Leg Pain Causes

Most of us have experienced some type of leg pain at least once in our lives. More often than not, the leg pain goes away on its own, requiring little or no intervention, but sometimes the pain can persist or increase in intensity and become a source of distress. 

In this article, we will explore the various causes of leg pain, discuss possible treatments and when it is best to seek prompt medical attention. In order to understand the causes of leg pain fully, this article will first explain the anatomy of a human leg.

Anatomy of the leg

The human leg, also known as the “lower limb”, is the area between the knee and the ankle.¹ Firstly, there are two major bones found in the leg, known as the tibia and the fibula. Out of these two, the tibia is known as the “shin bone” and is the larger bone, hence supporting most of our weight. 

Next, if we take a closer look at the muscles found in the leg, they can be divided into three compartments; the anterior, posterior and lateral compartments. There are groups of muscles found in each compartment, and the smallest of these is the lateral one, which only contains two muscles. 

These muscles need to be provided with oxygenated blood in order to function, and this blood is supplied via the anterior and posterior tibial arteries. There are also veins present, which are responsible for the drainage of the blood from the leg, and the veins that drain the deeper muscles are known as the fibular and tibial. 

Nerves are also an important part of the leg anatomy and the main nerves that supply the leg region are known as the tibial, fibular/peroneal, and saphenous nerves. 

Common leg pain causes

Muscular causes

Muscular injury is a common cause of leg pain, and these types of injuries usually occur during sports or exercise, but they can even occur during mild physical activity. These injuries can occur from either a sudden fall or blow, or they can occur gradually over time as the “overused” muscle undergoes excessive wear and tear. The result of sudden injury can cause a sprain, strain or contusion and the gradual wear and tear can result in tendinitis and bursitis.² 

Tendons are cord-like structures which help tether muscle to bone, and when they become inflamed due to injury, the condition is called tendonitis. Bursitis occurs when the bursa, which is a sac filled with fluid found between muscles and bones, becomes inflamed. Both tendonitis and bursitis can cause a considerable amount of leg pain and tenderness, even at rest.

Sprains and strains³ are also common causes of leg pain, and they involve stretching and/or tearing of the ligaments, muscles and tendons in the leg. Sprains frequently occur in the ankles or knees after a fall or sudden twisting motion involving these joints; strains are commonly seen at the back of the legs and commonly occur during sports. Along with leg pain, there may also be swelling, inflammation and muscle spasms.

Often, the muscles in the legs can suddenly and involuntarily contract/tighten, causing pain in the legs ranging from mild to severe; these contractions are called spasms or cramps.⁴ These cramps occur multiple times and last from a few seconds to several minutes, and the muscles involved in the cramp can feel hard to the touch. There are several causes of muscle cramps which include:

• Dehydration
• Overused or fatigued muscle
• Too little stretching before exercise
• Restricted blood supply
• Sitting for a prolonged time

There are many reasons for leg cramps, and sometimes the exact cause might be unknown (idiopathic). They occur in all age groups and are considered very normal. 

Skeletal causes⁵

Leg fractures (any break/crack in the leg bones) are also a common cause of leg pain. A fracture can occur after a fall, a motor vehicle injury, during sports or in other similar situations and the associated symptoms can include extreme pain, swelling, tenderness, bruising and an inability to walk or bear weight on the affected leg. 

Another less common type of fracture is a stress fracture, and these are small, less obvious breaks/cracks in the bone. Stress fractures can cause leg pain, and this pain typically gets worse over time since these fractures are associated with the gradual wear and tear of the affected bone. This gradual wearing down of the bone usually occurs during sports such as ballet, dancing, basketball and running.

It can also occur in people with underlying health conditions such as osteoporosis (decreased density of the bone), rheumatoid arthritis or diabetes. Along with the gradually increasing leg pain, there may also be swelling, tenderness and, eventually, an inability to walk. 

