Skip to main content

Overview

The SFMA back bend is a standardized movement assessment used in the Selective Functional Movement Assessment (SFMA) protocol to evaluate spinal extension and identify potential sources of pain or limitation. This assessment provides valuable information about thoracic and lumbar spine mobility.

Instructions

From a standing position, raise both arms forward and above you and reach upwards and behind you as far as possible. Allow your hips to come forward and your shoulders and head to move back. Hold max extended position for ~1 second then return to standing. Example image of a man doing an SFMA back bend

Dimensions

Required inputs for processing:
  • None

Movement Grading as Functional

Classification as “Functional” requires:
  • Shoulder flexion ROM ≥ 165°
  • Hips pass in front of toes
  • Shoulders pass behind heels
  • No shoulder compensation (a 10° reduction in shoulder flexion when nearing peak extension)

Discrete Metrics

MetricUnitsDescriptionColumn Name
Max Shoulder FlexiondegreesMaximum shoulder flexion angle (average of left & right)max_shoulder_flexion
Shoulder Flexion ROMdegreesRange of shoulder flexion motion (average of left & right)
Max Hip ExtensiondegreesMaximum hip extension angle (average of left & right)
Hips Pass ToesboolWhether hips move forward past toessfma_back_bend_hips_pass_toes
Shoulders Pass HeelsboolWhether shoulders move backward past heelssfma_back_bend_shoulders_pass_heels
Hips To Toes DistancemetersHorizontal distance from hips to toes at maximum reach. Positive value indicates reaching past mark, negative value indicates insufficient reach.
Shoulders To Heels DistancemetersHorizaontal distance from shoulders to heels at maximum reach. Positive value indicates reaching past mark, negative value indicates insufficient reach.
Shoulder CompensationboolWhether shoulder compensation occurred (> 10° reduction in shoulder flexion)sfma_back_bend_shoulder_compensation
FunctionalboolWhether movement is functional (see above)sfma_back_bend_functional

Notes

  • Kinematic data typically captured at 60Hz for stability activities