The AAD Wheelchair represents a breakthrough in mobility solutions for individuals who have limited or no movement in their legs. This Patented wheelchair is designed and engineered to foster coordinated movement between the upper and lower limbs through the midline, to promote healthy alignment, and to support user independence. The AAD wheelchair can be operated both manually and mechanically for paraplegic and quadriplegic users.

The AAD Wheelchair’s Patented features include a unique gearing system and an innovative seat and back design. These features can offer a transformative experience for individuals with spinal cord injuries, Spina Bifida, Cerebral Palsy and other conditions that affect mobility.  By supporting and promoting contralateral reciprocal movement, the natural alignment of the spine and lower limbs, enhancing upper and lower body mobility, and stimulating muscles, ligaments, tendons, and joints that might otherwise remain inactive. Collectively, these features empower users to lead more active and independent lives.

Contralateral Reciprocal Movement Mechanism

At the heart of the AAD Wheelchair is its unique gearing system located beneath the seat. This system enables users to generate movement in their lower limbs through the coordinated action of their upper body. Specifically, when a user moves a hand on one side of their body either manually or mechanically, the gearing system extends the leg and foot on the opposite side. This creates contralateral reciprocal movement, meaning that the arms and legs move together in a coordinated pattern across the midline of the body. Such motion is especially beneficial for wheelchair users with SCI, CP, SB, MS, EDS and other conditions that affect mobility as it stimulates muscles, ligaments, tendons, and joints that might otherwise remain inactive and  promotes the synaptic strengthening and neural reorganization of the brain from contralateral reciprocal movement of the lower limbs. 

Enhanced Arm Mobility and Core Muscle Engagement

Unlike conventional wheelchairs, the AAD Wheelchair allows the arms to swing backward behind the body while keeping the head upright, aligned and centered over the body. This expanded range of motion engages both the flexor and extensor muscle groups around the top of the spine and beneath the shoulder blades and the core muscles on the front of the chest and abdomen. Such engagement supports upper body strength and flexibility, further contributing to overall mobility and well-being.

Ergonomic Backrest for Proper Spinal Alignment and Support

Unlike traditional wheelchairs, the design of the AAD wheelchair’s backrest is tailored to support the natural alignment and curvature of the cervical (neck), thoracic (mid-back), and lumbar (lower back) regions of the spine. By providing this comprehensive support, the wheelchair helps users maintain an upright, centered head position, reducing spinal strain during use. Spinal alignment is crucial for both daily functionality and long-term spinal health.

Ergonomic Seat for Proper Lower Limb Alignment

The unique shape of the contoured seat ensures that the knees and ankles remain aligned directly under the hips. This alignment not only supports a healthy upright seated posture but also makes it easier for users to transfer into and out of the wheelchair, enhancing user autonomy and safety. The wings on the back of the seat help users who can stand rise from a seated position and stand comfortably behind the wheelchair.

Weighted Footrests With Protective Toe guards

 The footrests of the AAD wheelchair footrests have toe guards to protect the front of the foot from trauma. The telescoping, height adjustable pivoting and weighted footrests aid in the user maintaining the heels of their feet lower than their toes during locomotion reducing Achilles tendon contracture and increasing the ability of the foot in dorsiflexion.

Health Risks and Musculoskeletal Changes in Wheelchair Users

Reduced Mechanical Stress: Effects on Bone Metabolism and Growth

Mechanical stress from activities like walking and standing is crucial for bone health. It stimulates bone remodeling and growth through weight-bearing and muscle contractions. In wheelchair users, reduced mechanical loading leads to decreased bone density and impaired bone metabolism. This condition, known as disuse osteoporosis, increases fracture risk and slows bone healing. Children who use wheelchairs may experience stunted bone growth and musculoskeletal deformities due to insufficient stimulation during development.

Impact of Loss of Coordinated Movement Between Arms and Legs After SCI and in Children With CP and SB

Contralateral patterns are observable in the earliest stages of normal motor development. Crawling, for instance, is essential for establishing the cross-body connections that support later movement and cognitive function. Activities that engage both sides of the body foster brain development, hand-eye coordination, musculoskeletal health and even emotional regulation. Normal movement and motion involve coordinated activity between the arms and legs through the midline of the body, which helps maintain musculoskeletal health and metabolic balance. Wheelchair users often lose this coordinated movement, especially if lower limb paralysis is present. This disruption can increase the risk of chronic diseases in adult wheelchair users, such as obesity, diabetes, and cardiovascular disease, due to decreased overall physical activity. The lack of contralateral reciprocal movement between the arm on one side of the body and the leg and foot on the other side of the body also leads to imbalances in muscle tone and joint function, contributing to further health complications in children and adult wheelchair users.

Muscle and Tendon Changes: Atrophy and Degeneration

Muscle atrophy is a common consequence of reduced movement. When muscles are not regularly engaged, they shrink in size and lose strength. Tendons also degenerate, becoming less elastic and more prone to injury. These changes result in decreased function and increased risk of contractures—permanent tightening of muscles, tendons, and ligaments. Over time, muscle imbalances can develop, making transfers, independence and self-care activities more difficult.

Physical Changes in Paralyzed Limbs

Paralyzed limbs from SCI undergo several physical changes. Atrophy leads to muscle wasting, while contractures may limit joint mobility. Swelling, or edema, can occur due to poor circulation and lack of movement in the legs and feet. Sensory changes are also common, with reduced sensation increasing the risk of pressure injuries and wounds. In severe cases, these changes can make limb care and hygiene challenging, requiring specialized interventions.

Mechanisms of Bone Loss at the Cellular Level

Bone loss in wheelchair users is driven by cellular mechanisms involving osteoclasts and osteoblasts. Osteoclasts break down bone tissue, while osteoblasts build it up. Reduced mechanical stress shifts the balance toward bone resorption, as osteoclasts become more active and osteoblast activity decreases. This imbalance leads to decreased bone mass and structural integrity, increasing the risk of fractures and delayed healing.

Importance of Kinetic Chain Alignment and Contralateral Reciprocal Movement

The kinetic chain refers to the interconnected system of muscles, ligaments, tendons bones, and joints that work together during movement. Proper alignment and contralateral (opposite side) reciprocal movement are crucial for distributing forces efficiently and preventing injury. In wheelchair users, altered movement patterns can disrupt kinetic chain alignment, leading to compensatory strategies that strain the upper body and increase the risk of overuse injuries, especially in the shoulders and wrists.

Impact of Reduced Weight-Bearing Activities on Bone and Muscle Health

Weight-bearing activities are fundamental for maintaining bone density and muscle mass. Without regular standing, walking, or load-bearing exercises, wheelchair users face accelerated bone loss and muscle weakening. This not only increases the risk of osteoporosis and fractures but also reduces overall mobility and independence. Rehabilitation programs that incorporate standing frames or weight-bearing activities can help mitigate these effects.

Immobility and Chronic Disease Risk

Prolonged immobility affects more than just the muscles and bones; it has systemic consequences. Reduced physical activity impairs glucose metabolism and increases insulin resistance, raising the risk of type 2 diabetes in adults. Immobility is also linked to a higher incidence of cardiovascular disease, as blood circulation slows and metabolic rates drop. Furthermore, sedentary lifestyles contribute to weight gain, and a higher fat to muscle ratio even in wheelchair users who are not overweight which can exacerbate existing health problems and limit mobility even further.

US Patent Office Utility Patent 12,257,196 Date of Patent: Mar. 25, 2025.