The Truth About Fiberglass Casts for Bone Fractures (2023)

When you break a bone, your doctor will likely recommend that you have a cast put on to help stabilize the injury so that it can heal properly. You may have heard that fiberglass casts are a good option, but is that really true?

This blog post will give you all the information you need about fiberglass casts, from how they are applied to how long you’ll have to wear them. We’ll also explore the pros and cons of fiberglass casts and provide tips on taking care of your cast while your fracture heals. If you’re considering a fiberglass cast, this guide is a must-read before making your decision.

What is a Fiberglass Cast?

A fiberglass cast is a type of medical dressing made of synthetic materials used to support and protect bones that have been broken or joints that need stabilization.

A typical fiberglass cast is made of three layers. The inner layer is a stockinette, which is a knitted fabric. The middle layer is a cotton bandage that is wrapped around the limb. The outer-mostlayer is a resin and fiberglass composite that is activated and then wrapped around the other layers. The purpose of the three layers is to provide support and protection for broken bones and skin.

The fiberglass outer layer is hard and strong, and it helps to keep the inner layers in place. The cotton bandage helps to absorb any sweat or moisture that may build up under the cast, and the stockinette helps to prevent the skin from rubbing against the rough edges of the fiberglass. The two inner layers can also protect you from any cast saw accidents.

Fascinating History of Fiberglass Casts

The medical practice of immobilizing broken bones with casts and splints has been around for centuries, with the earliest known examples dating back to ancient Egypt. The first plaster casts were made from a mixture of plaster of paris and water. This was the standard treatment of broken bones for many years. In the 1970s, a team of doctors sought a material that would be lighter and more comfortable than a plaster cast. After trying a variety of other synthetic materials, fiberglass casting tape was developed, and it quickly became popular with patients seeking treatment for their injured arm or leg.

How are Fiberglass Casts Applied?

The Truth About Fiberglass Casts for Bone Fractures (1)

The application process of a fiberglass cast is relatively straightforward, but it must be done quickly to avoid the material hardening before it is in the desired shape.

First, a medical professional may clean your skin with soap and water to prepare for the cast application. Next, they will apply a stockinette to your injured limb. After that, they will apply a soft cotton padding for cushioning. Finally, they will apply several layers of resinous fiberglass casting material.

The material will harden quickly, so the clinician will need to work quickly to mold the cast to the desired shape. Once the cast is in place, you should not remove it yourself. You'll need to see a doctor or cast technician to have it removed. The entire process can take about 30 minutes depending on what is being casted.

Fiberglass Cast Drying Time

Once a fiberglass cast has been applied, it can take some time for the cast material to dry. The number of fiberglass layers and the air's humidity can affect the drying time, but typically it takes 1-2 hours for the cast to fully harden. During this time, it's important to avoid moving or putting weight on the cast, as this could disrupt the drying process and cause the cast to misshapen. Once the cast is dry, it will provide support and protection for the injured area while it heals.

How Long Does a Fiberglass Cast Stay On?

Patients can wear most fiberglass casts for up to six weeks, but this will vary depending on the nature of the injury. In some cases, a fiberglass cast may need to be removed sooner if it begins to cause irritation or discomfort to the affected limb. If you need to be immobilized for longer, you may need to have your cast replaced.

How is a Fiberglass Cast Removed?

The Truth About Fiberglass Casts for Bone Fractures (2)

Once the bone has mended, the fiberglass cast needs to be removed from the body by a medical professional. The most commonly used tool for cast removal is a cast saw. This type of saw uses a very thin, vibrating blade that can quickly cut through the materials making up the cast. However, because the blade is so thin, sharp, and fast moving, it is also important to be very careful when using a cast saw. Additionally, technicians may use cast spreaders or ultra-strong scissors. These tools can also be effective in cutting through the materials making up the cast. Usually, the entire process takes between 15 and 20 minutes and can depend on the size of your cast.

Fiberglass Cast Care

When you have a cast put on, it is important to follow the doctor's instructions for care. Here are some cast care tips:

  • Try to keep the cast clean and dry. The fiberglass part of the cast is designed to repel water, but if the padding underneath gets wet, it can lead to skin irritation or even infection. If you get your cast wet, use a hair dryer on the cool setting to dry any wet areas.
  • Never shove objects inside the cast. It may be tempting to reach in with something to scratch an itch, but doing so can damage the skin, may lead to infection, and can disrupt the healing process.
  • Do not put any lotions, oils, or powders on the skin under the cast without first consulting your doctor. This can cause skin irritation.
  • Avoid activities that could impact or put pressure on the area with the cast. This could potentially damage the cast or cause further injury.

