Sterilizable flexible surgical instrument system

A flexible surgical instrument, comprising:

• a distal structural body comprising at least one distal structural segment each comprising a distal fixing disk and distal structural backbones;
• a proximal structural body comprising at least one proximal structural segment each comprising a proximal fixing disk, proximal structural backbones, at least one first driving backbone, and at least one second driving backbone, the distal structural backbones being securely connected in one-to-one correspondence to or the same as corresponding proximal structural backbones;
• and
• a transmission unit comprising a transmission mechanism operable to convert a rotary motion into a linear motion,
• the transmission mechanism comprising:
• at least one steering backbone to transmit the linear motion, and the at least one steering backbone is operable to cooperatively push-pull the at least one first driving backbone and the at least one second driving backbone to turn the proximal structural segment;
• wherein a proximal end of the at least one first driving backbone and a proximal end of the at least one second driving backbone are securely connected to the proximal fixing disk;
• wherein a first end of the at least one steering backbone is connected to a distal end of the at least one first driving backbone, and a second end of the at least one steering backbone is connected to a distal end of the at least one second driving backbone.