What is Leg Pain?
Leg pain explained by Denver, Golden, Aurora, Boulder, Broomfield, Jefferson, and Littleton Colorado’s top pain doctors
Leg pain is a common complaint that usually develops after an injury. Injuries that typically lead to leg pain that persists for several days or even weeks can include injuries incurred during participation in sporting events, recreational activities, and exercise. The gradual wear and tear on joints or other structures that make up the leg can also lead to leg pain. In most cases, leg pain is not serious although persistent pain may indicate that an underlying condition is present.
Symptoms associated with leg pain vary widely according to the event or condition that caused the pain. However, three categories of leg pain have been characterized: leg pain that has a musculoskeletal origin; leg pain that has a nervous system origin; and leg pain that has a circulatory system origin. Although leg pain may originate in several different regions, the level of discomfort that is typically experienced arises in the bones, ligaments, muscles, and tendons in the leg. Furthermore, when leg pain is the result of a nervous system related issue, it often begins in the lower back and the buttocks and then extends down into the legs due to inflammation of the sciatic nerve. When leg pain is the result of a circulatory system or musculoskeletal-related condition, the symptoms that develop are similar in nature. However, if individuals are experiencing leg pain due to a circulatory health problem they typically only present bodily symptoms on one side.
It is important that a treatment regimen be established only after the condition causing the leg pain or the exact event that led to it has been thoroughly investigated and identified. Accordingly, several different types of treatments may be recommended. Individuals who are concerned about intense leg pain should speak with a physician before the pain becomes chronic. The physical examination usually entails gathering information regarding the patient’s medical history as well as a detailed account of an event that may have led to the pain. When it is hard to determine the exact cause, a physician will run several tests in order to rule out possible conditions before suggesting a treatment.
Causes Of Leg Pain
Leg pain may arise for numerous reasons, but damage to joints, muscles, and ligaments are generally the underlying reason for acute or chronic pain. In addition, degenerative or pathological diseases can lead to leg pain. Furthermore, some individuals have reported experiencing sharp, stabbing pain that is felt in a specific area, while others have reported feeling pain that is more widespread and radiates to regions in the body. Leg pain that has become chronic, which is described as pain that has persisted for at least three months, often fluctuates in terms of severity. For instance, sometimes leg pain decreases during warm weather and worsens during cold weather.
The pattern of an individual’s symptoms is dependent upon the underlying source, but commonly reported complaints include stiffness, cramping, muscle spasms, numbness, tingling, radiating pain, sensitivity to pressure or touch, and muscle weakness. However, more serious symptoms such as internal bleeding or blood clots actually necessitate immediate medical attention.
Overall, persistent pain in the body or leg region is generally a good indication that tissue damage has occurred or an even more serious injury. Once a diagnosis have been made, numerous treatment options may be suggested that aim at helping a patient experience relief from incapacitating pain, while augmenting healing within the body.
When an individual begins to experience serious leg pain and seeks professional pain management from a specialized physician, health-related issues with the musculoskeletal, nervous, or circulatory system are usually thoroughly examined. There are cases where a physician may be unable to properly diagnose the condition that is causing the pain, but this is not a common occurrence. The following sections describe conditions that may arise from one of the aforementioned systems in the body that typically result in persistent leg pain.
Musculoskeletal System-Related Causes Of Leg Pain
Muscle cramps in the legs, which may also be described by some patients as muscle spasms, are a very common complaint. A “Charley horse” is another name that is frequently used to describe muscle cramps. This type of cramp occurs when leg muscles begin to involuntarily contract. In most cases, this indicates that an individual is dehydrated. When dehydration develops, the levels of sodium, magnesium, potassium, and calcium in the blood stream become dangerously low and it is believed that this leads to painful muscle cramps in the legs.
Certain medications have also been known to cause muscle cramps. For example, individuals who take hydrochlorothiazide or furosemide, which are diuretics, may experience symptoms such as the excessive loss of bodily fluid. When fluid loss occurs, the amount of minerals (e.g., magnesium or potassium) in the blood stream rapidly decreases.
