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The Torg ratio and space available for the cord (SAC) have been applied in the literature to characterize spinal cervical canal dimensions; however, neither has been shown to be clinically practical secondary to low positive predictive values for neurologic symptoms. It is our hypothesis that taking the SAC and averaging it over cervical levels C3 through C6 will best characterize the geometric changes in the subaxial cervical spine and their relationship to the multidimensional pathogenesis of chronic stingers. Football players in heavy-contact positions, therefore, should have smaller mean subaxial cervical space available for the cord values (MSC-SAC) than those in light-contact positions. In this retrospective, case-controlled comparative study, magnetic resonance images (MRIs) of 77 athletes participating in the 2005 and 2006 National Football League Scouting Combine and a nonathlete control group of 42 male patients were reviewed. The SAC index was calculated using measurements taken in triplicate from midsagittal T2-weighted MRIs of the cervical spine and averaged for each subject over cervical levels C3 through C6, generating an MSC-SAC value. Heavy-contact athletes had significantly smaller MSC-SAC values compared to light-contact athletes (4.90 ± 0.02 mm [n=58] vs 5.90 ± 0.06 mm [n = 19], respectively). There was statistical difference between the mean SAC values of the heavy- and light-contact groups at each individual cervical level, C3 through C6. Compared to the control group (n=42), the light-contact group had significantly smaller mean SAC values only at the C3 level, whereas the heavy-contact group had significantly smaller mean SAC values at all levels, C3 through C6. In conclusion, heavy-contact athletes have smaller MSC-SAC values as compared to light-contact athletes, which may reflect the repetitive trauma to the head and neck to which such positions are prone.