A forgotten collection of historical documents and artefacts telling the story of wounded soldiers in the First World War has been uncovered in a locked room and under floorboards at Erskine Hospital.

The extraordinary archive was discovered by staff researching the history of the hospital in Renfrewshire ahead of its centenary next year.

The collection includes lost records of soldiers, some in their teens, who were sent to the hospital after losing limbs in the Great War. There are also woodworking tools used by some of the recovering soldiers as part of their rehabilitation and a wide range of medical appliances, including a prosthetic limb designed and pioneered by Sir William Mcewan, co-founder of the hospital.

The archive will now be collated and preserved by Erskine, which cares for veterans of the armed forces, and Glasgow University's Archive Services led by the historian and television presenter Dr Tony Pollard.

Speaking at Glasgow University's archives in Thurso Street, where the collection is being preserved, Dr Pollard said he hoped the rediscovered archive would help shed new light on the medical developments during the Great War as well as raise the profile of Sir William and his pioneering therapeutic work with injured soldiers.

Dr Pollard, senior lecturer in History and Battlefield Archaeology at the University, said: "What we are unearthing at Erskine is quite remarkable. There are boxes upon boxes of wartime history which will shine a light on so many personal stories of bravery and endurance during the First World War, but also the incredible advancement in the treatment of injured personnel not just physically but mentally since 1916."

Before the establishment of the Princess Louise Scottish Hospital for Sailors and Soldiers, which became Erskine, wounded soldiers were sent to England to have an artificial limb fitted. Sir William then took up the challenge to establish a facility near Glasgow similar to Craiglockhart Hospital in Edinburgh, which treated shellshock and was made famous by the war poets such as Wilfred Owen.

"Sir William took up the challenge to establish the facility but what he did that was revolutionary was turn it into a therapeutic centre as well," said Dr Pollard.

"What we're seeing here is technology married to medical advances. Sir William got in touch with the shipyards on the Clyde and said 'can you work with us?' which they did. This is the point when they become the artificial limbs that we recognise today."

The archive collection will now be stored and preserved at the University Archives, and Erskine are working on a patient database of every soldier admitted and discharged at the hospital during its history which will be a valuable research resource for families tracing their relatives' history.

Sadly, only one example of the prosthetic leg Sir William designed is known to exist (it is in the British Museum) but Dr Pollard and the team hope that the publicity around the centenary will help uncover another. The archivists and historians at Glasgow University are convinced more examples of the so-called Erskine Leg could be out there and are appealing to members of the public to help find them.

Steve Conway, chief executive of The Erskine, said preparations for the centenary of the charity had made him realise that its archive had been largely neglected.

"Archiving records and preserving artefacts was never high on the priority list until we started to prepare for our centenary," he said.

"The partnership with Glasgow University and funding from The Wellcome Trust will enable us to restore, archive and digitise material which will be accessible to everyone. Hopefully these records and artefacts will help people to research family histories and also support research in to the care of veterans with physical or mental injuries sustained in the service of their country."

Dr Pollard also hopes the archive will provide more information on the extraordinary medical advances that were made during the First World War.

"This archive will not only chart the hospital's history but also provide an insight into the many medical developments over the last century, methods which helped change care practices towards casualties of war around the globe," he said.

"I am quite certain once we really start to delve into the vast collection, the findings will be used in research for many years to come."