The material used for surgical screws directly affects patient safety, healing time, and implant durability. Titanium is widely favored for its strength, corrosion resistance, and biocompatibility.
However, alternatives like stainless steel are still used in certain procedures. Each material brings distinct properties that impact performance under different surgical conditions. A clear comparison helps in choosing the most appropriate option for specific clinical needs.
What Are Surgical Screws?
Surgical screws are made as orthopedic implant devices to fix bones and hold implants due to their high functioning. Surgical screws come in many configurations for specific uses, such as cancellous screws for the use in spongy bones or cortical screws for the use in dense bones.
The screws may be alone or used along with other implants like plates in order to yield beneficial stabilization and bone healing.
Materials Used In Surgical Screws
Surgical screws are important devices in orthopedic and trauma surgery. It is intended to stabilize bones and assist in healing following fractures, reconstructions, or implantations.
The performance, compatibility, and durability of the screws significantly rely on the materials used to make them. The following are the major materials used and their properties:
1. Titanium and Titanium Alloys
Titanium is most used material in modern surgical screws. Titanium is known for its excellent biocompatibility. It is one of the numerous materials used as a permanent body implant. It is appreciated for its:
- Biocompatibility: Titanium is resistant to corrosion and is well tolerated by the human body. This minimize the risk of unwanted immune reactions.
- Strength-to-Weight Ratio: It possesses great mechanical strength with minimal weight, and this is useful in weight-bearing orthopedic implants.
- MRI Compatibility: Titanium is not ferromagnetic, therefore, it does not affect MRI imaging. Thus, it is MR safe for patients who may require MRI scans post-surgery. Consequently, it is in great demand in patients with a high level of ongoing imaging requirements.
Titanium alloys (e.g., Ti-6Al-4V) are usually preferred over pure titanium to enhance the mechanical properties without sacrificing corrosion resistance and biocompatibility.
Titanium screws are popular for their strength, durability, and resistance to corrosion. They do loosen or break due to mechanical stress, bone healing problems and poor installation.
2. Stainless Steel
Stainless steel was once the material of choice for surgical screws and continues to be so in some applications due to its availability, high strength and affordability. Its main characteristics are:
- High Mechanical Strength: It can be used in high-load applications, particularly where temporary fixation is required.
- Cost-Effectiveness: Less expensive than titanium, thus a standard in public healthcare systems or temporary implants.
- Drawbacks: Stainless steel is more corrosive in the long term and can cause interference with imaging modalities such as MRI. It is also denser than titanium. Thus, it is not suitable for long-term implantation in sensitive patients.
Stainless steel is not as biocompatible as surgical titanium and may not corrode as slowly over time.
3. PEEK (Polyether Ether Ketone)
PEEK is not a metal but a high-performance polymer that is becoming increasingly popular in certain surgical procedures. It is generally utilized in:
- Non-Metallic Implant Systems: It proves to be extremely useful in case of cranial, spinal, and orthopedic trauma when the clarity of imaging is absolutely necessary.
- Radiolucency: Its flexibility derives from its characteristic of radiolucency, as it does not appear on X-rays and CT scans. Thus, the physician can observe the healing process without any hindrance.
- Biocompatibility: It is inert and does not easily increase inflammatory reactions.
But PEEK is not as mechanically strong as metal, so it’s mostly used in conjunction with other materials or for low-load bearing functions.
4. Bioabsorbable Materials
These include biodegradable polymers like polylactic acid (PLA), polyglycolic acid (PGA), or a mixture like PLGA. Bioabsorbable screws are unique because it uses materials like polylactic acid. It is also made to dissolve in the body over time. They are utilized for:
- Temporary Fixation: These screws are often used in children’s surgery, sports injuries or facial bone surgery and in situations where a permanent implant is not preferable.
- Benefits: On the one hand, it avoids the second procedure of screw removal. On the other hand, it minimizes chronic foreign body content in the body.
- Limitations: It has less mechanical strength and unsuitable for high-load-bearing applications. Also, it increase the risk of inflammatory reactions in certain patients.
Surgical Screw Material Selection
| Factor | Titanium / Titanium Alloy | Stainless Steel | PEEK (Polyether Ether Ketone) | Bioabsorbable Polymers (e.g., PLA, PGA) |
| Implant Duration | Best for permanent implants | Suitable for temporary implants | Used for non-load-bearing permanent implants | Ideal for temporary use, dissolves over time |
| Mechanical Strength | High strength, fatigue-resistant | Very high strength | Moderate strength, suitable for low-load applications | Lower strength, not suitable for high-load areas |
| MRI / Imaging Compatibility | MRI-compatible, does not interfere with imaging | May cause imaging artifacts or be unsafe in MRI | Radiolucent – ideal for clear X-ray/CT/MRI imaging | Generally safe; may appear faint in imaging |
| Biocompatibility | Excellent – highly tolerated by most patients | Good, but contains nickel, which can cause allergic reactions in some | Very good – inert and well-tolerated | Good – designed to dissolve safely in the body |
| Application Area | Load-bearing bones, spine, joints, trauma repair | Cost-sensitive procedures, temporary fixation | Cranial, facial, hand surgeries, pediatric cases | Pediatric fractures, sports injuries, and facial surgeries |
| Patient Considerations | Best for metal-sensitive patients and long-term stability | Not ideal for patients with nickel allergy | Good for patients needing frequent imaging or with metal sensitivity | Ideal for children or patients where reoperation is undesirable |
| Cost | High | Low | High | Moderate to high |
| Removability | Permanent, needs surgical removal if required | Permanent, needs surgical removal | Permanent, may require removal if complications occur | No removal needed – material dissolves naturally |
Conclusion
So, are all surgical screws made of titanium? No. Although widely utilized due to superior mechanical and biological properties, titanium is merely one among a number of materials that can be used to address diverse surgical needs.
A more cost-effective alternative for temporary implants is stainless steel, PEEK is superior for imaging-sensitive surgery, and bioabsorbable alternatives make hardware removal obsolete.
Selecting the appropriate material for surgical screws is not a universal choice—it varies with surgery type, implant longevity, patient sensitivity, and post-operative needs.
Knowing the distinct advantages of each option allows patients and healthcare professionals to make sound decisions that facilitate safe healing and successful long-term results.