Additional, frequently prescribed medications that are associated with muscle cramps include:
- Donepezil, which is prescribed to Alzheimer’s patients
- Neostigmine and nifedipine, which are prescribed to high blood pressure patients
- Raloxifene, which is prescribed to osteoporosis patients
- Albuterol, which is prescribed to asthma patients
- Tolcapone, which is prescribed to Parkinson’s patients
- Statins, which are prescribed to high cholesterol patients
Factors such as nerve dysfunction, muscle fatigue, exercising in a hot environment, overexertion of the muscles while exercising, exercising without stretching beforehand, and poor blood circulation in the legs can also lead to muscle cramps.
Muscle Sprains And Strains
A muscle sprain or strain can also cause leg pain. A strain in the leg muscles occurs when tears and stretches develop in the muscle tissue. More specifically, making a sudden movement that forces a leg muscle to contract too quickly as well as stretching a muscle too far can lead to damaged muscle tissue and the onset of pain. In addition to causing intense pain in the leg region, this type of muscle damage also results in a tender and painful sensation when the strained region is touched or moved.
When a muscle sprain or strain has occurred, exerting the leg tends to increase the pain, while resting the leg alleviates it. Swelling of the muscle, bruising, difficulty walking, muscle weakness, and abnormalities in the structure of the muscle are also associated with a muscle strain. In cases of severe strains, there may be a complete loss of muscle movement.
Some cases of leg pain occur after a bone in the leg has become fractured. However, in order for a bone to actually break, it must have sustained a blunt force or trauma. In such cases, an individual may be able to easily identify and describe the cause of the fracture. There are certain conditions, however, that cause bones to weaken over time and this increases the risk of bone fractures. The symptoms of a fracture in the leg include swelling, severe pain, and visible deformities at the fracture site, in some cases.
Shin Splints (Medial Tibial Stress Syndrome)
A shin splint is characterized by swelling, intense leg pain, tenderness, and soreness, especially in the tibia or shinbone. This condition generally develops because of an injury or when tendons or muscle tissue surrounding the shinbone become inflamed. The pain may decrease temporarily when the leg is rested, but it usually increases with movement and becomes chronic over time if left untreated.
The most commonly diagnosed form of arthritis is osteoarthritis. This is a degenerative condition that mainly affects the joints and is characterized by the extensive degeneration of cartilage in the joints, such as the legs, arms, and knees. Cartilage is a shock absorber which ensures that joints glide smoothly and bones don’t become damaged by rubbing together. As time progresses, wear and tear can cause cartilage to become damaged, but blunt trauma or an injury can also cause damage to the cartilage. Serious cartilage damage may allow bones in the legs to rub against one another which can result in serious pain and inflammation as well as reduced joint flexibility. In addition, pieces of damaged cartilage may travel into the synovial fluid sac that surrounds the joint. Various treatment approaches are available for osteoarthritis patients, but cures for this condition have not been found.
Another common type of arthritis is rheumatoid arthritis, which develops when the body’s immune system becomes overactive and begins to attack the body’s joints. This autoimmune disease is more specifically described as the deterioration of the tissue that lines the capsules which encase joints due to an abnormal immune system response. This causes the protective lining to become inflamed and swollen. Rheumatoid arthritis can begin as minor joint damage, but if an individual does not receive proper treatment, this condition will eventually cause damage to vital organs.
A hamstring injury is typically caused by overextending one or more leg muscles. This leads to pain, tissue inflammation, and tissue damage. Intense pain is usually felt as soon as the injury occurs and it is most often felt in the lower region of the buttocks or the back of the thigh. Straining or overusing the hamstring are the main reasons that this type of injury occurs. More specifically, individuals who do not properly stretch before exercising or those who are normally sedentary and then spontaneously begin a vigorous activity program have an increased risk of experiencing a hamstring injury.
Myalgia is a condition that causes moderate to severe pain. In certain instances, the pain resolves on its own in a matter of days, but in other instances it may be bothersome for months. In addition to the legs, the pain that develops due to myalgia may be felt in any region of the body. It is believed that this condition is associated with extreme tension or stress, an injury, or overexerting the body. Myalgia pain generally occurs in one specific region as opposed to other conditions that often lead to widespread pain.
