Medial Meniscus Tear

🦵 Medial Meniscus Tear: A Comprehensive Overview for Physiotherapy Practice

Introduction

The medial meniscus is a C-shaped cartilage structure located on the inner side of the knee joint. It plays a vital role in load distribution, shock absorption, and joint stability. Injuries to the medial meniscus are prevalent, particularly among athletes and active individuals. Understanding the etiology, classification, clinical presentation, and management strategies for medial meniscus tears is crucial for effective rehabilitation and patient outcomes.

Definition

  • Anatomy & Function: The medial meniscus is a crescent-shaped fibrocartilage disc situated between the femur and tibia on the inner side of the knee. It functions to absorb compressive forces, stabilize the knee joint, and facilitate smooth movement by distributing weight evenly across the joint surfaces. 

  • Injury Overview: A medial meniscus tear refers to a disruption in the integrity of this cartilage, which can range from minor fraying to complete rupture. Such tears can compromise knee function and may lead to long-term joint degeneration if not appropriately managed. 

Cause

  • Traumatic Events: Sudden twisting motions, especially when the foot is planted and the knee is flexed, are common mechanisms leading to medial meniscus tears. 

  • Degenerative Changes: In older populations, degenerative processes can weaken the meniscal tissue, making it more susceptible to tears even with minimal trauma. 

  • Sports-Related Injuries: Athletes engaging in high-impact or pivoting sports, such as football, basketball, and soccer, are at increased risk due to the dynamic forces exerted on the knee joint. 

Classification

  • By Tear Pattern:

    • Longitudinal (Vertical): Tears that run parallel to the length of the meniscus; often associated with bucket handle tears.

    • Radial: Tears that extend from the inner edge toward the outer edge, resembling spokes on a wheel.

    • Horizontal: Tears that split the meniscus into top and bottom layers, commonly seen in older adults. 

    • Complex: Combination of multiple tear patterns, leading to irregular and unstable fragments.

  • By Location:

    • Red Zone: Outer third of the meniscus with a good blood supply, favorable for healing.

    • White Zone: Inner two-thirds with limited blood supply, where healing potential is poor. 

  • By Severity:

    • Grade I: Minor fraying or degeneration without significant disruption.

    • Grade II: Partial thickness tear extending into the meniscal tissue.

    • Grade III: Full-thickness tear extending through the entire meniscus. 

Signs and Symptoms

  • Pain: Localized to the medial (inner) side of the knee, often exacerbated by twisting motions or deep knee bends. 

  • Swelling: Gradual onset of swelling within 24-48 hours post-injury, indicating inflammation. 

  • Stiffness: Reduced range of motion, particularly in knee flexion and extension. 

  • Locking or Catching Sensation: Episodes where the knee feels as if it is "stuck," often due to displaced meniscal fragments. 

  • Instability: A sense of the knee giving way, especially during weight-bearing activities. 

Conclusion

Medial meniscus tears are significant knee injuries that can impact an individual's mobility and quality of life. Early and accurate diagnosis, coupled with appropriate treatment strategies—ranging from conservative management to surgical intervention—are essential for optimal recovery. Rehabilitation focusing on restoring strength, stability, and function is paramount in preventing long-term complications such as osteoarthritis.