Publication Date: March 1999
Questions and Answers About Sprains
This fact sheet contains general information about sprains
and strains, which are both very common injuries. Individual sections
describe what sprains and strains are, where they usually occur, what
their signs and symptoms are, how they are treated, and how they can
be prevented. At the end is a list of key words to help you understand
the terms used in the fact sheet. If you have further questions, you
may wish to discuss them with your doctor.
the Difference Between a Sprain and a Strain?
A sprain is an injury to a ligament--a stretching
or a tearing. One or more ligaments can be injured during a sprain.
The severity of the injury will depend on the extent of injury to a
single ligament (whether the tear is partial or complete) and the number
of ligaments involved.
A strain is an injury to either a muscle
or a tendon. Depending on the severity of the injury, a strain may be
a simple overstretch of the muscle or tendon, or it can result in a
partial or complete tear.
What Causes a Sprain?
A sprain can result from a fall, a sudden twist, or a
blow to the body that forces a joint out of its normal position. This
results in an overstretch or tear of the ligament supporting that joint.
Typically, sprains occur when people fall and land on an outstretched
arm, slide into base, land on the side of their foot, or twist a knee
with the foot planted firmly on the ground.
Where Do Sprains Usually
Although sprains can occur in both the upper and lower
parts of the body, the most common site is the ankle. Ankle sprains
are the most common injury in the United States and often occur during
sports or recreational activities. Approximately 1 million ankle injuries
occur each year, and 85 percent of them are sprains.
The talus bone and the ends of two of the lower leg bones
(tibia and fibula) form the ankle joint (see
fig. 1). This joint is supported by several lateral (outside) ligaments
and medial (inside) ligaments. Most ankle sprains happen when the foot
turns inward as a person runs, turns, falls, or lands on the ankle after
a jump. This type of sprain is called an inversion injury. One or more
of the lateral ligaments are injured, usually the anterior talofibular
ligament. The calcaneofibular ligament is the second most frequently
The knee is another common site for a sprain. A blow to
the knee or a fall is often the cause; sudden twisting can also result
in a sprain (see fig. 2).
Sprains frequently occur at the wrist, typically when
people fall and land on an outstretched hand.
What Are the Signs and Symptoms
of a Sprain?
The usual signs and symptoms include pain, swelling, bruising,
and loss of the ability to move and use the joint (called functional
ability). However, these signs and symptoms can vary in intensity, depending
on the severity of the sprain. Sometimes people feel a pop or tear when
the injury happens.
Doctors use many criteria to diagnose the severity of
a sprain. In general, a grade I or mild sprain causes overstretching
or slight tearing of the ligaments with no joint instability. A person
with a mild sprain usually experiences minimal pain, swelling, and little
or no loss of functional ability. Bruising is absent or slight, and
the person is usually able to put weight on the affected joint. People
with mild sprains usually do not need an x ray, but one is sometimes
performed if the diagnosis is unclear.
When To See a Doctor for a Sprain
You have severe pain and cannot put any weight
on the injured joint.
The area over the injured joint or next to it
is very tender when you touch it.
The injured area looks crooked or has lumps
and bumps (other than swelling) that you do not see on the
You cannot move the injured joint.
You cannot walk more than four steps without
Your limb buckles or gives way when you try
to use the joint.
You have numbness in any part of the injured
You see redness or red streaks spreading out
from the injury.
You injure an area that has been injured several
You have pain, swelling, or redness over a bony
part of your foot.
You are in doubt about the seriousness of the
injury or how to care for it.
A grade II or moderate sprain causes partial tearing of
the ligament and is characterized by bruising, moderate pain, and swelling.
A person with a moderate sprain usually has some difficulty putting
weight on the affected joint and experiences some loss of function.
An x ray may be needed to help the doctor determine if a fracture is
causing the pain and swelling. Magnetic resonance imaging is occasionally
used to help differentiate between a significant partial injury and
a complete tear in a ligament.
People who sustain a grade III or severe sprain completely
tear or rupture a ligament. Pain, swelling, and bruising are usually
severe, and the patient is unable to put weight on the joint. An x ray
is usually taken to rule out a broken bone.
When diagnosing any sprain, the doctor will ask the patient
to explain how the injury happened. The doctor will examine the affected
joint and check its stability and its ability to move and bear weight.
