Pediatric Positioning: Hey Wheelchair Man, How Small Can You Go?

Craig Kraft, BS, ATP/SMS & Richard Besett, ATP

Working in a busy pediatric orthopedic clinic provides daily opportunities for recommending and providing seating and mobility equipment. As the ATP/SMS certified seating specialist1 at Tampa Shriners Hospital for Children, challenging requests are routinely encountered to meet the orthopedist's goals to correct, prevent, or support for structural deformity and skin problems; while at the same time ensuring the child's functional ability to propel a manual chair or drive power chair is not compromised. To ensure the favorable outcomes, multiple pieces of information from everyone involved with the child must be considered. What is the optimal outcome? This results when everyone's needs are identified in the initial equipment assessment are satisfied. Who is everyone? Not only are the orthopedist and therapist recommendations essential, equally important are the child's needs, the family structure and activities, community activities, transportation requirements, school and home environment access. Sometimes, augmentative communication or computer access must also be considered and integrated with the seating and mobility equipment.

Recently, a special child who exemplifies the complexity and multiple needs of the population served in our clinic required a new seating system to meet his functional, positional and orthopedic goals. Rayland, a 15 month old male, has a diagnosis of Rhizomelic Chondrodysplasia Punctata Type 1 often called RCPD.2 RCPD affects fewer than 1 in 100,000 people worldwide and is more common than RCPD 2 and RCPD 3. RCPD results from mutations in one of three genes. Mutations in the PEX7 gene which is most common and results in RCPD. Changes in the GNPAT gene lead to RCPD2, while AGPS gene mutations result in RCPD3. The genes associated with RCPD are involved in the formation and function of structures called peroxisomes. Peroxisomes are sac-like compartments within cells that contain enzymes needed to break down many different substances, including fatty acids and certain toxic compounds. They are also important for the production of fats (Lipids) used in digestion and in the nervous system. RCPD is a condition which impairs the normal development of many parts of the body. The major features of this disorder include skeletal abnormalities, distinctive facial features, intellectual disability, and respiratory problems. Most children with this condition do not achieve developmental milestones such as sitting without support, feeding themselves, or speaking in phrases. Affected infants grow much more slowly than other children their age, and many also have seizures.

This patient was referred to our clinic by his therapist with concerns about his hip position resulting in decreased range of motion. The family was also concerned about his hands and feet. The patient is followed by Genetics, receives therapies on a regular basis, and has lately been hospitalized for respiratory issues. He has a gastrostomy tube (G-Tube) and has a history of multiple eye surgeries to treat bilateral cataracts.

The medical staff conducted a physical exam and noted shortened humeri and femora, rib cage asymmetry, bilateral upper and lower extremity joint contractures, particularly at the shoulders, elbows and hips; however, his feet were in a neutral position and were flexible. The patient's skin is intact. Due to his preferred hand and wrist positioning upper extremity splints were recommended. More significant were the results of his x-rays. He had a 30 degree right thoracolumbar positional curve which could be reduced approximately 50 percent with corrective hand forces simulating thoracic lateral supports. The radiograph of the pelvis showed a lack of formation of the femoral heads. The femora were quite widened and shortened with calcifications noted, consistent with his diagnosis. As a result from his clinic visit, the patient was referred to Occupational Therapy for hand splints and for a Seating evaluation for improved positioning in his Convaid Cuddle Bug 2 Wheelchair.3

Upon initial assessment, a Convaid Cuddle Bug 2 Wheelchair (HCPCS code of #E1232), classified as a compact folding tilt in space wheelchair would appear to be a good choice with supportive seating. However, the one provided was simply too large to fit his body correctly for upright midline sitting alignment because the seating supports could not be adjusted for his small size. (See Table )

As a result, the family was forced to keep the seat to back angle open and the seating system tilted back to keep him comfortable and prevent him from leaning over. He was literally looking at the ceiling. A challenge was presented to us on how to meet positioning and functional needs as this system could not be modified to meet his needs and there were only a few commercially available products on the market to accommodate his size. One option discussed was a custom sized Jay Sure Fit Lil Kiddos® seating system4 mounted in a pediatric tilt wheelchair base. However, this did not meet the family's requirements for the stroller base style. We considered the Otto Bock NUTEC seating system5 although when comparing the pricing to our cost to fabricate we opted to build our own. The available funding has been exhausted and with the authorization of the Cuddle Bug 2 those replacement costs fall on our shoulders. Instead, we decided to offer an in-house custom made seating system on a commercially available Otto Bock Kimba Spring stroller base we had in stock.

