> ## Documentation Index
> Fetch the complete documentation index at: https://docs.uplift.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# SFMA Shoulder Extension

> Biomechanical analysis of SFMA shoulder extension range of motion assessment, including compensations and functional scoring.

## Overview

The SFMA shoulder extension is a standardized movement assessment used in the Selective Functional Movement Assessment (SFMA) protocol to evaluate shoulder extension range of motion and identify potential sources of pain or limitation. This assessment provides valuable information about shoulder mobility and function.

## Instructions

Stand upright with arms at your sides. Reach the testing arm backward as far as possible, keeping the elbow straight and palm facing inward. Avoid rotating the trunk or tilting the pelvis. Hold briefly at maximum extension, then return to the starting position. Repeat on the opposite side.

## Example Videos

### Left

<Frame>
  <video controls src="https://uplift-docs-assets.s3.amazonaws.com/range_of_motion/range_of_motion-sfma_shoulder_extension-left_combined.mp4" />
</Frame>

### Right

<Frame>
  <video controls src="https://uplift-docs-assets.s3.amazonaws.com/range_of_motion/range_of_motion-sfma_shoulder_extension-right_combined.mp4" />
</Frame>

## Dimensions

Required inputs for processing:

* **Handedness:** the side \['left','right'] performing the movement

## Generic Outputs

Every capture includes session metadata, standard joint angle/velocity time series, and 3D keypoint positions common to all movements. See [Generic Outputs](/biomechanics/activities/generic_outputs) for the full list.

## Events

| Event           | Description                                     | Column Name |
| --------------- | ----------------------------------------------- | ----------- |
| MaxElbowFlexion | Frame of maximum elbow flexion during extension | \`\`        |

## Discrete Metrics

| Metric                  | Units   | Description                                     | Column Name                                            |
| ----------------------- | ------- | ----------------------------------------------- | ------------------------------------------------------ |
| MaxElbowFlexion         | Degrees | Maximum elbow flexion angle                     | \`\`                                                   |
| MaxExtensionAngle       | Degrees | Maximum shoulder extension angle                | `sfma_shoulder_extension_peak_extension_angle`         |
| MaxInternalRotation     | Degrees | Maximum internal rotation                       | `sfma_shoulder_extension_peak_internal_rotation_angle` |
| SideBendComp            | -       | Whether side bend compensation occurred (> 20°) | \`\`                                                   |
| WristDeviation          | Degrees | Wrist deviation angle                           | `sfma_shoulder_extension_wrist_deviation`              |
| Functional              | -       | Whether movement is functional                  | `sfma_shoulder_extension_functional`                   |
| WristToShoulderDistance | m       | Distance from wrist to shoulder                 | \`\`                                                   |

## Notes

* Maximum elbow flexion is detected using peak detection with inverted signal
* The event is used to identify the time point for assessing wrist/fingertip position relative to shoulder
* Functional movement is determined by wrist/fingertip position relative to shoulder