when a man spreads a woman's legs, pins them back and fucks her so hard her back cracks. This custom became so popular in the early 1980's that some enthusiasts would have spinal adjustment parties and couples would simultaneously engage in this form of boning. The combined sound of all the cracking spines gave the aural illusion of crickets chirping. The practice didn't quite reach "fad" status, though, as it really didn't sound that close to crickets chirping and it was only interesting to the bystander for a few quick moments. Eventually, the party idea died out and currently spinal adjustments are practiced in the privacy of one's home. This has been known to save dozens of dollars in chiropractor bills, cutting health costs by 0.00001%, though statistics have only been kept since Valentines Day, 2012.
Harold: Hey, Fred, what's with Steph?

Fred: Fucked her so hard last night, I gave her a spinal adjustment.
Harold: Oh, okay. That's awesome. The way she was walking, I thought she had some kind of pussy rash.
Fred: No, it was great. Had her up to five pops. Got four more on the last thrust. Adjusted!!! (high fives)
by theinstigator December 13, 2013
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