The 6th-ranked Russian sustained the injury on Tuesday and said he was unlikely to be able to play in Paris next week.
"Even if the inflammation and pain pass, I will have no time for preparation,'' Davydenko said.
Davydenko said that if there was no pain by the end of the next week he would have two weeks to prepare for the season-ending Masters event in Shanghai.
Murray, fresh from winning the Madrid Masters on Sunday for his fourth title this season, broke Troicki in the fifth and eighth games of the first set. The fourth-ranked Briton had an early break in the second set and saved the only break point he faced in the eighth game.
"He (Troicki) made a lot of mistakes on his forehand today,'' Murray said. "I haven't seen him play so much, so I didn't really have too may tactics, but for my game I tried to serve well and change the speed of the ball a lot.''
It was the eighth consecutive win for the U.S. Open finalist, including two victories in Britain's Davis Cup World Group playoffs against Austria in September.
Murray, who also won titles in Doha, Marseille and Cincinnati, next plays Ernests Gulbis of Latvia.
Earlier, Fernando Verdasco beat wild card Karlis Lejnieks 6-1, 6-3 to reach the quarterfinals.
The third-seeded Verdasco had little trouble against the 20-year-old Latvian, the lowest-ranked player in the field at No. 664 and playing in his first ATP event. The 15th-ranked Spaniard, a runner-up to Murray here last year, had two breaks in each set to closeout the match in 65 minutes.
In the quarters, Verdasco will face German veteran Rainer Schuettler, who defeated Dominik Hrbaty of Slovakia 6-3, 6-3.
In other first-round action, Kazakhstan qualifier Andrey Golubev served 19 aces to beat Olivier Rochus of Belgium, 6-1, 6-4.
I Would Never Have Moved To Barcelona - Trezeguet
Defending champ Davydenko advances at Kremlin Cup
Andy Murray into Madrid Masters 3rd round
