What Happens if a Cast Gets Wet Inside?

A man with a blue waterproof cast cover on his forearm is shown in the shower, with water droplets visible, indicating the cast cover is protecting his cast while bathing.
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Every cast wearer's nightmare? The moment their cast becomes drenched.

One moment, you're confidently navigating life with a newly casted arm. But suddenly, disaster strikes—your cast is wet. Whether you accidentally dropped your arm in the sink, were caught by a beach wave, or were taken by surprise in a sudden rainstorm, you're left wondering: what happens when a cast gets wet on the inside?

When we think of orthopedic casts, it's often images of plaster-bound limbs decorated with messages from friends and the ever-looming task of maintaining its dryness. Thankfully, with innovative solutions like Cast21, the traditional concerns surrounding wet casts are being transformed.

In this blog post, we'll explore the potential consequences of a wet cast and what you can do to prevent them. We'll also provide information about the best waterproof casts on the market that allow you to shower and swim while being able to completely submerge your cast in water.

What is a cast?

An elderly person's arm is shown with a light blue fiberglass cast covering the forearm and wrist, fingers exposed, against a grey shirt.
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A cast is a hard, protective shell applied to a broken bone or injured area to promote healing by immobilizing it. 

There are two main types of casts - plaster and fiberglass. Plaster casts are cheaper and mold better to the body, but they're heavier and not water-resistant. Fiberglass casts, on the other hand, are lighter and more durable, and they can tolerate a bit of water. 

However, the padding underneath both types of casts is not water-friendly. While soft and comfortable, the padding underneath is a sponge for moisture. When it gets wet, it stays wet, creating a damp environment where bacteria thrive. This can lead to skin infections and even more serious conditions like gangrene.

When Water Meets Casts

Water and casts don't mix well. Even a small amount of moisture can have significant consequences. Let's explore why water is a cast's enemy.

What Happens if You Get a Plaster Cast Wet

Plaster casts are not waterproof, and they can start to fall apart when they get wet. Plaster casts are made of a mix of water and plaster of paris. When the plaster gets wet, it begins to dissolve and can loosen the fibers holding the cast together. This can cause the cast to change shape and eventually collapse. If the cast begins to disintegrate, it may disrupt the healing process and leave you vulnerable to re-injury. As a result, it is important to keep plaster casts dry at all times.

What Happens if You Get a Fiberglass Cast Wet 

While fiberglass casts are much more water-resistant than plaster casts, they are not completely waterproof and can become compromised if they get wet. The outer layer of the cast is waterproof, but the soft padding underneath is not. The moisture can cause the fibers to swell and loosen, leading to re-injury. In some cases, your doctor may be able to put a waterproof liner under the cast, which makes the entire cast waterproof. However, it is important to note that even with a waterproof liner, there is always a risk of water getting trapped and causing skin irritation. 

The Consequences of a Wet Cast

A healthcare provider's hand in a blue glove is adjusting a white plaster cast on a person's arm.
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So, what happens if a cast gets wet inside? The damp environment can lead to a host of problems:

Skin Maceration: Prolonged moisture from a wet cast can soften the skin beneath, leading to maceration. This oversaturated state makes the skin wrinkled and infection-prone. Skin infections caused by maceration can progress rapidly, so it's important to take measures to prevent them.

Fungal Infections: Wet casts can trap moisture, creating a perfect breeding ground for fungi. While many of these infections are generally mild, causing itchiness and irritation, some can escalate into severe conditions.

Material Degradation: Traditional plaster casts can lose their rigidity when wet. This can cause the cast to lose its shape, rendering it less effective at immobilizing the bone.

Odor and Discomfort: A wet cast can lead to unpleasant smells due to the growth of bacteria and fungi. Moreover, the dampness can cause itchiness, discomfort, and a heightened sense of confinement for the patient.

Re-fracture: In the worst-case scenario, a weakened cast could lead to the bone re-fracturing, setting you back in your recovery.

Mold and Mildew: Damp casts can breed mold and mildew, causing skin irritation and damaging the cast. If you detect mold or mildew, consult a medical professional about a potential cast replacement.

What to Do If Your Cast Gets Wet

Accidents happen. If your cast does get wet, don't panic. Here's what you can do to minimize damage:

Dry It Out: Use a hairdryer on the cool setting to dry out the cast. Never use heat, as it can burn the skin under the cast.

Check for Signs of Trouble: Keep an eye out for signs of skin irritation or infection. If you notice a foul smell, discharge, or persistent itching, seek medical attention immediately.

Consult a Healthcare Professional: If your cast is soaked through, it's best to consult a healthcare professional. They can assess the situation and decide if the cast needs to be replaced.

Preventing a Cast from Getting Wet 

A child's arm is covered by a transparent waterproof cast protector, which is sealed around the bicep, allowing the child to be in the water without getting the cast wet.
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Once you've experienced the challenge of a wet cast, you'll want to prevent it from happening again. Here are some practical tips to keep your cast dry:

Use a Cast Cover: Cast covers are waterproof protectors that can be slipped over the cast while bathing or participating in water activities. They create a tight seal at the edge, preventing water from seeping in.

