A within-person randomised trial to investigate the effects of a rigid cervical collar on three-dimensional angular movement and angular acceleration during emergency spinal immobilisation and extrication procedures in elite football (soccer) players: The RESTRICT study

When a football player goes down with a suspected neck injury, the immediate priority for medical staff is to prevent any further damage to the spinal cord. The standard approach, used in emergency rooms and on sports fields alike, is to immobilize the entire spine. This usually involves placing a rigid plastic collar around the neck, strapping the player to a stiff board, and securing the head with blocks and tape. This combination is known as triple immobilisation. The logic is simple: if the neck cannot move, it cannot be hurt further. However, while this method is deeply ingrained in emergency care guidelines, the actual evidence supporting the rigid collar as a necessary component has been thin. Some experts worry that these collars might cause discomfort, leading conscious patients to shift their bodies in ways that could worsen an injury, or that they might simply be unnecessary if the rest of the immobilisation equipment is doing the heavy lifting.

A team of researchers set out to test this long-held assumption in the specific context of elite football. They wanted to know if adding a rigid collar actually stops the head from moving more than the strapping and boards alone, and whether it slows down the process of getting a player off the field. To find the answer, they did not wait for a real injury to occur. Instead, they recruited fifteen healthy, non-injured professional football players from a top English club. These volunteers acted as the injured players, undergoing a simulated rescue procedure where they were carefully rolled, lifted, and carried off a pitch. The researchers measured every tiny twist and turn of the players' heads relative to their chests, comparing two scenarios: one where the players wore the standard rigid collar, and another where they did not.

The study, known as the RESTRICT trial, followed a precise sequence of movements designed to mimic a real-life emergency. The players were first tilted to the left and right to allow a split stretcher to slide underneath them. Then, they were lifted into a basket stretcher, walked ten meters, and tilted again to simulate clearing an airway. Throughout this entire process, sensors attached to the players' heads and chests recorded exactly how much their heads moved and how quickly they accelerated. The goal was to see if the collar made a measurable difference in keeping the neck still.

The results revealed a surprising nuance. When the researchers looked at the total amount of movement over the entire procedure, the collar did not stop the head from moving significantly more than the no-collar condition. In fact, for most of the specific movements tested, the difference was so small it was barely noticeable. The only area where the collar showed a clear, measurable benefit was in limiting the total amount the head rotated, or turned side-to-side, during the entire sequence. Even then, the reduction was modest. During the specific task of tilting the player fifteen degrees to the right to insert the stretcher, the collar did reduce the side-to-side bending and the forward-and-backward bending slightly, but these differences were measured in mere degrees.

Perhaps more striking was the finding regarding speed. The researchers measured angular acceleration, which is essentially how quickly the head starts to move or stops moving. In almost every instance, the collar did not significantly change the speed of these movements. The only exception was during the lifting and lowering phase, where the collar slightly reduced the peak speed of movement, but the difference was so small that it is unlikely to have any real-world impact on preventing injury. The data suggests that once a player is strapped down with head blocks and body straps on a stretcher, the rigid collar adds very little extra protection against movement.

There was, however, a clear cost to wearing the collar. The entire procedure took significantly longer when the rigid collar was applied. The team recorded that the process took an average of 257.5 seconds with the collar, compared to 230.9 seconds without it. That is a difference of nearly half a minute. In a time-critical emergency where a player might be suffering from a rapidly developing head injury, that extra time could be meaningful. The study authors noted that while the collar is often used to provide a visual cue to practitioners to handle the patient with care, and to give conscious patients a sense of stability, it does not appear to be the primary factor in keeping the neck still during the complex process of extrication.

The researchers concluded that for the specific technique used in English football, which involves tilting the player to slide a stretcher underneath, the rigid collar offers no major advantage in restricting movement compared to the other immobilisation methods. The differences observed were statistically detectable but clinically negligible, meaning they are too small to matter in a real injury scenario. The study does not claim that collars are useless in all situations, nor does it suggest that medical staff should stop using them entirely. Instead, it highlights that the current practice of always applying a collar might be more about tradition than proven necessity. The findings suggest that in time-sensitive situations, or when the player is already securely strapped down, the collar might be loosened or omitted to speed up the rescue without compromising safety. This research provides a rare, data-driven look at a routine medical practice, challenging the medical community to reconsider whether every step of the standard protocol is truly required.