CMS

 Complex Motor Stereotypies (CMS) are repetitive, rhythmic, and involuntary movements that typically begin in early childhood. These movements are non-purposeful and often occur when a child is excited, engrossed, or stressed.

Common Examples

🖐️ Hand flapping
🙆‍♂️ Arm waving or posturing
🤲 Finger wiggling
🦵 Leg kicking or rocking
🙃 Head nodding or twisting

Key Features

• Usually emerge before age 3

• More common in neurotypical children, but also seen in ASD, ADHD, and intellectual disabilities

• Movements can be suppressed temporarily with effort

• Do not typically progress to other movement disorders

Causes & Mechanisms

🔬 Unclear, but theories include:

• Neurodevelopmental immaturity (altered basal ganglia/cortical circuits)

• Genetic predisposition (often runs in families)

• Sensory self-regulation (a way to manage emotions or stimuli)

Management

🩺 Reassurance – If CMS does not interfere with daily life, no treatment is needed
🧠 Behavioral Therapy – Habit reversal training or cognitive-behavioral strategies
💊 Medications (Rarely Needed) – Only considered if movements cause injury or significant impairment

Differential Diagnosis: CMS vs. Tics vs. Seizures

• Stereotypies → Early onset, rhythmic, triggered by excitement, voluntarily suppressible

• Tics → Sudden, brief, can change over time, often with premonitory urge

• Seizures → Involuntary, not suppressible, may have altered consciousness

CMS is usually a benign condition that improves with age, but tracking frequency and impact helps guide intervention! 🚀