ATHLETIC EDGE
Sports Medicine
Sports Injury Prevention & Rehabilitation
 540 BRYANT ST, PALO ALTO, CA 94301
(650) 815-6552

Voted Best Sports Therapy Clinic in the San Francisco Bay Area 2010-2016!

Lateral Meniscus Tear

(Also known as a Lateral Meniscal Tear, Torn Lateral Meniscus, Lateral Cartilage Tear, Lateral Meniscal Dysfunction, Bucket Handle Tear of the Lateral Meniscus, Torn Meniscus, Torn Cartilage)
 
What is a lateral meniscus tear?
The knee joint comprises of the union of two bones: the long bone of the thigh (femur) and the shin bone (tibia). Between the bone ends are two round discs made of cartilage called the medial (inner) and lateral (outer) meniscus . Each meniscus acts as a shock absorber cushioning the impact of the femur on the tibia during weight-bearing activity. Normally the surface of the meniscus is very smooth allowing easy movement of the femur on the tibia. Occasionally the meniscus can be torn or damaged so that the surface is no longer smooth. When this occurs to the lateral meniscus, it is known as a lateral meniscus tear. Injuries to the lateral meniscus are less common than medial meniscus injuries.
Lateral meniscal tears can occur suddenly due to too much weight bearing or twisting force going through the meniscus beyond what it can withstand, or gradually due to repetitive or prolonged weight bearing or twisting forces.
Injuries to the lateral meniscus occasionally occur in combination with injuries to other structures of the knee, such as the cruciate ligaments, the collateral ligaments, or the medial meniscus.

Causes of a lateral meniscus tear
Lateral meniscus tears often occur traumatically in sports that require sudden changes of direction and twisting movements (sometimes in combination with excessive straightening or bending of the knee). These sports may include football, soccer, basketball, tennis and snow skiing. Lateral meniscal tears frequently take place when the foot is fixed on the ground and a twisting force is applied to the knee (e.g. when another player's body falls across the leg, or when a player is tackled) or following a forceful jump or landing.
Lateral meniscal tears may also occur over time through gradual wear and tear (e.g. excessive distance running). This may be associated with degenerative changes to the knee joint. In older patients where degenerative changes are present, injury to the lateral meniscus may occur with a relatively trivial movement.

Signs and symptoms of a lateral meniscus tear
Patients with a lateral meniscal tear may report that they heard an audible sound at the time of injury or experienced a tearing sensation. There is usually pain with weight bearing activity and twisting movements of the knee. Patients may also experience pain when climbing stairs, attempting to kneel or when squatting. Swelling is often present in patients with lateral meniscal tears and may occur a few hours after injury or, more commonly, in the following days. It is usually tender to touch the joint on the outer aspect of the knee. The knee may also feel weak or unstable and may click or lock during certain movements.
In minor cases of lateral meniscus tears there may be little or no immediate symptoms. In these cases, symptoms may develop gradually over the coming days, typically with an increase in weight bearing or twisting activity. In more severe cases there may be severe pain and significant restriction in knee range of movement. Intermittent locking, clicking sensations, and episodes of giving way or collapsing may be present. The patient may also walk with a limp or, be unable to weight bear due to pain.

Diagnosis of a lateral meniscus tear
A thorough subjective and objective examination from a physician is usually sufficient to diagnose a lateral meniscus tear. Investigations such as X-ray and MRI are sometimes used to confirm diagnosis and exclude the presence of other injuries to the knee. In rare cases, where an MRI has proven inconclusive, an investigative arthroscope may be performed to assist diagnosis.

