Orthopedic implants replace or support a damaged or diseased joint, bone, or cartilage. They have completely revolutionized the orthopedic field by restoring mobility to patients suffering from musculoskeletal problems and injuries. These implants join with healthy bone and tissue to ensure stability and quicker recovery. Orthopedic prosthetic implantation presents several risks. That is why these implants are made with biocompatible metals, polymers, and ceramics. However, while careful material selection is essential, surface treatment is equally important. These surface treatments help in ensuring long-term reliability, integrity, and longevity.
This article discusses the role of surface treatments along with how they help improve orthopedic implants. Specifically, we focus on surface coatings for prosthetic devices. We will touch on a wide range of surface modifications and also highlight hydrophilic orthopedic implant coatings. That is because these are the most popular and effective option for these devices. So if you are a biomedical engineer you will want to read to the end to learn how you can leverage these coatings to meet your implant product requirements.
Related: Hydrophilic Implant Coatings: Comprehensive Guide for a wide range of implants.
Surface Treatments and Their Role in Orthopedic Implants
There are many success factors for ortho implants inside the body. One of the biggest is their ability to adhere and seamlessly integrate with biological tissues without causing adverse reactions. Studies show that nearly 10% of joint replacements may require revision surgery within the first ten years. This is due to implant wear, corrosion, or infection.
Surface treatment is a process of modifying a device’s natural surface properties. This modification improves the implant’s adhesion, durability, biocompatibility, and more.
Orthopedic implants are made from many materials. These include metals like titanium and stainless steel, polymers such as polyethylene and PEEK, and bioceramics like hydroxyapatite. Their performance within the biological environment can be improved with surface modification. As such, it is common to coat implants with surface treatments, such as hydrophilic, orthopedic implant coatings. These treatments ensure smooth insertion. They also improve osseointegration, enhance integrity and adhesion, reduce the risk of infections, and more.
So how can you treat and modify the devices? We dive into this below in more detail.
Types of Surface Modification Techniques
Medical device manufacturers are continuously looking for ways to improve the performance and safety of their devices. Surface modifications are a tried and tested way to help in this area. Each treatment is intended to change the properties and the functionality of the device’s surface.
Here are the most common surface modification techniques that have been used over the past few decades:
- Coating-Based Techniques: This is where medical coatings are applied to the surface of the device. The main purpose of surface coatings is to ensure that the medical device meets strict performance, safety, and regulatory requirements. There are different types of medical coatings available in the market. For example, hydrophilic, hydrophobic, and antimicrobial coatings. Hydrophilic medical coatings are the most common.
- Physical Surface Modification Techniques: These include laser-blasting, sandblasting, and plasma treatment. They are all based on the use of mechanical or thermal methods to modify the surface properties.
- Chemical Techniques: With this technique the medical device surface is modified using chemical agents. Etching is the most common example of chemical surface treatment techniques. For example, it is beneficial in the case of metal implants that are made up of titanium and stainless steel.
Coating-based surface modification techniques are more versatile and can be used to enhance multiple properties. As a result, we will focus on Orthopedic Implant Coatings in detail in the following sections.
Types of Surface Coatings Applied to Orthopedic Implants
There is a wide range of medical coatings used on implants. As mentioned above, the coatings modify the implant’s surface, changing its properties and functionalities. These coatings ultimately improve the implant, which helps patients regain mobility and alleviate pain. The right choice of coating depends upon the anatomical location and extent of the damage.
5 most common types of ortho implant coatings
- Metallic Coatings: This type of ortho implant coating helps improve strength, surface hardness, and finishing. They are commonly known as wear-resistant coatings. Titanium nitride (TiN) and zirconium nitride (ZrN) are the two most popular metallic coatings applied to orthopedic implants.
- Hydroxyapatite (HA) Coatings: Hydroxyapatite is a calcium phosphate-based ceramic that promotes tissue integration and bone growth. The porous hydroxyapatite (HA) significantly increases the durability and biocompatibility of joint replacement prostheses (JRP).
- Antimicrobial Coatings: As per the reports, healthcare-associated infections (HAIs) are one of the leading causes of increased healthcare costs and extended hospital stays. Early post-operative infections can be catastrophic. That’s why antimicrobial coatings are a must for orthopedic implants. They prevent the growth of microorganisms such as fungi and bacteria. It should be noted that hydrophilic coatings can be formulated to have antimicrobial properties. Learn more details about hydrophilic antimicrobial coatings.
- Porous Coatings: These coatings are mainly applied to titanium and CoCr orthopedics implants. They drastically improve the osteointegration and longevity of the implant. A variety of porous metallic materials, including stainless steel, titanium, or tantalum are used to design reliable and efficient coatings. Bone tissues grows onto and infiltrates the voids of the porous structure for better integration.