Related Read: How to Use a Waterproof Cast Cover

Wrap It Up: If you don't have a cast cover, you can wrap your cast in a plastic bag and secure it with a rubber band. However, this isn't as reliable as a cast cover and should be a last resort.

Keep It Elevated: Keeping your cast elevated can help prevent accidental splashes from reaching it.

Be Mindful of the Weather: If it's raining or snowing, make sure to cover your cast before going outside.

Related Read: How to Keep Your Cast Dry in the Shower

Signs that Your Cast Needs to Be Replaced

Mold or Mildew Appearance: If you spot mold or mildew, it's a clear indication of moisture build-up, which can be detrimental to the skin beneath the cast.

Foul Odor: A bad smell emanating from the cast suggests bacterial growth or prolonged moisture exposure.

Redness or Swelling: These are warning signs of possible infections or complications. If unchecked, it could lead to more severe issues.

Drainage from the Cast: Any form of discharge from beneath the cast, be it pus or clear fluid, indicates potential infections or issues with the underlying wound.

Loose or Frayed Edges: If the cast edges become loose or start to fray, it may not be providing the necessary support.

Prolonged Itching or Discomfort: While some itching is normal, persistent discomfort might mean the cast is not fitting properly or there's a skin issue underneath.

Decreased Mobility: If you find it harder to move your fingers or toes (depending on the cast location), it could be a sign that the cast is too tight or not positioned correctly.

Frequently Asked Questions

A person is using a hairdryer to dry a blue fiberglass cast on their arm, suggesting an aftercare routine for the cast.
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Can I Waterproof My Cast?

Yes, you can waterproof your cast to a certain extent. While traditional plaster casts cannot be made entirely waterproof, they can be protected from water using waterproof cast covers or special plastic protectors designed to seal out moisture. If you anticipate frequent contact with water, you might consider discussing with your orthopedic doctor the possibility of getting a waterproof cast made of fiberglass and a special liner, which can be more resistant to water.

How Long Does it Take for a Wet Cast to Dry?

The drying time for a wet cast largely depends on the material of the cast and the extent of its wetness. A plaster cast can take anywhere from 24 to 72 hours to dry completely, depending on its thickness and environmental conditions. Fiberglass casts dry faster, usually within 20 minutes to 4 hours. However, if the padding inside either type of cast becomes wet, it may take longer, and there's a risk that it might not dry completely. Using a hairdryer on a cool setting or placing the cast in front of a fan can expedite the drying process.

Can I Swim with a Cast?

Swimming with a traditional plaster cast is not recommended as it can become soft and lose its shape when wet. However, if you have a waterproof cast made of fiberglass with a special liner, you might be able to swim. It's essential to consult with your orthopedic doctor before attempting to swim, and even with a waterproof cast, it's a good idea to use a waterproof cast cover as an extra layer of protection.

Related Read: How to swim with a cast 

What Happens If I Ignore a Wet Cast?

Ignoring a wet cast can lead to several complications. A wet cast can lose its rigidity and fail to support and stabilize the injured area, hindering proper healing. The damp environment inside a wet cast can also become a breeding ground for bacteria and fungi, leading to unpleasant odors, itching, skin irritation, and infections.

Can a Wet Cast Cause Infections?

Yes, a wet cast can potentially cause infections. When the padding inside a cast remains damp or wet for prolonged periods, it creates an ideal environment for bacteria and fungi to thrive. This can lead to skin infections, which might manifest as redness, swelling, warmth, and even discharge from the affected area. If you suspect an infection or notice any of these symptoms, consult with your healthcare provider right away.

The Cast21 Solution: A Waterproof Alternative

A young boy is smiling in a swimming pool, with a cast21 on his arm, showing a positive attitude while enjoying the water.

Cast21 is an orthopedic cast solution designed with the modern patient in mind. Unlike traditional plaster or fiberglass casts, Cast21 offers a waterproof alternative, allowing patients to shower, swim, or engage in other water-based activities without worry.

How Does Cast21 Work?

Material Advantages: Cast21 utilizes a resin-based lattice structure. This open design allows for ventilation, reducing potential skin complications and eliminating the usual discomforts associated with traditional casts.

Waterproof Nature: The very essence of Cast21's design is its impermeability to water. The material ensures that no moisture can seep into the cast, making it an ideal choice for those who lead an active lifestyle or simply wish to shower without a hitch.

Easy Application: The application of Cast21 is straightforward and quick, providing a snug fit that efficiently immobilizes the bone while offering superior comfort.

While traditional casts have served us well over the years, advancements in medical technology, such as Cast21, are paving the way for more patient-friendly solutions. No longer do individuals have to compromise their daily routines or live in constant fear of their cast getting wet.

With Cast21, not only is the risk of complications associated with a wet cast eliminated, but patients are also presented with a comfortable, breathable, and modern alternative.

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

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