Sometimes, leg pain can be associated with arthritis, and this condition affects millions of people in the UK⁶, in all age groups. If the knees are affected, it can cause knee and associated leg pain along with other symptoms such as joint stiffness, inflammation and decreased movement. 

Vascular causes

Occasionally, there can be a build-up of fatty plaque in the arteries of the legs, which can lead to decreased blood supply to the affected leg. This condition is called Peripheral Artery Disease, and it occurs particularly in diabetes, high cholesterol levels, smoking and high blood pressure individuals. The signs and symptoms noticed in the condition are leg pain which gets better after rest, pain radiating to the thigh, calf, buttock or hip, cool and shiny skin in the affected leg and possibly the development of ulcers or sores. 

Another disease known as Deep Vein Thrombosis (DVT), is when there is a blood clot present in the vein; this is a serious disease which requires immediate intervention. It can occur after prolonged periods of rest, obesity, smoking, taking the oral contraceptive pill or a previous episode of DVT. Usually, only one leg is affected, and there is throbbing, swelling and warm, darkened skin which is seen around the affected leg. 

Nerve related causes⁷

Leg pain can also be caused due to a complication with the nerves which travel down the spine to supply the legs. This condition is known as sciatica, and it can affect many people. This pain can range from mild to severe and can travel from the spine all the way down the leg to the foot. There may also be associated pins and needles, numbness, burning or muscle spasms in the affected leg. 

Very similar to sciatica is another disease known as peripheral neuropathy. This occurs due to some damage in the nerve, and the symptoms caused are very similar to sciatica. It is important to seek medical attention if any of these symptoms are experienced so that they can be properly diagnosed and treated. 

Lifestyle factors

Although leg pain can be worrying, sometimes it can be experienced due to lifestyle choices which can easily be changed. As discussed earlier, too much physical activity, such as extreme sports, may lead to wear and tear in the body, which can cause leg pain. On the other hand, physical inactivity can also lead to leg pain and stiffness. 

Diagnosis and evaluation 

It can be deduced from the discussion above that leg pain is usually a symptom of a medical condition and not a disease in itself. Hence, it is imperative to provide a detailed and accurate history to your doctor and to undergo a thorough physical examination. 

After this, the doctor might order further blood tests or possibly even imaging tests such as an X-ray, MRI or ultrasound. 

Once the diagnosis is confirmed, plans can be made for further medical treatment. 

Treatment and prevention

Treatment of leg pain largely depends on the underlying health condition, but minor leg injuries, such as sprains and strains, can be managed effectively at home. There are four simple steps which need to be followed; this is called the RICE⁸ method:

• Rest: try not to move your leg too much
• Ice: use an icepack to ice the affected area every 15 minutes
• Compression: bandage the area firmly but not too tightly 
• Elevate: keep the affected leg raised as much as possible 

Minor leg pain can also be managed by over-the-counter medication such as paracetamol and ibuprofen. These drugs also have anti-inflammatory effects, which might be helpful for any leg inflammation. 

Further treatment might be needed according to the underlying condition, and this may involve more medication, physiotherapy or even surgery. 

Lifestyle factors can cause leg pain, as seen above, and if some lifestyle modifications are brought about, some leg pain can be prevented. Obesity, a poor diet low in fruits, vegetables and essential vitamins and minerals, can cause leg pain and cramps. Thus, a healthy, varied diet is of utmost importance. It is also essential to always warm up and stretch properly before exercising and practice regular gentle exercise. Extreme sports should be conducted in variation and preferably under continued medical guidance. 

Summary

In conclusion, leg pain is a very common phenomenon and is usually not a cause for major concern. Minor sprains, strains, and cramps are everyday occurrences and do not usually require any treatment.

However, any persistent pain or debilitating pain should always be followed up by a visit to the doctor. This type of pain can hint at an underlying condition that might need immediate medical intervention. 

Care should be taken whilst exercising, and a healthy lifestyle may also help decrease the incidence of leg and other types of minor pain.