A drone placing Spock into a medical unit

A medical unit was part of the underground factory complex on the Shore Leave Planet, capable of repairing damage to biological organisms.

In 2269, a robot hovercraft was tricked into carrying Spock into the underground areas of the planet after Doctor McCoy injected him with melenex to make it appear that he was seriously injured. (TAS: "Once Upon a Planet")

This unidentified device was described in the script notes as a "clear plastic tube-like chamber." It is further noted that after Spock was placed into it, the robot "pushes a button and the curved-top of the tube slowly starts to close," before "Spock dives out of the cylinder...".
This technology was presumably that which repaired the impaled Dr. Leonard McCoy in "Shore Leave", as there was no indication that the planet's technology had changed, only that there was a change in who was running it.
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