Neck Exoskeleton: Risks, Precautions and Best Practices

What is a Neck Exoskeleton? Definition and How It Works

In response to the rise in work-related musculoskeletal disorders (MSDs) linked to poor posture, technological innovation is offering increasingly targeted solutions. Among these, the neck exoskeleton is emerging as a promising tool to relieve the cervical region. But what exactly is it? Let's dive into the heart of this technology.

Definition and Types of Cervical Exoskeletons

A neck exoskeleton is a wearable device designed to support the head and neck. Its primary goal is to reduce muscle strain when the user maintains a prolonged posture, particularly in forward flexion (head bent down) or extension (head tilted back). Unlike a simple cervical collar that immobilises, a cervical exoskeleton assists movement while preserving mobility.

There are two main categories:

• Passive exoskeletons: These operate without an external power source. They use springs, dampers, or elastic systems to store and release mechanical energy. When the user bends their head, the device stores energy and releases it to support the return movement. These models are generally lighter, less expensive, and require no battery maintenance.
• Active exoskeletons: Also known as motorised exoskeletons, these incorporate sensors, motors, and a battery. They detect the angle of the head and activate a motor to provide precise assistance force. These models offer more dynamic and adaptable support but are heavier and require regular recharging.

It is important to note that the cervical exoskeleton focuses exclusively on the neck and head region. This distinguishes it from leg exoskeletons, such as those developed by Exyvex, which target the lower limbs to reduce fatigue during walking or carrying heavy loads.

How Does a Motorised Cervical Collar Work?

The operation of an active neck exoskeleton relies on an intelligent feedback loop. Angle sensors, often placed on the strap or joint, measure the tilt of the head relative to the torso in real-time. This data is transmitted to a microprocessor that calculates the necessary support force.

The weight of the human head is approximately 5 kg. In an upright position, the neck muscles support it naturally. However, when the head tilts to 30 degrees, the effective load on the cervical vertebrae can reach the equivalent of 18 kg. At 60 degrees, it exceeds 27 kg. The exoskeleton compensates for this overload by applying a counter-support force via cables or actuators.

Passive models, on the other hand, use a different principle. A friction system or a helical spring is calibrated to provide a support force proportional to the angle of flexion. The more the head bends, the greater the spring's resistance. Some advanced devices even incorporate artificial intelligence algorithms that learn the wearer's movement patterns to adjust assistance in real-time, offering a more natural and less intrusive experience.

Why is a Cervical Exoskeleton Crucial for Professionals?

Cervical MSDs represent a major public health issue in many sectors. The neck exoskeleton is not a gadget but a concrete response to well-identified professional problems.

The Most Affected Sectors

Certain professions are particularly exposed to stressful neck postures:

• Surgeons and dentists: They spend hours leaning over their patients, often in uncomfortable positions. Studies show that over 80% of surgeons suffer from neck pain during their careers.
• Welders and assembly line operators: Their work involves repetitive static postures, with prolonged neck flexion to inspect parts or perform welds.
• Craftspeople (jewellers, watchmakers, cabinetmakers): Their precision work requires constant head tilting to see details, which heavily strains the cervical muscles.
• Hairdressers and beauticians: They often work standing up, leaning over their clients, leading to chronic tension.

Concrete Benefits for Health and Productivity

The benefits of the cervical exoskeleton are multiple and measurable:

• Reduced muscle fatigue: Recent studies indicate a 30-50% decrease in electromyographic activity of the trapezius and cervical muscles when using a neck exoskeleton. This translates to less fatigue at the end of the day.
• Prevention of chronic pain: By reducing the mechanical load on intervertebral discs and ligaments, the exoskeleton helps prevent the onset of herniated discs, cervical osteoarthritis, and muscle contractures.
• Improved concentration and precision: When the body is not constantly fighting pain, the mind can focus on the task. Surgeons report better dexterity and fewer errors during long procedures.
• Reduced sick leave: Companies that have introduced cervical exoskeletons observe a significant decrease in MSD-related absences, representing a tangible return on investment.

How to Choose a Neck Exoskeleton Suited to Your Job?

Choosing a neck exoskeleton should not be taken lightly. It must match both the user's morphology and the specific constraints of their workstation.

