Protheses patents in and after World War I

One result of the tragic loss of limbs during World War I was a huge increase in the number of patents for protheses -- artificial limbs.

This can be tracked by using the free Espacenet database. Its classification schedules can be searched to identify A61F2 as the patent class for protheses. This can be used in the Advanced search as the CPC class and combined with e.g. publication years 1911-13 (expressed as 1911:1913) and with national country codes (GB, United Kingdom; US, United States; FR, France; and DE, Germany). It does rely on both coverage of patents during the period by indexers, and on accurate usage of the classes. It also includes applications made by foreign residents. As countries took different attitudes to assessing novelty other discrepancies turn up although they are not obvious. Some patents which are clearly not relevant are included as they were misclassified.

I analysed the publication years 1911-22 by those four countries and assembled the following table. As some applicants applied for patents in foreign countries there is some overlap. The numbers of patent documents are clickable links to get to the lists (which are in order of "priority", the original filing) and from them to the actual patents ("original documents").

	UK	USA	France	Germany
1911-13	8	61	4	0
1914-16	22	61	25	0
1917-19	195	115	154	9
1920-22	117	116	166	215

German patents were apparently not indexed by the CPC for much of our period, hence their absence for most of World War I.

The steep rise in patents clearly reflects concern, often by private inventors, about the subject. France and the UK had many more maimed soldiers than the USA, hence presumably the much bigger jumps in numbers.

It is also interesting how many Austrians and Germans were attempting to protect their inventions in foreign countries even during the war. The database's priority field can be used to ask for the original country, although it cannot be relied on. This is a list of the 22 German priority filings in the UK during 1911-1922, and of the 4 Austrian priority filings in the UK. Coded respectively as DE and AT. In theory as enemy aliens they would have been refused granted British patents. They do provide a translation of the concept, of course.

One thing we can't do, without a knowledge of the field, is to identify key patents. Similarly, only those familiar with the field can identify important inventors. Kim Norton's A brief history of prosthetics says that no major developments occurred in the field in World War I.

It also mentions Marcel Desoutter, a British aviator who lost a leg below the knee in a flying accident in 1913. Apparently he developed with the help of his brother Charles, an engineer, the first aluminium prothesis (this made it half the weight of a wooden leg). The database credits in our period Charles, alone, with three British patents, two of which were patented also in France and the USA. Here is the list. Desoutter continues to be an important British engineering company, mainly in tools. Below is one of the drawings.

Below is a drawing of an artificial hand from a patent by three Americans, US1380835.