In a landmark paper published in 1973, the eminent hand surgeon J. William Littler, MD, proposed two mathematical relationships between the anatomic and functional geometry of the hand. His proposal that the motion of the tips of the fingers follow an equiangular spiral has been experimentally supported. Studies have not supported his other idea that the lengths of the phalanges follow a Fibonacci series. This review, after providing the necessary mathematical background, reexamines Littler's claims, presents the associated studies, and re-evaluates their conclusions. Our analysis shows that the functional lengths of the phalanges of the little finger actually do follow a Fibonacci series and that the functional lengths of the index, long, and ring fingers follow a mathematical relative of the Fibonacci series.
Keywords: Fibonacci; Golden ratio; Hand; Littler; Mathematics; Phalanges.