Sports injuries are common among athletes and other people who participate in sports. Certain injuries that are traditionally considered sports injuries can also occur in people who do not participate in sports. For example, homemakers and factory workers often develop “tennis elbow,” although they may never have played tennis.
Sports participation always carries the risk of injury. Sports injuries are more likely when people do not warm up properly (exercising and stretching muscles at a relaxed pace before an intense workout—see Warming up).
Muscles and ligaments are injured when subjected to forces greater than their inherent strength. For example, they may be injured if they are too weak or tight for the exercise being attempted. Joints are more prone to injury when the muscles and ligaments that support them are weak, as they are after a sprain.
Individual differences in body structure can make people susceptible to sports injuries by stressing parts of the body unevenly. For example, when legs are unequal in length, forces on the hips and knees are unequal and place more stress on one side of the body.
Excessive pronation—rolling onto the inside of the foot after it strikes the ground—can cause foot and knee pain. Some degree of pronation is normal and prevents injuries by helping distribute the foot's striking force throughout the foot. In people with excessive pronation, the feet are so flexible that the long arch flattens out, allowing the inner part of the foot to come close to touching the ground during walking or running and giving the appearance of flatfeet. Runners with excessive pronation may develop knee pain when running long distances because the knee caps tend to turn outward when the feet turn inward. This position in turn places excessive pressure across the front of the knee.
The opposite problem—too little pronation—can occur in people who have rigid ankles. In these people, the feet appear to have very high arches and do not absorb shock well, increasing the risk of developing small cracks in the bones (stress fractures—see Stress Fractures of the Foot) of the feet and legs.
The way in which the legs are aligned can produce pain, particularly in women with wide hips. Such women develop a tendency for the knee caps to be pushed outward from the midline. This force on the knee caps causes pain.
Generally, sports injuries can be divided into four categories:
One of the most common causes of sports injuries is overuse (excessive wear and tear). Overuse injuries are often due to faulty technique. An example of an improper technique is running along the same side of a banked road. Repeatedly hitting the slightly higher surface with the same foot results in different forces being applied to the right and left hips and knees. This difference in forces increases the risk of injury on the side striking the higher surface and changes the forces acting on the other leg, risking injury to it as well.
Some athletes increase the speed or intensity of their workouts too quickly, putting stress on the muscles. For example, some runners who increase speed or distance too quickly during training stress the legs, hips, or feet. This extra stress often leads to muscle sprains and stress fractures of the bones.
Some athletes overly train one set of muscles without equally strengthening the opposite group of muscles, resulting in imbalances that can contribute to injury.
Another factor contributing to overuse injuries is inadequate recovery after a workout. Also, some people do not stop exercising when pain develops (working through the pain). Continuing to exercise when pain is present injures more muscle or connective tissue, extending the damage and delaying recovery, whereas rest allows recovery.
Blunt athletic trauma can result in bruises, concussions, and fractures. This type of injury usually involves high-impact collisions with other athletes or objects (for example, being tackled in football or checked into the sideboards in hockey), falls, and direct blows (for example, in boxing and the martial arts).
Fractures and dislocations:
Fractured bones and dislocations of a joint are serious injuries that require immediate medical attention (see Overview of Fractures, Dislocations, and Sprains). People with these injuries often have deformity of a limb, intense pain, and dysfunction of the limb or joint and must be further evaluated with diagnostic tests, such as x-rays. When people suspect that they have a fracture or dislocated joint, they should splint the limb “as it lies” without moving it and go to the emergency department.
Stress fractures are small cracks in bone caused by repetitive stress injury. They are most common in the feet or long bones of the legs. They may cause no visible signs of injury and do not always appear on x-rays. The only symptom is pain when the person tries to put weight on the injured foot (see Stress Fractures of the Foot).
Sprains and strains:
Sprains and strains (see Overview of Fractures, Dislocations, and Sprains) typically occur with sudden, forceful exertion, most commonly during running, particularly with sudden changes of direction (for example, while dodging and avoiding competitors in football). Such injuries also are common in strength training, when people quickly drop or yank the load rather than moving slowly and smoothly with constant controlled tension.
Injury always causes pain, which can range from mild to severe. Injured tissue may have any combination of the following characteristics:
To diagnose a sports injury, doctors ask when and how the injury happened, what recreational and occupational activities the person has recently or routinely been engaged in, and whether there has been a change in the intensity of the activity. They may ask whether the person has taken certain antibiotics that increase the risk of tendon injury (for example, ciprofloxacin or levofloxacin). Doctors also examine the injured area.
