Two years after the accident, he made the difficult decision to have his severely injured left leg amputated below the knee and replaced with a prosthesis made of carbon fiber and steel.

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The device, called the Argus II Retinal Prosthesis System and made by Second Sight Medical Products of Sylmar, Calif.

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And the conclusion was that the prosthesis amounted to technical aids for Pistorius and that made him ineligible to try to qualify for the Olympics.

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