The Cavs said Varejao's operation was performed Friday at the Cleveland Clinic by Dr. Brian Donley, who was assisted by team physician Dr. Richard Parker. There is no timetable for his return.
Varejao injured himself Tuesday night in a win over Minnesota as he was battling for a rebound.
The Cavs lost their first game without Varejao in Miami, and his injury will likely accelerate the team's search to find inside help. Tristan Thompson took Varejao's spot in the starting lineup against the Heat.
Varejao has missed 166 games the past four seasons with injuries. Still, he was one of the team's best rebounders, which is why the Cavs signed him to a three-year, $30 million contract in October.