Experiencing one leg swelling can often be caused by a blood clot located in a deep vein, also known as deep vein thrombosis (DVT). Other common causes of a swollen shin or calf include trauma from an injury that can lead to bruises, fractures, or sprains. Read below for more information on causes and treatment options.
8 most common cause(s)
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Symptoms of swelling in one lower leg
Swelling, also called edema, is the result of fluid buildup that gets trapped in your body's tissues. Buildup can occur when there is obstruction and fluid cannot properly flow and/or drain. However, fluid buildup can also occur when an area of the body becomes inflamed, injured or damaged. The small blood vessels in the body begin to leak fluid. Moreover, the body can bring in white blood cells to repair the damage, and more fluid follows. Depending on the cause, the swelling can be generalized and occur throughout the body, or localized and only affect a specific part of the body.
Common characteristics and other symptoms of a swollen lower leg
The legs are gravity-dependent. Swelling localized to one leg is often obvious and easy to identify. One leg will appear larger than the other and may be accompanied by the following symptoms as well:
- Pain
- Redness or warmth of the lower leg
- Pitting: The skin dimples or dents after pressing on the affected area for a few seconds.
- Cramping or soreness
- Feeling of heaviness
- Stretched or shiny skin
- Stiffness
- Limited range of motion
Swelling in only one leg and not the other can be a sign of a serious underlying condition that requires prompt attention. If you notice any of these symptoms, make an appointment with your physician as soon as possible in order to receive appropriate care.
Causes of swelling in one lower leg
Causes of swelling in one lower leg can vary, all related in some way to obstruction. Other causes include those that are systemic, inflammatory, and environmental.
Obstructive
As stated above, fluid buildup can occur in the case of obstruction. Obstructive causes of swelling in one lower leg are often related to clotting of the blood. When a blood clot forms in the deep veins of the lower leg (deep vein thrombosis or DVT), it obstructs blood flow and can result in leg swelling and pain. There are different categories of how blood clots can form including:
- Hematologic: Bleeding disorders and medical conditions such as cancer that affect the way different components of the blood function can result in blood clots.
- Immobility: When the leg is immobile for long periods of time, such as after surgery or traumatic injury that requires casting, the muscles do not contract normally to help blood circulate; thus, blood flow is disrupted and blood clots can form.
Fluid leakage resulting in a swollen lower leg
In the case of fluid leakage, there are three general mechanisms that can occur that result in fluid buildup in the surrounding tissues of the leg:
- Excessive force or pressure inside the blood vessels
- A force external to the blood vessel that can cause fluid to be drawn out
- Damage or destruction to the blood vessel wall leading to fluid loss
The exact causes behind these mechanisms can be broad, ranging from benign to life-threatening, so it is important to make an appointment with your physician in order to get appropriate care.
Systemic
Systemic-related causes of lower leg swelling may include those listed below.
- Circulatory: Problems with the heart and its ability to pump effectively will cause blood to back up in the lower body. This causes excessive pressure in the blood vessels and leads to damage and further leakage of fluid into the body's tissue.Furthermore, if the veins of the circulatory system are weakened or damaged, the swelling will occur in a similar manner. This more commonly causes swelling in both legs (bilateral).
- Lymphatic: The lymphatic system is the body's natural way of clearing excess fluid from tissues.It is composed of multiple nodes and vessels, that when damaged, can cause swelling all over the body, especially in the lower leg.
- Kidney: The kidney is a potent regulator of bodily fluid because it is responsible for filtering and clearing the blood. Without the kidney, filtrate such as proteins, electrolytes, and toxins can remain in the blood and act as forces that draw fluid out. In most cases, kidney problems result in swelling of both legs and usually does not affect only one leg.
Inflammatory
Inflammatory causes for swelling in one lower leg may include:
- Arthritis: Arthritis is a general term for multiple conditions that cause painful inflammation and stiffness of the bones and joints. Arthritic processes that affect the knees and ankles can cause irritation that often leads to injury. Furthermore, arthritis in the joints of the lower extremitiespredisposes people to inactivity, making swelling even more likely.
- Infection: Both superficial infections of the skin and deep tissueinfections of the lower leg can result in swelling. One type of deep tissue infection, called necrotizing fasciitis, can spread quickly and destroy tissue, resulting in a life-threatening illness that requires immediate care.
