Overview of Sprains and Other Soft-Tissue Injuries
Most injuries to muscles and the tissues that connect them result from injuries or overuse.
The injured part hurts (especially when it is used), is usually swollen, and may be bruised.
Other injuries, such as fractures, dislocations, blood vessel and nerve damage, compartment syndrome, infections, and long-lasting joint problems, may also be present or develop.
Doctors can sometimes diagnose these problems based on symptoms, the circumstances causing the injury, and results of a physical examination, but sometimes x-rays or other imaging tests are needed.
Most injuries heal well and result in few problems, but how long they take to heal varies, depending on many factors, such as the person's age, the type and severity of the injury, and other disorders present.
Treatment depends on the type and severity of the injury and may include pain relievers, PRICE (protection, rest, ice, compression, and elevation), immobilization of the injured part (for example, with a cast or splint), and sometimes surgery.
Bones, muscles, and the tissues that connect them (ligaments, tendons, and other connective tissue, which are called soft tissues) make up the musculoskeletal system. These structures give the body its form, make it stable, and enable it to move.
Tissues of the musculoskeletal system can be damaged in various ways:
Sprains: Ligaments (which attach bone to bone) can be torn.
Strains: Muscles can be torn.
Tendon rupture: Tendons (which attach muscle to bone) can be torn.
Fractures: Bones can be cracked or broken. Usually, the surrounding tissues are also injured.
Dislocations: The bones in a joint may become completely separated from each other (called dislocation) or only partly out of position (called subluxation).
Sprains, strains, and other musculoskeletal injuries vary greatly in severity and in the treatment needed.
Sprains and strains can be
Tendons may also be completely or partially torn. If a tendon is completely torn, the affected body part usually cannot move. If only part of the tendon is torn, movement is unaffected, but the tendon may continue to tear and may later tear completely, particularly if people put substantial pressure on the affected part.
Many partial tears in ligaments, tendons, or muscles heal spontaneously.
Complete tears often require surgery.
Muscles and other soft tissues may be seriously damaged when a bone is fractured or dislocated. The skin, nerves, blood vessels, and organs may also be damaged. These injuries can cause temporary or permanent problems.
Trauma is the most common cause of soft-tissue and other musculoskeletal injuries.
How severe an injury is depends partly on how strong the force is.
Sprains and strains are common sports injuries. For example, they can occur during running, especially when people suddenly change direction, or during strength training—for example, when weight lifters quickly drop or yank the load rather than moving slowly and smoothly.
The most obvious symptom of soft-tissue injuries is
The injured part hurts, especially when people try to put weight on it or use it. The area around the injury is tender to the touch. Other symptoms include
Bruising or discoloration
Muscle spasms (unintended contraction of muscles)
Inability to use the injured part normally
Possibly loss of feeling (numbness or abnormal sensations)
A part that looks distorted, bent, or out of place (which suggests that a fracture or a dislocation has also occurred)
The injured part (such as an arm, a leg, a hand, a finger, or a toe) often cannot be moved normally because movement is painful and/or a structure (muscle, tendon, or ligament) is damaged.
Swelling may take several hours to develop. If no swelling occurs within this time, a severe sprain is unlikely.
Bruises appear when bleeding occurs under the skin. The blood comes from broken blood vessels in the injured tissues. At first, the bruise is purplish black, then slowly turns green and yellow as the blood is broken down and reabsorbed back into the body. The blood can move quite a distance from the injury, causing a large bruise or a bruise some distance from the injury. For example, a bruise on the forehead can cause a bruise to later appear under the eyes. It can take a few weeks for blood to be reabsorbed. The blood can cause temporary pain and stiffness in the surrounding structures.
Because moving the injured part is so painful, some people are unwilling or unable to move it. If people (such as young children or older people) cannot speak, refusal to move a body part may be the only sign of an injury. However, some injuries do not keep people from moving the injured part. Being able to move an injured part does not mean that there is no injury.
Soft-tissue injuries can be accompanied by or lead to other problems (complications). For example, the injured limb may no longer be able to function normally. However, serious complications are uncommon. The risk of serious complications is increased if the skin is torn or if blood vessels or nerves are damaged.
Some complications (such as blood vessel and nerve damage) occur during the first hours or days after the injury. Others (such as problems with healing and with joints) develop over time.
Rarely, what appears to be a severe sprain (for example, of the knee) may be a dislocation that has slipped back in place on its own. These dislocations may damage an artery and disrupt the blood supply to the injured limb. A disrupted blood supply may not cause any symptoms until several hours after the injury. Untreated, such damage can lead to loss of the limb.
