One of the primary anatomical differences between a child and an adult is the presence of apophysial or growth plates. Primary ossification of the tibia, calcaneus, cuboid, talus and phalanges often occurs by birth, while secondary ossification takes place later in childhood.
Ossification of the phalanges, metatarsals and navicular often do not occur until around 3 years; the calcaneus may not ossify until the age of 10 and the distal tibial physes asymmetrically ossifies around the age of 14.
Variations in paediatric injuries could be due to delayed physeal closure and the inherent cartilaginous nature of the bone in children.
In a study conducted by Boucher et al., significant differences were observed in the range of motion, stiffness and anthropometry of children between the ages of 6 and 10 years, highlighting the importance of developing more accurate anthropomorphic test devices in assessing paediatric ankle range of motion.
With the range of motion changing over the years, developmental differences in the paediatric population need to be considered while understanding the biomechanics leading to trauma or injury in a paediatric patient.
As compared to adults, newborns have double the dorsiflexion motion which decreases within the first five years of development, as established in a study by Cynthia C. Norkin and D. Joyce White in 2009.
The authors were also successful in determining how plantar flexion quickly progresses in newborns within the first few weeks of life.
There are two peaks that are observed in a mature gait in vertical loading during the stance phase - the first is at weight assumption and the second at propulsion - showing that the compression force is greater in magnitude than body weight.
In children, this loading pattern begins to emerge at the age of three years, gaining more definition by the age of five years.
The peak load pressure, particularly at the heel, increases between the ages of 18 and 48 months.
The developing power of the calf musculature, including the Flexor Hallucis Longus, is reflected in the increase in the magnitude of ankle power and decrease in hip and knee power during gait, which occurs around the age of five years.
The foot’s stability evolves along with its propulsive capacity in the context of the sagittal-plane function of walking.
A biomechanical evaluation should also include an assessment of genetically predisposing factors, which could potentially serve as contributing factors to foot/ankle pathologies.
Congenital and developmental conditions such as pes planus and tarsal coalition in children can be treated only by identifying and analysing these predisposing biomechanical factors and paying closer attention to conditions, which are fairly specific to the age of the child and unique to the growing paediatric skeleton.
Copyright 2016 MASS4D® All rights reserved.
Skateboarding is a popular recreational activity that involves the use of skateboards to navigate through challenging obstacles that are constructed in the form of elaborate ramps and other skate structures.