An underlying condition that may be the cause of leg pain in some cases is compartment syndrome. This serious condition is described as pressure build-up in different compartments in the body. The compartments include regions where several organs and tissue come together; leaving a space between them that consists of fascia (durable connective tissue). Compartment syndrome may develop after a minor injury has occurred, especially if the injury has caused fluid or blood to accumulate in a particular compartment because this places excessive pressure on the organs and tissue. When the injury occurs in the leg region, the result is intense leg pain. This condition can also cause serious damage to surrounding tissue. Furthermore, the loss of critical bodily functions may occur if the condition is not properly treated.
A form of bone cancer known as osteosarcoma is associated with bone pain, which often occurs in the legs. This disease tends to present itself during childhood or adolescence and is usually diagnosed before the age of 15. Factors that cause this disease have not been identified. Osteosarcoma patients generally experience bone pain, bone fractures, decreased mobility, swelling, redness at the tumor site, and tenderness. In addition, if a tumor develops in the leg, the patient may limp when trying to walk.
Nervous System-Related Causes Of Leg Pain
The lumbar region in the back as well as the sacral area in the tailbone contain specialized nerves that regulate sensory information for the legs. In general, when these nerves become damaged or irritated and inflamed the individual will develop leg pain as a result. Below are several known sources for neuropathic leg pain.
Sciatica is characterized as leg pain due to sciatic nerve inflammation. The pain occurs specifically in the legs in the back and not the front of the legs. In addition, sciatic pain along with tingling, numbness, or burning may be experienced in the lower regions of the back and buttocks. If leg pain develops because of sciatica, only one side is usually affected, the pain increases while at rest, an individual may begin to have trouble standing or walking, and the pain often becomes persistent. A herniated disc, spinal stenosis, isthmic spondylolisthesis, degenerative disc disease, sacroiliac joint dysfunction, and piriformis syndrome are conditions that commonly cause sciatic leg pain.
Peripheral neuropathy is another condition that typically develops due to nerve damage. It generally presents symptoms such as severe pain, tingling, or numbness in the extremities (e.g., legs). As the condition progresses, individuals will have an increasing level of difficulty trying to move around due to frequent muscle cramps. Motor nerve damage that occurs because of an injury is one of the main reasons that peripheral neuropathy develops. This type of injury may occur after an individual has fallen, fractured a bone, or experienced blunt trauma. Sometimes motor nerves become injured due to leading a sedentary lifestyle. A lack of exercise and physical activity can also disrupt the circulation in the body, which can lead to abnormal amounts of pressure being placed on the nerves in the extremities.
Diabetic Peripheral Neuropathy
Diabetic peripheral neuropathy is a form of nerve damage that is common in individuals who have diabetes. The complications that are associated with diabetes are believed to be the cause of this condition. Specific complications include metabolic aspects (e.g., high levels of blood glucose), autoimmune aspects (e.g., irritated or inflamed nerve bundles), neurovascular aspects (e.g., blood vessel damage), mechanical nerve bundle injuries (e.g., carpal tunnel syndrome), lifestyle aspects (e.g., smoking and an excessive consumption of alcohol), and genetics (e.g., a family history of nerve-related conditions). Individuals who have this condition do not always experience pain, but if pain does develop, it is typically felt in the extremities.
Shingles, also referred to as herpes zoster, is a painful skin rash that develops because of the varicella-zoster virus. This is the same virus that causes chickenpox. If a person develops or encounters someone who has chickenpox, the virus stays in the body from that point on. The virus can become reactivated in the nerves when an individual is an adult. This causes shingles. Shingles appears most often in adults with weak immune systems, which tends to develop as a result of injury, medication, or stress. The painful rash usually resolves on its own after a few weeks, but persistent neuropathic pain that is experienced after the rash has cleared is called post herpetic neuralgia.
Post-Laminectomy Syndrome (Failed Back Surgery)
Post-laminectomy syndrome is a rare pain condition that is characterized by unexpected pain that develops after a surgical procedure has been performed on the back. This syndrome is associated particularly with a form of back surgery called a laminectomy. In certain instances, the pain may extend to the legs. It is believed that this is due to unexpected nerve injury that occurred during the surgery.
Conditions Of The Veins And Arteries That Cause Leg Pain
Deep Vein Thrombosis (DVT)
Deep vein thrombosis is a condition that occurs when a blood clot, which is also called a thrombus, develops in a vein in the leg. It is believed that most blood clots begin to form when an individual maintains a seated position for extended periods of time. For example, traveling for several hours by plane or in a car significantly increases the risk that blood clots will develop. However, there are additional conditions that affect blood circulation and increase the likelihood of blood clot formation. The symptoms of deep vein thrombosis are swelling and intense leg pain, generally close to the feet or ankles. Sometimes, this condition develops in the absence of symptoms.