What Causes a Strain?
A strain is caused by twisting or pulling a muscle or
tendon. Strains can be acute or chronic. An acute strain is caused by
trauma or an injury such as a blow to the body; it can also be caused
by improperly lifting heavy objects or overstressing the muscles. Chronic
strains are usually the result of overuse--prolonged, repetitive movement
of the muscles and tendons.
Where Do Strains Usually
Two common sites for a strain are the back and the hamstring
muscle (located in the back of the thigh). Contact sports such as soccer,
football, hockey, boxing, and wrestling put people at risk for strains.
Gymnastics, tennis, rowing, golf, and other sports that require extensive
gripping can increase the risk of hand and forearm strains. Elbow strains
sometimes occur in people who participate in racquet sports, throwing,
and contact sports.
What Are the Signs and Symptoms
of a Strain?
Typically, people with a strain experience pain, muscle
spasm, and muscle weakness. They can also have localized swelling, cramping,
or inflammation and, with a minor or moderate strain, usually some loss
of muscle function. Patients typically have pain in the injured area
and general weakness of the muscle when they attempt to move it. Severe
strains that partially or completely tear the muscle or tendon are often
very painful and disabling.
How Are Sprains and Strains
Reduce Swelling and Pain
Treatment for sprains and strains is similar and can be
thought of as having two stages. The goal during the first stage is
to reduce swelling and pain. At this stage, doctors usually advise patients
to follow a formula of rest, ice, compression, and elevation (RICE)
for the first 24 to 48 hours after the injury (see the box below).
The doctor may also recommend an over-the-counter or prescription nonsteroidal
anti-inflammatory drug, such as aspirin or ibuprofen, to help decrease
pain and inflammation.
For people with a moderate or severe sprain, particularly
of the ankle, a hard cast may be applied. Severe sprains and strains
may require surgery to repair the torn ligaments, muscle, or tendons.
Surgery is usually performed by an orthopaedic surgeon.
It is important that moderate and severe sprains and strains
be evaluated by a doctor to allow prompt, appropriate treatment to begin.
The box above lists
some signs that should alert people to consult their doctor. However,
a person who has any concerns about the seriousness of a sprain or strain
should always contact a doctor for advice.
Reduce regular exercise or activities of daily living as needed.
Your doctor may advise you to put no weight on an injured area
for 48 hours. If you cannot put weight on an ankle or knee, crutches
may help. If you use a cane or one crutch for an ankle injury,
use it on the uninjured side to help you lean away and relieve
weight on the injured ankle.
Apply an ice pack to the injured area for 20 minutes at a time,
4 to 8 times a day. A cold pack, ice bag, or plastic bag filled
with crushed ice and wrapped in a towel can be used. To avoid
cold injury and frostbite, do not apply the ice for more than
Compression of an injured ankle, knee, or wrist may help reduce
swelling. Examples of compression bandages are elastic wraps,
special boots, air casts, and splints. Ask your doctor for advice
on which one to use.
If possible, keep the injured ankle, knee, elbow, or wrist elevated
on a pillow, above the level of the heart, to help decrease swelling.
The second stage of treating a sprain or strain is rehabilitation,
whose overall goal is to improve the condition of the injured part and
restore its function. The health care provider will prescribe an exercise
program designed to prevent stiffness, improve range of motion, and
restore the joint's normal flexibility and strength. Some patients may
need physical therapy during this stage.
When the acute pain and swelling have diminished, the
health care provider or physical therapist will instruct the patient
to do a series of exercises several times a day. These are very important
because they help reduce swelling, prevent stiffness, and restore normal,
pain-free range of motion. The health care provider can recommend many
different types of exercises, depending on the injury. For example,
people with an ankle sprain may be told to rest their heel on the floor
and write the alphabet in the air with their big toe. A patient with
an injured knee or foot will work on weight-bearing and balancing exercises.
The duration of the program depends on the extent of the injury, but
the regimen commonly lasts for several weeks.
Another goal of rehabilitation is to increase strength
and regain flexibility. Depending on the patient's rate of recovery,
this process begins about the second week after the injury. The health
care provider or physical therapist will instruct the patient to do
a series of exercises designed to meet these goals. During this phase
of rehabilitation, patients progress to more demanding exercises as
pain decreases and function improves.
