Choking identified as potential contributor to cognitive damage in MMA

Last year a study was published discussing the risk of Vertebral Artery Dissection from chokeholds in combative sports. A more recent case study was published suggesting that in addition to this, repetitive chokes may, in fact, lead to brain injury for MMA athletes.

The recent case study canvassed a 40-year-old man who had been practicing MMA for a decade.  He developed memory problems and other cognitive dysfunction. Ultimately he was diagnosed with chronic traumatic encephalopathy (“CTE”). The authors opined that the CTE was likely caused from the repetitive concussive and sub-concussive blows the patient experienced in MMA noting that “Our patient exhibited symptoms of CTE secondary to repetitive sub-concussive brain trauma received from both training and competitions.”

Interestingly, however, the authors went on to note that some of the fighter’s dysfunction may be due to repetitive choking from MMA.  The following observations were published:

What is perhaps little discussed is the role of asphyxia in the contribution towards long-term behavior and memory changes in the MMA athlete over time. As mentioned, a neck choke is identified as the cause of match stoppage when a competitor submits or the referee stops the match, as the afflicted competitor appears to be syncopal or asphyxiating….In the course of an MMA athlete’s career, it is certain that they would receive such transient asphyxiation episodes multiple times from participation in matches, or even during training, given the fact that the neck choke is a commonly accepted move of offence. Neurological injury due to compression of the neck could potentially occur. In studies pertaining to suicidal hanging, a force of 2 kg was found to be sufficient to compress the jugular veins to the point of causing cerebral edema, followed by the carotid arteries with 5 kg of force, which might cause hypoxic brain injury. Compression of the airways needs a greater force of about 15 kg, which leads to severe hypoxia and death [28]. Doppler sonography reveals that it is possible to completely stop the blood flow of the carotid and vertebral arteries in a neck choke hold, which is characterized by pressure on lateral parts of the neck [29]. The issue of hypoxic ischemic brain injury (HI-BI) may develop in the long term in MMA athletes as they are subjected to frequent repeated transient asphyxiation and strangulation, leading to intermittent hypoxic events to the brain. Common mechanisms involved in the development of HI-BI include cardiopulmonary arrest, respiratory failure, and carbon monoxide poisoning. It is also known that about 30%–60% of patients who develop HI-BI as a result of cardiac arrest will develop persistent cognitive, behavioral, and neurological problems [30]. Impairment in attention, particularly vigilance and processing speed, together with memory problems have been observed in survivors with HI-BI. In addition, there are also reports of visual spatial dysfunction, apraxia, agnosia, and affective and personality changes in patients who had HI-BI [30]. In our patient, we performed repeated neuropsychological testing, which revealed decreased performance of his attention span and memory over time. There is a possibility that the patient could also have suffered some degree of HI-BI in addition to CTE, which reduced his overall cognitive abilities.

The full study is titled “Dangers of Mixed Martial Arts in the Development of Chronic Traumatic Encephalopathy” and can be found here Dangers of Mixed Martial Arts in the Development of CTE

Author Erik Magraken is a British Columbia litigation lawyer, combat sports law consultant, founder of the Combat Law Sports Blog, and profoundly appreciated UGer.