Lecture 9

Injuries to the muscles, bones and joints include sprains, strains, dislocations and fractures.

• A sprain occurs when a ligament is stretched, torn or damaged. Ligaments connect bones to bones at the joints. Sprains most commonly affect the ankle, knee, wrist and finger joints.
• A strain occurs when a tendon or muscle is stretched, torn or damaged. Tendons connect muscles to bones. Strains often are caused by lifting something heavy or working a muscle too hard. They usually involve the muscles in the neck, back, thigh or the back of the lower leg. Some strains can reoccur, especially in the neck and back.
• A dislocation occurs when the bones that meet at a joint move out of their normal position. This type of injury is usually caused by a violent force that tears the ligaments, allowing the bones to move out of place.
• A fracture is a complete break, a chip or a crack in a bone. Fractures can be open (the end of the broken bone breaks through the skin) or closed (the broken bone does not break through the skin).

Sprains and strains both refer to damage to the soft tissues in the body, including ligaments, tendons, and muscles. They are common injuries that share some symptoms but affect different body parts. People can often treat sprains and strains at home. A sprain is an overstretched, torn, or twisted ligament. A ligament is a tough band of fibrous tissue that connects bones to other bones or cartilage. Ligaments are usually located around joints. Commonly sprained areas include the wrists, ankles, thumbs, and knees. A strain is an overstretched, torn, or twisted tendon or muscle. A tendon is a tough cord of fibrous tissue that connects muscles to bones. Commonly strained areas include the legs, knees, feet, and back.

Causes of sprains

The most common causes of sprains are falling, twisting, or experiencing trauma to the joint. These types of injuries may cause the joint to move out of its normal range of movement, tearing or stretching the ligament as this happens.

Situations that may result in a sprain include:

• walking or running on an uneven surface
• twisting or pivoting suddenly
• falling and landing on the wrist or hand
• playing racquet sports
• injuries from contact sports

Causes of strains

Strains may occur suddenly (acute) or develop slowly over time (chronic).

Causes of acute strains include:

• lifting a heavy object
• running, jumping, or throwing
• slipping or falling

Causes of chronic strains include playing sports and activities that involve repetitive movements, such as rowing, tennis or running. Sitting or standing in an awkward position for prolonged periods can also cause chronic strains.

Muscle, bone and joint injuries can be extremely painful. Sometimes the injury will be very obvious — for example, you may see the ends of a broken bone protruding through the skin, or the injured body part might appear bent or crooked (deformed). If a joint is dislocated, you may see an abnormal bump, ridge or hollow formed by the displaced end of the bone. Other times, signs and symptoms of injury may be more subtle, such as swelling or bruising.

Usually, the person will try to avoid using the injured body part because using it causes pain. In some cases, the person may be unable to move the injured body part. The person might also report feeling or hearing “popping” or “snapping” at the time of the injury, or “grating” when moving the injured part.

Sometimes when a person has a muscle, bone or joint injury, you will be able to tell right away that you need to call 103 or the designated emergency number. But not all muscle, bone or joint injuries result in obvious injuries, and some are not serious enough to summon emergency medical services (EMS) personnel. In general, call 103 or the designated emergency number if:

• A broken bone is protruding through the skin.
• The injured body part is bent, crooked or looks deformed.
• There is moderate or severe swelling and bruising.
• The person heard or felt “popping” or “snapping” at the time of the injury.
• The person hears or feels “grating” when he or she moves the injured body part.
• The person cannot move or use the injured body part.
• The injured area is cold and numb.
• The injury involves the head, neck or spine.
• The person is having difficulty breathing.
• The cause of the injury (for example, a fall from a height or getting hit by a vehicle) makes you think that the injury may be severe, or that the person may have multiple injuries.
• It is not possible to safely or comfortably move the person to a vehicle for transport to a healthcare facility.