The 29-year-old kicker missed two extra points and a 42-yard field goal in a 25-17 win over the Seattle Seahawks on Sunday, pushing all three kicks wide left.
Michael Badgley was signed from the practice squad to the active roster.
Sturgis made 9 of 13 field goal attempts and 9 of 15 PATs in six games this season.
Health had been a concern for Sturgis going into the 2018 season — he missed all but one game for the Philadelphia Eagles last year, spending most of 2017 on the injured reserve with a hip issue.
For the Chargers, Sturgis missed two games with a strained quad. In those games, Badgley replaced him and made all three of his field goal attempts, including a long of 44 yards, and all seven of his extra point attempts in wins over the Cleveland Browns and the Tennessee Titans.
The Chargers waived Badgley last week when Sturgis was deemed healthy enough to play. However, the Chargers brought Badgley back on the practice squad once he cleared waivers.