Читать книгу The Little Book of Medical Breakthroughs - Dr. Naomi Craft - Страница 7

For as long as people have been losing limbs there have been attempts to make artificial ones. A prosthesis is a replacement for a limb (or part of a limb) that has been amputated or may have been missing from birth.

The first known description of a prosthetic limb is in the Rig-Veda, an ancient Indian sacred poem written in Sanskrit between 3500 and 1800 BC. The story is about a warrior, Queen Vishpla, who lost her leg in battle. Once she had been fitted with an iron prosthesis, she was able to return to the fight.

Probably the oldest actual example of a prosthesis is the Cairo toe. It was found attached to the foot of an ancient Egyptian mummy dating from between 1069–664 BC. It is made of leather and wood, and is flexible. It looks worn, suggesting it was used, and not just added after death. Scientists believe the woman was in her mid-50s and may have lost the big toe from complications of diabetes.

Older still is the Greville Chester Great Toe, named after the man who acquired it for the British Museum, which dates between 1295 and 664 It is made of linen glue and plaster blended together, but this one doesn’t bend and was probably cosmetic.

Before the Egyptian toes were discovered, the oldest prosthesis in existence was the Roman Capua Leg, which was found in a grave in Capua, Italy, dating to 300 BC. It was made of bronze, but unfortunately it was destroyed during an air raid in the Second World War. A copy is kept at the Science Museum in London.

Generally, early prostheses didn’t have much function. Pliny the Elder (23–79 AD), a 1st-century Roman scholar, described a typical prosthesis when he wrote about Marcus Sergius, a Roman general who had his right hand amputated in the battle against Carthage (C. 218–201 BC). To allow him to get back to battle, Pliny writes that the general had an iron hand made by his armourer just to hold his shield in place. Others describe artificial legs that fitted into the stirrups allowing a soldier to balance on a horse, but not enabling them to walk.

In the 16th century, French Surgeon Ambrose Paré (1510–1590) started developing prosthetic limbs with basic functionality. ‘Le Petit Lorrain’ was a hand operated by springs and catches for a French army captain. He also invented an above-knee prosthesis, which consisted of a peg leg with a foot prosthesis. It had an adjustable system for attaching it to the body, knee-lock control and other engineering features.

By the 19th century, there had been more advances and greater attempts to make limbs more functional. For example, Douglas Bly of Rochester, New York, invented and patented ‘Doctor Bly’s anatomical leg’ in 1858. As Bly commented, this one still had its limitations:

‘Though the perfection of my anatomical leg is truly wonderful, I do not want every awkward, bigfatted or gamble-shanked person who always strided or shuffled along in a slouching manner with both his natural legs to think that one of these must necessarily transform him or his movements into specimens of symmetry, neatness and beauty as if by magic – as Cinderella’s frogs were turned into sprightly coachmen.’

A copy of an artificial leg in brass and plaster made around 1910 from the original at the Royal College of Surgeons, London. The original was found in a Roman grave in Capua, Italy.

In recent years, there has been more emphasis on developing artificial limbs that look and move more like actual human limbs. Advances in biomechanics, engineering and plastics, combined with the use of computer-aided design and computer-aided manufacturing, have all contributed to the development of more realistic artificial limbs.

One of the latest inventions in this field includes the world’s first commercially available bionic hand, which has five individually powered digits. To work it relies on the electrical signal generated by muscles in the remaining part of the patient’s limb to open and close the fingers. Electrodes sitting on the surface of the skin pick up the signals.

One of the first patients to be fitted with the bionic hand summarized the significance of the development when he said:

‘It’s truly incredible to see the fingers moving and gripping around objects that I haven’t been able to pick up before. The hand does feel like a real replacement for my missing hand.’