Iron hands are metal

prostheses In medicine, a prosthesis (: prostheses; from ), or a prosthetic implant, is an artificial device that replaces a missing body part, which may be lost through physical trauma, disease, or a condition present at birth (congenital disorder). Prosthe ...

for hands and upper extremities from the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to the late 15th centuries, similarly to the post-classical period of global history. It began with the fall of the Western Roman Empire and ...

and early modern period. These designs combined cosmetic and functional properties. The most famous example of an iron hand was made around the year 1530, being the second prosthetic hand made for the German knight

Götz von Berlichingen zu Hornberg (, ; 15 November 1480 – 23 July 1562), also known as Götz of the Iron Hand (German language, German: Eisenfaust), was a 16th-century Germany, German (Franconian) Imperial Knight (''Reichsritter''), mercenary and poet. He wa ...

.Quasigroch, Günter: ''Die Handprothesen des fränkischen Reichsritters Götz von Berlichingen. 2. Fortsetzung: Die Zweithand.'' In: ''Waffen- und Kostümkunde.'' Vol. 25, 1983, pp. 103–120. Most iron hands are based on the same constructive principles, although there are considerable differences in complexity.

Finger A finger is a prominent digit (anatomy), digit on the forelimbs of most tetrapod vertebrate animals, especially those with prehensile extremities (i.e. hands) such as humans and other primates. Most tetrapods have five digits (dactyly, pentadact ...

s can be flexed passively (for example using the healthy hand) and are locked in place by a

ratchet Ratchet may refer to: Devices * Ratchet (device), a mechanical device that allows movement in only one direction * Ratchet effect in sociology and economics * Ratchet, metonymic name for a socket wrench incorporating a ratcheting device * Ratc ...

mechanism, similar to those of contemporary flintlocks.

Extension Extension, extend or extended may refer to: Mathematics Logic or set theory * Axiom of extensionality * Extensible cardinal * Extension (model theory) * Extension (proof theory) * Extension (predicate logic), the set of tuples of values that ...

of the fingers works by

spring Spring(s) may refer to: Common uses * Spring (season), a season of the year * Spring (device), a mechanical device that stores energy * Spring (hydrology), a natural source of water * Spring (mathematics), a geometric surface in the shape of a he ...

pressure.

Bibliography

* Löffler, Liebhard: ''Der Ersatz für die obere Extremität: die Entwicklung von den ersten Zeugnissen bis heute.'' Stuttgart: Enke 1984, . * Putti, Vittorio: ''Historical Prostheses.'' In: '' Journal of Hand Surgery.'' Vol. 30, No. 3, Edinburgh: 2005, pp. 310–325.

References

Prosthetics History of mechanical engineering {{biomed-engineering-stub