Standing Trunk Flexion and Extension Assessment
Introduction
The Standing Trunk Flexion and Extension Assessment evaluates your ability to bend forward and backward while keeping your knees straight. It provides valuable insight into spinal and hip mobility, flexibility, and movement control.
Purpose and Functionality
This assessment measures flexibility, control, and balance across the spine, hips, and legs. Proper trunk mobility allows for efficient movement, posture, and injury prevention during both daily and athletic activities. Restrictions or compensations in these motions can reveal tightness, muscular imbalances, or limited range of motion that impact performance and overall movement health.
What It Evaluates
Trunk Flexion: Measures how far you can bend forward from a standing position, reflecting flexibility in your posterior chain, including hips and spine.
Trunk Extension: Evaluates your ability to lean backward while standing, highlighting anterior chain flexibility and spinal/hip control.
Knee Flexion: Monitors how straight your legs remain during trunk movement. Excessive knee bending can indicate compensation or limited flexibility in the posterior chain.
Trunk Flexion Component
Trunk flexion measures how far you can bend forward from a standing position. This motion reflects the flexibility of your posterior chain—particularly the hips and spine—and helps assess how well your body maintains alignment during forward bending movements.
It is measured by the forward angle formed between your torso and lower body using landmarks such as the shoulders, hips, and knees. Flexion greater than 90° scores 100%, less than 45° scores 0%, and intermediate values are scaled linearly.
Scoring:
Trunk Extension Component
Trunk extension measures how far you can lean backward while standing. This movement evaluates anterior chain flexibility and the coordination between your spine and hips. It is particularly useful for identifying limitations in back extension that may affect posture or performance.
It is measured by the backward displacement of the shoulders relative to the hips. Extension greater than 30° scores 100%, less than 10° scores 0%, and values in between are scored linearly.
Scoring:
Knee Flexion Component
Knee flexion monitors how much your knees bend during trunk flexion or extension. Excessive knee movement can indicate compensatory patterns due to restricted hip or spinal mobility. Maintaining straighter legs demonstrates better posterior chain flexibility and control.
It is measured by the bend in your knees during the forward and backward movements. Less than 10° flexion scores 100%, more than 30° scores 0%, and intermediate values are scaled linearly.
