Will Swelling Under a Cast Go Away on Its Own? How to Reduce Swelling Under a Cast

A medical professional is wrapping a patient's wrist with a white bandage that has red lines along the edges.
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When you're dealing with a broken bone and find yourself rocking a cast, you might notice that the area surrounding the injury starts to swell. This can often be uncomfortable and may leave you worried about what happens next. Should you let the swelling subside on its own or take action to reduce it?

While mild swelling is generally part of the healing process, abnormal swelling can indicate complications. In this blog post, we'll discuss the cause of swelling under a cast, how to reduce it, and whether it'll go away on its own.

What Causes Swelling in a Cast? 

A close-up of a person's arm, revealing a white cast on the forearm and hand, with the arm supported by a navy-blue sling.
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Swelling is a natural response to injury, and fractures are no exception. When a bone breaks, the nearby tissue, blood vessels, and nerves may become damaged. 

This swelling, medically known as edema, is your body's way of delivering essential nutrients and oxygen to the affected area to promote healing. Although this process is essential for recovery, excessive swelling under a cast can lead to discomfort, pain, and complications.

However, swelling can also occur if the cast is too tight. A snug cast can restrict blood flow, leading to elevated pressure in the damaged tissue — which in turn contributes to more swelling. It’s essential for your health that your cast fits correctly and supports your injured limb without causing undue pressure.

Here are a few reasons why edema might occur while wearing a cast:

Initial Trauma and Inflammation: When you first sustain an injury that requires a cast, the body's natural response is to send more blood and fluids to the affected area to promote healing. This process can result in initial swelling.

Impaired Circulation: A cast can restrict the normal flow of blood and fluids in the limb, leading to a buildup of these fluids. If the cast is too tight or improperly fit, it can exacerbate this problem by constricting blood vessels, which then makes the swelling worse.

Gravity: Sitting or standing for extended periods can encourage fluids to accumulate in the lower part of the casted limb, leading to swelling. This is why elevation is often recommended to counteract this effect.

Lack of Muscle Use: When a limb is immobilized in a cast, the normal contraction and relaxation of muscles, which help in circulating blood and lymphatic fluids, are reduced. This lack of activity can contribute to fluid retention and swelling.

Diet and Lifestyle Factors: Consuming a diet high in sodium can contribute to fluid retention. Also, dehydration can paradoxically cause the body to hold on to more fluid, adding to the swelling.

Secondary Infections or Complications: Though less common, an infection at the site of the injury or a complication like a blood clot could also lead to increased swelling.

Read More: Why Broken Bones Hurt and How to Alleviate the Discomfort

How to Reduce Swelling Under a Cast 

A person's leg is visible with a blue cast on the foot and ankle, extending above the calf, with crutches in the foreground.
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To help manage edema while wearing a cast, consider the following tips:

Elevate the Limb: Elevating your limb is one of the most effective ways to reduce swelling under a cast. When you sit or lie down, keep the injured area elevated above the level of your heart. This will help to reduce the pressure in the area, which can help reduce swelling. You can prop up your limb with pillows or a rolled-up towel. Try to keep it elevated as much as possible, even when sleeping.

Frequent Movement: If your healthcare provider permits, gently move your fingers or toes (if applicable) within the cast to stimulate blood circulation.

Ice: Applying ice wrapped in a cloth for short periods (around 15 minutes at a time) can help reduce swelling and discomfort. Make sure to avoid direct contact between ice and the skin to prevent frostbite.

Keep the Cast Dry: Moisture can contribute to skin irritation and further swelling. Follow your healthcare provider's instructions to keep the cast dry.

Keep Reading: How to Keep Your Cast Dry in the Shower

Stay Hydrated: Drinking enough water is important to help keep your body hydrated and reduce swelling under a cast. Swelling can occur from a buildup of fluid in the area, and staying hydrated can help to reduce this fluid buildup. Aim to drink at least 8 glasses of water a day, or more if you are exercising or in a hot environment.

Take Over-the-Counter Anti-Inflammatory Medications: If your physician allows, you can take over-the-counter medications, such as ibuprofen or acetaminophen, to help reduce inflammation and pain.

If the swelling is excessive, painful, or accompanied by changes in skin color, temperature, or sensation, contact your healthcare provider. Excessive swelling can sometimes lead to complications, so it's important to seek medical attention if you're concerned.

How Long Does Swelling Last?  

Swelling duration may vary depending on the severity of the injury, your overall health, and how well you manage it. Typically, swelling starts to decrease the first few days after injury and can continue to improve over the following weeks. In most cases, though, you should notice a significant reduction in swelling within the first week or two.

Will Swelling Under a Cast Go Away on Its Own?

The question of whether swelling under a cast will go away on its own is a nuanced one. While mild swelling may reduce over time as the body heals, it's crucial to take proactive steps to manage it effectively. Untreated, persistent swelling under a cast can lead to complications such as impaired blood flow, increased pain, and delayed healing.

In some cases, the cast itself might be the issue—perhaps it's too tight or not fitted correctly—which could exacerbate swelling. In such instances, immediate medical attention is required to adjust or replace the cast.

Keep Reading: 10 Signs A Broken Bone Is Healing

Identifying Abnormal Swelling Under a Cast

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Edward Olive - canva

Identifying abnormal swelling under a cast involves observing specific symptoms that deviate from what is generally considered normal. If you have any of these symptoms, you should contact a medical professional. These may include:

  • Persistent Pain: Mild discomfort is expected, but persistent or escalating pain could signify abnormal swelling.
  • Tingling Sensations: If you experience tingling that doesn’t go away, it could be a sign that the swelling is compressing nerves.
  • Numbness: Lack of sensation is often a critical sign that the swelling is excessive and needs immediate attention.
  • Capillary Refill: If you press on the fingernails or toenails of your affected limb (as applicable) and notice that the color does not return in two seconds or less, contact your doctor.
  • Color Changing: Blue or purple limbs or digits can be a sign of increased swelling to the point of dangerously reduced circulation. 

How Cast21 Can Help Reduce Swelling Under a Cast

If managing swelling under a cast is a concern for you, Cast21's breakthrough lattice design offers a game-changing solution. This innovative feature allows both doctors and patients to easily monitor swelling and for a cold compress to get closer to your body, thanks to its open structure that contours precisely to your wrist or arm. Not only does Cast21 provide the strong support you need during recovery, but its design also prioritizes your comfort.

A significant advantage of Cast21 is its revolutionary waterproof feature. Unlike traditional casts that can become breeding grounds for bacteria if exposed to moisture, Cast21 eliminates the need to worry about water-related complications, which could otherwise exacerbate swelling.

If you're seeking the right balance of comfort and support in a wrist cast, Cast21's advanced technology may offer you a more effective and comfortable healing journey, especially when it comes to managing swelling. Contact us today to discover how Cast21 can aid in your road to recovery.

Learn More: Everything You Need to Know About the Cast21 Alternative

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