rules_by_age.json

{
  "description": "Biomechanical gait analysis benchmarks and red flags by age group. Reference: Trupti Didi Clinical Benchmarks.",
  "age_groups": [
    {
      "range": "1-2",
      "name": "Early Toddlers",
      "benchmarks": {
        "heel_strike": "Not expected",
        "cadence_bpm": "150-180",
        "swing_knee_flexion": "45-55°",
        "stance_knee_angle": "> 150°",
        "asymmetry_threshold_percent": 15,
        "trunk_sway_threshold": 25
      },
      "clinical_notes": "Wide base of support and high-guard arm position are normal at this stage."
    },
    {
      "range": "3-4",
      "name": "Preschoolers",
      "benchmarks": {
        "heel_strike": "Inconsistent/Emerging",
        "cadence_bpm": "130-150",
        "swing_knee_flexion": "55-60°",
        "stance_knee_angle": "> 160°",
        "asymmetry_threshold_percent": 10,
        "trunk_sway_threshold": 20
      },
      "clinical_notes": "Heel strike should start becoming consistent. Persistent knee flexion in stance (>20deg) after age 3 is a red flag."
    },
    {
      "range": "5-7",
      "name": "Early School Age",
      "benchmarks": {
        "heel_strike": "Expected/Consistent",
        "cadence_bpm": "110-130",
        "swing_knee_flexion": "60-65°",
        "stance_knee_angle": "> 170°",
        "asymmetry_threshold_percent": 8,
        "trunk_sway_threshold": 15
      },
      "clinical_notes": "Gait pattern should be well-established and similar to adult morphology."
    },
    {
      "range": "8+",
      "name": "Mature/Adult",
      "benchmarks": {
        "heel_strike": "Mandatory",
        "cadence_bpm": "90-120",
        "swing_knee_flexion": "60-70°",
        "stance_knee_angle": "> 175°",
        "asymmetry_threshold_percent": 8,
        "trunk_sway_threshold": 12
      },
      "clinical_notes": "Adult-like symmetry and stability expected. High trunk sway or lack of heel strike indicates pathology."
    }
  ],
  "global_red_flags": [
    {
      "type": "Asymmetrical Loading",
      "description": "Significant difference between left and right limb metrics.",
      "severity": "moderate"
    },
    {
      "type": "Instability",
      "description": "High trunk sway or variable stride patterns.",
      "severity": "high"
    },
    {
      "type": "Developmental Delay",
      "description": "Gait markers significantly below age-group benchmarks.",
      "severity": "moderate"
    }
  ],
  "parameter_thresholds": {
    "step_length_symmetry": {
      "typical": 7,
      "mild": 12,
      "consistent": 15
    },
    "stance_time_symmetry": {
      "typical": 5,
      "load_avoidance": 8
    },
    "swing_time_symmetry": {
      "typical": 5,
      "control_related": 8
    },
    "stride_consistency": "High SD indicates instability/immature control"
  },
  "primitive_reflex_influence": {
    "moro": "Difficulty releasing support",
    "fear_paralysis": "Freezing",
    "tlr": "Extensor posture",
    "atnr": "Trunk rotation",
    "palmar": "Fisted hands"
  },
  "safety_rules": {
    "min_steps": 5,
    "min_duration_seconds": 3,
    "requires_independent_walking": true,
    "limitation_note": "Numerical interpretation limited due to context."
  }
}