If you have an itchy cast or you notice your cast has a foul odor, learn more about how to deal with these common problems.

Can you Get a Fiberglass Cast Wet?

The Truth About Fiberglass Casts for Bone Fractures (3)

When you have a fiberglass cast, it's important to avoid getting it wet. If the cast gets completely submerged in water, it can cause the fiberglass to unravel and the cotton bandage to swell. This damages the materials and weakens the cast.

Although, many fiberglass casts can be made waterproof by using waterproof padding material under the hard cast shell. Rather than using traditional cotton padding, waterproof casts use a special padding material that is impervious to water.

If your fiberglass cast is not waterproof, be sure to cover your cast with a waterproof sleeve or bag when taking a shower or bath. Patients can use special covers to protect the cast from getting wet. Learn more about how to keep your cast dry in the shower.

If you have a wet cast, you should dry it off as soon as possible. You can use a hair dryer on a cool setting to help dry the inside of the cast. If the cast is wet on the inside, you should call your doctor for medical advice.

Fiberglass Cast Advantages and Disadvantages

The Truth About Fiberglass Casts for Bone Fractures (4)

When it comes to broken bones, the type of cast you receive can make a big difference in your recovery experience. Let’s take a look at the advantages and disadvantages fiberglass casts offer.


Fiberglass is lighter and more porous than plaster, allowing airflow and reducing the risk of itchy skin This makes it more comfortable for patients to wear for extended periods of time. Fiberglass arm casts can also be stronger than plaster casts, making them less likely to break if they are bumped or experience any other type of impact. However, fiberglass can be more expensive than plaster, and it can also cause skin irritation in some people. Overall, though, fiberglass is a versatile and durable material that can be an excellent choice for a cast.


Despite its advantages, fiberglass isn't without its drawbacks. One of the most common disadvantages of fiberglass casting is that it sets very quickly. This can be a problem for less experienced medical providers who may not have enough time to properly wrap the injured extremity before the cast sets. In addition, fiberglass casts have a bad reputation for being smelly and uncomfortable.

Another disadvantage to consider is that a special cast saw is required to remove the cast once the injury has healed. While this may not be a big inconvenience for some, for others it can be quite scary. Additionally, using a cast saw can be dangerous. If not used properly, the saw can cause further injury to the patient by burning or cutting the skin. For this reason, it is important to make sure that the medical provider removing the cast is properly trained and knows how to use the cast saw correctly.

When to See a Doctor

Even with the best care, there are times when you may need to see a doctor for your cast. If the skin underneath the cast becomes unbearably itchy, or if you notice a bad smell coming from the cast, these could be signs of an infection. In either case, seeking medical attention is essential in order to ensure that your injury heals properly.

Is there an Alternative to a Fiberglass Cast?

Traditional fiberglass casts can be cumbersome and uncomfortable, making it difficult to go about your normal daily activities. Fortunately, there is a new product on the market that offers all the healing benefits of a traditional cast, without any discomfort.

Cast21 is a new type of medical casting alternative that has been developed for the 21st-century lifestyle, boasting many advantages over traditional casting methods. Unlike traditional casting, Cast21 doesn't require any messy plaster or fiberglass bandages. Instead, the injured limb is simply placed into an open lattice sleeve which is then filled with a fast-curing proprietary formula. The result is a strong, yet seemingly weightless cast alternative that is comfortable to wear.

Because the Cast21 system is completely waterproof, it can be worn while bathing or swimming. Overall, Cast21 provides a more convenient alternative to traditional casting methods. Plus, they're available in a variety of colors to suit your style.

If you or someone you know has suffered a broken bone, be sure to ask your doctor about Cast21 or contact our team of professionals with any questions you may have.

Medical Disclaimer

Cast21's articles and content are for informational and educational purposes only. Our website is not intended to be a substitute for professional medical advice, diagnosis, or treatment.


What is the disadvantage of fiberglass cast? ›

One of the most common disadvantages of fiberglass casting is that it sets very quickly. This can be a problem for less experienced medical providers who may not have enough time to properly wrap the injured extremity before the cast sets.

Why don t doctors use casts anymore? ›

But casts–and other treatments for arm and leg injuries– have changed over the years. For many fractures, casts still play a crucial role in the healing process. But for other injuries, orthopaedists are now opting for removable modern splints and boots that offer greater comfort and flexibility.

Are fiberglass casts still used? ›

Today, synthetic casts are used more often than plaster casts. They're usually made out of a material called fiberglass, a type of moldable plastic. Fiberglass casts are applied in a similar manner to plaster casts. A stockinette is placed on the injured area, then wrapped in soft cotton padding.

