Last reviewed by Dr. Raj MD on January 12th, 2022.
What is a Torn Meniscus?
A torn meniscus is one of the most common reasons for knee injury which involves the menisci of the knee. Torn meniscus is characterized by a rupture in one or more of the menisci of the knee often as a result of injury to the knee.
The knee is the largest of the joint found in the human body and each knee consist of two menisci. Each menisci act as a cushion to the knee primarily as a shock absorber. The meniscal tear is regarded as the most common knee injury and often in individuals involved in contact sports, although almost anyone is actually potential for a meniscal tear.
The knee is a complex joint that is often used in everyday movement making it susceptible to injury. The knee is an important part of the body that allows movement from one place to another such as walking, jumping and running including bending and flexing. The knee joint facilitates the movement and this largest joint in the human body is made up of three bones called the femur, tibia and the patella. In between the femur and the tibia lies a rubbery and C-shaped disc called menisci which function as a shock absorber and keep the knee stable by distributing a balance weight on the knee. A tear in the meniscus can cause the knee to fail to function properly. A torn meniscus generally causes swelling and pain which can result to discomfort and affect the normal movement.
Torn Meniscus Symptoms
The symptoms of a torn meniscus vary and generally differ from one patient to another. A patient may feel pain and discomfort while another patient may not feel any discomfort. The symptoms depend on the severity and cause of the meniscal tear.
A torn meniscus however, commonly results in swelling regardless of the type of meniscal tear and its severity. Any form of injury usually result to inflammatory response and thus the symptom of pain and swelling which are common in torn meniscus. The symptom of pain may develop later in some patient particularly those with mild tear in the meniscus.
The symptoms of pain and swelling may also be associated with other symptoms such as:
- Pain when walking, running and jumping or in moving about
- Pain with flexion and extension of the knee
- Feeling of tightness over the affected knee
- Sporadic swelling of the affected knee joint
- Feeling of knee instability and a feeling of falling down
- Popping sensation especially when climbing or going down the stairs
- Inability to move and fully extend the knee or the so called locking particularly in severe trauma where fragments of torn meniscus folds in and mechanically blocks the knee joint
The incidence of a torn meniscus may come in varying degrees which can be mild, moderate and severe. The pain and swelling in mild cases of torn meniscus is usually slight in severity and usually resolves over the period of 2 to 3 weeks.
The torn meniscus in moderate severity commonly causes pain at the core of the knee and with swelling that usually gets worse in a span of 2 to 3 days. The knee will generally feel stiff and bending of the knee is limited although walking is still possible. The symptoms in moderate meniscal tear usually resolve in a week or in 2 weeks although recurrence is highly potential particularly when there is overuse and accidental twisting of the knee.
A popping sensation and lock of the knee joint is common in severe case of the torn meniscus. The symptoms of popping and lock are the result of fragments of meniscal tear that get lodged in the joint space. The lock of knee joint results to limited flexion of the knee joint and a limited extension as well. Pain is a common symptom while swelling and stiffness of the knee joint usually develop over the period of 2 to 3 days following injury.
Meniscus tear is composed of various types which are identified according to the size and shape of the tear.
Radial meniscus tears are characterized as short tears that expand to the periphery of the meniscus from the inner margin and the head of the meniscus. This type of tear is usually located on the medial aspect of the lateral meniscus.
Horizontal meniscus tear is the most common type of tear that cuts the meniscus in half nearly making a two C-shaped disc.
Bucket handle tear is the biggest among the meniscus tear. The tear is characterized by a C-shaped disc that flips over the front of the knee. It is a vertical longitudinal tear associated with a displacement of the inner margin of the meniscus. This type of tear can also result to lock knee which can cause a limited flexion and extension of the knee joint.
Torn Meniscus Causes
The incidence of tear in the meniscus can be due to various reasons and injury to the knee joint involving the meniscus is the primary implicated in the meniscal tear. It is important to identify the cause of a torn meniscus as this will determine the type of treatment needed whether the tear will have to be stitched or removal of fragments is necessary.
The cause of the torn meniscus can be classified as:
Acute or traumatic meniscus tear is the result of an injury. Activities that cause a forceful impact or movement such as twisting and aggressive rotating of the knee can result to a tear in the meniscus. Repetitive movement of the knee, sudden pivoting and lifting of heavy objects are among the causes of acute meniscus tear. Athletes or individuals involved in contact sports are often seen with a torn meniscus as a result of high impact activities that can injure the knee joint.
Degenerative meniscus tear is not directly caused by an injury or trauma to the knee joint and its meniscus. It is the type of meniscus tear that resulted from the natural and normal wear and tear of bone density usually from age advancement or is part of the normal aging process. It is normal and natural for the cartilage and bone joints to weaken overtime thus potential for a meniscal tear. The brittle characteristic of bones in older patients makes them more susceptible to a meniscal tear even with a simple twist from getting up coming from a sitting position.
The treatment of torn meniscus depends on the type of tear and the severity. The goal of treatment is to relieve the symptoms and to restore the function, range of motion and strength of the knee. Nonsurgical treatment is usually required in mild meniscus tear including moderate meniscus tear. Surgical intervention is indicated for severe meniscus tears particularly those with large tear and with dislodgement of fragments of meniscus.
Arthroscopic surgery is the primary form of treatment for severe meniscal tear and when the patient remains unresponsive despite application of conservative treatment. Arthroscopic surgery utilizes an arthroscope which contains a camera while an incision instrument can be inserted through the arthroscope. The meniscal tear can either be repaired or removed depending on the extent or degree of tear.
The arthroscopic surgery for meniscal tear usually takes an hour to perform and patients are often sent home the same day right after the effect of anesthesia has subsided or when the patient is more comfortable to move. The recovery time however depends on the type of surgery performed and if no medical complications exist following surgery.
Recovery time for arthroscopic surgery on the other hand is much faster and full recovery may take several weeks or months. Several factors however are considered in determining how fast full recovery may take place. Such factors include the age, weight, activity and overall health status of the patient. Movement of the knee is encouraged following surgery to promote speedy recovery and to prevent muscle atrophy.