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Activating the Omega 13

Time travel has long been a popular plot device among creators of fantasy and science fiction, from Mark Twain and H.G. Wells to modern screenwriters like Robert Zemeckis, James Cameron, and Rian Johnson. Contemporary treatments often center on alternate realities or ‘‘time lines’’ resulting from interference with the past. In films with more dystopic visions, such as Looper and The Terminator, unscrupulous forces intentionally violate the past in an effort to further their nefarious ends. In the more optimistic future imagined by Gene Roddenberry in the Star Trek universe, incursions into the past are usually unintentional, with the offending characters assiduously trying to avoid any action that might alter subsequent events. Galaxy Quest, director Dean Parisot’s affectionate 1999 parody of Star Trek, had its own quirky take on time travel. The film followed the misadventures of the former cast of the canceled television series Galaxy Quest, which had chronicled the intergalactic voyages of the fictional starship NSEA Protector. Hopelessly typecast, the unemployed actors are forced to scratch out a living making costumed personal appearances at fan conventions and appliance store openings. At one such event, they are approached by an apparent cadre of uniformed fans who are, in reality, a group of Thermian aliens from the Klatu Nebula. The aliens have intercepted the transmission of syndicated reruns of the television series, which they have mistaken for the historical archives of an advanced race. Facing extinction by a technologically superior species led by the ruthless General Roth’h’ar Sarris, the Thermians have meticulously reconstructed a fully functional replica of the Protector in an effort to defend themselves. Now, they urgently need the assistance of the original ‘‘crew’’ in order to operate it. When the actors realize that they have been beamed into outer space instead of onto an elaborate stage set, they are alternatively enthralled and terrified. The Thermians are particularly curious about the function of a mysterious device aboard the Protector, the Omega 13. Because the series was canceled just after the Omega 13 was added to the starship, the actors have no idea what it was meant to do. Sarris, who assumes the Omega 13 is a very powerful weapon, intends to destroy the Thermian ship and appropriate the device for his own use. Left with little choice, the actors endeavor to rise to the occasion and defeat Sarris. After many adventures and a climactic pitched battle, Sarris and his henchmen board the Protector and begin exterminating the crew. In desperation, the actor who played the captain of the Protector activates the Omega 13, which he has learned will either destroy the known universe or send it 13 seconds backwards in time. Fortunately, the latter of the 2 possibilities occurs, giving the crew just enough time to undo a crucial mistake and subdue the evil Sarris. In the world of time travel, 13 seconds ranks as a mighty short excursion, but it proves infinitely useful to the crew of the Protector. Consider what the invention of such a device would mean for sports medicine. Whenever a serious sports injury occurred, immediately activating the Omega 13 would furnish just enough time to alter the circumstances that led to the injury and avoid it altogether. Lacking such a boon, we must content ourselves with a much more laborious process of injury prevention. The procedure for devising and validating an injury prevention program was classically defined by van Mechelen and colleagues to require a progression of 4 steps. The first step is the performance of epidemiological studies to define the extent of the problem. This is followed by studies to identify the specific factors and mechanisms that lead to injuries. Once these are delineated, potential preventative measures are introduced, and finally, their efficacy is assessed by controlled repeat observation. A collection of articles in this issue of The American Journal of Sports Medicine (AJSM) exemplifies different parts of this progression, including the pitfalls of attempting to prevent sports injuries. In the first of these studies, Burger and colleagues pored over video footage from 3 renditions of the under18 Craven Week tournament to identify ‘‘Mechanisms and Factors Associated With Tackle-Related Injuries in South African Youth Rugby Union Players.’’ Citing evidence that more than half of youth rugby injuries occurred during a tackle, they focused on this aspect of the game. Using special software, the investigators compared 3 portions of the tackling sequence and the surrounding game situation between 49 documented injuries and 248 matched noninjury events. Their inspiration was the groundbreaking research of Torg et al that identified the spearing mechanism associated with catastrophic cervical spine injuries in American football. The authors faced a complex challenge, as they had identified 10 distinct tackle types from prior rugby research. Nevertheless, they were able to pinpoint several situational and mechanistic factors associated with a greater or lesser risk of injuries to both tacklers and ball carriers. The authors concluded that the next step towards making youth rugby safer would require the concerted efforts of medical and