Well, thanks to a high profile knife attack, the UK has now added a small set of provisions to the Criminal Justice Act.
http://www.bbc.co.uk/news/uk-37080682
Sub-Paragraph (r) being the legislation that restricted sale of "Samurai" Swords of course.2.—(1) The Schedule to the Criminal Justice Act 1988 (Offensive Weapons) Order 1988(1) (which specifies offensive weapons for the purposes of section 141 of the Criminal Justice Act 1988) is amended as follows.
(2) In paragraph 1, after sub-paragraph (r) insert—
“(s)the weapon sometimes known as a “zombie knife”, “zombie killer knife” or “zombie slayer knife”, being a blade with—
(i)a cutting edge;
(ii)a serrated edge; and
(iii)images or words (whether on the blade or handle) that suggest that it is to be used for the purpose of violence.”.
Having see how effective the last ban was, I'm sure this one will quell any troubles my fair country has been having with knife crime.