What Is a Bone Growth Stimulator and How Does It Work?

A bone stimulator being used with Cast21 for a fracture
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Fractures, while common, can sometimes pose challenges in the healing process. When fractures don't heal naturally, innovative therapies like electrical stimulation, specifically bone growth stimulators, have emerged as potential solutions. But how exactly do they work? And who stands to benefit the most from their implementation? 

In this article, we'll delve into the world of bone stimulators, uncovering their mechanisms, benefits, types, and everything you need to know about integrating them into your fracture recovery journey.

How Bones Heal 

Fractures come in various forms, each requiring a delicate balance of factors for successful healing. Stability, proper blood supply, and adequate nutrition are essential components that contribute to the healing process. However, statistics reveal that approximately 5-10% of fractures face challenges in healing properly.¹ Factors, like compromised blood flow or severe injuries, can impede the body's natural healing mechanisms, leading to nonunions or delayed healing.

Read More: How to Tell the Difference Between a Malunion and Nonunion Fracture

What are Bone Stimulators? 

Physiotherapist treating patient with electrical stimulation
Marizza - canva.com

A bone stimulator is a medical device used to promote bone healing and regeneration. It is often employed in cases of fractures that are slow to heal, non-union fractures (where the broken bone fails to heal), or cases of spinal fusion surgery. 

Bone stimulators work by applying specific types of energy, such as electrical currents, ultrasound waves, or electromagnetic fields, to the site of the fracture or surgical procedure. These energies are believed to enhance the natural bone healing process by stimulating cellular activity, blood flow, and the deposition of new bone tissue.

There are two main categories of bone stimulators:

Electrical Bone Stimulators: These devices use mild electric currents to help heal fractured or mending bones. They come in two types: invasive and non-invasive. Invasive electrical bone stimulators need a surgical procedure to place electrodes close to the fracture site. On the other hand, non-invasive devices can be worn external to the body, often as part of a brace or wrap, and are placed on the skin over the fractured area.

Ultrasound Bone Stimulators: These devices use high-frequency sound waves to stimulate bone healing. Like non-invasive electrical stimulators, ultrasound bone stimulators are also applied externally. The ultrasound waves are directed towards the bone, and the energy is thought to promote the migration of cells involved in bone healing and stimulate tissue regeneration.

Who Can Benefit from Bone Stimulators?

Close up image of a forearm fiberglass cast
Sajee_Rd - canva.com

Patients who exhibit the following conditions could potentially benefit from the use of bone stimulators:

Fractures Slow to Heal: Bone stimulators can be beneficial for fractures that take longer than usual to heal. They deliver energy to the fracture site, stimulating cellular activity, blood flow, and new bone growth, thereby expediting the healing process.

Nonunion Fractures: Individuals with nonunion fractures, where bones fail to heal properly, may find bone stimulators helpful. These devices aim to create an environment conducive to bone growth, improving the chances of successful healing.

Spinal Fusion Surgery: Bone stimulators can assist in cases of spinal fusion surgery. By delivering energy to the surgical site, they promote bone growth and fusion, enhancing the success of the procedure.

Certain Medical Conditions: Individuals with conditions like diabetes or who smoke, which can impede normal healing, may benefit from bone stimulators. These devices help counteract factors that hinder the healing process.

Uncomplicated Fractures: While bone stimulators are mainly used for challenging cases like nonunion fractures, their effectiveness for uncomplicated fractures is still debated.

Read More: 7 Reasons a Broken Bone Is Not Healing

Are Bone Stimulators Safe?

FDA-approved at-home bone growth stimulators are considered safe when used as prescribed by a medical professional. However, as with any medical treatment, there are potential risks. Rarely, skin irritation or discomfort may occur where the stimulator is applied. 

Who Should Not Use a Bone Stimulator? 

Certain individuals should avoid using bone stimulators without consulting a healthcare professional due to potential risks. These include:

Pregnant Women: Pregnant women are advised not to use bone stimulators as the effects on the fetus are not fully understood.

Individuals with Growth Disorders: Individuals with skeletal immaturity or growth disorders should avoid bone stimulators, as their bones are not fully developed.

Bone Stabilization with Magnetic Materials: Individuals with bone stabilization using magnetic materials should avoid using bone stimulators due to potential interactions that could affect the stability of the magnetic materials. 

Fractures with Excessive Gap: Fractures with a gap exceeding 50% of the bone's diameter may not be suitable for bone stimulator use.

Presence of Pseudarthrosis: The presence of a "false joint" or pseudarthrosis might contraindicate the use of bone stimulators.

Implanted Pacemakers or Defibrillators: Individuals with pacemakers or defibrillators should consult their cardiologist before using bone stimulators due to potential electromagnetic interference.

Skull Fractures: The complex structure and sensitive nature of the skull, as well as potential interference with neurological functions, make the use of bone stimulators in this region inappropriate and potentially harmful.²

As always, medical advice should be sought from a qualified healthcare professional to determine the appropriateness of using a bone stimulator based on an individual's unique medical situation.

How long should you use a bone growth stimulator?

Typically, bone growth stimulators are prescribed for a specific period of time, which can range from a few weeks to several months. The specific duration will depend on factors such as the type of fracture or bone condition, the location of the injury, the individual's overall health, and how well the bone is responding to the treatment.

The Cast Alternative That Can Be Used with a Bone Stimulator

A bone stimulator being used with Cast21 for a fracture

When it comes to healing fractures and injuries, innovation knows no bounds. The Cast21 Orthopedic Cast Alternative stands at the forefront of this progress, offering a transformative approach to recovery that seamlessly integrates with bone stimulators.

Cast21 has reimagined the way we heal from fractures by introducing an innovative open lattice design. Unlike traditional casts, Cast21's alternative is lightweight, breathable, and even waterproof. What's even more intriguing is that this orthopedic cast alternative is compatible with bone stimulators, allowing for a combined approach to healing.

Whether you're recovering from a fracture, seeking improved comfort, or looking for an effective way to incorporate a bone stimulator into your healing journey, the Cast21 Orthopedic Cast Alternative could be the answer you've been waiting for. Contact Cast21 today to locate a provider near you.

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


  1. Victoria, G., Petrisor, B., Drew, B., & Dick, D. (2009). Bone stimulation for fracture healing: What's all the fuss? Indian Journal of Orthopaedics, 43(2), 117-120. https://doi.org/10.4103/0019-5413.50844
  2. Center for Devices and Radiological Health. (n.d.). AccelStim bone growth stimulator – p210035. U.S. Food and Drug Administration. https://www.fda.gov/medical-devices/recently-approved-devices/accelstim-bone-growth-stimulator-p210035  
  3. WebMD. (n.d.). Bone stimulators: Are they effective?. WebMD. https://www.webmd.com/a-to-z-guides/what-to-know-about-bone-stimulators-for-fracture 

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