Meniscus damage: causes, symptoms, diagnosis, treatment

Menisci are fibro-cartilaginous formations of a semilunar form. On a cut have the form of a triangle. The thick edge of the meniscus is turned on the outside and fused with the capsule of the joint, and thinned - inside the joint. The upper surface of the meniscus is concave, and the lower surface is almost flat.

Menisci serve as shock absorbers of the knee joint, softening shock loads in the joint and protecting the hyaline articular cartilage from traumatic effects. Changing their shape and moving in the joint cavity, menisci provide congruence of the joint surfaces of the femur and tibia. Bunches of popliteal and semimembranous muscles approach the meniscus, facilitating their movement inside the joint. Due to the connection of menisci with lateral ligaments, menisci regulate the degree of tension of these ligaments.

Circumference of the medial meniscus is greater than that of the lateral one. The internal distance between the horns of the lateral meniscus is half as long as the medial distance. The anterior horn of the medial meniscus is attached at the anterior edge of the articular surface of the tibia in the anterior intercondylar fossa. The attachment site of the lateral meniscus is located somewhat posteriorly, before the attachment of the distal end of the anterior cruciate ligament. The posterior horns of the medial and lateral meniscus are attached to the posterior intercondylar fossa of the tibia behind the tubercles of the intercondylar elevation.

The medial meniscus along the outer surface is tightly connected to the capsule of the joint, and in the middle part - with deep bundles of the medial lateral ligament. In comparison with the lateral meniscus, it is less mobile. The lateral meniscus is tightly connected to the capsule only in the area of its horns. The middle part of the lateral meniscus is loosely fused with the capsule. In the area of the transition of the horn to the lateral meniscus, the tendon of the popliteal muscle passes. In this place, the meniscus is separated from the capsule.

Normal menisci have a smooth surface and a thin sharp edge. Menisci badly blood. Vessels are localized in the anterior and posterior horns, as well as in the paracapsular zone, i.e. Closer to the capsule of the joint. Vessels penetrate the meniscus through the meniscocapsular junction and spread no more than 5-6 mm from the peripheral edge of the meniscus.

[1], [2]

Epidemiology of meniscal damage

Knee joint meniscus ruptures account for 60-85% of all closed knee joint injuries.

[3], [4],

Symptoms of meniscal damage

With incomplete longitudinal injuries of the horn of the medial meniscus, a visual examination does not reveal characteristic changes. In order to identify lesions, the upper and lower surfaces of the meniscus are examined using an arthroscopic hook. If there is a gap in the thickness of the meniscus, the tip of the probe fails. With a patchwork rupture of the meniscus, the flap may fold into the posterior medial section or into the medial flank, or flex under the meniscus. In this case, the edge of the meniscus looks thickened or rounded. If the meniscus body is injured at the site of the transition to the horn, it is possible to reveal the pathological mobility of the meniscus while pulling the hook located in the paracapsular zone. When the meniscus ruptures by the "handle of the watering can" type, the central detached part may be impaired between the condyles or significantly displaced. In this case, the peripheral rupture zone looks narrow and has a vertical or oblique edge.

Degenerative changes in the meniscus occur as a result of age-related changes. They are manifested in the form of tissue disintegration and softening and are combined with a violation of the integrity of the articular cartilage. With chronic long-term degeneration of the meniscus, its tissue has a dull, yellowish hue, and the free edge of the meniscus is disfigured. The degenerative breaks of the meniscus may not have clinical symptoms. Degenerative ruptures, as well as horizontal bundles of menisci, are often encountered in combination with oblique or patchy rills. For the discoid form of the lateral meniscus, an unusually wide margin is characteristic. If the meniscus completely covers the lateral condyle of the tibia, it can be mistaken for the articular surface of the tibia. The use of an arthroscopic hook makes it possible to distinguish a meniscus from the hyaline cartilage covering the tibia. Unlike articular cartilage, when the probe slides over the surface of the meniscus, it wavers in a waveform.

Classification of meniscal damage

There are different classifications of meniscus ruptures. The main meniscus lesions are as follows: rupture of the anterior horn, transverse or radial, complete or partial rupture of the meniscus body, longitudinal patchwork rupture, longitudinal rupture of the "handle of the watering can", paracapsular rupture, tearing of the horn, horizontal rupture.

Damage to the lateral and medial menisci is similar in many respects, at the same time longitudinal and patchwork are more typical for the medial meniscus, and for the lateral - horizontal and transverse ruptures. Damage to the medial meniscus is 3-4 times more often than the lateral one. Often simultaneously, both meniscus are broken, but the clinical manifestations of damage to one of them predominate. The overwhelming number of gaps occur on the horn of the meniscus. In this place, as a rule, an oblique or patchwork gap occurs. On the second place in frequency there is a longitudinal rupture of a meniscus. With a shifting meniscus, a long longitudinal rupture can turn into a "handle of the watering can" rupture. In the posterior horn of the inner meniscus, a horizontal splitting gap is often encountered in patients aged 30-40 years. All these discontinuities can be combined with oblique or patchy breaks. In the lateral meniscus, transverse (radial) ruptures are more common. The severed part of the meniscus, while maintaining a connection with the anterior or posterior horn, is often displaced and contracted between the condyles of the thigh and lower leg, causing blockade of the joint, which manifests itself by sudden restrictions of movement (extension), acute pain, synovitis.

