Sprains & Strains

Here are some facts on musculoskeletal injuries:

• Sprains are a stretch and/or tear of a ligament, the tissue connecting two bones. Ligaments stabilize and support the body's joints. For example, ligaments in the knee connect the upper leg with the lower leg, enabling people to walk and run.

• Strains are a twist, pull and/or tear of a muscle and/or tendon. Tendons are cords of tissue that connect muscles to bones.

• Breaks are a fracture, splinter or complete break in bone, often caused by accidents, sports injuries or bone weakness.

Health care providers attend to millions of Americans with musculoskeletal injuries each year, according to the United States Bone and Joint Decade (USBJD). The USBJD reported that there were approximately 18.4 million sprains and strains treated, and about 16.2 million fractures treated in 2007 in the United States.

Sprains

A sprain is caused by trauma — a fall, twist, or blow to the body, for example — that applies stress to a joint and overstretches or even ruptures supporting ligaments.

In a mild sprain, a ligament is stretched, but the joint remains stable and is not loosened. A moderate sprain partially tears the ligament, producing joint instability. With a severe sprain, ligaments tear completely or separate from the bone. This loosening interferes with joint function. You may feel a tear or pop in the joint. Although the intensity varies, all sprains commonly produce pain, swelling, bruising, and inflammation.

The ankle is the most commonly sprained joint, and a sprained ankle is more likely if you've had a previous sprain there. Repeated sprains can lead to ankle arthritis, a loose ankle or tendon injury.

Strains

Acute strains are caused by stretching or pulling a muscle or tendon. Chronic strains are the result of overuse of muscles and tendons, through prolonged, repetitive movement. Inadequate rest during intense training can cause a strain.

Typical symptoms of strain include pain, muscle spasm, muscle weakness, swelling, inflammation and cramping. In severe strains, the muscle and/or tendon is partially or completely ruptured, resulting in serious injury. Some muscle function will be lost with a moderate strain, in which the muscle/tendon is overstretched and slightly torn. With a mild strain, the muscle or tendon is stretched or pulled, slightly.

These are some common strains:

• Back strain. When the muscles that support the spine are twisted, pulled or torn. Athletes who engage in excessive jumping — during basketball or volleyball, for example — are vulnerable to this injury.

• Hamstring muscle strain. A tear or stretch of a major muscle in the back of the thigh. The injury can sideline a person for up to 6 months. The likely cause is muscle strength imbalance between the hamstrings and the quadriceps, the muscles in the front of the thigh. Kicking a football, running or leaping to make a basket can pull a hamstring. Hamstring injuries tend to recur.

Treating injuries

A severe sprain or strain may require surgery or immobilization, followed by physical therapy. Mild sprains and strains may require rehabilitation exercises and a change in activity during recovery. In all but mild cases, your health care provider should evaluate the injury and establish a treatment and rehabilitation plan. Meanwhile, rest, ice, compression and elevation (called RICE) usually will help minimize damage caused by sprains and strains.