CORRELATION OF THE SENSORY LEVEL WITH THE ANATOMIC LEVEL OF THE LESION

R. Douglas Collins, Illustrated Manual of Neurologic Diagnosis, J. B. Lippincott Company, 1962

If the wrist is flexed the hand assumes the position of nonfunction (B) and if dorsiflexed the position of function (C). In either case the muscles are in balance. (A and D) Manikin of hinged blocks for bones and strings for tendons shows how the hand automatically assumes the position of nonfunction when wrist is flexed and the position of function when wrist is dorsiflexed.