Sometimes nerves are stretched, bruised, crushed, or torn. A direct blow can bruise or crush a nerve. Crushing causes more damage than bruising. Nerve damage causes numbness and sometimes tingling in the area past where the nerve is damaged. These injuries usually heal on their own over weeks to months to years, depending on the severity of the injury. Torn nerves do not heal spontaneously and may have to be repaired surgically. Some nerve injuries never heal completely.
Joints can become stiff if they must be kept from moving (immobilized) for a long time—for example, by a splint or cast. The knee, elbow, and shoulder are particularly likely to become stiff after an injury, especially in older people.
Physical therapy is usually needed to prevent stiffness and help the joint move as normally as possible.
Severe sprains can make a joint unstable. Having unstable joints can be disabling and increases the risk of osteoarthritis. Appropriate treatment can help prevent permanent problems.
Rarely, swelling under a cast is severe enough to contribute to compartment syndrome. Because the swelling puts pressure on nearby blood vessels, blood flow to the injured limb is reduced or blocked. As a result, tissues in the limb may be damaged or die, and the limb may have to be amputated.
To diagnose sprains, strains, and tendon injuries, doctors ask detailed questions about the injury and do a thorough physical examination. They can often diagnose soft-tissue injuries based on this information and the results of the physical examination.
If a musculoskeletal problem occurs suddenly, people must decide whether to go to an emergency department, call their doctor, or wait and see whether the problem (pain, swelling, or other symptoms) goes away and lessens on its own.
People should be taken to an emergency department, often by ambulance, if any of the following apply:
The problem is obviously serious (for example, if it resulted from a car crash or if people cannot use the injured body part).
They suspect that they have a fracture (a possible exception is a toe or fingertip injury).
They suspect they have a severe dislocation or soft-tissue injury (such as a torn tendon or severe sprain or strain).
They have several injuries.
They have symptoms of a complication—for example, if they lose sensation in the affected body part, they cannot move the affected part normally, the skin feels cool or turns blue, or the injured part is weak.
They cannot put any weight on the affected body part.
An injured joint feels unstable.
People should call a doctor when
If none of the above apply and the injury seems minor, people can call the doctor or wait and see whether the problem goes away on its own.
If injuries result from a serious accident, the doctor's first priority is
To check for severe injuries and complications, such as an open wound, nerve damage, significant blood loss, disrupted blood flow, and compartment syndrome, which can develop when the blood supply to an injured limb is reduced or blocked
For example, doctors check for numbness, measure blood pressure (which is low in people who have lost a lot of blood), check pulses (which are absent or weak when blood flow is disrupted), and look for other signs of disrupted blood flow, such as skin that is pale and cool. If any of these injuries and complications are present, doctors treat them as needed, then continue with the evaluation.
People should be checked for fractures and dislocations as well as ligament, tendon, and muscle injuries. Sometimes doctors must first make sure that there are no fractures before they do parts of this evaluation.
Doctors ask the person (or a witness) to describe what happened. The person may not remember how an injury occurred or cannot describe it accurately. Knowing how the injury occurred can help doctors determine the type of injury. For example, if a person reports that a snap or pop occurred, the cause may be an injury to a ligament or tendon. Also, doctors ask in which direction the joint was stressed during the injury. This information can help doctors determine which ligaments and/or bones may be damaged.
Doctors also ask when the pain started. If it started immediately after the injury, the cause may be a severe sprain. If the pain began hours to days later, the injury is usually minor. If the pain is more severe than expected for the injury or if the pain steadily worsens during the first hours after the injury, compartment syndrome may have developed or blood flow may be disrupted.
The person is also asked about past injuries and use of drugs that can increase the risk of tendon tears (including corticosteroids and fluoroquinolone antibiotics such as ciprofloxacin).
The physical examination includes the following (in order of priority):
To check for signs of blood vessel damage and disrupted blood flow, doctors check pulses and skin color and temperature. When blood flow is disrupted (as can occur in compartment syndrome), pulses may be absent or weak and the skin may be pale and cool. Doctors measure blood pressure, which is usually low in people who have lost a lot of blood.
To check for nerve damage, doctors evaluate sensation in the skin—whether the person can feel normally—and ask whether the person has abnormal sensations, such as a pins-and-needles sensation, tingling, or numbness. Abnormal sensations suggest that nerves have been damaged.
Doctors gently feel the injured part to determine whether the area is tender and whether tendons or muscles feel abnormal. If a fracture or dislocation is present, doctors may feel that bones are in pieces or out of place. Doctors also check for swelling and bruising. They ask whether the person can use, put weight on, and move the injured part.
Doctors test the stability of a joint by gently moving it in a way that puts stress on the joint (called stress testing). If the joint feels very unstable, doctors suspect a severe ligament injury (or a dislocation). However, if a fracture is possible, x-rays are done first to determine whether moving the joint is safe.
