The menisci are fibrocartilaginous structures that rest on the tibial plates inside the knee joint. There are two meniscus in each knee, one in an internal position, with a C shape, and another in an external position, with an O shape.
Its function is to help protect the joint surfaces during joint movement as well as to support the rotation of the knee. The irrigation of the meniscus only reaches the outer 1/3 of them, therefore, they will be the area in which the lesions will heal properly, this healing process being deficient in the 2/3 inmates, to which they do not reach terminations blood and are nourished through synovial fluid.
Characteristically, acute meniscal injuries are common in young patients who practice sports assiduously. Chronic meniscal lesions of degenerative origin appear from the second decade of life and progress faster under conditions of stress or intense overload of these. There are factors that increase the progression of the meniscal injury, such as the weakness of the surrounding musculature, the greater laxity of the knee ligaments or obesity, since they will increase the load on the meniscus, this being weakened with the passage of time. The medial meniscus injury is 3 times more common than the lateral meniscus injury.
Meniscal injuries are classified according to the direction the injury takes:
– Longitudinal injuries: they constitute 2/3 of the injuries. Lesions that run down the meniscus from anterior to posterior are called bucket handle lesions.
-Transversal sessions: are infrequent.
-Transversal lesions with loss of continuity are associated with degenerative pathology and chondropathies.
In most cases they respond to a twisting mechanism of the knee with the foot fixed on the ground in greater or lesser degrees of flexion. In older patients with a degenerative lesion of the meniscus, a simpler movement such as sitting or bending over can trigger a break. When the knee flexes, both menisci tend to move towards the center of the knee and, when extended, recover their position. If there is a meniscal injury, when flexed, the injured area moves to the center of the joint and when the knee is extended with force, that fragment tends to get trapped, causing the clinical blockage that usually accompanies the meniscal lesions.
Exploration and clinical history:
It is necessary an adequate clinical history in which the mechanisms of production are related as well as an exploration that supports the suspicion: – Pain in the joint line when pressing on the meniscus.
-Derrame articulate: An immediate and intense spill just after the injury is more indicative of ligament injury or fracture. The effusion of the meniscal lesion begins to manifest itself later. In case of meniscal injury of a degenerated meniscus, joint effusion will not occur.
-Block of the knee: It appears well as a result of the joint effusion that increases the pressure inside the joint and therefore the contracture of the muscles tries to protect the knee from the movements that could increase even more the pressure of liquid in the Within the joint and producing pain, the joint usually appears in a semiflexion position, in which the intra-articular pressure is lower. On other occasions, the blockage may be due to the interposition of the injured meniscus fragments inside the joint. -Maniscal exploration maneuvers: Consisting of a series of movements of the knee causing pain to be triggered by adopting a certain position:
1) McMurray test: The patient lying in the supine position, knee and hip flexed, rotating the leg externally while maintaining that position.
2) Apley test: In the prone position, with the knee flexed, the leg is extended while it is externally rotated.
Diagnosis of image: Simple knee radiography: It does not provide information, it only serves to rule out the existence of a bone lesion or associated fracture.
Nuclear magnetic resonance: Given a clinical suspicion, it constitutes the most sensitive imaging test for its diagnosis.
In the absence of recurrent inflammatory signs, joint blockages or complications, and especially if they are degenerative, they will be treated conservatively.
In younger patients with mechanical repercussions and in those in whom conservative treatment fails, more aggressive measures are taken. Arthroscopic surgery is the technique of choice for the treatment of meniscal lesions. The indications of the same are defined by the specialist doctor in function of the findings and the alteration of the daily life that supposes to the patient.
The technique used in arthroscopic surgery depends on intraoperative findings