Thom suffered the injury in a tackle on David Wallace, and though he carried on after some lengthy treatment on the pitch, the winger was in pain throughout.
Blunders cost Scotland dear in a match they led at half-time. Thom told The Times: “It is really disappointing, the first half we came out flying and did everything we said we were going to do, but the little individual mistakes in the second half really cost us. It is down to the players, we let ourselves down with little errors. We have to improve on that if we are to beat England,” he said.
“It did help them that they have the confidence of seeing out games after coming in on a winning streak. At one stage I firmly believed that we were going to do it but a few mistakes in the second half cost us. We have one more shot. The good thing about the Six Nations is that there is only a one-week turnaround and there are lot of upset guys in the changing room looking to make amends.”