Edmund M. Kosmahl, PT, EdD



Note: Opposition of the thumb causes the pad of the thumb to face (oppose) the pads of the fingers. Opposition cannot be measured with a goniometer. The American Academy of Orthopaedic Surgeons suggests that opposition range is normal when the tip of the thumb can touch the base of the fifth finger. When range is not adequate, a ruler can be used to measure the distance between the tip of the thumb and the base of the fifth finger.

 Thumb CMC Opposition Photo

Test Position

  • Subject sitting with forearm supinated and resting on table
  • Wrist neutral
  • Stabilize fifth metacarpal

Normal Range

  • Able to touch tip of thumb to base of fifth finger (American Academy of Orthopaedic Surgeons)

Goniometer Alignment

  • Goniometer cannot be used
  • Use a ruler to measure distance between tip of thumb and base of fifth finger

Normal End Feel

  • Capsular or soft tissue approximation

copyright 1999 E. Kosmahl