Peripheral Artery Disease (PAD)
Peripheral artery disease is described as the blockage or constriction of blood vessels that extend into the extremities (e.g., legs). This disease may develop in any part of the body, but most often occurs in the legs. Constricted blood vessels may develop because of atherosclerosis—a condition in which the gradual build-up of fat deposits clogs the arteries. Subsequently, this type of constriction often causes leg pain, especially in the calf or thigh during movement. Most of the time, resting stops the pain.
Treatments For Leg Pain
There is a vast amount of underlying conditions that lead to the development of leg pain. Therefore, it is imperative to discuss an event that may have led to it as well as details regarding medical history with a physician. This helps ensure that the appropriate diagnosis and treatment option will be recommended. Conventional treatment methods such as pain relievers may be recommended for individuals whose leg pain is mild and is not hindering their ability to move or engage in daily activities.
Common pharmacotherapy methods that are used to treat pain include non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, naproxen, and aspirin, or oral analgesics such as acetaminophen. There are side effects associated with the use of NSAIDs such as gastrointestinal problems, internal bleeding, and ulcers. Therefore, NSAIDs should only be taken temporarily to relieve leg pain and not for chronic cases.
Antidepressants have also been commonly prescribed for chronic pain. Research indicates that antidepressants are effective at treating pain, but the data is limited regarding whether they effectively relieve leg pain. Commonly prescribed antidepressants are amitriptyline, clomipramine, and doxepin. It is believed that these medications block the reuptake of neurotransmitters such as serotonin and norepinephrine, thereby relieving pain. In addition, two new types of antidepressants that cause fewer side effects are being recommended to patients with chronic pain. These include fluoxetine, fluvoxamine, and citalopram, which are selective serotonin reuptake inhibitors (SSRIs); and desvenlafaxine, venlafaxine, or duloxetine, which are serotonin and norepinephrine reuptake inhibitors (SNRIs). According to physicians, the newer medications are currently preferred. Chronic pain may often lead to social withdrawal, a state of hopelessness, or depression. These symptoms can be treated with SNRIs or SSRIs.
If over-the-counter medications such as NSAIDS and antidepressants do not effectively reduce pain, a physician may recommend one of the following opioid medications in order to help manage the pain: oxycodone, morphine, codeine, or tramadol. This class of drugs is particularly effective at relieving chronic leg pain. The ability of opioids to reduce pain is attributed to the manner in which they bind to opioid receptors in the brain. Research has demonstrated that opioids provide short-term relief of intense, sudden pain. The side effects that may occur after taking opioids on a regular short-term basis include sweating, dizziness, sexual impotence, and constipation. However, the prolonged consumption of opioids may lead to drug abuse, dependence, or even overdose.
Musculoskeletal Leg Pain Treatments
Muscle relaxants are a form of medication that physicians frequently prescribe for leg pain. There are two categories of muscle relaxants: antispastic and antispasmodic. Medications that are antispasmodic such as non-benzodiazepines and benzodiazepines decrease the frequency of muscle spasms that occur, and in doing so, decrease pain. Medications that are antispastic such as baclofen and dantrolene also decrease muscle spasticity in the legs, but research that demonstrates the effectiveness of this type of medication is limited.
Another form of muscle spasm treatment is Botox injections. Botox is composed of purified botulinum neurotoxins. Clostridium botulinum bacteria produce these enzymes which are toxic to muscle tissue and cause temporary paralysis. It is postulated that Botox has the ability to relieve pain by hindering nerve impulses that have become overactive, while disrupting neurotransmitter release, especially those that regulate pain sensations. Randomized, controlled clinical trials have repeatedly been conducted in order to evaluate the effectiveness of using Botox to treat pain. The findings have indicated that pain relief is usually experienced approximately three weeks after an injection in comparison to a placebo group. However, additional data is needed regarding the use of Botox to treat leg pain that occurs because of muscle spasms.