Can you XRAY through a fibreglass cast? ›

Fiberglass casts.

These plastic casts are typically lighter and more durable than plaster casts. Also, X-rays penetrate fiberglass casts better than plaster casts — making it easier for your doctor to examine your child's bones while he or she is still wearing the cast.

Can fibreglass cause health problems? ›

No long-term health effects should occur from touching fiberglass. Eyes may become red and irritated after exposure to fiberglass. Soreness in the nose and throat can result when fibers are inhaled. Asthma and bronchitis can be aggravated by exposure to fiberglass.

What is an advantage to using a fiberglass cast instead of a plaster cast? ›

Fiberglass has several advantages compared to plaster. It weighs less, so the cast made from it will be lighter. More durable and porous, fiberglass allows air to flow in and out. Fiberglass is the better choice in case the limb must be X-rayed during the healing process.

Can a bone heal without a cast? ›

Technically speaking, the answer to the question “can broken bones heal without a cast?” is yes. Assuming conditions are just right, a broken bone can heal without a cast. However, (and very importantly) it doesn't work in all cases. Likewise, a broken bone left to heal without a cast may heal improperly.

Is there a modern cast for broken bones? ›

– A futuristic innovation is changing the way doctors set broken bones. A startup company called Cast21 has created a new type of cast that completely overhauls its plaster and fiberglass predecessors. It takes just minutes to put on and lets patients enjoy an active life, even allowing them to swim and shower with it.

Is a fracture worse than a break? ›

Some people assume that fractured bones are more serious than broken bones, while others assume it's the other way around. But the truth is that these terms are used interchangeably, and they have the same meaning to medical professionals.

What happens when fiberglass cast gets wet? ›

Moisture can collect under the cast and cause skin irritation and itching. It can make infection more likely if you have had surgery or have a wound under the cast. If you have a water-resistant cast, ask your doctor how often it can get wet and how to take care of it.

How do they remove a fiberglass cast? ›

Once it's time for cast removal, a healthcare provider uses a cast saw to cut through the plaster or fiberglass the cast is made of. It may seem scary to have this tool so close to your skin, but cast removal is safe when done by a qualified healthcare provider.

Can you ice through a fiberglass cast? ›

Ice your cast for the first 48 hours

Yes, the ice will penetrate through your cast if you leave it on long enough. This will help reduce any swelling and pain. One of the best methods to ice down your cast is to use bags of frozen vegetables.

Can you fly with a fiberglass cast? ›

If you have an upper body cast or your leg is in a plaster cast below your knee and you can bend your knee, you'll be able to sit in a normal seat. If your plaster cast covers your knee, you won't be able to bend it, so you'll need to make special seating arrangements with your airline.

How long does it take for a fiberglass cast to set? ›

Fiberglass dries in 15 to 30 minutes, but plaster can take longer. If you are walking on the cast or splint, the drying time will be longer. On average, plaster will take about a day and a half before it's hard enough to support your weight, but fiberglass will take about 20 to 30 minutes.

How long does a fiberglass cast take to harden? ›

It takes up to 48 hours for a plaster cast to dry. Fiberglass casts can take up to two hours. While your cast is drying, keep it uncovered as much as possible to help it to dry faster. While it is drying, do not do anything to change the shape of or alter your cast in any way.

Should I worry about fiberglass? ›

The fiberglass can give you tiny cuts on your skin, which can cause rashes and blisters, and irritate your eyes and lungs. If this material is inhaled, it can also be dangerous and worsen asthma. Studies have shown the inhalation of airborne fiberglass can lead to adverse health effects.

Does fibreglass have asbestos in it? ›

You will not find asbestos in any batt-form of fibreglass insulation. This wool-type material is a glass fibre product, so it doesn't normally contain asbestos. This is an artificial, man-made product whereas asbestos is a natural product found in rocks.

Does fibreglass cause COPD? ›

Although presence of any allergies had a significant (p = 0.01) influence on the association between fiberglass exposure and COPD, i.e., a higher association between fiberglass and COPD among the nonallergic individuals (PR: 1.93; 95%CI: 0.74, 5.03) than those who were allergic (PR: 0.48; 9%%CI: 0.27, 0.87) (Table S10) ...

When can you bear weight on a fiberglass cast? ›

Synthetic casts

If you have a synthetic (fiberglass) cast applied, you may put weight on your newly casted leg 30 minutes after it is applied, unless you are told otherwise by your physician.

