, the tear is removed during keyhole surgery with special instruments. This mainly concerns tears in the inner part of the meniscus where there is no or insufficient blood supply (white zone, see section 1). Naturally, only the damaged part is removed, the remaining part of the meniscus is preserved. In this way, a large part of the shock absorber is retained and the risk of osteoarthritis is kept to a minimum. This is the most commonly performed arthroscopic procedure in the world with favorable results.

Meniscus suture

Recent tears in the red, well-vascularized area (see section 1) are candidates for suturing. The decision to suture is often made during keyhole surgery. The torn fragments are stitched back together using special anchors and wire.

The major advantage of a suture is that the meniscus can retain its full function. The disadvantage is that the meniscus needs time to heal, which means there are certain restrictions during the first 3 months after surgery. This is to give the meniscus the opportunity to grow back into place. This bonding should be seen as a long-term investment.

Unfortunately, meniscal sutures only heal in a maximum of 8 out of 10 cases, so a repeat procedure is sometimes necessary later.

Artificial meniscus or meniscus scaffold

Indien een groot deel van de meniscus verloren gaat wordt er soms nagedacht om dit op te vangen. Een van de mogelijkheden is het inplanten van een soort kunstmeniscus waar lichaamseigen cellen kunnen ingroeien om te ontwikkelen tot meniscus-achtig weefsel. Deze behandeling wordt heden vooral nog toegepast in studie verband en is zeker geen frequent toegepaste techniek.

Meniscal transplant

In young people where a severely damaged meniscus had to be almost completely removed and where the cartilage is still completely intact, a meniscus transplant is sometimes considered. The entire meniscus is replaced by a donor meniscus via keyhole surgery. There are often long waiting lists to find a suitable meniscus donor.

ANESTHESIA AND HOSPITAL STAY

The procedure is performed as a day hospital and can be done via an epidural or short general anesthesia.

7. COMPLICATIONS

• Bleeding from the wounds or bleeding in the knee. We try to prevent this by applying lots of ice.
• The wounds (no matter how small) can sometimes remain sensitive for a while after keyhole surgery.
• Persistent pain complaints. Sometimes there are associated cartilage lesions associated with degenerative meniscus tears that cannot be resolved with keyhole surgery. This will be discussed with your doctor upon consultation.
• Infection: very small chance because extensive rinsing is done during keyhole surgery.
• A blood clot or phlebitis may form in your operated leg. We always give injections in the first week and we try to move as quickly as possible to reduce that chance to almost zero.
• Damage caused by keyhole surgery to structures around the knee, such as nerves or blood vessels, is very rare.

8. REHABILITATION

Partial or partial menisectomy

It is best to use crutches for 5 days to give the knee a rest and avoid swelling. Afterwards, support is fully permitted.

During your stay at the day hospital, you will be taught exercises that you can perform every day. If necessary, you will receive a prescription for physiotherapy.

As soon as cycling is possible, you can cycle unloaded, for example on an exercise bike.

Meniscus suture

During the first 3 weeks you will have to walk between crutches without fully supporting your leg. Only the toes should touch the ground. The physiotherapist will teach you how to use the crutches.

You will receive a prescription for physiotherapy and these guidelines must be followed.

Deep folding beyond 90° is not recommended for the first 6 weeks to limit tension on the suture. A knee brace is usually used to prevent it from bending over 90°.

9. FACTS

• Try to control the pain with prescribed painkillers and ice applications.
• Hou de wondjes proper en droog. Douchen is toegestaan met een douche pleister ( opsite, tegaderm, ..) De hechtingen kunnen na 14 dagen verwijderd worden door de thuisverpleging of uw huisarts.
• Injections in the abdomen are recommended for the first 10 days (blood thinners to avoid phlebitis). You will receive a prescription for home care, the nurse at the day hospital can also teach you how to do it. If you are already taking blood thinners before, this may differ from the normal schedule.
• Incapacity for work is between 3 days and 6 weeks and depends on the content of the job. The way you travel to work is also important. Discuss this with your doctor before the procedure.
• You can start driving when the knee feels reliable, strong and stable. It is also important that the knee bends at least 90°. A normal gait and walking down stairs without using the handrail provide a good indication of muscle control around the knee. For most people this is about 1 to 3 weeks after the procedure.
• Sports resumption. Your physiotherapist and surgeon will advise you when it is safe to resume your hobbies. This will depend on the type of sport and the level at which you practice it. Cycling is the ideal activity to make the knee flexible again and to train the thigh muscles without overloading the knee. Sports activities can be resumed gradually after 4 to 6 weeks if the pain and swelling have disappeared sufficiently.
• These facts apply to a partial menisectomy. The guidelines after meniscus suturing or other meniscus procedures may differ significantly and will be discussed with you by the doctor.