Arms

Upper-extremity morphology: arm length, upper arm and forearm circumference, biceps definition, brachioradialis visibility, cubital alignment. Splits the original 'Limb' atlas category into separate arms.json + legs.json files for finer-grained morphology. Dimensions are drawn from sports-medicine and anthropometry literature.

Dimensions

• Arm length (proportional)

  partly photo-observable

  ordinal · arm_length_qualitative

  Total arm length (acromion to fingertip) relative to torso length.

  Aligned with anthropometry descriptors of upper-extremity proportional length relative to torso.

  Valid values (3)

  • shortShort— Arms appear short relative to torso.
  • balancedBalanced— Standard proportional arm length.
  • longLong— Arms appear long relative to torso.

• Upper arm circumference (relative)

  photo-observable

  ordinal · upper_arm_girth_qualitative

  Upper arm girth at mid-bicep, qualitative bucket.

  Aligned with anthropometry descriptors of mid-bicep circumference relative to forearm.

  Valid values (4)

  • slenderSlender
  • averageAverage
  • muscularMuscular
  • very_muscularVery muscular

• Biceps definition

  photo-observable

  ordinal · biceps_definition_qualitative

  Visible biceps definition (separation between biceps brachii and surrounding tissue).

  Aligned with sports-medicine descriptors of brachial musculature visibility.

  Valid values (4)

  • minimalMinimal— Biceps not visible as a discrete landmark.
  • moderateModerate— Biceps visible under tension only.
  • definedDefined— Biceps clearly visible at rest with separation from triceps.
  • highly_developedHighly developed— Pronounced biceps mass with peak definition.

• Forearm circumference (relative)

  photo-observable

  ordinal · forearm_girth_qualitative

  Forearm girth at maximum proximal circumference.

  Aligned with anthropometry descriptors of forearm girth.

  Valid values (4)

  • slenderSlender
  • averageAverage
  • muscularMuscular
  • very_muscularVery muscular

• Brachioradialis visibility

  partly photo-observable

  ordinal · brachioradialis_qualitative

  Visibility of the brachioradialis muscle as a distinct surface landmark on the lateral forearm.

  Surface-anatomy descriptor aligned with sports-medicine and aesthetic-anatomy literature.

  Valid values (3)

  • not_visibleNot visible
  • subtleSubtle— Visible under tension only.
  • definedDefined— Clearly visible at rest.

• Cubital (carrying) angle

  partly photo-observable

  categorical · carrying_angle_qualitative

  Angle between the upper arm and forearm at the elbow when the arm is extended and supinated. Sex-dimorphic and individually variable.

  Aligned with orthopedic descriptors of the elbow carrying angle. Reference: typical female ~10-15° valgus, male ~5-10° valgus.

  Valid values (4)

  • minimal_straightMinimal / straight— Arm extends nearly straight; carrying angle <5°.
  • normal_male_rangeMale-typical range (~5-10°)
  • normal_female_rangeFemale-typical range (~10-15°)
  • pronouncedPronounced (>15°)— Substantial valgus; cubitus valgus when extreme.

• Shoulder-to-arm proportion

  photo-observable

  categorical · shoulder_arm_proportion_qualitative

  Relative dominance of shoulder breadth versus arm girth — captures the V-shape silhouette differently from torso.json's shoulder_breadth dimension.

  Aligned with artistic-anatomy proportional descriptors.

  Valid values (3)

  • shoulder_dominantShoulder-dominant— Shoulders pronounced relative to arm girth.
  • balancedBalanced
  • arm_dominantArm-dominant— Arm girth pronounced relative to shoulder breadth.