Environmental
Environmental causes can range from lifestyle habits to certain exposures listed below.
- Smoking: Smoking can affect blood clotting and circulation, increasing the risk of deep vein thrombosis.
- Medication: Swelling in one lower leg can be a side effect of many medications that treat common conditions such as high blood pressure, diabetes, and menopause. However, this usually causes swelling in both legs rather than just one.
- Diet: Diets high in sodium can cause an overload of the body's filtering mechanisms. The extra salt in the blood will cause fluid to be drawn out from the vessels, causing swelling. Furthermore, obesity can increase the pressure in the veins of the lower leg causing leakage and fluid buildup.
This list does not constitute medical advice and may not accurately represent what you have.
Repetitive strain injury of the calf
Repetitive strain injury of the calf is caused by consistent repetitive use.
Rarity: Uncommon
Top Symptoms: lower leg numbness, calf pain from overuse
Symptoms that always occur with repetitive strain injury of the calf: calf pain from overuse
Symptoms that never occur with repetitive strain injury of the calf: recent calf injury, severe calf pain
Urgency: Self-treatment
Stress fracture of the foot (marching fracture)
A "March" stress fracture of the foot is named because it's sometimes linked to soldiers marching for a long time. This foot fracture happens because of prolonged stress or weight-bearing.
You should go to a primary care doctor or orthopedist, who might take a CT or MRI to help in diagnosis. Treatment involves reducing movements for 6-12 weeks.
Rarity: Rare
Top Symptoms: constant foot pain, foot pain from overuse, pain in one foot, pain when touching the foot, pain in the top of the foot
Symptoms that always occur with stress fracture of the foot (marching fracture): foot pain from overuse, constant foot pain
Urgency: Primary care doctor
Shin bruise
A bruise is the damage of the blood vessels that return blood to the heart (the capillaries and veins), which causes pooling of the blood. This explains the blue/purple color of most bruises. Bruises of the shin are common given the location of the shin.
You can treat this at home with R.I.C.E - rest (exercise as tolerated), ice (10-20 minutes at a time), compression (this is pretty optional), and elevation (put your feet up to help blood flow back to the heart using gravity).
Rarity: Uncommon
Top Symptoms: shin pain from an injury, shin injury, pain in one shin, shin swelling, shin bruise
Symptoms that always occur with shin bruise: shin injury, shin pain from an injury
Urgency: Self-treatment
Jones fracture (broken foot)
A Jones Fracture is a fracture of a bone on the outside of the foot (called the fifth metatarsal). A Jones fracture can be either a stress fracture (a tiny hairline break that develops with time), or a sudden break due to trauma. This can result in pain, swelling, and tenderness on the outside of the foot.
You should visit your primary care physician or an urgent care today. Until then, the RICE method of care should be performed: rest (stay off the injured foot), ice (apply an ice pack to injured area), compression (an elastic wrap to control swelling), and elevation (raising the foot slightly above the level of the heart to reduce swelling). A doctor may perform a X-ray and put a cast or splint on the foot.
Rarity: Rare
Top Symptoms: difficulty walking, constant foot pain, pain in one foot, foot bruise, foot injury
Symptoms that always occur with jones fracture (broken foot): foot pain from an injury, pain when touching the foot, constant foot pain, pain in the front half of the foot, pain in the outside of the foot
Urgency: In-person visit
Fracture of the talus
A talus fracture is a break in one of the bones in the ankle called the "talus." This type of injury oftens occurs during a high-energy event, such as a car accident or fall.
You should seek immediate medical care at an urgent care clinic or ER. This type of fracture generally involves surgical treatment to repair the break.
Rarity: Ultra rare
Top Symptoms: pain in one foot, swollen ankle, severe foot pain, pain in one ankle, ankle pain from an injury
Symptoms that always occur with fracture of the talus: pain in one ankle, ankle pain from an injury
Urgency: Hospital emergency room
Deep vein thrombosis
A deep vein thrombosis (DVT) occurs when a blood clot forms in a vein deep in the body, usually in the lower leg or thigh. DVT can cause swelling, pain, and redness in the affected leg. Some of the risk factors for developing DVT include obesity, pregnancy, cancer, surgery, and previous history of blood clots.
You should consider calling your primary care or urgent care provider. Deep vein thrombosis can be evaluated with a review of your symptoms, a physical exam, and an ultrasound. A blood test may also be performed. Once diagnosed, DVT can be treated with blood-thinning medication, which is usually taken for three months.
