逆エビ固め
One of the most well known spine cranks is the boston crab, which is usually depicted in pro-wrestling context. Similarly to neck cranks, spine cranks are illegal techniques in most combat sports, excluding some submission wrestling and mixed martial arts competitions, where they are used as submission holds. Even if allowed, spine cranks are very rarely featured because of the difficulty of applying them. Jonno Mears is the only man to have ever won a mixed martial arts bout with a Boston crab, which he achieved in 2017.