Is fiberglass cast comfortable? ›

Fiberglass casts are more porous than plaster casts. This allows the doctor to take X-rays of the injury without removing the cast. Since they are porous, they are also more breathable, thereby making them more comfortable to wear. They make the skin less prone to irritation.

How do I speed up the healing of a broken bone naturally? ›

A healthy diet is one full of vegetables, fruits, lean protein and water. In particular, calcium, vitamin D and protein will be important during the bone healing process, so be sure you're focusing on food sources rich in these nutrients, including dark, leafy greens, broccoli, fish, meat, yogurt, nuts and seeds.

What is the fastest a broken bone can heal? ›

Most fractures heal in 6-8 weeks, but this varies tremendously from bone to bone and in each person based on many of the factors discussed above. Hand and wrist fractures often heal in 4-6 weeks whereas a tibia fracture may take 20 weeks or more.

Is walking good for broken bones? ›

But somewhat counter-intuitively, exercise may actually play an important role in making sure fractures heal properly. In fact, research shows that being physically active can promote bone healing – and even help you avoid future fractures. Almost 178 million new bone fractures happen worldwide each year.

How much does fiberglass cast cost? ›

Normally, Fiberglass Casting & POP Bandage price in India ranges between INR Rs. 300 to INR Rs. 3k.

Is plaster of Paris still used for broken bones? ›

Plaster can be used not only for treatment of fractured bones but also supports sprained ligaments, and inflamed and infected soft tissues. It usually sets in few minutes, but needs between 36-72 hours to completely dry. Leg plasters are able to bear weight after 48 hours.

Is splint better than cast? ›

That's because casts are typically made from stronger materials than splints, making them more durable and less likely to break or come loose. Plus, because they completely encase the injured area, casts also provide better protection from further injury.

What is the most painful type of bone fracture? ›

Comminuted fracture

This type of fracture requires a lot of force, which causes your bone to break into several pieces. A comminuted fracture typically brings very intense pain. Because the fracture is in several pieces, surgery is usually required to fix it.

Which bone fracture is the most painful? ›

The Femur is often put at the top of the most painful bones to break. Your Femur is the longest and strongest bone in your body, running from your hip to your knee. Given its importance, it's not surprising that breaking this bone is an incredibly painful experience, especially with the constant weight being put on it.

When does a fracture stop hurting? ›

After about a week or two, the worst of the pain will be over. What happens next is that the fractured bone and the soft tissue around it start to heal. This takes a couple of weeks and is called subacute pain. You may still be on pain medication, but it may be a lower dosage or a weaker drug.

How strong is a fiberglass cast? ›

A fiberglass cast weighs only a few ounces and several layers of the fiberglass can be used to create a walking cast that is strong enough to support a person's weight within about 20 minutes of its application. As an example, a fiberglass short leg cast, sometimes called a boot cast, weighs about a pound.

Is it normal to have pain while in a cast? ›

Because bones, torn ligaments, tendons, and other tissues can take weeks or months to heal, you may be stuck with your cast for a while. Although the pain may ease after a few weeks, the discomfort - swelling, itchiness, or soreness - may last the entire time.

Why does my cast feel tight? ›

Proper Cast Fit

Your cast should feel very snug, maybe even tight, for the first few days after your injury. This is normal. A cast is meant to help your injury heal by protecting it from movement. Feeling a reasonable amount of tightness means the cast is doing its' job!

When can you walk after fiberglass cast? ›

They will help keep the pressure off of your injured limb while it is healing. If you have a walking cast, do not walk on it until it is completely dry and hard (about 1 hour for a fiberglass cast and 2-3 days for a plaster cast).

Does fracture hurt after removing cast? ›

After the cast is removed, it is normal for there to be some discomfort in the bones and joints that were immobilized, for the arm or leg to be smaller than the other side, and for the skin to have some changes (dry skin and more hair). A few baths in warm water will soak off the dry, flaky skin.

Can a leg cast cause a blood clot? ›

If you wear a plaster cast or brace for several days or weeks, the blood flow through your veins is slower than if you can move normally. This increases the risk of a blood clot (thrombus) forming in a leg or pelvic vein. Blood clots may end up blocking veins, preventing blood from flowing through them properly.

Is it OK to drive with a cast on? ›

As a rule, driving with a lower limb cast is completely forbidden as use of the pedals is inadequate. Driving with an upper limb cast is generally not advised. If the cast is worn on the side of the limb used for changing gears or using the handbrake, then it makes driving more difficult.

Does flying with a broken bone hurt? ›

Flying with a fracture is safe as long as it is minor and stable, and the plaster cast is put on at least 48 hours before the flight. If not, the cast will almost certainly be split in half to avoid complications like deep vein thrombosis or compartment syndrome.

