Vehicle architecture and child restraint design influence the position of children treated with hip spica casts

Kristy Brinker Brouwer, MS, CPST
Morgan Freshney, BS
Isabella Weingartz, BS
Nicole Matthews Papelain, BSN, RN, CPST
Jonathan Sheu, MD
Patrick Atkinson, PhD

Hip spica casts are commonly used for children aged 6 months to 5 years as an effective treatment for femur fractures and developmental hip dysplasia. While the spica cast is advantageous due to its non-invasive and conservative methodology, it can render transportation difficult. Past crash testing studies have shown that the child restraint shape and cast design significantly influence the positioning of the restrained child. One major drawback of these investigations was that all testing was performed on the same, simulated vehicle seat, as required by FMVSS 213. It was unknown how children fitted with hip spica seats would be positioned in actual vehicles. This was due to the design of 213 vehicle seat which allows unrestricted access from all directions. In contrast, access to seating positions in actual vehicles are constrained by adjacent features such as doors, nearby seats, and rear glass in the case of typical cars and pickup trucks. The current study was designed to investigate if children treated with a hip spica cast can be properly restrained in different child restraints in a range of typical vehicles.

Common vehicles representing a range of interior architectures were studied: 2-row truck, minivan, SUV, and compact car. Two crash test dummies (1 and 3 year-old) were used as child surrogates. Two child restraints (Merritt Wallenberg, Diono Radian R100) were investigated for the rear-facing and forward-facing configurations. An additional restraint (Ride Safer vest with or without the BubbleBum booster) was also studied for the forward facing 3 year-old. Casts typically utilized to treat bilateral hip dysplasia and femur fractures were applied to the dummies during which the positioning of the dummies body and lower extremities were maintained with a hip spica casting table. A third “walking” hip spica femur fracture cast was also created. A test matrix was created that attempted to properly restrain the two children in the different vehicles, in the different child restraints, while fit with each of the 3 hip spica casts.

The forward-facing 3 year-old was safely restrained in nearly all test configurations. All hip dysplasia casts were safely restrained while 67% of femur fracture and walking casts were safely restrained. In contrast, the rear-facing 1 year-old was only safely restrained in the hip dysplasia cast, femur fracture cast, and walking cast at a frequency of 87.5%, 12.5%, and 37.5%, respectively. The minivan was associated with greatest number safely restrained configurations.

The current study documents that certain combinations of vehicle, child restraint design, rear- or forward-facing direction, and spica cast type influence the safe restraint of a child. Of note, the hip dysplasia cast can be restrained safely in nearly all cases, regardless of the variation in independent test parameters. In contrast, the cast typically used to femur fracture cannot be safely restrained in all cases, with forward-facing yielding more success than rear-facing.

1. There are differences between the hip dysplasia and femur fracture spica casts.
2. Common reasons for improper restraint include head-neck-spine misalignment and reduced pulmonary function.
3. The minivan was associated with greatest number safely restrained configurations.

The future is upon us: Automated driving keeps families safer

Kristy Brinker Brouwer, MS, CPST
Joseph M. Colella, CPST-I

Advanced Driver Assistance Systems (ADAS) and Automated Driving Systems (ADS) show great promise for reducing motor vehicle injuries and fatalities. Human error contributes to 94% of crashes, while the evolution of driver assistance features and full autonomy have the potential to reduce human error, overall crashes and crash severity. As these technologies are developed and implemented, however, it is crucial that the unique safety needs of children and families are prioritized. The Safe Kids in Advancing Vehicles Alliance (SKAVA) has been formed to facilitate stakeholder discussion, collaboration, and action toward enhancing the safety of children as these technologies evolve, thereby reducing the risk of injury and death. SKAVA has developed a child-focused Design Failure Mode & Effects Analysis (DFMEA) for identifying potential risks introduced in automated mobility. With the current advancement of automated vehicles and autonomous ride-share vehicles arriving in the near future, we will take an engaged deep dive into what a child-focused DFMEA would look like for this emerging technology, as well as, collecting and implementing feedback from the attendees.

1. Examine how the unique needs of children should be considered in Automated and Autonomous Vehicle design, development, and testing.
2. Describe the purpose, methodical approach, and outcomes of a Design Failure Mode & Effects Analysis.
3. Analyze potential risks to child passengers and identify their likely causes in Autonomous Ride-Share Vehicle scenarios.
4. Identify the available tools for educating about, advocating for, and the monitoring progress of child safety in and around Automated Vehicles.