Rarity: Uncommon
Top Symptoms: fever, thigh pain, upper leg swelling, calf pain, butt pain
Urgency: Hospital emergency room
Compartment syndrome
Acute compartment syndrome describes the damage done to certain muscle groups of the arms or legs after a traumatic injury.
All of the long muscles are bundled into sections – "compartments" – by the white sheets of strong, tough connective tissue called fascia. If something interferes with circulation so that blood flow is trapped within the compartment, pressure rises because the fascia cannot stretch. This causes serious damage to the muscles and other tissues within the compartment.
Acute compartment syndrome is caused by a broken bone; a crush injury; burns, due to scarred and tightened skin; and bandages or casts applied before an injury has stopped swelling.
Symptoms can rapidly intensify. They include severe pain and tightness in the muscle; tingling or burning sensation; and sometimes numbness and weakness.
Acute compartment syndrome is a medical emergency which can result in loss of the limb. Take the patient to the emergency room or call 9-1-1.
Diagnosis is made through patient history and physical examination.
Treatment involves hospitalization for emergency surgery and, in some cases, skin graft.
Rarity: Rare
Top Symptoms: arm numbness, hand numbness, foot numbness, pain in one leg, thigh numbness
Urgency: Hospital emergency room
Calf strain
A strain, commonly called a "pulled muscle," is when a muscle becomes overstretched, and microscopic tears occur. A calf strain happens when one of the muscles on the back of the lower leg is pulled.
You can safely treat this condition on your own. A muscle strain can be treated with rest, ice, compression, and pain medication.
Rarity: Common
Top Symptoms: pain in one calf, moderate calf pain, calf pain, sports injury, soccer injury
Symptoms that always occur with calf strain: pain in one calf
Urgency: Self-treatment
Calcaneus fracture
Calcaneus fractures occur when a force that is stronger than the calcaneus itself is applied to the bone. s are rare, although they are the most commonly fractured tarsal bone. These fractures can occur in many different situations, but most commonly occur in high-energy trauma situations such as car crashes or falls from heights (ex. a ladder or roof).
Symptoms generally depend on the severity of the fracture but usually include significant pain, swelling, bruising, numbness, limited mobility, and limping, among others.
Calcaneus fractures can lead to long-term deformity and require good follow-up and management. Treatment options include methods to reduce pain and restore function through surgery or physical therapy.
You should seek immediate medical care at an urgent care clinic or ER. A doctor will confirm the diagnosis with an X-Ray. This condition can be treated non-surgically with a cast. However, if the bones have shifted out of place, surgery may be needed.
Ankle sprain
A foot sprain means there is damage to ligaments within the foot. The term "sprain" specifically refers to overstretching or tearing of ligaments – the strong, fibrous bands of tissue that hold the bones together within the joints.
Foot sprains are usually sports or dance injuries. Any sort of running movement that involves sudden stops, starts, and twisting can lead to a foot sprain. Suddenly getting the foot caught while walking or running can wrench the ligaments and cause a sprain.
Symptoms include swelling, bruising, and pain in the affected foot, especially with weight bearing.
If symptoms do not resolve quickly, or seem to get worse instead of better, a medical provider should be seen to make sure no fracture is involved.
Diagnosis is made through physical examination and imaging such as x-ray, CT scan, ultrasound, or MRI.
Treatment is usually conservative and involves rest to allow healing; nonsteroidal anti-inflammatory drugs for pain; elevating the foot to improve circulation; and wrapping the foot with an Ace bandage or wearing a special boot for support.
Rarity: Common
Top Symptoms: pain in one ankle, ankle pain from an injury, swollen ankle, bruised ankle, ankle twisting
Symptoms that always occur with ankle sprain: pain in one ankle, ankle pain from an injury
Urgency: Phone call or in-person visit
Swelling in one lower leg treatments and relief
Treatment for obstructive causes of swelling in one lower leg involves prevention of the formation of blood clots. There are several medications that work to thin the blood, break up clots, and filter clots that can break off and travel keeping them away from the lungs.
Medical treatments
Systemic causes of calf swelling are often treated with medication. Your physician may suggest:
- Diuretics: These medications,also known as "water pills," increase the water and salt your body excretes in the urine. This strategy helps reduce the fluid trapped in the body and your calves.