Treatments For Nervous System-Related Leg Pain
A prescription medication called gabapentin is an anticonvulsant that is sometimes recommended for leg pain that occurs because of a neuropathic problem. The exact mechanism of this medication is not well understood, but it has been postulated that anticonvulsants increase the levels of glutamate and gamma-aminobutyric acid (GABA) in the body. Furthermore, this appears to either have an effect on ion-channels or enhance the activity of non-synaptic GABA, both of which appear to produce pain relief. Currently, additional research regarding using anticonvulsants to treat leg pain is needed.
A minimally invasive chronic pain treatment that has been utilized for a variety of conditions including leg pain is known as biofeedback training. Biofeedback was developed based on the concept that the way individuals think can influence processes in the body and that this may occur consciously or subconsciously. For instance, painful experiences can put extra stress on the body as well as the mind. Furthermore, stress is associated with physiological changes in the body such as muscle tension and an increase in blood pressure, respiration, and heart rate. Symptoms such as muscle tension or heightened respiration can exacerbate pain and this process becomes a feedback loop that makes it difficult for an individual to experience long-term pain relief without some form of intervention. Biofeedback provides an opportunity to break the stress-pain cycle.
This technique involves teaching patients how to reduce pain by regulating different physiological processes through visual cues. After the patients have been successfully trained, they can begin to recognize triggers that cause or increase their pain. This allows patients to have a certain level of control of their body’s response to pain, and in some cases, this leads to a significant decrease in chronic pain flare-ups. More specifically, during biofeedback training, specialized instruments that are designed to measure different autonomic functions such as brain activity, respiration, heart rate, or muscle tone are connected to the patients. The readings are displayed on a computer screen so the patients can view them in real time. Patients are trained to regulate their internal processes through coping skills and relaxation along with the help of the visual readings and techniques that trained biofeedback technicians teach them.
The following measurement techniques are commonly used for training purposes:
- Electrocardiogram (ECG), which measures heart rate and changes in heart rate
- Electromyography (EMG), which measures muscle tension
- Galvanic skin response (GSR), which measures the accumulation of moisture on the surface of the skin
- Electroencephalography (EEG), which measures brain wave activity
- Thermal feedback, which measures skin temperature
Neuropathic leg pain may also be relieved by using capsaicin skin patches. Capsaicin is the main component of chili peppers and it binds to nociceptors that are located in the skin. When nociceptors become excited, they stimulate sensory neurons, which cause increased sensitivity and symptoms such as burning, itching, or pricking feelings, followed by a reduction in sensitivity. When the application of the skin patch is repeated, continuous desensitization of the neuropathic leg pain will eventually occur. Clinical research has demonstrated strong evidence regarding the effectiveness of using capsicum in comparison with a placebo to treat leg pain that has been caused by sciatica.
Epidural steroid injectionsare also commonly administered to patients suffering from neuropathic leg pain. The spinal cord is surrounded by what is known as cerebrospinal fluid (CSF). This fluid protects nerve bundles in the spinal cord. The spinal cord is encased within the spinal canal and held firmly in place by a robust membrane. The area just outside of this membrane, called the epidural space, is the region that steroids are injected into. The roots of the irritated nerves are located in this area and delivering the steroid to the roots leads to the alleviation of pain. Steroids are generally only administered to regions where significant inflammation is present as a means of reducing the amount of medication that healthy nerve roots and tissue will be exposed to.
A sciatic nerve block is a treatment approach for individuals who are experiencing debilitating sciatic nerve pain in the leg. Surgery is not necessary for a sciatic nerve block and this procedure is minimally invasive. Anesthesia is administered to the nerve bundle of the sciatic nerve, which blocks the transfer of pain signals to the brain and spinal cord. Physicians have the advantage of using several methods to deliver anesthesia to the sciatic nerve bundle due to its large size. Patients have generally reported experiencing immediate pain relief after undergoing this procedure.
A similar treatment approach is a sacroiliac joint injection. The sacroiliac joint is a large structure that connects the spine to the hips. More importantly, it helps the spine bear the weight of the limbs and the upper body. A sacroiliac joint injection involves administering medication to the area that surrounds the fibrous capsule membrane. Local anesthesia is applied to the skin and then an imaging device such as an X-ray or fluoroscope is used to guide the thin needle that is inserted into the vertebral space near the sacroiliac joint. Contrast dye is also injected to help ensure that the needle will be properly placed before the steroids are injected and to make sure that the medication will be appropriately distributed to the targeted region. The steroids are then injected into the areas where the largest amount of inflammation was observed. Clinical trials have shown that injecting steroids into the tissue surrounding the joint or directly into the sacroiliac joint provides patients with more pain relief than placebo injections. Furthermore, the effects of the injections were reported to last for at least one month.
