The strangest art story of the year grows stranger yet. Last October, Steve Wynn, the Las Vegas developer and art collector, accidentally shoved his elbow through Picasso’s Le Rêve (The Dream), the single most valuable work in his collection. Among the eyewitnesses were Barbara Walters and Nora Ephron, who amusingly detailed the mishap on her blog. In a bizarre coincidence, Wynn had agreed only the day before to sell Le Rêve to Steven Cohen, a hedge-fund tycoon, for $139 million. Now that deal is off and Wynn is suing Lloyd’s of London, the painting’s insurers, for its drop in value, which he puts at $58 million dollars. (He has blamed the accident on a medical condition that deprived him of his peripheral vision.)

In most accounts, the story has been played for laughs—the casino billionaire who is all elbows. The painting’s erotic subject matter has also drawn comment: it shows Marie-Thérèse Walther, the artist’s young mistress. It was painted in 1932, long after Picasso’s Cubist heyday, but some of its value can be ascribed to the light it casts on his personal life. Less has been said, however, about the peculiar sequence of events: one day the purchase agreement for the painting is signed, establishing its market value, and the next day the painting is mutilated before a large gathering of witnesses, instantly reducing its value and—in Wynn’s view—earning him a check for the difference.

Equally strange are the mechanics of the damage to the painting. An elbow thrust, however fierce or well-aimed, is not likely to puncture a linen canvas. Paintings are not stretched tight as a drum and have a certain degree of give, and the tendency of the fabric when struck by a blunt instrument is to dent or else to give way where it is nailed to the stretcher. In order to confirm this, I asked a painter friend to take a taut canvas and see if he could pierce it with his elbow. Working with heavy cotton duck canvas (a weaker fabric than the Belgian linen that Picasso likely used), he was only able to put a bowl-shaped depression into the canvas, despite repeated attempts.

The insurers will be investigating this case carefully. Perhaps they’ll ask to take a cast of Mr. Wynn’s elbow.