Moving the affected joint can also help doctors determine the severity of an injury. For example, they can determine how severe a sprain (a torn ligament) is based on how far they can move the joint and how painful the movement is. When a ligament is partially torn, moving the joint is very painful. When a ligament is completely torn, moving the joint is less painful because the torn ligament is not being stretched as the joint is moved. A joint can usually be moved more freely when a ligament is torn than when it is not and can be moved more freely when a ligament is completely torn than when it is partially torn.
Because tendons connect muscles to bone, doctors can often determine the severity of a tendon injury by moving the muscle that the tendon is attached to. When a tendon is completely torn, moving the muscle attached to the tendon may not move the bone. For example, if the Achilles tendon (which attaches the calf muscles to the heel bone) is completely torn, the foot may not move. Partial tears may be hard to detect because the joint may seem to move normally.
Doctors also check the joint above and below the injured joint.
If pain or muscle spasms interfere with the examination, doctors may give the person a pain reliever and/or muscle relaxant by mouth or injection, or a local anesthetic may be injected into the injured area to make the examination easier. Or the injured part may be immobilized until the spasms stop, usually for a few days, and then examined.
Imaging tests are done to check for possible fractures and dislocations and to identify soft-tissue injuries. These tests include
X-rays are not always needed. They do not show injuries to ligaments, tendons, or muscles. They show only bones (and the fluid that collects around an injured joint). However, x-rays may be done to check for fractures and dislocations, which may also be present. In addition, x-rays can show abnormalities in the position of bones that may suggest a sprain or other soft-tissue injury.
X-rays, if needed, are usually taken from at least two angles. If a fracture is present, two x-rays can show how the fragments of bone are aligned.
MRI can show soft tissues, which are not usually visible on x-rays. MRI thus helps detect injury to tendons, ligaments, cartilage, and muscle.
CT or MRI may be done to check for subtle fractures, which may accompany a soft-tissue injury.
Other tests may be done to check for injuries that can accompany a soft-tissue injury:
If people think that they have a severe injury, they should go to an emergency department. If they cannot walk or have several injuries, they should go by ambulance. Until they can get medical help, they should do the following:
In the emergency department, doctors check for any injuries that require immediate treatment or may cause serious complications, such as compartment syndrome. Without treatment, complications may get worse, becoming more painful and making loss of function more likely.
To make sure the injured part is not deprived of blood, doctors surgically repair damaged arteries unless the arteries are small and blood flow is not affected.
Severed nerves are also repaired surgically, but this surgery can be delayed until several days after the injury if necessary. If nerves are bruised or damaged, they may heal on their own.
If the skin is torn, the wound is covered with a sterile dressing, and the injured person is given a vaccine to prevent tetanus and antibiotics to help prevent infection. Also, the wound is cleaned, usually after a local anesthetic is used to numb the area.
PRICE refers to the combination of protection, rest, ice, compression (pressure), and elevation. This treatment is used to treat injured muscles, ligaments, and tendons.
Protection helps prevent further injury that could worsen the original one.Typically, a splint or other device is applied.
Rest prevents further injury and may speed healing. People should limit their activity and avoid putting weight on and/or using the injured body part. For example, they should not participate in contact sports, and they should use crutches if needed.
Ice and compression minimize swelling and pain. Ice is enclosed in a plastic bag, towel, or cloth and applied for 15 to 20 minutes at a time, as often as possible during the first 24 to 48 hours. Usually, compression is applied to the injury with an elastic bandage.
Elevating the injured limb helps drain fluid away from the injury and thus reduce swelling. The injured limb is elevated above heart level for the first 2 days.
After 48 hours, people can periodically apply heat (for example, with a heating pad) for 15 to 20 minutes at a time. Heat may relieve pain. However, whether heat or ice is best is unclear, and what works best may vary from one person to another.
Keeping a limb from moving (immobilization) reduces pain and helps with healing by preventing further injury to surrounding tissues. Joints on both sides of the injury are immobilized.
If immobilization lasts too long (for example, for more than a few weeks in young adults), the joint may become stiff, sometimes permanently, and muscles may shorten (causing contractures) or shrink (waste away, or atrophy). Blood clots may develop. Such problems can develop quickly, and contractures can become permanent, usually in older people. Consequently, doctors encourage movement as soon as the injury heals. They also tend to use treatments that enable older people to walk as soon as possible, rather than ones that require them to be immobilized for a long time (such as bed rest or a cast).
Whether immobilization is required and which technique is used depend on the type of injury.
