It's the unglamorous reality of life in the NHL: Everyone plays hurt at some point, and it's rarely just one thing.
Diagnosing injuries is already a dense thicket when it comes to athletes who are conditioned to tolerate pain, and concussions add another thick layer of mystery and complexity.
Which brings us, circuitously, to Sidney Crosby.
The Pittsburgh Penguins' superstar, possibly the globe's most scrutinized concussion victim, has lately experienced similar symptoms due to a neck ailment, news that has prompted a sizable amount of confusion and consternation.
There has also been the occasional burst of superheated punditry aimed at the Pens' medical team because of conflicting reports over what's actually wrong (an injury, initially reported as healed fractures last weekend, is now officially a soft-tissue problem).
But the diagnosis rang familiar bells in a physiotherapy clinic in Laval, Que.
Maxime Gauthier, a sports therapist who specializes in treating cervical problems, said he's seen similar situations crop up among the NHL players he's treated, Simon Gagné of the Los Angeles Kings and Matthew Lombardi of the Toronto Maple Leafs chief among them.
Both Gagné and Lombardi have concussion histories, and both players also struggled with related neck issues, which sometimes were manifested in symptoms similar to some classical concussion indicators.
"If Matthew Lombardi can't go to a movie without throwing up in his popcorn, I can't do anything for him other than say 'go see a neurologist,'" Gauthier said. "But if a few weeks or months later, once the scans are clear, he comes to me and says he gets headaches or feels a tiny bit dizzy when he's swinging a golf club, for example, there might be something wrong with his neck."
In the case of Lombardi and Gagné, physiotherapy, massage and specialized techniques proved helpful in clearing up lingering headaches and other problems.
"It's a tricky area," Gauthier said. "You can have small tears to ligaments and muscles, bone bruises, nerves that can get impinged, and it's not always immediately obvious what symptom is related to what injury. You go by process of elimination, differential diagnosis, it's what doctors do, and sometimes it takes time to get to the bottom of everything."
That was true of Lombardi, who missed a year's worth of games with his second concussion. He also sustained a concussion in the spring of 2004 that kept him sidelined, although the 2004-05 season was lost to a lockout. The first concussion was quickly diagnosed as a neck issue because his head was snapped back from the hit but the second concussion was not immediately related to a neck problem.
This does not mean his doctors did not check for neck problems, just that it was difficult to sort out what was a neck problem and what was a true concussion symptom.
"It's pretty hard to differentiate them, especially at first," Lombardi said because his symptoms were different for both injuries. He said he had headaches like all concussion victims with his second concussion but he also had the feeling of his head being squeezed constantly.
"Then when I was exercising I'd feel like I was getting a fever and I was burning up," Lombardi said.
Over last summer, after he was traded from the Nashville Predators to the Maple Leafs, most of Lombardi's trouble was traced to his neck. By that time, he was seeing three specialists, two osteopaths and Gauthier. "That combination I felt was working right away," he said.
Lombardi said the one thing he learned is that every head injury is different. But the best thing to do is, like Crosby, see as many specialists as you can. Lombardi says he saw six specialists in treating his second concussion.
"I can't say this guy or that guy fixed me," he said. "Everybody chipped in and kind of got what I needed to get done.
"I think one of the important things with these injuries is you have to remain pro-active. You don't stay home and wait it out. Whatever you do, whether it's neck-work or osteopath work, get right in there right away. Hopefully you'll speed [the recovery]up."
The relationship between neck and head injuries may be new to many hockey fans, but it isn't to the medical community.
A pair of Ontario-based university researchers penned a study in 2006 that found "a strong association between whiplash-induced neck injuries and the symptoms of concussion in hockey injuries."
James Kissick, a concussion expert and former Ottawa Senators team doctor, said it's often the case when dealing with professional athletes that injuries are "multifactorial," and that includes brain trauma.
"Concussions can occur in a bunch of different ways," Kissick said. "Many of those mechanisms also involve the neck. As symptoms become more chronic, you start to think, okay, is there anything else here?"
Research shows that roughly 85 per cent of concussed brains return to normal cognitive function within seven to 10 days, but when it comes to the other 15 per cent, all bets are off.
Because symptoms can be exacerbated by factors like mood changes, sleep and fatigue, there is often a complex interplay at work.
"Sometimes it's all concussion, sometimes it's all neck, but more often it's both," Kissick said.
Working with concussed athletes, he continued, "[is]tough, it's real detective work."
With reports from Anne McIlroy and David Shoalts