Rush, from Humboldt, Sask., and brakeman Jesse Lumsden of Burlington, Ont., missed gold by just three-tenths of a second.
Spring was at the race just a week after a serious crash in Altenberg, Germany, sent the Calgary slider and two teammates to hospital.
"When I first saw Chris today at the track I got shivers," Rush said. "We got to speak together between heats. He is so beat up, but he is in such good spirits and was a real inspiration to us today, and that is no cliche."
The 27-year-old Spring needed to be airlifted from the track in Altenberg, Germany, because of the severity of his injuries, which included deep cuts, bruises and a broken nose.
Beat Hefti and brakeman Thomas Lamparter of Switzerland won the gold to take over the lead in the overall World Cup standings.
Manuel Machata of Germany posted his best season result by finishing third with brakeman Andreas Bredau.
Rush's medal was his seventh on the World Cup circuit and third in the two-man event. It was the first World Cup medal of Lumsden's career.
"Jesse pushed great today and it is nice to finally break through together," Rush said. "Second is good, but to be honest I like winning. We still have a lot of work to do to get us to the top of the podium."
The duo teamed up in the Canada 1 sled at the beginning of this season.
"I always felt like we had the tools, but just hadn't put it together," Rush said.
Canada's bobsled team pulled out of last week's World Cup in Altenberg citing safety concerns after the crash involving Spring, Saskatoon's Graeme Rinholm and Bill Thomas of Queensville, Ont. All three have been released from hospital.
"It was good to finally get back in a race," said Rush, who also crashed two weeks ago in Winterberg. "I always feel I'm only as good as my last race and that was a long time ago so it was nice to be back on the track and race well."
Previous overall World Cup leader Thomas Florschuetz of Germany is out for the season with a broken leg.
Hefti now has a 122-point lead over Maximilian Arndt of Germany. Arndt was sixth in the race.