What is a meniscus?
The meniscus is a tough, smooth, rubbery C-shaped piece of cartilage (fibrocartilage) that is wedged shaped and sits between the cartilage surfaces of the bones. It distributes your body weight more evenly across the knee joint and improves the stability of the joint. Each knee has two menisci, the medial (inside) and the lateral (outside). They attach to the top of the shin bone (tibia) and make contact with the thigh bone (femur). They act as shock absorbers during weight-bearing activities.
- The front ⅓ is called the “anterior horn”.
- The middle ⅓ is called the “body”.
- The back ⅓ is called the “posterior horn”.
The wedged shaped profile helps maintain the stability of the joint by keeping the rounded femur surface from sliding off the flat tibial surface. The meniscus is nourished by small blood vessels coming in from the outer edges (vascular zone). The meniscus also has a large area in the inner ⅓ that has no direct blood supply (avascular zone). Between these zones is an area where the blood supply is minimal.
What is a torn meniscus?
A torn meniscus occurs when the meniscus develops structural damage from an acute traumatic event or repetitive microtraumatic events. Tears can occur in different parts of the meniscus and with different tear patterns. Tears are commonly described as radial, transverse, horizontal, flap, bucket handle, macerated, root, and intrasubstance tears. When there is an injury to the meniscus in the avascular areas, these tears tend not to heal. Some tears in the vascular zone have the potential to heal, sometimes. Some tears cause significant pain and symptoms, while other small tears sometimes go unrecognized.
What are the symptoms of a meniscus tear?
The most common symptom of a meniscus tear is knee pain. The pain occurs from several different activities including twisting, squatting, rising and sitting, and with pressure against your other knee when sleeping.
- Knee Swelling is common with a meniscus tear.
- Tenderness at the joint line when pressing on the meniscus.
- Popping or Clicking sensations can be felt when bending the knee, walking, running, lunging, stair climbing, or twisting.
- Reduced motion of the knee with the inability to fully straighten or fully bend is a common complaint. Sometimes the knee gets stuck or locks in a position.
- Torn fragments of cartilage may catch in the joint, causing locking, catching, sudden giving away or sharp pain.
What are the causes of a torn meniscus?
People sometimes know exactly when they tore their meniscus, others have no recollection of a specific event that may have caused the tear. Tears can be from an acute event. These include:
- A sudden twist or turn of the knee, tripping and twisting the knee, squatting or twisting during an aerobic exercise class, getting tackled in a sports event.
- Tears can occur from several microtraumatic events that culminate in structural integrity loss and an eventual tear of the meniscus.
- Tears can occur from a degenerative condition of the knee bone surface cartilage like osteoarthritis, that causes mechanical damage and tearing of the meniscus.
What makes someone a meniscus tear specialist?
A meniscus tear specialist is an orthopaedic surgeon who specializes in the knee, and is trained in knee arthroscopy and techniques to manage and treat tears. A specialist should know when not to operate and treat tears no-surgically, and when tears require surgical intervention. A specialist knows how to repair or remove parts of tears based on their structural findings during surgery.
Can you leave a meniscus tear untreated?
Some tears that are asymptomatic and small can be left alone and treated without surgery initially. This may include a temporary knee brace and rehabilitation to keep the knee muscles strong while the knee is not bearing as much weight. This approach is most effective for small tears (5 millimeters or less) that are minimally symptomatic. Taking orally or injecting anti-inflammatories to reduce swelling can be done if surgery is not an option or if surgery is not wanted by the patient. Larger tears and painful tears are commonly treated arthroscopically due to the irritating symptoms that make the patient uncomfortable with activities of daily living, sports activities and difficulty with sleeping without pain.
How do you repair a meniscus tear?
A meniscus tear can be surgically treated by either partial meniscectomy or meniscus repair. A Partial Meniscectomy is a surgery to remove the part of the meniscus that is torn. If the tear involves a part of the meniscus where healing is poor or the tear is not in a location or of a type that can be repaired, the surgeon will trim away the torn or ragged edges of the tear to allow the joint to move smoothly again. The recovery after partial meniscectomy is typically 2 to 8 weeks if the rest of the joint is in good condition. A Meniscal Repair is a surgery to repair the tear with stitches if the tear is in the vascularized zone, and in the correct orientation. It can take 3 to 6 months for a repaired meniscus to heal. Most surgeons would like to repair tears if possible to maintain as much cushion for the knee as possible, however, most tears are no of the repairable type and require partial meniscectomy.
What is a Knee Arthroscopy?
Knee Arthroscopy is a procedure in which the doctor examines your knee with an instrument called an arthroscope to diagnose or treat the cause of pain, swelling, tenderness, or weakness in your knee. An arthroscope is a tube with a camera and light at its end that projects an image of the inside of your knee onto a television monitor. The arthroscope is about the diameter of a pencil.
The surgeon will put an arthroscope and one or two tools into the knee joint through small incisions (cuts). Fluid is injected into the knee to expand the joint so that the structures and cartilage can be seen on the monitor. The surgeon will examine the knee to find any damage. He may repair torn cartilage, or shave down the cartilage in the knee, and/or remove pieces of cartilage. The arthroscope and tools are then removed, and the incisions are closed with stitches.
What is a Knee Chondroplasty?
An Arthroscopic Chondroplasty is a procedure in which the worn or damaged articular cartilage surfaces are trimmed and smoothed of their degenerated edges in arthritic knees, while debris is removed with suction shaving devices.
What is a Knee Synovectomy?
An arthroscopic synovectomy is the removal of inflamed inner lining tissues of the knee joint (the synovium) that is abnormally growing, and can cause swelling and pain in the knee.