Rosemont, Ill. - The meniscus is a rubber-like, crescent moon-shaped cartilage cushion that sits between the leg and thigh bone. Each knee has two menisci: one on the inside of the knee joint and one on the outside. In recent years, more children have been diagnosed with tears to this area (meniscal tears); however, according to a literature review published in the November 2009 issue of the Journal of the American Academy of Orthopaedic Surgeons (JAAOS), prospects for a full recovery are high.
"Seventy-five to 90 percent of children who have meniscal tears heal successfully when they are treated appropriately. In adults, the success rate is often less than 50 percent," said study co-author Dennis Kramer, M.D., an attending orthopaedic surgeon at Children's Hospital Boston and instructor in Orthopaedic Surgery at Harvard Medical School. "A child's physiology is different than an adult's--they are growing and therefore have a greater blood flow to the meniscus. This helps in the healing process."
How Meniscal Tears Occur
Meniscal tears often occur when a child twists his or her knee while playing sports (the area becomes painful and swollen and tears are sometimes dismissed as knee sprains). Children can continue to experience pain, but often do not seek help because they do not want to miss out on sporting events or have to go to the doctor.
Additionally, a small percentage of children are born with abnormally shaped "discoid" menisci that are larger and therefore more prone to tearing. If your child complains of a "snapping" or "popping" knee, it may be due to a discoid meniscus.
According to the study, several factors are contributing to the increase in diagnosis of meniscal tears in children:
- more children are participating in sports, where knee injuries often occur;
- more healthcare professionals are aware of and recognize the signs of meniscal tears; and
- the use of magnetic resonance imaging (MRI) helps physicians to better diagnose them.
Early Treatment Important for Long-Term Health
Dr. Kramer stresses that although meniscal tears in children can often be repaired successfully, they should be treated quickly.
"Tears that are repaired within three months seem to heal better than those treated at a later time," he said. "Additionally, if a child has a meniscal tear that cannot be repaired but instead has to be removed, studies indicate that it can lead to arthritis later in life."
Diagnosing and Treating a Tear in a Child
If you believe your child has a meniscal tear, visit your doctor. Dr. Kramer suggests parents may expect the following:
- The doctor will conduct a simple physical. Your child will be asked to bend and twist the leg in a certain way to cause stress to the meniscus, as well as push on the area of the knee where the meniscus is located to determine if it is injured.
- The doctor will attempt to perform the exam to minimize any pain. Ask if your physician knows how to make these modifications. If he or she is not comfortable making this assessment, you may want to visit an orthopaedic surgeon or physician who specializes in sports medicine who has experience conducting these tests.
- If the physical tests indicate there is a tear, your doctor may schedule an MRI. Dr. Kramer notes that pediatricians, radiologists or physicians specializing in sports medicine may be better equipped to interpret the results of your child's MRI.
- If the MRI indicates that your child has a meniscal tear, your child may need arthroscopic surgery. This is a minimally invasive surgical technique using small incisions and tiny pencil-sized instruments that contain a small lens and lighting system to magnify and illuminate the structures inside the knee.
Smaller Injuries Can Progress, So Talk to Your Doctor
"Smaller injuries can progress and get worse if left untreated, said Dr. Kramer. "If you suspect your child has a meniscal tear, talk to your doctor and discuss treatment options as soon as possible."
Disclosure: Dennis E. Kramer, M.D., is an Instructor, Department of Orthopaedic Surgery, Children's Hospital Boston, Boston, MA. Lyle J. Micheli, M.D., co-author of the study, is Director of Sports Medicine, Department of Orthopaedic Surgery, Children's Hospital Boston. Dr. Micheli or a member of his immediate family is affiliated with the publications BMC Musculoskeletal Disorders and the Journal of Bone and Joint Surgery. Neither Dr. Kramer nor a member of his immediate family has received anything of value from or holds stock in a commercial company or institution related directly or indirectly to the subject of this article.