If a partial tear in a tendon is suspected or if the diagnosis is uncertain, doctors may apply a splint to immobilize the injured part so that the tendon can heal. Some severe tendon tears are immobilized for days or weeks, sometimes with a cast.
Mild sprains are immobilized briefly if at all. Moving the injured part as soon as possible is usually the best treatment. Moderate sprains are often immobilized with a sling or splint for a few days. Some severe sprains and tendon tears are immobilized for days or weeks, sometimes with a cast. However, some severe sprains must be surgically repaired and are not always immobilized.
Casts are usually used for injuries that must be kept immobilized for weeks.
To apply a cast, doctors wrap the injured part in cloth, then apply a layer of soft cottony material to protect the skin from pressure and rubbing. Over this padding, doctors wrap dampened plaster-filled cotton bandages or fiberglass strips, which harden when they dry. Plaster is often used to immobilize broken bones that have been separated because it molds well and is less likely to rub against the body. Fiberglass casts are stronger, lighter, and longer-lasting. After a week or so, the swelling goes down. Then, the plaster cast can sometimes be replaced with a fiberglass cast to fit the limb more snugly.
People who require a cast are given special instructions for its care. If a cast is not correctly cared for, problems can develop. For example, if the cast becomes wet, the protective padding under the cast may become wet, and drying it completely may be impossible. As a result, the skin can soften and break down, and sores may form. Also, if a plaster cast gets wet, it can fall apart and thus no longer protect and immobilize the injured area. People are instructed to keep the cast elevated as much as possible at or above heart level, especially for the first 24 to 48 hours. They should also regularly flex and extend their fingers or wiggle their toes. These strategies help blood drain from the injured limb and thus prevent swelling.
Rarely, casts cause pain, pressure, or numbness that remains constant or worsens over time. Such symptoms must be reported to a doctor immediately. These symptoms may be due to a developing pressure sore or compartment syndrome. In such cases, doctors may have to remove the cast and apply another one.
A splint can be used to immobilize some sprains and other injuries, particularly if they need to be kept immobile for only a few days or less. Splints allow people to apply ice and to move more than a cast does.
A splint is a long, narrow slab of plaster, fiberglass, or aluminum applied with elastic wrap or tape. Because the slab does not completely encircle the limb, there is room for some expansion due to swelling. Thus, a splint does not increase the risk of developing compartment syndrome. Some injuries that eventually require a cast are first immobilized with a splint until most of the swelling resolves.
A sling by itself can provide some support. Slings can be useful when complete immobilization has undesirable effects. For example, if a shoulder is completely immobilized, the tissues around the joint may become stiff, sometimes within days, preventing the shoulder from moving (called frozen shoulder). Slings limit movement of the shoulder and elbow but allow movement of the hand.
A swathe, which is a piece of cloth or a strap, may be used with a sling to prevent the arm from swinging outward, especially at night. The swathe is wrapped around the person's back and over the injured part.
Many 3rd-degree sprains and tendon tears require surgical repair.
Most soft-tissue injuries heal well and result in few problems. However, some do not completely heal even though they are diagnosed and treated appropriately.
How long an injury takes to heal varies from weeks to months depending on
For example, children heal much faster than adults, and certain disorders (including those that cause problems with circulation, such as diabetes and peripheral vascular disease), slow healing. Partial tears in ligaments, tendons, and muscles tend to heal spontaneously, but complete tears often require surgery.
Being immobilized makes joints stiff, and muscles weaken and shrink because they are not used. If a limb is immobilized in a cast, the affected joint becomes stiffer each week, and eventually people become unable to fully extend and flex their limb. Such problems can develop quickly and become permanent, usually in older people. After wearing a long leg cast (upper thigh to the toes) for a few weeks, the muscles usually shrink so much that people can insert their hand into the formerly tight space between the cast and their thigh. When the cast is removed, their muscles are very weak and look noticeably smaller.
To prevent or minimize stiffness and to help people maintain muscle strength, doctors or physical therapists recommend daily exercise, including range-of-motion exercises and muscle-strengthening exercises. While the injury is healing, people can exercise the rest of their body, as instructed by their doctor or physical therapist.
After the injury has healed sufficiently and the joint is no longer immobilized, people can start exercising the injured limb. When exercising, they should pay attention to how the injured limb feels and avoid exercising too forcefully. If the muscles are too weak for people to exercise them, a therapist moves their limbs for them (called passive exercise). However, ultimately, to regain full strength of an injured limb, people must move their own muscles (called active exercise).
Exercises to improve range of motion and muscle strength and to strengthen and stabilize the injured joint can help prevent injuries from recurring and help prevent long-term impairment.
Most people feel some discomfort during activities, even after injuries have healed enough to allow them to put their full weight on the injured part.