The meniscus is a form of cartilage which is C-shaped and triangular in cross section and sits in between the femur and the tibia on the medial and lateral sides of the knee.  There are two menisci in the knee which differ slightly in their shape and biomechanics.  The main function is to protect the femur and tibial cartilage joint surfaces from the incredible amount of force and load that passes through the knee joint on a daily basis from walking to intense exercise.  The meniscus is attached to the top of the tibia via the anterior and posterior horns and through the capsular attachments circumferentially around the knee.  It is through the capsule that the meniscus receives a little blood supply to its periphery.  The outer one third of the meniscus has blood flow going through it but the inner two thirds of the meniscus is avascular and has no blood flow.  

What are the causes of Meniscal Injury?

The meniscus is prone to injury especially during twisting and turning sports.  As we get older the substance of the meniscus becomes less resilient and is prone to tearing and meniscal injuries represent one of the most common sporting injuries to the knee.  There are different types of meniscal tears and multiple classifications and descriptions of meniscal tears.  These can range from vertical, horizontal, bucket handle, parrot beak, complex and a whole host of other varieties.  Meniscal tears can form part of other more major injuries such as an ACL rupture. 

What are the symptoms of Meniscal Tear?

An isolated meniscal tear usually presents with a painful swelling in the knee after the match or competition may be over and presents with a swelling over the next few days.  There is pain in the knee as well as symptoms such as locking of the knee and a feeling of giving way or instability.  

What is a Meniscal Root Tear?

A meniscal root tear is a type of tear where the attachment of the meniscus at the back of the knee tears and the meniscus becomes detached at the root. This pathology has only been recognised in the last 5 to 10 years and techniques have been developed to repair the meniscal root.

 A meniscal root tear is a highly significant injury and it is imperative that it is assessed during any knee arthroscopy operation. Meniscal root tears can occur in isolation and quite often as part of an ACL rupture. If the route becomes detached, this results in a complete incompetence of the meniscus.

The meniscus can no longer perform its role properly and is no longer able to absorb and dissipate the forces being transmitted through the knee joint. It is the equivalent of having no meniscus on that side of the knee and therefore results in rapid progress of osteoarthritis within the knee joint.

 This is why it is imperative that root tears are assessed for, especially during ACL surgery and repaired appropriately thereby restoring the joint biomechanics.  If the router is missed during ACL reconstruction surgery, then this predisposes the patients to a further ACL rupture.

What is a Meniscal Ramp Lesion?

A ramp lesion is also known as a menisco-capsular dissociation. This is where the medial meniscus separates from the capsular lining at the back. This doesn’t appear as a true meniscal tear and to the untrained eye, looks like a healthy meniscus. These are often missed by non-specialist knee surgeons. They usually occur as part of the ACL rupture injury. If these are missed at the time of ACL reconstruction, then this results in an inherent instability in the knee and puts extra strain on the ACL reconstruction graft, and therefore predisposes to further injury and re-rupture.


What are the treatments for Meniscal Injuries?

The treatment of a meniscal tear depends on a number of factors.  It depends on: 

  • the age of the patient
  • level of activity
  • type of tear
  • severity of symptoms that a patient presents with

The most worrying symptoms in meniscal injury are locking and giving way of the knee and in any age group these symptoms are usually best addressed with meniscal surgery.  If a patient presents only with pain and no symptoms of locking or giving way, then a trial of conservative therapy for at least three months with physiotherapy is first indicated.  If pain continues for more than three months then a further discussion would be required around the best form of treatment which may be meniscal surgery.