- Anti-inflammatory medications: Your physician may prescribe this type of medication to combat arthritic processes that are causing swelling.
At-home treatments
Fortunately, swelling in the calves can be mitigated by many strategies and remedies you can perform at home:
- Activity: Moving your legs and staying active can help pump any excess fluid pooling in the legs back toward your heart. Talk to your physician about exercises you can do at home in order to keep moving.
- Elevation: Place your legs above the level of your heart as much as possible. Elevating the legs during sleep can help significantly with calf swelling.
- Compression: Your physician may prescribe compression stockings for your legs. These garments keep pressure on your limbs to prevent fluid from collecting in the tissue. See this photo for an example of compression stockings and how they work.
- Protection: Keep your swollen calves clean and free from injury. Dry, cracked skin is more prone to scrapes, cuts, and infection.
- Dietary changes: Reducing salt intake, losing weight and quitting smoking can be an important step in reducing your swelling.
Here are some over the counter treatment that might help:
- Anti-inflammatory Medication: For pain relief and to reduce swelling, consider ibuprofen (Advil) or naproxen (Aleve).
- Compression Stockings: To help manage and reduce swelling, compression stockings can be very beneficial.
- Elevation Pillows: When resting, elevating your leg above heart level can reduce swelling. Consider an elevation pillow designed for this purpose.
Seek immediate medical attention in the emergency room or call 911 for the following
If you experience the items below, this can signify that a clot causing a deep vein thrombosis that has traveled to the lungs in a condition called a pulmonary embolism (PE):
- Sudden-onset swelling in one leg associated with pain
- Shortness of breath
- Chest pain
A pulmonary embolism is a life-threatening emergency that requires immediate attention.
FAQs about swelling in one lower leg
Why is the swelling in only one leg?
The swelling is localized to one leg due to obstruction of a deep vein in the leg or because of an infection or other inflammatory condition specifically affecting that extremity.
What tests are usually performed for swelling in one lower leg?
One test your physician may perform is an ultrasound of the affected leg. An ultrasound is a device that sends sound waves through the tissues of the leg and converts the sound waves into an image on a screen. Your physician will be able to visualize a blood clot if it is present.
Can a clotting disorder be inherited?
Yes, clotting disorders can be inherited. Be suspicious of an inherited clotting disorder if you and other members of your immediate family have experienced blood clots or complications of blood clots such as pulmonary embolism or multiple miscarriages.
Can I travel with swelling in one lower leg?
It is not advisable to travel with swelling in one lower leg. Traveling, especially for a long flight or drive, can cause increased disruption of blood flow in the lower leg. The muscles contract less and can further exacerbate a possible clot in the leg that is causing the swelling.
What can I do to prevent immobility in my lower leg on long flights or drives?
Moving as much as possible during a flight can help reduce periods of prolonged immobility. For example, getting up to go to the bathroom or walking up and down every two hours can go a long way in keeping the body active. If you cannot get up, perform seated exercises such as ankle circles, leg raises, or foot/calf pumps in order to prevent immobility. Avoid placing hand luggage in places that restrict movement of the legs and wear loose, comfortable clothing.
Questions your doctor may ask about swelling in one lower leg
- Have you ever been diagnosed with diabetes?
- Are you having any difficulty walking?
- What is your body mass?
- Do you have high blood pressure?
Self-diagnose with our free Buoy Assistant if you answer yes on any of these questions.
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References
- Sloane PD, Baldwin R, Montgomery R, Hargett F, Hartzema A. Left-Sided Leg Edema of the Elderly: A Common Variant of the Iliac Compression Syndrome. Journal of the American Board of Family Medicine. 1993;6(1):1-4. JABFP Link
- What You Should Know About Swelling in Your Legs. Cleveland Clinic. Published July 13, 2015. Cleveland Clinic Link
- Leg Swelling. Mayo Clinic. Published January 11, 2018. Mayo Clinic Link
- Deep Vein Thrombosis (DVT). Mayo Clinic. Published March 6, 2018. Mayo Clinic Link
- Group A Streptococcal (GAS) Disease. Centers for Disease Control and Prevention. Updated October 18, 2018. CDC Link
- Immobility, Circulatory Problems and Deep Vein Thrombosis (DVT). World Health Organization. WHO Link