Splint

A splint is a device that immobilizes part of an individual's body - usually the spine or a limb - to promote healing or provide extra support.

Travis Mayweather was fitted with a splint while injuring himself during shore leave on Risa. 

By the 23rd century splints had largely been replaced by bone-knitting lasers and similar devices. 

In the 24th century the bone knitters on board the USS Enterprise (NCC-1701-D) stopped working due to an Iconian computer program running wild through the ship's systems. Doctor Katherine Pulaski ordered her staff to use splints on crew members with broken bones until the ship's systems could be repaired.