Passive Prosthesis: What You Should Know

In the realm of prosthetics, especially for upper limb amputations, passive prostheses are often overshadowed by their more technologically advanced counterparts. However, sometimes these devices offer distinct advantages that can significantly improve the lives of individuals with limb differences.

At PrimeCare, we've witnessed firsthand how prostheses can transform lives. Our team specializes in custom prosthetics in New Mexico and has extensive experience in fitting and customizing various types of prostheses. Let our compassionate experts guide you through the intricate world of passive prosthetics, helping you understand how these devices can meet your needs and lifestyle requirements.

What Are Passive Prostheses?

Passive prostheses are a type of prosthetic device designed to replace a missing limb. Unlike their active counterparts, such as body-powered prostheses or myoelectric devices, passive prosthetic devices don’t facilitate active movement. Instead, they focus on providing cosmetic restoration and basic functional support.

Key Features of Passive Prostheses

• Aesthetic Appeal: Passive prostheses often closely resemble natural arms to help users feel more comfortable in social situations.
• Lightweight Design: These prosthetic components are typically lighter than active prostheses, reducing strain on the user's residual limb.
• Low Maintenance: With fewer moving parts, passive prostheses generally require less upkeep than more complex devices.
• Cost-Effective: They are often more affordable than active prostheses, making them accessible to a wider range of users.

It's important to note that regardless of the type of prosthesis chosen, proper care and maintenance are crucial for ensuring longevity and functionality. This includes regular cleaning of the prosthesis and the residual limb.

Passive vs. Active Prostheses

What Do Passive Prosthetics Consist Of?

Passive prosthetics typically consist of the following key components:

1. Socket: Custom-fitted to the residual limb, ensuring comfort and secure attachment.
2. Prosthetic Liner (When Applicable): A cushioning layer worn between the residual limb and the socket, providing comfort and protection. Silicone liners are common in many prosthetic systems, including passive ones.
3. Suspension System: Keeps the prosthesis attached to the residual limb, often using suction or pin-lock mechanisms.
4. Structural Components: Form the frame of the prosthesis, providing support and shape.
5. Terminal Device: In passive prosthetics, this is often a cosmetic hand or a simple functional device like a hook.
6. Cosmetic Covering: Gives the prosthesis a lifelike appearance, often made from silicone for upper limb prosthetics.

Types of Passive Prostheses

Passive prostheses can be categorized based on the level of amputation and the specific needs of the user. While our focus at PrimeCare is primarily on upper limb prosthetics, it's worth noting that passive prostheses are available for various amputation levels in both upper and lower limbs. Here are some common types:

1. Cosmetic Prostheses

Cosmetic prostheses are designed primarily to restore the appearance of the missing limb. They are often made from advanced materials; for example, silicone prosthetics are particularly popular due to their lifelike appearance. These prostheses can be incredibly realistic as they feature details such as fingernails and even hair.

Cosmetic prostheses are available for various levels of limb loss, including:

• Hand or Partial Hand: These prostheses replace fingers or portions of the hand, helping to restore a natural appearance and sometimes providing passive function.
• Below the Elbow: Also known as transradial prostheses, these devices replace the forearm and hand.
• Above the Elbow: These transhumeral prostheses replace the entire arm from above the elbow down.
• Shoulder: For individuals with shoulder disarticulation or forequarter amputations, shoulder prosthetics can help restore body symmetry and appearance.
• Foot or Partial Foot: These prostheses replace toes or portions of the foot, aiding in restoring natural appearance and sometimes offering basic support.
• Below the Knee: Also known as transtibial prostheses, these devices replace the lower leg and foot.
• Above the Knee: These transfemoral prostheses replace the entire leg from above the knee down.
• Hip Prosthetics: For individuals with hip disarticulation, hip prosthetics can help restore body symmetry and appearance.

2. Passive Functional Prostheses

While they don’t enable active movement, passive functional prostheses can help with tasks like carrying objects or stabilizing items. They may include features such as:

• A prosthetic hand with a fixed grip
• A terminal device designed for specific activities (e.g., a hook for manual labor)
• An adjustable wrist unit for positioning the hand or terminal device
• Passive knee or ankle joints for lower limb prostheses that provide stability and basic support
• A prosthetic foot with a fixed ankle for lower limb amputees

3. Activity-Specific Prostheses

Some passive prostheses are designed for particular activities or hobbies. These activity-specific devices might include:

• Specialized attachments for sports (e.g., a golf club holder for upper limb prostheses)
• Tools for musicians (e.g., a device to hold a guitar pick)
• Workplace-specific attachments for various professions
• Waterproof options for swimming or water activities (for both upper and lower limbs)

The Direct Socket System can be applied to various levels of limb loss to offer improved comfort and fit for passive prosthesis users.

While many sports prostheses are active devices, some passive options exist for activities that require specific positioning or support rather than active movement.

It's also worth noting that many users opt for a hybrid approach, using both passive and active prostheses for different situations. These hybrid prosthesis solutions can provide the best of both worlds. For example, a person might use a body-powered prosthesis for work and switch to a cosmetic passive prosthesis for social events.

Choosing Between Active and Passive Prostheses

Deciding between a passive prosthesis and an active one (such as a body-powered prosthesis or a myoelectric prosthesis) depends on several factors:

1. Functional Needs: Consider your daily activities and whether you need active gripping and movement.
2. Comfort: Passive prostheses are often lighter, which can be more comfortable for all-day wear.
3. Cosmetic Concerns: If appearance is a priority, highly realistic passive prostheses might be better.
4. Cost and Maintenance: Evaluate your budget and willingness to maintain a more complex device.
5. Energy Expenditure: Active prostheses may require more physical effort to operate.

Conclusion: Embracing the Amputation Journey

Choosing the right prosthesis is a personal journey that involves considering your unique needs, lifestyle, and goals. Passive prostheses offer a valuable option for many individuals, providing a balance of functionality, comfort, and aesthetic appeal. Whether you're considering your first upper limb prosthesis or looking to expand your prosthetic options, one of the most important steps is understanding the world of passive prostheses.

At PrimeCare, a top prosthetics provider in New Mexico, we're committed to guiding you through this process, from initial fitting to ongoing care and maintenance. Our team of experienced prosthetists is ready to help you explore your options, find the perfect fit, and ensure you get the most out of your prosthetic device. Contact us today to schedule a consultation and take the next step in your prosthetic journey!