Sprain

Last updated
Sprain
Other namesTorn ligament, distorsio
Sprained foot.jpg
A sprained ankle with bruising and swelling
Specialty Sports medicine, physical medicine & rehabilitation, orthopedics, family medicine, emergency medicine
Symptoms Pain, swelling, bruising, joint instability, limited range of motion of the injured joint
DurationMild cases - few days to six weeks Severe cases - few weeks to months
CausesTrauma, sports injuries, overuse, environmental hazards
Risk factors Environmental factors, age, poor training or sports gear
Diagnostic method Physical exam, joint x-ray
Differential diagnosis Strain, fracture
PreventionFrequent stretching and conditioning, bracing at risk joints during exercise
TreatmentRest, ice, compression, elevation, NSAIDs
Medication Non-steroidal anti-inflammatory drugs (NSAIDs)
Prognosis Mild injuries resolve well on their own. Severe injuries likely require surgery and physical therapy.

A sprain is a soft tissue injury of the ligaments within a joint, often caused by a sudden movement abruptly forcing the joint to exceed its functional range of motion. Ligaments are tough, inelastic fibers made of collagen that connect two or more bones to form a joint and are important for joint stability and proprioception, which is the body's sense of limb position and movement. [1] Sprains may be mild (first degree), moderate (second degree), or severe (third degree), with the latter two classes involving some degree of tearing of the ligament. Sprains can occur at any joint but most commonly occur in the ankle, knee, or wrist. [2] An equivalent injury to a muscle or tendon is known as a strain.

Contents

The majority of sprains are mild, causing minor swelling and bruising that can be resolved with conservative treatment, typically summarized as RICE: rest, ice, compression, elevation. However, severe sprains involve complete tears, ruptures, or avulsion fractures, often leading to joint instability, severe pain, and decreased functional ability. These sprains require surgical fixation, prolonged immobilization, and physical therapy. [3]

Signs and symptoms

Knowing the signs and symptoms of a sprain can be helpful in differentiating the injury from a strain or simple fracture. Strains typically present with pain, cramping, muscle spasm, and muscle weakness, and fractures typically present with bone tenderness, especially when bearing weight. [7]

Causes

Acute sprains typically occur when the joint is abruptly forced beyond its functional range of motion, often in the setting of trauma or sports injuries. The most common cause of sprains in general is repetitive movements (overuse). [8]

Mechanism

Ligaments are collagen fibers that connect bones together, providing passive stabilization to a joint. These fibers can be found in various organizational patterns (parallel, oblique, spiral, etc.) depending on the function of the joint involved. Ligaments can be extra-capsular (located outside the joint capsule), capsular (continuation of the joint capsule), or intra-articular (located within a joint capsule). [1] The location has important implications for healing as blood flow to intra-articular ligaments is diminished compared to extra-capsular or capsular ligaments. [9]

Collagen fibers have about a 4% elastic zone where fibers stretch out with increased load on the joint. However, exceeding this elastic limit causes a rupture of fibers, leading to a sprain. It is important to recognize that ligaments adapt to training by increasing the cross-sectional area of fibers. [10] When a ligament is immobilized, the ligament has been shown to rapidly weaken. Normal daily activity is important for maintaining about 80–90% of the mechanical properties of a ligament. [1]

Risk factors

Diagnosis

Sprains can often be diagnosed clinically based on the patient's signs and symptoms, mechanism of injury, and physical examination. However, x-rays can be obtained to help identify fractures, especially in cases of tenderness or bone pain at the injured site. [13] In some instances, particularly if the healing process is prolonged or a more serious injury is suspected, magnetic resonance imaging (MRI) is performed to look at the surrounding soft tissue and ligaments. [14]

Classification

  1. First degree sprain (mild) – There is minor stretching and structural damage to the ligament, leading to mild swelling and bruising. Patients typically present without joint instability or decreased range of motion of the joint.[ citation needed ]
  2. Second degree sprain (moderate) – There is a partial tear of the affected ligament. Patients typically experience moderate swelling, tenderness, and some instability of the joint. There may be some difficulty bearing weight on the affected joint. [15]
  3. Third degree sprain (severe) – There is a complete rupture or tear of the ligament, sometimes avulsing a piece of bone. Patients typically experience severe joint instability, pain, bruising, swelling, and inability to apply weight to the joint. [16]
Three-dimensional animation illustrating a sprain Sprain SAG.jpg
Three-dimensional animation illustrating a sprain

Joints involved

Although any joint can experience a sprain, some of the more common injuries include the following: [3]

Treatment

Treatment of sprains usually involves incorporating conservative measures to reduce the signs and symptoms of sprains, surgery to repair severe tears or ruptures, and rehabilitation to restore function to the injured joint. Although most sprains can be managed without surgery, severe injuries may require tendon grafting or ligament repair based on the individual's circumstances. [22] The amount of rehabilitation and time needed for recovery will depend on the severity of the sprain. [23]

