Pelvic Tilt Angle
Estimate sagittal tilt from PSIS-above-ASIS rise and horizontal landmark separation.
Description
Sagittal pelvic tilt follows the rise between PSIS and ASIS landmarks over their horizontal separation.
Sagittal pelvic tilt follows the rise between PSIS and ASIS landmarks over their horizontal separation. Signed rise fixes the anterior/posterior convention.1
Estimate sagittal tilt from PSIS-above-ASIS rise and horizontal landmark separation.
When to use Pelvic Tilt Angle
Use this tool to estimate sagittal tilt from PSIS-above-ASIS rise and horizontal landmark separation.
Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.
How to use Pelvic Tilt Angle and understand its results
- Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.
- Enter psisAboveAsisCm, horizontalSeparationCm, anteriorThresholdDegrees using the field table and calculation rules, then run the tool.
- Read tiltDegrees, anteriorTiltFlag. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| psisAboveAsisCm | Psis above asis cm | number | Required |
| horizontalSeparationCm | Horizontal separation cm | number | Required |
| anteriorThresholdDegrees | Anterior threshold degrees | number | Required |
Enter finite signed rise, positive span cm and nonnegative anterior threshold degrees. Return degrees and strict above-threshold flag.
angle=atan2(PSISaboveASIS,horizontalSpan) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| tiltDegrees | Tilt degrees | number |
| anteriorTiltFlag | Anterior tilt flag | boolean |
{
"input": {
"psisAboveAsisCm": 1,
"horizontalSeparationCm": 1,
"anteriorThresholdDegrees": 10
},
"output": {
"tiltDegrees": 45,
"anteriorTiltFlag": true
}
}Limitations and assumptions
No landmark identification, imaging or postural diagnosis is performed.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.
Alternative or Complementary methods
Use Craniovertebral Angle Screen: Calculate craniovertebral angle from C7-to-ear coordinates and compare with target. For a complementary task, use Thomas Hip Flexion Screen: Screen Thomas-test thigh rise while checking sufficient knee flexion.
References
-
Pelvic Tilt Angle — tool.io
Similar or alternative tools
- Craniovertebral Angle Screen
Calculate craniovertebral angle from C7-to-ear coordinates and compare with target.
- Thomas Hip Flexion Screen
Screen Thomas-test thigh rise while checking sufficient knee flexion.