People may be referred to a specialist for further testing. Diagnostic tests may include x-rays, computed tomography (CT), magnetic resonance imaging (MRI), ultrasonography, bone scanning, dual-energy x-ray absorptiometry (DEXA scanning—see Dual-Energy X-Ray Absorptiometry (DXA)), and electromyography (EMG—see Electromyography and Nerve Conduction Studies).
General measures that help increase safety during exercise, including proper warm up, cool down, and hydration, are discussed elsewhere (see Exercising Safely). Exercise itself helps prevent injuries because tissues become more resilient to the stresses of vigorous activities.
Use of proper equipment can help prevent injuries. For example, wearing helmets and mouth guards can help prevent injuries while playing football. For running athletes, good running shoes are essential. Running shoes should have a rigid heel counter (the back part of the shoe that surrounds the heel) to control movement of the back of the foot, a support across the instep (saddle) to prevent excessive pronation, and a padded opening (collar) to support the ankle.
Shoe inserts (orthotics) can sometimes help correct problems such as excessive pronation. The inserts, which may be flexible, semirigid, or rigid and may vary in length, should be fitted into appropriate running shoes. The shoes must have adequate space for the inserts, which replace the inserts found in the shoes at the time of purchase.
Stopping exercise at the first sign of pain, which precedes most overuse injuries, limits the degree of injury to muscles and tendons.
After sustaining a sports injury, athletes often want to know how quickly they can resume activity. Recovery time depends on the severity of the injury. Initially, exercise of previously injured areas should be of low intensity to strengthen weak muscles, tendons, and ligaments and prevent re-injury. Often, athletes need to adjust their technique to avoid re-injury. For example, a racquet sports player who has tennis elbow may need to alter technique for use of the racquet.
Treatment of sports injuries is similar to treatment of non-sports injuries.
Immediate treatment for almost all injuries consists of PRICE:
Protection involves immediately resting and splinting the injured part to minimize internal bleeding and swelling and to prevent further injury (Fig. 2: Commonly Used Techniques for Immobilizing a Joint).
The injured part swells because fluid leaks from blood vessels. By causing the blood vessels to constrict, ice reduces their tendency to leak, thus limiting swelling. Ice also helps to reduce pain and muscle spasms and limit tissue damage.
Ice and cold packs should not be applied directly to the skin, because doing so could irritate or damage the skin. They should be enclosed (for example, in plastic) and placed over a towel or facecloth. An elastic bandage can be wrapped around the ice pack to keep it in place while the injured part is elevated. The ice is removed after 20 minutes, left off for 20 minutes or longer, and then reapplied for 20 minutes. This process can be repeated several times during the first 24 hours.
Whether or not ice is in place, wrapping the injured part with an elastic bandage compresses the injured tissue and limits internal bleeding and swelling. The wrap is thus kept on until the injury heals.
The injured area should be elevated above heart level so that gravity can help drain the accumulated fluid that causes swelling and pain. If possible, fluid should drain on an entirely downhill path from the injured area to the heart. For example, for a hand injury, the elbow, as well as the hand, should be elevated.
Analgesics can be used to lessen pain. Acetaminophen is usually effective for pain but does not reduce inflammation. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, can be used for pain and inflammation but have a slightly higher risk of side effects (most often stomach upset) than acetaminophen. If pain is severe or persists for more than 3 days, a medical evaluation is recommended.
Injections of corticosteroids into an injured joint or the surrounding tissues are sometimes used in addition to PRICE to relieve pain and reduce swelling. However, corticosteroid injections can delay healing, increase the risk of tendon and cartilage damage, and enable a person to use an injured joint before it is fully healed, perhaps worsening the injury, and should only be done by a doctor.
After the initial injury has healed, the person should rehabilitate the injured area before resuming the activity that led to the injury. Rehabilitation may involve formal regimens carried out under the supervision of a physical therapist or athletic trainer or less formal strengthening and conditioning done without supervision. Sometimes a physical therapist provides instructions for exercises that athletes can do on their own. Physical therapists may incorporate heat, cold, electricity, sound waves, traction, or water exercise into a treatment plan in addition to therapeutic exercises (see Setting). How long physical therapy is needed depends on the severity and complexity of the injury.
The activity or sport that caused the injury should be avoided or modified until the injury has healed. Complete inactivity causes muscles to lose mass, strength, and endurance. Therefore, substituting activities that do not stress the injured part is preferable to abstaining from all physical activity. Substitute activities include bicycling, swimming, and rowing when the leg or foot is injured. Swimming and bicycling are good substitutes when the lower back is injured.
Last full review/revision January 2015 by Paul L. Liebert, MD