This prospective 3D motion analysis study determines the elbow flexion/extension and forearm pronosupination that children (ages 6–11) and adolescents (ages 12–17) actually use to perform 8 functional and 4 contemporary tasks. It is the first such dataset in a pediatric population, filling a gap left by Morrey et al. (1981), whose adult-derived functional arc had been extrapolated to children without validation.
Every pediatric elbow treatment goal has been built on Morrey's 1981 adult data — a study that included zero children. This paper is the first to measure what children and adolescents actually need at the elbow to function.
For most tasks, the Morrey arc still holds: target 30–130 degrees of flexion and 50–50 degrees of pronosupination when treating a posttraumatic contracture in a child, and you will cover the majority of daily activities.
When your patient is a smartphone user or a student who types, raise the bar. Cell phone use requires 148 degrees of flexion and a 107-degree pronosupination arc. Keyboard use demands 65 degrees of pronation. Stopping at the Morrey arc will leave these patients functionally limited for their most frequent daily tasks.
One important caveat from the authors: findings apply to typically developing children after trauma. For congenital conditions like proximal radioulnar synostosis, compensatory shoulder motion may allow function with far less elbow arc. Do not apply these thresholds rigidly to congenital deformity.
This prospective 3D motion analysis study determines the elbow flexion/extension and forearm pronosupination that children (ages 6–11) and adolescents (ages 12–17) actually use to perform 8 functional and 4 contemporary tasks. It is the first such dataset in a pediatric population, filling a gap left by Morrey et al. (1981), whose adult-derived functional arc had been extrapolated to children without validation.
Every pediatric elbow treatment goal has been built on Morrey's 1981 adult data — a study that included zero children. This paper is the first to measure what children and adolescents actually need at the elbow to function.
For most tasks, the Morrey arc still holds: target 30–130 degrees of flexion and 50–50 degrees of pronosupination when treating a posttraumatic contracture in a child, and you will cover the majority of daily activities.
When your patient is a smartphone user or a student who types, raise the bar. Cell phone use requires 148 degrees of flexion and a 107-degree pronosupination arc. Keyboard use demands 65 degrees of pronation. Stopping at the Morrey arc will leave these patients functionally limited for their most frequent daily tasks.
One important caveat from the authors: findings apply to typically developing children after trauma. For congenital conditions like proximal radioulnar synostosis, compensatory shoulder motion may allow function with far less elbow arc. Do not apply these thresholds rigidly to congenital deformity.