Treatment for a lateral meniscus tear
Most minor tears to the lateral meniscus heal well with appropriate physical therapy. The success rate of treatment is largely dictated by patient compliance. A vital aspect of treatment is that the patient rests sufficiently from twisting and weight bearing activities (such as standing, walking, lifting, squatting, and running etc) until they are pain-free. Once the patient can perform these activities pain free, a gradual return to these activities is indicated provided there is no increase in symptoms.
Patients with a lateral meniscus tear usually benefit from following RICE. RICE is beneficial in the initial phase of the injury (first 72 hours) or when inflammatory signs are present (i.e. morning pain or pain with rest). This involves resting from aggravating activities, regular icing, the use of a compression bandage and keeping the leg elevated. Anti-inflammatory medication may also significantly hasten the healing process by reducing the pain and swelling associated with inflammation.
Patients with a lateral meniscus tear should perform pain-free flexibility and strengthening exercises as part of their rehabilitation to ensure an optimal outcome. One of the key components of rehabilitation is pain-free strengthening of the quadriceps (vastus medialis obliquus muscle – VMO), hamstrings, calf and gluteals to improve the control of the knee joint with weight-bearing activities. The treating physical therapist can advise which exercises are most appropriate for the patient and when they should be commenced.

Surgery for a lateral meniscus tear
Despite appropriate physical therapy management, a small percentage of minor meniscal tears fail to improve and subsequently require surgery in order to get back to full activity. The majority of large meniscal tears also require surgery. This is particularly true in those cases where the knee is 'locked'. Surgery for lateral meniscus tears is minimally invasive. The procedure is called a knee arthroscope and involves a surgeon cutting away the torn part of the cartilage via two small incisions so that the meniscal surface is smooth once again. The aim of surgery is to preserve as much of the meniscus as possible. The treating physical therapist and doctor will refer to a specialist if surgery is indicated. Physical therapy and rehabilitation is then required following surgery to ensure an optimal outcome and enable a safe return to sport or activity.

Prognosis of a lateral meniscus tear
Those patients with minor lateral meniscus tears that are managed conservatively can usually expect to return to sport or activity in approximately 2 - 4 weeks. For moderate tears that are managed conservatively return to sport or activity may take 4 - 6 weeks or longer.
Minor lateral meniscus tears that are managed surgically can sometimes return to sport or activity within 4 – 6 weeks, although most surgical repairs (especially when the meniscus tear is moderate to severe) will usually require a rehabilitation period of 6 - 8 weeks or longer. If there is damage to other structures in the knee, such as the anterior cruciate ligament, rehabilitation may require an extended period.
It is important that lateral meniscus injuries are managed appropriately, as inappropriate treatment may lead to the development of early knee osteoarthritis.

Physical therapy for a lateral meniscus tear
Physical therapy treatment is vital to hasten the healing process and ensure an optimal outcome in all patients with lateral meniscus tears regardless of whether they have surgery.
Physical therapy treatment may comprise:
  • soft tissue massage
  • electrotherapy
  • taping or bracing to support the knee
  • mobilization
  • dry needling
  • hydrotherapy
  • the use of crutches
  • ice or heat treatment
  • progressive exercises to improve flexibility, balance and strength (especially the VMO muscle)
  • activity modification advice
  • education
  • biomechanical correction
  • anti-inflammatory advice
  • weight loss advice where appropriate
  • the use of Ultrasound to assess and retrain the VMO muscle
  • a gradual return to activity program
For those patients who are undergoing surgery to repair the torn meniscus, physical therapy and rehabilitation should commence prior to surgery. This may include treatment to reduce pain and swelling, electrotherapy, strengthening and range of movement exercises, the use of a compression bandage, and the use of crutches etc.
Following surgery, physical therapy and rehabilitation is essential to assist the healing process and ensure an optimal outcome. In the final stages of rehabilitation for all lateral meniscus tears the physiotherapist can devise an appropriate return to sport or activity plan. Returning to activity too soon or without adequate rehabilitation will often lead to knee swelling and re-injury to the meniscus.

Other intervention for a lateral meniscus tear
Despite appropriate physical therapy management, some patients with lateral meniscus tears fail to improve either conservatively or following surgery. When this occurs the treating physical therapist or doctor can advise on the best course of management. This may include further investigations, pharmaceutical intervention, corticosteroid injection, or further surgery.