A new recommendation by the NFL's Head, Neck, and Spine Committee and the Player Safety Advisory Panel will put some teams' plans to wear throwback uniforms in jeopardy.

ProFootballTalk.com obtained a league memo passed along to the clubs which discourages the teams from wearing different helmets as part of throwback uniforms.

"Our Head, Neck, and Spine Committee, chaired by Drs. Hunt Batjer and Richard Ellenbogen, and the Player Safety Advisory Panel, chaired by John Madden and Ronnie Lott, have recommended that players no longer wear different helmets as part of a 'Throwback' or 'Third' uniform,” the memo says. "Our office supports this change and has reviewed it with the chairman of our Health and Safety ownership committee, Dr. John York, who concurs with this recommendation."

So while teams can still wear throwback jerseys, they are strongly cautioned against new helmets. The first team affected by this change appears to be the Tampa Bay Buccaneers, who will scrap plans to wear their Bucco Bruce uniforms on Sept. 29 against the Arizona Cardinals.

"While we regret that our players will not be able to don the ‘Bucco Bruce’ helmet and traditional orange, red and white uniforms, there simply was no acceptable way to meet the requirements of the new policy while staying true to the spirit of our throwback theme," Buccaneers Chief Operating Officer Brian Ford said in a release. "We will continue to explore options with the league office for bringing back this fan favorite in future seasons.”

Both the Chicago Bears and the Buffalo Bills have worn throwback uniforms this year, but those helmets only required adding or removing logos from the teams' standard helmets. The Buccaneers' uniforms would require entirely new helmets.

Other teams that switch helmets for throwback uniforms include the Dallas Cowboys, Carolina Panthers and New England Patriots. It is not yet known if those clubs will also scrap their uniforms.