The final goal is the return to full daily activities,
including sports when appropriate. Patients must work closely with their
health care provider or physical therapist to determine their readiness
to return to full activity. Sometimes people are tempted to resume full
activity or play sports despite pain or muscle soreness. Returning to
full activity before regaining normal range of motion, flexibility,
and strength increases the chance of reinjury and may lead to a chronic
The amount of rehabilitation and the time needed for full
recovery after a sprain or strain depend on the severity of the injury
and individual rates of healing. For example, a moderate ankle sprain
may require 3 to 6 weeks of rehabilitation before a person can return
to full activity. With a severe sprain, it can take 8 to 12 months before
the ligament is fully healed. Extra care should be taken to avoid reinjury.
Can Sprains and Strains Be
There are many things people can do to help lower their
risk of sprains and strains:
- Maintain a healthy, well-balanced diet to keep muscles strong.
- Maintain a healthy weight.
- Practice safety measures to help prevent falls (for example, keep
stairways, walkways, yards, and driveways free of clutter, and salt
or sand icy patches in the winter).
- Wear shoes that fit properly.
- Replace athletic shoes as soon as the tread wears out or the heel
wears down on one side.
- Do stretching exercises daily.
- Be in proper physical condition to play a sport.
- Warm up and stretch before participating in any sports or exercise.
- Wear protective equipment when playing.
- Avoid exercising or playing sports when tired or in pain.
- Run on even surfaces.
Where Can People Find More
Information About Sprains and Strains?
- National Institute of Arthritis and Musculoskeletal and Skin
Diseases Information Clearinghouse
NIAMS/National Institutes of Health
1 AMS Circle
Bethesda, MD 20892-3675
The clearinghouse provides information on arthritis and
musculoskeletal and skin diseases. Additional information and updates
can also be found on the NIAMS Web site.
- American Academy of Orthopaedic Surgeons
P.O. Box 2058
Des Plaines, IL 60017
Phone: 800-824-BONE (2663) (free of charge)
The academy provides education and practice management services for orthopaedic surgeons and allied health professionals. It also serves as an advocate for improved patient care and informs the public about the science of orthopaedics. The orthopaedist's scope of practice includes disorders of the body's bones, joints, ligaments, muscles, and tendons. For a single copy of an AAOS brochure, send a self-addressed stamped envelope to the address above or visit the AAOS Web site.
The NIAMS gratefully acknowledges the assistance of James
S. Panagis, M.D., M.P.H., of NIAMS; Jo A. Hannafin, M.D., Ph.D., of
the Hospital for Special Surgery, New York, NY; and Harold B. Kitaoka,
M.D., of the Mayo Clinic, Rochester, MN, in the preparation and review
of this fact sheet.
The National Institute of Arthritis and Musculoskeletal
and Skin Diseases (NIAMS), a part of the National Institutes of
Health (NIH), leads the Federal medical research effort in arthritis
and musculoskeletal and skin diseases. The NIAMS supports research
and research training throughout the United States, as well as
on the NIH campus in Bethesda, Maryland, and disseminates health
and research information. The NIAMS Information Clearinghouse
is a public service that provides health information and information
Sprains and Strains Key Words
- Acute: An illness or injury that lasts for a short time and
may be intense.
- Chronic: An illness or injury that lasts for a long time.
- Femur: The upper leg or thigh bone, which extends into the
hip socket at its upper end and down to the knee at its lower end.
- Fibula: The thin, outer bone of the leg that forms part
of the ankle joint at its lower end.
- Inflammation: A characteristic reaction of tissues to disease
or injury; it is marked by four signs: swelling, redness, heat, and
- Joint: A junction where two bones meet.
- Ligament: A band of tough, fibrous tissue that connects
two or more bones at a joint and prevents excessive movement of the
- Muscle: Tissue composed of bundles of specialized cells
that contract and produce movement when stimulated by nerve impulses.
- Range of motion: The arc of movement of a joint from one
extreme position to the other; range-of-motion exercises help increase
or maintain flexibility and movement in muscles, tendons, ligaments,
- Tendons: Tough, fibrous cords of tissue that connect muscle
- Tibia: The thick, long bone of the lower leg (also called
the shin) that forms part of the knee joint at its upper end and the
ankle joint at its lower end.