by Joseph C. Maroon, MD
Heindl Scholar in Neuroscience
Clincal Professor of Neurological Surgery
Team Neurosurgeon, Pittsburgh Steelers

Pittsburgh, November 15, 2007 -- Each year, there are approximately 10,000 cases of spinal cord injury in the United States, 10% of which occur during athletic events. Approximately 1.2 million high school athletes and 200,000 college and professional athletes participate in American football each year. Spinal injuries among professional football players are the most highly profiled. The range of spine injury can be as simple as a strain to complex fractures and cord injuries resulting in permanent injury and even paralysis.

Within this spectrum is a spinal cord injury referred to as neurapraxia. Neurapraxia is defined as transient posttraumatic paralysis of the motor and/or sensory tracts in the spinal cord. It has often been referred to as a “concussion of the spine,” however it can be a harbinger of a future potentially catastrophic injury in an athlete and can be a career-ending event in some cases.

Neurapraxia -- often referred to as “concussion of the spine” -- is usually caused by hyperflexion or extension when tackling and can potentially have catastrophic consequences.

The prevalence of neurapraxia is estimated to be seven per 10,000 football participants. Although not just a football injury it is usually is caused by hyperflexion or extension that can occur during tackling. Neurapraxia is most always associated with an underlying compromised or stenotic spinal canal. Stenosis may be due to degenerative disc disease with osteophyte formation, a herniated disc, congenital narrowing of the canal, or combinations of these elements. Symptoms are transient and are not associated with fracture dislocation or spinal instability.

Management of this condition is individualized and determined by the severity of symptoms, which usually involve transcend upper extremity numbness, and the underlying anatomical abnormality. In the April 2007 issue of Journal of Neurosurgery: Spine (6:356-363) we published a case study of five elite football players -- four of which were professional players in the prime of their career -- and presented their ultimate clinical management and outcome. All players required surgical intervention and all where able to return to playing football for an average of 2.5 years after surgery.

Underlying Spine Abnormality

The prevalence of congenital cervical stenosis in football players is reported to be between 7.6 and 29 cases per 100 players and therefore an inherent factor in these participants. Screening for stenosis can be done with MR imaging to assess the absolute spinal canal dimensions and to determine if there is compression of the spinal canal and cord from bone or disc causes. Loss of CSF around the cord is viewed by some as a possible risk for SCI.

Return to Play

Return-to-play decisions after an episode of neurapraxia and subsequent surgery are controversial. It is generally recommended that athletes with neurapraxia secondary to a herniated cervical disc, focal stenosis, or compressive osteophyte not be allowed to participate further in contact sports.

In our review of managing neurapraxia, a strong case is made for safe return to play following correction of the anatomical abnormality for single level disease. There has generally no consensus on this issue but most agree that two- or three-level cervical decompression and fusion is considered a relative contraindication for returning to play.

We demonstrated that in neurologically intact athletes, at the time of surgery, with focal cord compression due to a single-level herniated disc, they may safely return to football after successful surgical decompression and fusion. Interestingly in this series of five cases, two of the subjects required career-ending surgery for repeated herniation above and one below the previously fused level.

We are unaware of any permanent neurological deficit suffered by an athlete returning to play after he has undergone a single-level ACDF for neurapraxia but the decision to return to play must include a complete and through review of potential risks and complications and the full awareness and understanding of the patient.