Medial meniscus injury

The knee contains two crescent shaped pieces of cartilage that attach on top on the tibia (shin bone), one on the medial (inner) aspect and the other on the lateral (outer aspect). These menisci function to

Create an enhanced fit between the femur (thigh) and (tibia) shin bone
Act as shock absorbers
Improve the flow of synovial fluid (joint lubricant) within the joint capsule
Transmit force between tibia and femur

The medial meniscus is more prone to injury than the lateral as it is more firmly attached to the adjacent structures and can therefore not ‘get out of the way’ in the event of a sudden forceful impact. The classic mode of injury occurs when the knee rotates forcefully whilst weightbearing. The menisci may get injured in conjunction with the anterior cruciate ligament. Injury to the meniscus typically progress as follows

Immediate pain with difficulty in fully extending (straightening) leg
Swelling appears within 24-48 hours
Symptoms resolve within 2 weeks
Recurrent mini episodes following the above sequence of events precipitated when the knee gives way whilst twisting

Meniscal damage can also result from wear and tear as we get older causing the cartilage to become rough and frayed – more common in middle and old age.

Symptoms

Pain on the medial (inner) aspect of the joint
Swelling (possibly warm) all around knee joint
Reduced range of flexion (bending) possibly limited to 90 degrees
Inability to fully straighten knee
Clicking noise (crepitus)
Knee giving way
Pain aggravated by weight bearing
Pain aggravated by walking on uneven surfaces as knee cannot fully straighten and becomes unstable