Final answer:
Arthrotomy is the medical term that describes the surgical formation of a temporary opening in a joint for drainage purposes.
Step-by-step explanation:
The term that describes the surgical formation of a temporary opening in a joint for drainage purposes is arthrotomy. This procedure is done to alleviate fluid buildup or infection in the joint. During arthrotomy, a small incision is made in the joint capsule or synovium to allow for drainage and relieve pressure.
For example, if a joint becomes infected, such as the knee joint, arthrotomy can be performed to drain the infected fluid and prevent further complications. The incision is made in a way that allows for proper drainage while minimizing damage to the surrounding structures.