- Polymer Coatings: There are a variety of biocompatible and biodegradable polymer-based coatings that can be applied to orthopedic implants. They can significantly improve tissue integration and reduce the risk of implant failure.
- Hydrophilic coatings have gained widespread use with many medical devices, implants, and surgical instruments that are inserted into the human body. In fact, they hold approximately 45% of the total market revenue.
Based on their benefits and widespread use, we will cover hydrophilic coatings in more detail below.
What are Hydrophilic Coatings?
The term “hydro” means water, and “philic” means affinity or love for. As such, hydrophilic coatings are surface treatments that attract and hold water or liquid molecules to the medical device’s surface. In other words, they make the device’s surface hydrophilic, or water-loving.
They are activated in the presence of biological fluids. A thin, highly lubricious layer is formed on the surface of medical devices once they are activated. As such, they are referred to as “slippery-when-wet” coatings.
Their primary purpose is to reduce friction, ensuring smooth and safe insertion of medical devices during operational procedures. However, nowadays they are more than just friction reduction coatings. Working with suppliers like Hydromer, Inc., they can be custom-formulated to provide advanced functionalities. These include corrosion resistance, thromboresistance, antimicrobial properties that help reduce infections, and more. The application of these coatings has brought enormous improvements to orthopedic care.
Below we discuss the benefits of Hydrophilic Orthopedic Implant Coatings.
Benefits of Hydromer® Hydrophilic Coatings and Hydrogels in Orthopedic Implants
As we mentioned above, hydrophilic implant coatings can be custom-formulated to enhance multiple characteristics of orthopedic implants. In addition, they can serve multiple functionalities.
Top 6 reasons why you should apply hydrophilic coatings to ortho implants:
Reduced Friction
Hydrophilic coatings are “slippery-when-wet” surface modifications. They significantly improve the lubricity, which is a crucial property for medical devices that are inserted into the body. Surgeons can easily insert and place the orthopedic implants at the target location when they have hydrophilic coatings.
Improved Biocompatibility
Orthopedic implants must function as intended without harming surrounding tissues or bones. They must be biofunctional. This ensures they seamlessly integrate with the body’s natural tissues and ensure effective and safe operation. Hydrophilic coatings are non-toxic and non-carcinogenic. They help orthopedic implants function safely and effectively within the biological environment.
Reduced Risk of Infections
Implant-associated infections are one of the major complications in orthopedic and other implantations. They can occur any time during or after surgery. That’s why proper care is essential. Companies like Hydromer® manufacture chitosan-based hydrophilic coatings that can inhibit microbial growth.
Enhanced Osseointegration
Osseointegration is where an implant fuses with the human bone. Bone integration is critical for long-term success and stability of orthopedic implants. The wettability and water-attracting properties of hydrophilic coatings promote tissue integration. Their main purpose is to create a biocompatible surface capable of fusing with the surrounding bone and tissues.
Drug-Eluting Capabilities
Hydrophilic coatings can release a therapeutic drug dose over a desired period. Such customized coatings are applied to orthopedic implants to ensure localized and more efficient drug delivery.
Corrosion Resistance
Most of the orthopedic implants are made up of metals such as stainless steel, cobalt-chromium alloys, and titanium. Such implants are continuously exposed to corrosive and dynamic biological environments. These harsh environments can hamper the implant’s integrity and stability over time. Hydrophilic coatings create a highly lubricious layer on the surface of orthopedic implants, which acts as a protective barrier and prevents corrosion.
Meet Hydromer® – A Medical Device Coatings Manufacturer
Hydromer®, Inc. has 40+ years of experience in formulating, manufacturing, and supplying clinically proven medical coatings to OEM customers worldwide. Our goal is to allow our customers to focus on their core strengths and help you quickly bring advanced medical products to market.
We supply high-performance hydrophilic coatings for medical devices. Our coatings have highly sought-after performance attributes, such as:
- Drug-eluting capabilities
- Antimicrobial properties
- Wettability
- Biocompatibility
- Excellent lubricity (reduced device coefficient of friction)
- Low particulate
- Enhanced adhesion
- Thromboresistance reduces blood clotting
- Durability
- Compatibility with a wide range of medical devices
- Long-lasting hydrophilicity
Get in Touch
Do you need to develop a custom medical coating to meet your medical device requirements? If so, we can help regardless of what stage you are at in the product development process.
But what sets us apart from other coating manufacturers is the long list of support services we offer.
- Research and Development (R&D) services
- Contract coating services
- Worldwide supply of high-quality medical coatings
- Specialized Analytical Testing
- Custom Machine Building
- Turn-key Operations
- Technology Transfer Services
- Technical consulting and support services
Contact our team of experts today to learn more about our custom coatings and services.