Non-surgical

Depending on the mechanism of injury, joint involvement, and severity, most sprains can be treated using conservative measures following the acronym RICE within the first 24 hours of sustaining an injury. [24] However, it is important to recognize that treatments should be individualized depending on the patient's particular injury and symptoms. [25] Over-the-counter medications such as non-steroidal anti-inflammatory drugs (NSAIDs) can help relieve pain, and topical NSAIDs can be as effective as medications taken by mouth. [26]

Other non-operative therapies including the continuous passive motion machine (moves joint without patient exertion) and cryocuff (type of cold compress that is activated similarly to a blood pressure cuff) have been effective in reducing swelling and improving range of motion. [32] Recent studies have shown that traction is just as effective as the RICE technique in treating ankle sprains in pediatric patients. [33]

Functional rehabilitation

The components of an effective rehabilitation program for all sprain injuries include increasing the range of motion of the affected joint and progressive muscle strengthening exercises. [34] After implementing conservative measures to reduce swelling and pain, mobilizing the limb within 48–72 hours following injury has been shown to promote healing by stimulating growth factors in musculoskeletal tissues linked to cellular division and matrix remodeling. [23]

Prolonged immobilization can delay the healing of a sprain, as it usually leads to muscle atrophy and weakness. [35] Although prolonged immobilization can have a negative effect on recovery, a study in 1996 suggest that the use of bracing can improve healing by alleviating pain and stabilizing the injury to prevent further damage to the ligament or re-injury. [36] When using a brace, it is necessary to ensure adequate blood flow to the extremity. [37] Ultimately, the goal of functional rehabilitation is to return the patient to full daily activities while minimizing the risk of re-injury.

Related Research Articles

<span class="mw-page-title-main">Knee</span> Leg joint in primates

In humans and other primates, the knee joins the thigh with the leg and consists of two joints: one between the femur and tibia, and one between the femur and patella. It is the largest joint in the human body. The knee is a modified hinge joint, which permits flexion and extension as well as slight internal and external rotation. The knee is vulnerable to injury and to the development of osteoarthritis.

<span class="mw-page-title-main">Shoulder problem</span> Medical condition

Shoulder problems including pain, are one of the more common reasons for physician visits for musculoskeletal symptoms. The shoulder is the most movable joint in the body. However, it is an unstable joint because of the range of motion allowed. This instability increases the likelihood of joint injury, often leading to a degenerative process in which tissues break down and no longer function well.

<span class="mw-page-title-main">Back injury</span> Damage or wear to bones, muscles or other tissues of the back

Back injuries result from damage, wear, or trauma to the bones, muscles, or other tissues of the back. Common back injuries include sprains and strains, herniated discs, and fractured vertebrae. The lumbar spine is often the site of back pain. The area is susceptible because of its flexibility and the amount of body weight it regularly bears. It is estimated that low-back pain may affect as much as 80 to 90 percent of the general population in the United States.

<span class="mw-page-title-main">Achilles tendinitis</span> Medical condition of the ankle and heel

Achilles tendinitis, also known as achilles tendinopathy, occurs when the Achilles tendon, found at the back of the ankle, becomes sore. Achilles tendinopathy is accompanied by alterations in the tendon's structure and mechanical properties. The most common symptoms are pain and swelling around the affected tendon. The pain is typically worse at the start of exercise and decreases thereafter. Stiffness of the ankle may also be present. Onset is generally gradual.

A soft tissue injury is the damage of muscles, ligaments and tendons throughout the body. Common soft tissue injuries usually occur from a sprain, strain, a one-off blow resulting in a contusion or overuse of a particular part of the body. Soft tissue injuries can result in pain, swelling, bruising and loss of function.

<span class="mw-page-title-main">Achilles tendon rupture</span> Medical condition where the tendon at the back of the ankle breaks

Achilles tendon rupture is when the Achilles tendon, at the back of the ankle, breaks. Symptoms include the sudden onset of sharp pain in the heel. A snapping sound may be heard as the tendon breaks and walking becomes difficult.

<span class="mw-page-title-main">Tarsal tunnel syndrome</span> Medical condition

Tarsal tunnel syndrome (TTS) is a nerve entrapment syndrome causing a painful foot condition in which the tibial nerve is compressed as it travels through the tarsal tunnel. This tunnel is found along the inner leg behind the medial malleolus. The posterior tibial artery, tibial nerve, and tendons of the tibialis posterior, flexor digitorum longus, and flexor hallucis longus muscles travel in a bundle through the tarsal tunnel. Inside the tunnel, the nerve splits into three segments. One nerve (calcaneal) continues to the heel, the other two continue on to the bottom of the foot. The tarsal tunnel is delineated by bone on the inside and the flexor retinaculum on the outside.

<span class="mw-page-title-main">Strain (injury)</span> Injury due to slight tearing of a muscle or tendon

A strain is an acute or chronic soft tissue injury that occurs to a muscle, tendon, or both. The equivalent injury to a ligament is a sprain. Generally, the muscle or tendon overstretches and partially tears, under more physical stress than it can withstand, often from a sudden increase in duration, intensity, or frequency of an activity. Strains most commonly occur in the foot, leg, or back. Immediate treatment typically includes five steps abbreviated as P.R.I.C.E.: protection, rest, ice, compression, elevation.

