Choosing an Upper-Limb Prosthetic

The Benefits of Body-Powered Devices

When it comes to upper-limb prosthetics, choosing the right device is crucial for improving the quality of life and functionality of amputees. A recent systematic review by Carey et al. (2015) sheds light on the ongoing debate between the use of body-powered and myoelectric prostheses. This article explores the strengths and weaknesses of each type and underscores the importance of tailored training and rehabilitation in prosthetic adoption.

The Body-Powered Prosthetic: A Rugged and Reliable Choice

Body-powered prosthetic devices have long been favored for their robustness and reliability. These devices are mechanical and operate using cables and harnesses that the user manipulates through body movements. Body-powered prosthetics offer several significant advantages that make them an excellent choice for many amputees.

Pros of Body-Powered Devices:

 

• Durability: Ideal for use in wet, dirty, or rugged environments, making them perfect for active lifestyles and challenging conditions.
• Simplicity: Generally more straightforward to use and maintain, reducing the need for frequent repairs and ensuring consistent performance.
• Shorter Training Periods: Users can often become proficient more quickly compared to myoelectric devices, allowing for faster adaptation and integration into daily life.
• Cost-Effective: Typically less expensive than myoelectric devices, making them accessible to a broader range of users and reducing the financial burden on individuals and healthcare systems.

 

Cons of Body-Powered Devices:

 

• Less Aesthetic Appeal: They are often bulkier and less cosmetically appealing.
• Limited Functionality: May not provide the fine motor control needed for delicate tasks.

 

The Myoelectric Prosthetic: Embracing Technology

Myoelectric prosthetic devices represent a more advanced technological approach, using electrical signals from the user’s muscles to control movements. While they offer a more natural and intuitive user experience, they also come with certain limitations.

Pros of Myoelectric Devices:

 

• Better Cosmesis: These devices often look more natural and can be more socially acceptable.
• Improved Phantom Limb Pain: Users report a reduction in phantom limb pain.
• Preferred for Light-Intensity Work: Suitable for tasks that require more precision and finer motor control.

 

Cons of Myoelectric Devices:

 

• Fragility: More prone to breakage and can be unreliable in hot, humid environments or with weight fluctuations.
• Longer Training Periods: Require extensive training to master control.
• Environmental Limitations: Cannot be used in wet conditions, limiting their applicability in certain scenarios.
• Higher Cost: More expensive, which can be a significant barrier for some users.

 

Real-World Usage and Preferences

In practice, many amputees benefit from having access to multiple types of prosthetic devices. A study by Crandall and Tomhave (2002) found that 44% of pediatric patients preferred passive cosmetic hands, while only 15% opted for myoelectric devices. Interestingly, 41% of users utilized multiple types of devices daily, showcasing the need for versatility in prosthetic options.

Similarly, a survey of service members from the Operation Enduring Freedom/Operation Iraqi Freedom era highlighted the diverse needs of users, with many employing more than one type of prosthetic device daily (McFarland et al., 2010).

The Role of Training and Adaptation

Effective prosthetic rehabilitation is essential for successful device use. Research underscores the importance of therapy services and a team approach throughout all phases of prosthetic rehabilitation (Atkins, 2004; Management of Upper Extremity Amputation Rehabilitation Working Group, 2014).

Key Phases of Rehabilitation:

 

• Preprosthetic Training: Focuses on basic self-care skills and preparing the residual limb.
• Prosthetic Training: Involves education, controls training, and functional skills training. It helps users integrate their prosthesis into daily tasks and builds confidence in real-world situations.

 

Tailored Training for Success

Individualized prosthetic training, particularly when users find it useful, significantly enhances device acceptance. Training protocols should be adapted to the specific needs of the user, whether they are using a body-powered or a myoelectric device.

Emerging technologies like targeted muscle reinnervation and EMG pattern recognition control are pushing the boundaries of what prosthetic devices can achieve. However, these advancements also require specialized training to ensure users can fully benefit from the new capabilities.

Conclusion

Choosing between a body-powered and a myoelectric prosthetic device depends on the individual needs, lifestyle, and preferences of the user. While myoelectric devices offer advanced functionality and better aesthetics, body-powered devices stand out for their durability, simplicity, and cost-effectiveness. Effective training and a comprehensive rehabilitation approach are critical for maximizing the benefits of any prosthetic device.

Improving Prosthetic Acceptance

In an industry marked by a high abandonment rate of prosthetic devices, improving prosthetic acceptance is crucial. Many amputees discontinue using their prostheses due to discomfort, lack of functionality, or poor fit. At Marins Med, we focus on creating prosthetic devices that address these issues head-on, ensuring that users receive a product that enhances their quality of life and encourages consistent use.

The ProHensor (ProHook): Empowering Users

At Marins Med, our production positioning statement embodies our mission: The ProHensor (ProHook) serves to improve prosthetic acceptance by enhancing functionality and ensuring durability. Designed with a user-centric focus, this body-powered device can be quickly adopted, fits within medical insurance parameters, and remains affordable. The ProHook empowers users to play hard, work hard, and push boundaries.

Looking Ahead

At Marins Med, we believe in the power of continued innovation and personalized care to improve the lives of upper-limb amputees. By listening to the needs of users and investing in cutting-edge research and development, we aim to reduce prosthetic abandonment and enhance the overall user experience.

References:

 

• Carey, S. L., et al. (2015). Systematic review on myoelectric vs. body-powered prostheses.
• Crandall, R. C., & Tomhave, W. (2002). Long-term follow-up study of pediatric prosthetic use.
• McFarland, L. V., et al. (2010). Survey of service members with unilateral upper-limb amputation.
• National Academies of Sciences, Engineering, and Medicine. (2017). The Promise of Assistive Technology to Enhance Activity and Work Participation. Washington, DC: The National Academies Press. DOI: 10.17226/24740.