Can you be allergic to a fiberglass cast? ›

In the recent years, common use of synthetic cast (45% polyurethane resin and 55% fiberglass) and also undercast cotton padding (synthetic fiber) caused an increased incidence of allergic contact dermatitis.

What are three reasons you may contact your doctor regarding your cast? ›

Call your doctor if:
  • The cast feels too tight.
  • The cast was comfortable but is now uncomfortable.
  • You have new pain or pain that gets worse.
  • Your fingers or toes get more swollen, change colors, hurt, or feel numb.
  • Something is stuck in the cast, like a piece of food.

How many layers of fiberglass do you need for a cast? ›

Use 4 to 6 layers of plaster (typically) or 2 to 4 layers of fiberglass to ensure adequate strength of the cast.

What are the advantages of fiberglass cast? ›

Fiberglass has several advantages compared to plaster. It weighs less, so the cast made from it will be lighter. More durable and porous, fiberglass allows air to flow in and out. Fiberglass is the better choice in case the limb must be X-rayed during the healing process.

Do casts get looser over time? ›

The initial cast may need to be replaced during the treatment period, as it's common for a common for the case to become loose as the initial swelling begins to come down.

Can you shower with a fiberglass cast? ›

The fibreglass part of your cast can get wet. But getting the inside wet can cause problems. Plaster casts should be kept dry. Use a bag or tape a sheet of plastic to cover your cast when you take a shower or bath or when you have any other contact with water.

What are the limitations of Fibreglass? ›

Fibreglass is a popular roofing material, but it has several disadvantages. It can be expensive, difficult to install, and it can be damaged by hail. Fibreglass roofs are also not as energy-efficient as other roofing materials and they can discolor over time.

Can you sweat in a fiberglass cast? ›

Be diligent about hygiene after sweating.

Sweat beneath your cast is likely, especially if you are participating in physical therapy or other form of exercise. Check with your doctor about using a moisture absorbing powder, such as Gold Bond, around your cast.

What is the primary disadvantage of glass fiber? ›

Disadvantage of glass fibers are warpage, low weld, and knit line strength, higher viscosity of melt, and low surface quality and increase in damage to machine and tool due to abrasion.

Can I drive with a Fibreglass cast? ›

"Basically the rules state that you can't drive with any kind of arm cast on because you'll lose control of the wheel."

Does fiberglass break easily? ›

Fiberglass is a very strong and durable material that will last for many years. They can withstand extreme weather conditions without cracking, chipping, or breaking.

Which one of these is a disadvantage of fiberglass insulation? ›

Moisture Issues

Fiberglass insulation is particularly vulnerable to moisture. Unlike alternatives such as foam board or sprayed foam insulation, wet fiberglass insulation loses all R-value and has almost no insulating properties until it dries out.

Do fiberglass casts smell? ›

Unfortunately, a cast can start to stink, and often the smell can become quite bad. Once a cast starts to smell bad, it is unlikely that it will start to smell good. Cast odor tends to be most problematic in young children and athletes.

What are the pros and cons of Fibreglass? ›

Fibreglass last a long time, it can be coloured, shiny or dull. It is low maintenance, anti-magnetic, fire resistant, good electrical insulator and weatherproof. The disadvantages is that it needs to be re-gel coated about every five years and can result in airborne fibres which may be an issue to asthma sufferers.

What are the pros of fiberglass? ›


The special evaluations of fiberglass give it many unique and unique properties: high resistance to bending, tensile, compressive, non-flammable, high temperature and humidity resistance, resistance to chemical and biological effects, relatively low density.

What is the difference between fiberglass and glass fiber? ›

Fiberglass is a type of fiber-reinforced plastic where glass fiber is the reinforced plastic. That is why fiberglass is sometimes known as glass fiber reinforced plastic or glass reinforced plastic. Glass fibers can be comprised of different types of glass.

Top Articles
Latest Posts
Article information

Author: Corie Satterfield

Last Updated: 08/10/2023

Views: 5578

Rating: 4.1 / 5 (42 voted)

Reviews: 81% of readers found this page helpful

Author information

Name: Corie Satterfield

Birthday: 1992-08-19

Address: 850 Benjamin Bridge, Dickinsonchester, CO 68572-0542

Phone: +26813599986666

Job: Sales Manager

Hobby: Table tennis, Soapmaking, Flower arranging, amateur radio, Rock climbing, scrapbook, Horseback riding

Introduction: My name is Corie Satterfield, I am a fancy, perfect, spotless, quaint, fantastic, funny, lucky person who loves writing and wants to share my knowledge and understanding with you.