Radiofrequency ablationis another effective procedure that is minimally invasive. This technique entails introducing thin probes into the associated spinal nerves through the skin. The probes administer electro-thermal impulses to the nerves in order to destroy particular portions that transmit pain signals.
For patients whose leg pain occurred after a failed attempt at back surgery, the lysis of adhesions procedure may be helpful. In certain instances, back surgery can lead to the formation of scar tissue on spinal nerves. In actuality, spinal surgeries cause excessive scarring in many cases. Typically scar tissue begins to grow in the spaces between the targeted vertebrae and this results in the reoccurrence of the pain the surgery was meant to resolve or pain in additional regions in the body. Moreover, the development of scar tissue leads to the compression of spinal nerves as well as inflammation and swelling. The procedure involves the use of imaging techniques to help guide the placement of a needle and catheter into the scar tissue in order to facilitate the injection of medication that dissolves or breaks the scar tissue into small pieces that the body can excrete. An anesthetic may also be injected to reduce pain as well as steroids that decrease inflammation.
In rare cases, when leg pain does not decrease after pain medication or injections have been utilized, spinal cord stimulation may be recommended. This procedure entails implanting electrodes into the tissue that surrounds peripheral nerves that are responsible for pain and then administering a mild electrical current which disrupts the pain signals. However, this procedure is completed in two stages. The first stage involves a trial period in which a patient is implanted with temporary electrodes and receives stimulation for approximately one week. This trial period provides an indication of whether or not peripheral nerve stimulation will effectively reduce the patient’s pain. If the trial phase is not effective, the temporary electrodes can easily be removed and then alternative treatment methods can be discussed. If the trial period does provide some pain relief, then the second stage will involve surgically implanting permanent electrodes in the region of the body where the affected nerves are located.
One type of alternative treatment for leg pain is acupuncture, which is a method that originated from traditional Chinese medicine. The technique entails inserting needles in areas of the body where discomfort and pain is experienced as well as other regions responsible for the pain. The pattern in which the needles are strategically placed leads to the reduction of pain, stiffness, muscle spasms, and inflammation. Acupuncture also causes the body to release endorphins, which are hormones that decrease pain sensations. Patients who have not experienced pain relief from conventional treatments may decide to undergo acupuncture. For some people, this type of therapy is more effective than other commonly used treatments. In addition to undergoing traditional acupuncture, which utilizes needles, a patient may also receive electroacupuncture, which uses electrical pads or electrically charged needles; laser acupuncture, which involves the use of laser beams; or manual acupuncture, which involves the use of the fingers.
Another form of non-invasive therapy for sciatica-related leg pain is calledtranscutaneous electrical nerve stimulation (TENS). This type of stimulation may be performed along with acupuncture. The procedure involves placing electrodes on the skin in order to deliver bursts of electrical current directly to the peripheral nerves. Research is beginning to provide evidence that supports using TENS to treat chronic pain. However, it is limited so additional studies will need to be performed.
Persistent leg pain is a frequent complaint among adults. The underlying causes of leg pain are numerous. Factors such as injuries, spinal stenosis, muscle cramps or spasms, osteoarthritis, muscle sprains or strains, nerve damage, bone fractures, failed back surgery, or diabetes-related complications contribute to the occurrence of leg pain. Symptoms that may also develop include muscle weakness, numbness, radiating pain, cramping, tingling, muscle spasms, stiffness, and sensitivity to pressure or touch.
Accurately diagnosing the pain source is critical to ensure that the appropriate form of treatment will be recommended. A thorough examination is imperative as dangerous health problems such as internal bleeding or blood clots could be the cause of the leg pain. Various treatment methods are available that effectively reduce leg pain. These include conventional treatments such as pain relievers, biofeedback training, steroid injections (e.g., sciatic nerve blocks), and spinal cord stimulation. A physician will be able to recommend the optimal method of treatment after a proper diagnosis has been made.
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