The custom made seating insert consisted of a padded I-cut backrest and cushion using AliMed® T-Foam™ 6 one inch soft foam package. Custom made thoracic lateral pads with Lil Kiddos® mount hardware and custom made chest harness were fabricated. The upholstery covers for the backrest and planer seat cushion consisted of Dartex®7 on the weight bearing surface. It is a waterproof 4-way stretch breathable fabric sewn into Naugahyde side panels and backing to cover the seat and backrest cushions. We installed a Stealth Niño head bumper and single sub-occipital support QCR #SU118. The headrest mount is the multi-axis removable headrest mount8 system. We fabricated an adjustable height and depth solid back and seat base with one piece footplate made from Starboard® plastic from the King Plastic Corporation in ¼" thickness.9 Adjustable width and height thoracic lateral pads and adjustable width hip pads were incorporated. A custom cutout Lexan® tray10 was fabricated.

We estimate eight man hours of labor was involved in addition to the cost of commercial components and fabricated materials we estimate our cost for the seating insert and tray is nine hundred and forty dollars. This cost is approximately half of the cost of comparable commercial options that were available. The Otto Bock Kimba Spring base was donated from the community for this very purpose.[Image ]

The custom seating insert was modified on the bottom to accept the Otto Bock quick release system that interfaces to the Otto Bock Kimba Spring base.11 The Otto Bock commercial canopy was used for those sunny or rainy Florida summer days. Our custom seating system is able to operate exactly the same as the Otto Bock commercial seating system offerings. Pulling the lever on the quick release interface allows us to remove the custom seating system and allow folding of the base. We instructed the family to continue to use the child's car seat for transportation as our fabricated seating insert is not crash tested.

Upon initial fit for his new tilt in space seating system, the patient was able to sit upright with spinal alignment and maintained midline head, trunk, and pelvic positioning to meet the need for orthopedic support. Secondarily, because his trunk was in a more extended position his diaphragm had the potential to function more normally to facilitate deeper breathing and increased air to lung volume. This position also benefits digestion.12 He now had the option to work on head and trunk control in an upright position and use his hands for grasping and other developmentally appropriate activities with the tray. [Image ]

The custom chest harness required modification to lower the cross strap and buckle away from his throat. Custom extended plastic tray mounts and elbow pads need to be made to raise his tray height closer to his elbow height to promote developmental activities. No wheelchair man is perfect.

Feedback ensures growth and learning which will contribute to improved strategies, techniques and appropriate recommendations of products to meet the needs of our patients. The patient's grandfather wrote to us,

"With tears in my eyes I want to say thank you!!!! As my grandson is 18 months old now, this is the first time he has been able to sit up on his own (well with the help of his new chair) and see the world. Your seat specialist and Dr.'s at the Tampa facility are the most awesome people. Y'all have given him something we would never had been able to afford. His new chair is just just.....well I don't have words to say. Again, thank you and all the staff there."

By using all the information available from each stake holder and prioritizing everyone's needs, in this case the desired outcome was successfully reached and our costs were ultimately reduced.

Craig Kraft & Richard Besett are affiliated with Shriners Hospital for Children Tampa


  1. Rehabilitation Engineers Society of North America (RESNA) Certifications
  2. Genetics Home Reference, Rhizomelic Chondrodysplasia Punctata, Conditions
  3. Convaid Cuddle Bug 2 Wheelchair
  4. Sunrise Medical JAY SureFit Lil' Kiddos®
  5. Otto Bock NUTEC Seating Order Form
  6. AliMed® T-Foam Cushions™
  7. Dartex USA, Dartex® Polyurethane Coated Fabrics
  8. Stealth Headrest Systems
  9. King Plastic Corporation, STARBOARD® HDPE Plastic
  10. Chemistry That Matters, SABIC Inc., Lexan® Polycarbonate Resin
  11. Otto Bock Kimba Spring mobility base
  12. Davis, D., (2011) Seating and Respiratory Function, Cerebral Palsy Alliance, Techno Talk Newsletter, Volume 20 – Issue 1 – February 2011