Essential Selection Criteria

Here are the key points to evaluate before a purchase:

• Weight: The device should be as light as possible (ideally under 1 kg) to avoid adding extra strain to the neck. A too-heavy exoskeleton could worsen fatigue instead of reducing it.
• Battery life (for active models): The battery must last at least a full working day (8 hours) to avoid interruptions. Some models offer 10 to 12 hours of autonomy.
• Comfort: Materials should be breathable to prevent excessive sweating. Straps and contact points must be padded and adjustable to fit all body types.
• Adaptability to the task: The exoskeleton should not hinder normal movements. It should be able to be deactivated or put into standby mode when the user moves or changes posture.
• Ease of donning: Putting on and taking off the device should be quick and intuitive, without requiring assistance.

Comparison with Other Ergonomic Solutions

The neck exoskeleton should not be confused with other devices:

• Passive cervical collars (neck braces): These medical devices are designed to immobilise the neck after trauma. They are not suitable for work as they limit mobility and can lead to muscle wasting.
• Head supports: Some helmets or visors incorporate an adjustable headrest, but they do not provide dynamic assistance like an exoskeleton.
• Workstation adjustments: Ergonomic chairs, articulated arms for screens, or binocular loupes can help, but they do not correct neck posture when it is bent. The cervical exoskeleton complements these solutions without replacing them.

For a more detailed comparison, here is a summary table:

Testimonials and Case Studies: The Cervical Exoskeleton in Action

Beyond the numbers, it is the real-world feedback that best illustrates the impact of the neck exoskeleton on professionals' daily lives.

Use Case Among Surgeons

Dr. Martin, an orthopaedic surgeon in Lyon, shares his experience: "After 6 months of using a cervical exoskeleton, my neck pain decreased by 70%. I can now perform 4-hour procedures without feeling that burning sensation in my neck that used to force me to take breaks."

A clinical study conducted at a university hospital measured trapezius muscle activity during 2-hour procedures. Results showed a 40% reduction in muscle activity with the exoskeleton, compared to a 15% increase without it. Surgeons also reported better sleep quality and fewer tension headaches.

Application in Industry and Welding

In a metal fabrication plant, a 45-year-old welder shares his experience: "Before, I had to stop every 30 minutes to stretch my neck. Now, I can work 8 hours without feeling stiff. My back also thanks me because I compensate less with my shoulders."

Company data shows a 25% decrease in cervical MSD-related absences in the workshop where exoskeletons were introduced, compared to stagnation in other workshops. The return on investment was estimated at 18 months, thanks to reduced compensation costs and increased productivity.

Limitations and Precautions: What You Need to Know Before Buying

While the neck exoskeleton is a powerful tool, it is not a magic wand. It is important to understand its limitations to integrate it effectively into a prevention strategy.

Contraindications and Potential Risks

Before adopting a cervical exoskeleton, certain points should be considered:

• Medical contraindications: Individuals with severe cervical pathologies (unstable herniated discs, advanced osteoarthritis with instability, recent fractures) should not use this type of device without prior medical advice. The assistance could mask symptoms or worsen an injury.
• Risk of muscle dependency: Exclusive and continuous use can lead to atrophy of the neck stabiliser muscles. It is recommended not to wear the exoskeleton for more than 6 to 8 hours per day and to perform muscle-strengthening exercises outside of work.
• Compensatory poor postures: Without adequate training, the user might adopt incorrect postures (e.g., arching the back to compensate for neck support). Guidance from an ergonomist is essential.

Integration into a Comprehensive Prevention Approach

The neck exoskeleton is a tool, not a miracle solution. To be fully effective, it must be part of a holistic approach:

• Active breaks: Alternate periods of wear with 5-minute breaks every hour to move your head, shoulders, and back.
• Stretching exercises: Incorporate neck stretches and mobility exercises into your daily routine.
• Workstation ergonomics: Adjust the height of your chair, work surface, and screens to minimise neck flexion as much as possible.
• Medical follow-up: Regularly consult an occupational health physician or physiotherapist to evaluate the device's effectiveness and adjust its use if necessary.

In conclusion, the neck exoskeleton represents a significant advancement in the prevention of cervical MSDs. When chosen well, used correctly, and integrated into a comprehensive approach, it can transform the professional lives of many workers. If you are affected by neck pain at work, do not hesitate to consult an ergonomist to assess whether this solution is suitable for your situation.