Jan 24, 2018Cause of Clots
Over the past decade, at least 11 players in the NHL have been diagnosed with a blood clot of some type. Although the exact cause isn’t known, one reason may link with injuries and their travel schedule.
According to an article from Newsday, two types of blood clots are typically seen among athletes. The first is from thoracic outlet syndrome (TOS), where blood vessels are compressed in the space between the collarbone and first rib.
There are different types of TOS, but the venous TOS that has been seen in hockey players is relatively less common overall. With this, the vein under the collarbone is compressed — partly from genetics in conjunction with repetitive, over-the-head arm movement and muscle development.
“Maybe it’s a result of more stress placed on conditioning the upper body,” Karl Illig, MD, Professor of Surgery and Director of Vascular Surgery at the University of South Florida’s Medical Center, said. “I don’t think anybody really knows, but I would guess it’s time in the gym. Players have been playing hockey for a century without this happening.”
Another possibility could be the physical aspects of the game, along with the culture. Players commonly play while they’re hurt and have learned to do so since they were young.
“These hockey players are checking and constantly putting their shoulders [under stress],” Natasha Desai, MD, Assistant Professor of Sports Medicine at Columbia University Medical Center, said. “Who’s to say that’s not causing scar tissue leading to thoracic outlet?”
The second and more dangerous type of blood clot is deep vein thrombosis. This is usually caused by genetic factors but can be made worse by immobility after injury, which could help explain why hockey players are experiencing them.
“They travel a lot,” Desai said. “Any time there’s a vascular injury with a sedentary flow, that can initiate a blood clot – This would be for anybody, but think about the volume that these players get injured; then there’s surgeries and immobilization. [The rate of these factors] is probably higher than the general population.”
Players who have experienced TOS-related blood clots typically can expect to come back to the game, though they will need to be on blood thinners for a few weeks. During that period of time, it’s recommended to stay away from activity that could result in further injury.
“It’s not something to be taken lightly,” Laith Jazrawi, MD, Chief of Sports Medicine at NYU-Langone Medical Center, who also heads the Hockey Center at Langone, said. “[Someone on chronic blood thinners] may be hit in the head and get a concussion and bleed out.”
For cases with deep vein thrombosis, the most pressing risk is having the clot travel to the heart or lungs. Because of this, individuals with this type of blood clot must be cautious due to potentially fatal outcomes.
“When you get a lower-extremity clot [for example, in the leg], the obvious fear is that it will turn into a pulmonary embolism,” Jazrawi said. “[Even treatment] has risks and he may opt not to continue his career.”