Glasgow flanker Ryan Wilson has escaped suspension after being accused of grabbing the testicles of Northampton scrum-half Lee Dickson.

Scotland back-rower Wilson had a citing complaint against him dismissed by European officials in a disciplinary hearing in London.

Wilson, overlooked for Scotland's RBS 6 Nations campaign by head coach Vern Cotter, was cited for the alleged offence in Northampton's 19-15 European Champions Cup victory over Glasgow on Sunday.

The 26-year-old is now free to return to action for both club and country, if required, given he could yet feature in Scotland's Six Nations campaign despite missing initial selection.

Wilson pleaded not guilty to the offence, with independent judicial officer Simon Thomas effectively throwing out the case.

"As the judicial officer was not satisfied to the required standard that the act of foul play as alleged had been committed, the citing complaint was dismissed and Wilson is therefore free to play," read a statement from European Professional Club Rugby (EPCR).

Wilson could have faced a minimum 12-week ban had he been found guilty of the offence, but is now free to return to action without delay.

But Glasgow team-mate and Scotland lock Tim Swinson was handed a one-week ban for punching Northampton hooker Mikey Haywood in Sunday's clash.

Swinson was sin-binned for the incident, and pleaded guilty to the offence in Wednesday's disciplinary hearing in London.

He is free to play from Monday, January 25, allowing the 28-year-old to take full part in Scotland's Six Nations campaign.

Meanwhile, Glasgow centre Richie Vernon has undergone shoulder surgery and faces a battle to return to action before the end of the season.

The Scotland international was omitted from the RBS 6 Nations squad because of the injury, which he suffered in a European Champions Cup defeat by Northampton on November 21.

Head coach Gregor Townsend said: "We're disappointed to lose Richie for the next few months.

"He failed to progress as expected, so in the end an operation was required, which will keep him out for most of the season. We wish him all the best with his recovery."

There was better news for Townsend after Rob Harley returned to training following a thumb injury while Peter Horne is close to a comeback following a foot problem.