[5], [6], [7]

Diagnosis of meniscal damage

Diagnosis of meniscus damage is based on the following symptoms.

• Symptom of Baikov. When you press your finger in the area of the joint slit with a shin bent to 90 °, a considerable pain appears in the knee joint. With prolongation of pressure and extension of the tibia, the pain increases because the meniscus rests against the immobile tissue immobilized by the finger. When flexing the meniscus shifts to the rear, the pressure decreases, the pain passes.
• Symptom of Chaklin. If the internal meniscus is damaged, the tonus decreases and the medial head of the quadriceps muscle of the thigh is hypotrophy. With the tension of the hip muscles against the background of the hypotrophy of the medial head of the quadriceps muscle of the thigh, one can observe the distinct tension of t. Sartorius.
• Symptom Apley. Pain in the knee joint with rotation of the tibia and flexion in the joint to 90 °.
• A symptom of Land, or a symptom of the "palm". The patient can not completely straighten the aching leg in the knee joint. As a result, a "lumen" is formed between the knee joint and the plane of the couch, which is not on the healthy side.
• Symptom of Perelman, or a symptom of a "ladder". Pain in the knee joint and uncertainty when descending the stairs.
• Symptom Steimann. Appearance of sharp soreness from the inside of the knee joint with external rotation of the tibia, with flexion of the shin the pain shifts backward.
• Symptom Bragarda. Pain in the inner rotation of the shin and irradiation it to the back with continuing bending.
• Symptom McMurray. With significant flexion in the knee joint, rotation of the shin (inside or outside) and its gradual extension, pain occurs in the corresponding part of the knee joint.
• A symptom of a "clue", or a symptom of Krasnov. Feeling of fear and uncertainty when walking, feeling in the joint of an alien, interfering object.
• Trader's symptom. Hypescension or anesthesia of the skin on the inner surface of the knee joint.
• Symptom of Beler. If the meniscus is damaged, walking back reinforces the pain in the joint.
• A symptom of Dedushkin-Vovchenko. The extension of the tibia with simultaneous pressure by the fingers to the projection of the lateral or medial condyle in front causes pain on the side of the lesion.
• Symptom to Merke. Serves for differential diagnosis of damage to the medial and lateral menisci. The patient, standing, slightly bends his legs in the knee joints and turns the body alternately in one direction or the other. The appearance of pain in the knee joint when turning inside (in relation to the diseased leg) indicates a damage to the medial meniscus, but if the pain appears when turning outward - about the damage of the lateral.
• Gaidukov's symptom. Presence of fluid in the knee joint. A more accurate transmission of transverse tremors in the area of the upper curvature with maximum flexion of the tibia (in comparison with the intact joint).
• The symptom of Payra. Pressing on the knee joint in the position of the patient with crossed legs causes severe pain.
• Symptom of Rauber. With chronic damage to the meniscus, an exostosis occurs at the upper edge of the pubic bone.
• Symptom of Hadzhistamov. With maximum flexion of the tibia in the knee joint and compression of the twists, the fluid in the cavity moves to the anterior part of the joint and forms small protrusions on the sides of the patellar ligament.

[8], [9], [10],

Treatment of meniscal damage

According to W. Hackenbruch, over the past 15 years, arthroscopic meniscectomy has become the "gold standard" for the treatment of meniscus lesions. Arthroscopy can detect, pinpoint and classify the type of meniscus damage. Low invasiveness of arthroscopic intervention led to the fact that the duration of stay of the patient in the hospital was significantly reduced in comparison with the open surgery. Previously practiced open meniscaectomy allowed only the removal of a part of the meniscus. The current endoscopic procedure makes it possible to perform a partial meniscectomy, i.e. Resect only the damaged part of the meniscus with the help of special tools while preserving the functionally important edge of the meniscus, which is necessary for normal biomechanics of the joint and maintaining its stability, which prevents the development of arthrosis.

In young patients in an acute period of trauma, arthroscopy allowed meniscus stitching. To perform the suture of the meniscus, the most important factor is the localization of its damage. The ruptures of the peripheral parts of the meniscus located in the blood supply zone heal better than the ruptures of the central regions where the avascular zone is located.

Arthroscopy allowed us to review the start and duration of rehabilitation in the postoperative period. After arthroscopy, an early load on the limb, early development of joint movements, and an early return to professional activity are possible.