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ing par ts Poorly perform y these db can be replace les. medical mirac
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Bionic
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dy pa o b
Artificial limbs
din g n gu o s a HAND—am
The first known prosthesis (artificial body part) was a wooden toe found on a 2,700-year-old Egyptian mummy. Since that time, artificial hands, feet, arms, and legs have all been made. Early ones were forged from metal or carved from wood. Some wooden hands (above) had hinged finger joints and could be locked in a gripping position to hold objects.
The ball of the prosthetic hip joint fits into the socket in the pelvis.
Hip j oint s
ca
n
b
er
.
The spiked end is fitted into a hole drilled in the femur (upper leg bone).
eplac ed to relieve arth riti s
Hearing aid
Early hearing aids were big funnels called ear trumPets that channelled sound waves from the air into the ear. Some were made from silver and decorated ornately, while others were hidden in walking sticks so users could be more discreet. Modern hearing aids use a microphone to pick up sounds and an electronic amplifier to make them louder, before they are replayed close to or inside the ear.
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