Knee Pain, Meniscus tear symptoms, diagnosis, and treatment. скачать в хорошем качестве

Knee Pain, Meniscus tear symptoms, diagnosis, and treatment.

There are two menisci. The lateral meniscus is circular and covers approximately 70% of the lateral tibial plateau. The medial meniscus is C-shaped and covers approximately 50% of the medial tibial plateau. The lateral meniscus is more mobile, while medial meniscal tears occur approximately three times more often than lateral meniscal tears. The primary functions of the meniscus are shock absorption, load distribution, and providing joint stability. Causes of meniscal tears include twisting, jumping, or sudden directional changes, particularly common during sports or skiing. Tears may also be degenerative, especially in older populations, and can occur in association with arthritis. Symptoms typically include pain on the medial or lateral side of the knee, accompanied by mechanical symptoms such as locking, clicking, and swelling. Upon examination, joint line tenderness is the most sensitive finding. Patients may also experience posterior knee pain. Effusion may be present, although it can be difficult to detect initially, sometimes taking several hours to develop following injury. In contrast, an ACL tear typically results in rapid-onset hemarthrosis due to significant bleeding. The diagnostic test commonly used is the McMurray test. A painful pop or click is elicited as the knee moves from flexion to extension with internal or external rotation. To perform the test for medial meniscal tear, flex the knee, place your hand on the medial side of the knee, externally rotate the leg, and then extend the knee. A palpable or audible pop or click with associated pain indicates a positive McMurray test for medial meniscal injury. Occasionally, examination questions may include an image of the lateral meniscus. How can you recognize it? Both the anterior and posterior horns of the lateral meniscus can be seen simultaneously because the lateral meniscus is circular. Conversely, due to the C-shaped nature of the medial meniscus, either the anterior or posterior horn can be visualized, but not both simultaneously in one view. Additionally, the presence of the popliteus tendon confirms that the structure is the lateral meniscus. If diagnosing or suspecting a lateral meniscal tear, the McMurray test should be performed with internal rotation. Sometimes the knee becomes locked, lacking full extension due to a bucket-handle tear. Differential diagnosis is important, as clinical accuracy for diagnosing meniscal tears alone is approximately 70%. MRI is frequently performed to confirm the diagnosis or identify additional intra-articular knee pathology. Differential diagnoses include intra-articular and extra-articular conditions. Intra-articular conditions include medial plica syndrome, osteochondritis dissecans (OCD), patellofemoral pain syndrome, or a loose body within the joint. Extra-articular conditions can include collateral ligament injury (particularly the medial collateral ligament), pes anserine bursitis, lumbar disc herniation, stress fractures, iliotibial band syndrome, or slipped capital femoral epiphysis (SCFE) in pediatric patients presenting with knee pain. Blood supply to the meniscus originates from the geniculate vessels and the peripheral capsular attachments. The peripheral one-third, known as the "red-red zone," is highly vascularized, and tears in this region generally heal well. If the tear occurs in the outer third—the red zone—it typically heals because of adequate vascularization. Tears in the middle third (red-white zone) may or may not heal, but healing is less predictable. Tears in the inner third (white zone) are avascular, and healing does not typically occur. Thus, peripheral tears in the outer 25% (red zone) heal by forming fibrocartilaginous scars, and peripheral tears measuring less than four millimeters have excellent healing potential. Generally, the smaller the rim width, the greater the potential for healing. Treatment of meniscal tears initially involves non-operative management, especially for small, non-displaced, and degenerative tears. Non-operative treatment includes physical therapy, NSAIDs, and potentially corticosteroid injections if symptoms persist. When conservative treatment fails, surgical intervention is considered. Surgical options include partial meniscectomy (excision of the tear) or meniscal repair. Partial meniscectomy is indicated for complex, degenerative, or radial tears that cannot be repaired. Surgeons generally minimize the amount of meniscus removed because the risk of arthritis correlates with the amount of meniscal tissue excised. Meniscal repair is generally reserved for peripheral tears with adequate vascular supply, ensuring better healing outcomes. Acute meniscal repair combined with ACL reconstruction is often preferred, although this approach remains a topic of debate.