# 06 - 6A04 Developmental motor coordination disorde # 6A04 Developmental motor coordination disorder 139 Neurodevelopmental disorders Developmental motor coordination disorder Essential (required) features • Significant delay in the acquisition of gross or fine motor skills and impairment in the execution of coordinated motor skills manifesting as clumsiness, slowness or inaccuracy of motor performance is required for diagnosis. • Coordinated motor skills are markedly below those expected on the basis of age. • Onset of coordinated motor skill difficulties occurs during the developmental period, and is typically apparent from early childhood. • Coordinated motor skills difficulties cause significant and persistent limitations in activities of daily living, schoolwork, vocation and leisure activities, or other important areas of functioning. • Difficulties with coordinated motor skills are not better accounted for by a disease of the nervous system, disease of the musculoskeletal system or connective tissue, sensory impairment or a disorder of intellectual development. Additional clinical features • Young children with developmental motor coordination disorder may be delayed in achieving motor milestones (e.g. sitting, crawling, walking), although many achieve typical early motor milestones. Acquisition of skills such as negotiating stairs, pedalling, buttoning shirts, completing puzzles, tying shoes and using zippers may be delayed or pose difficulties. Even when a given skill is achieved, movement execution may appear awkward, slow or less precise than that of peers. Children may drop things, stumble, bump into obstacles or fall more frequently than peers. • Developmental motor coordination disorder may affect primarily gross motor functioning, primarily fine motor functioning or both aspects of motor functioning. • Manifestations of developmental motor coordination disorder typically persist into adult life. Older children and adults with developmental motor coordination disorder may be slow or inaccurate in a variety of activities requiring fine or gross motor skills, such as team sports (especially ball sports), bicycling, handwriting, assembling models or other objects, or drawing maps. • Other neurodevelopmental disorders commonly co-occur with developmental motor coordination disorder. In addition to disorders of intellectual development, attention deficit hyperactivity disorder and autism spectrum disorder, this also includes developmental speech sound disorder (particularly difficulties with articulation), developmental language disorder and developmental learning disorder. Although the presence of other neurodevelopmental disorders does not preclude the diagnosis of developmental motor coordination disorder, these disorders may also interfere with the execution of activities 6A04 Neurodevelopmental disorders | Developmental motor coordination disorder Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural or Neurodevelopmental Disorders of daily living, schoolwork, and vocational and leisure activities that require coordinated motor skills. Co-occurrence therefore complicates assessment and requires clinical judgement in attributing limitations in activities that require coordinated motor skills to a specific diagnosis. Boundary with normality (threshold) • There is considerable variation in the age of acquisition of many motor skills and a lack of stability of measurement in early childhood. Onset of developmental motor coordination disorder typically occurs during the early developmental period, but differentiation from typical development before the age of 4 years is difficult due to the variability in motor development and skill acquisition throughout early childhood. Therefore, the diagnosis of developmental motor coordination disorder is usually not made before the age of 5 years. • Performance of motor skills should ideally be assessed using appropriately normed, individually administered, culturally appropriate standardized tests of gross and fine motor coordination, and should include evaluation of the impact of symptoms at home and at school (or, in adults, in the workplace). Key features for assessment are persistence of motor skill impairment over time, severity of impairment and pervasiveness of impact on functioning. • Developmental motor coordination disorder often co-occurs with other neurodevelopmental disorders. Attention deficit hyperactivity disorder is most common (an estimated 50% of cases). Developmental speech and language disorder, developmental learning disorder (most often with impairments in reading and written expression) and autism spectrum disorder also commonly co-occur with developmental motor coordination disorder. Course features • Though there may be improvement in symptoms over time, with some children experiencing a complete remission of symptoms, the course of developmental motor coordination disorder is typically chronic, persisting into adolescence and adulthood in up to 50–70% of cases. The persistence of developmental motor coordination disorder into adulthood often affects social and psychological functioning as well as physical health. • The presence of other co-occurring neurodevelopmental disorders, such as attention deficit hyperactivity disorder, may further complicate the course of developmental motor coordination disorder. Individuals with co-occurring disorders typically experience more impairment than individuals with a single diagnosis. Neurodevelopmental disorders | Developmental motor coordination disorder 141 Neurodevelopmental disorders Developmental presentations • The prevalence of developmental motor coordination disorder is approximately 5–6% of children aged 5–11 years, although up to 10% of children may have less severe difficulties with motor skills that still affect academic and social functioning. • The manifestation of developmental motor coordination disorder symptoms varies with developmental stage. Preschool In preschool-aged children, delays in meeting one or more motor milestones (e.g. sitting, crawling, walking) or in developing specific skills (e.g. climbing stairs, buttoning clothing, tying shoes) may be evident. Middle childhood In middle childhood, symptoms may be evident in activities such as handwriting, playing with a ball, or building puzzles or models. Adolescence and adulthood By adolescence and adulthood, difficulties in motor coordination may manifest in attempts to master new skills, such as driving, using tools or note taking. All developmental stages Across all developmental stages, even once a skill is acquired, the execution of movements tends to be more awkward and less precise than in typically developing peers. • Children with developmental motor coordination disorder may also be at increased risk of co-occurring disruptive behaviour problems, anxiety and depression. In addition, children with developmental motor coordination disorder tend to report lower levels of self-efficacy and competence in physical and social abilities, and are at heightened risk of becoming overweight or obese compared to their typically developing peers. Sex- and/or gender-related features • Developmental motor coordination disorder more frequently affects boys, with a ratio of boys to girls of between 2:1 and 7:1. Boundaries with other disorders and conditions (differential diagnosis) Boundary with disorders of intellectual development Individuals with disorders of intellectual development may exhibit delays in acquisition and impairment in the execution of coordinated motor skills, along with deficits in general intellectual Neurodevelopmental disorders | Developmental motor coordination disorder