<span class="mw-page-title-main">Ankle fracture</span> Medical condition

An ankle fracture is a break of one or more of the bones that make up the ankle joint. Symptoms may include pain, swelling, bruising, and an inability to walk on the injured leg. Complications may include an associated high ankle sprain, compartment syndrome, stiffness, malunion, and post-traumatic arthritis.

<span class="mw-page-title-main">Sprained ankle</span> Medical condition

A sprained ankle is an injury where sprain occurs on one or more ligaments of the ankle. It is the most commonly occurring injury in sports, mainly in ball sports such as basketball, volleyball, football, and tennis.

<span class="mw-page-title-main">Anterior cruciate ligament injury</span> Ligament injury near the knee

An anterior cruciate ligament injury occurs when the anterior cruciate ligament (ACL) is either stretched, partially torn, or completely torn. The most common injury is a complete tear. Symptoms include pain, an audible cracking sound during injury, instability of the knee, and joint swelling. Swelling generally appears within a couple of hours. In approximately 50% of cases, other structures of the knee such as surrounding ligaments, cartilage, or meniscus are damaged.

<span class="mw-page-title-main">Unhappy triad</span> Medical condition of the knee

The unhappy triad, also known as a blown knee among other names, is an injury to the anterior cruciate ligament, medial collateral ligament, and meniscus. Analysis during the 1990s indicated that this 'classic' O'Donoghue triad is actually an unusual clinical entity among athletes with knee injuries. Some authors mistakenly believe that in this type of injury, "combined anterior cruciate and medial collateral ligament disruptions that were incurred during athletic endeavors" always present with concomitant medial meniscus injury. However, the 1990 analysis showed that lateral meniscus tears are more common than medial meniscus tears in conjunction with sprains of the ACL.

<span class="mw-page-title-main">Jammed finger</span> Medical condition

Jammed finger is a colloquialism referring to a variety of injuries to the joints of the fingers, resulting from axial loading beyond that which the ligaments can withstand. Common parts of the finger susceptible to this type of injury are ligaments, joints, and bones. The severity of the damage to the finger increases with the magnitude of the force exerted by the external object on the fingertip. Toes may become jammed as well, with similar results.

<span class="mw-page-title-main">Meniscus tear</span> Rupturing of the fibrocartilage strips in the knee called menisci

A tear of a meniscus is a rupturing of one or more of the fibrocartilage strips in the knee called menisci. When doctors and patients refer to "torn cartilage" in the knee, they actually may be referring to an injury to a meniscus at the top of one of the tibiae. Menisci can be torn during innocuous activities such as walking or squatting. They can also be torn by traumatic force encountered in sports or other forms of physical exertion. The traumatic action is most often a twisting movement at the knee while the leg is bent. In older adults, the meniscus can be damaged following prolonged 'wear and tear'. Especially acute injuries can lead to displaced tears which can cause mechanical symptoms such as clicking, catching, or locking during motion of the joint. The joint will be in pain when in use, but when there is no load, the pain goes away.

A high ankle sprain, also known as a syndesmotic ankle sprain (SAS), is a sprain of the syndesmotic ligaments that connect the tibia and fibula in the lower leg, thereby creating a mortise and tenon joint for the ankle. High ankle sprains are described as high because they are located above the ankle. They comprise approximately 15% of all ankle sprains. Unlike the common lateral ankle sprains, when ligaments around the ankle are injured through an inward twisting, high ankle sprains are caused when the lower leg and foot externally rotates.

<span class="mw-page-title-main">Musculoskeletal injury</span> Medical condition

Musculoskeletal injury refers to damage of muscular or skeletal systems, which is usually due to a strenuous activity and includes damage to skeletal muscles, bones, tendons, joints, ligaments, and other affected soft tissues. In one study, roughly 25% of approximately 6300 adults received a musculoskeletal injury of some sort within 12 months—of which 83% were activity-related. Musculoskeletal injury spans into a large variety of medical specialties including orthopedic surgery, sports medicine, emergency medicine and rheumatology.

<span class="mw-page-title-main">Knee pain</span> Medical condition

Knee pain is pain in or around the knee.

<span class="mw-page-title-main">Medial knee injuries</span> Medical condition

Medial knee injuries are the most common type of knee injury. The medial ligament complex of the knee consists of:

Running injuries affect about half of runners annually. The frequencies of various RRI depend on the type of running, such as speed and mileage. Some injuries are acute, caused by sudden overstress, such as side stitch, strains, and sprains. Many of the common injuries that affect runners are chronic, developing over longer periods as the result of overuse. Common overuse injuries include shin splints, stress fractures, Achilles tendinitis, Iliotibial band syndrome, Patellofemoral pain, and plantar fasciitis.

<span class="mw-page-title-main">Ankle problems</span> Medical condition

Ankle problems occur frequently, having symptoms of pain or discomfort in the ankles.

References

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