Prospective Comparison of Age- and Sex-related Differences in Quantifiable 10-S Grip and Release and 10-S Step Test Results for Diagnosis of Cervical Spondylotic Myelopathy in 454 Patients With Cervical Spondylotic Myelopathy and 818 Asymptomatic Subjects

Study Design. A prospective comparison. Objective. The purpose of this prospective study was to verify the clinical effectiveness of the 10-s grip and release (G&R) and 10-s step quantitative tests for assessing the severity of cervical spondylotic myelopathy (CSM) and to compare age-and sex-related differences in the results between large cohorts of CSM patients and asymptomatic subjects. Summary of Background Data. To determine the severity of CSM, objective and reproducible means of measuring patient disability are essential. No studies have evaluated differences in quantitative test results between a large series of CSM patients and healthy subjects. Methods. Four hundred fifty-four CSM patients and 818 asymptomatic subjects were included. The Japanese subjects were in their 40s to 70s and were divided according to their age by decade. The 10-s G&R and 10-s step tests were used to quantitatively assess performance. The severity of myelopathy before surgery was evaluated according to a scoring system proposed by the Japanese Orthopaedic Association for cervical myelopathy (JOA score) in the CSM patients. Results. In the CSM patients, the 10-s G&R and step test results significantly correlated with the JOA score (P<0.0001). The number of the 10-s G&R and step tests significantly decreased with age in both groups. There was a difference in the 10-s G&R and step test results between males and females. In the asymptomatic subjects, the number of the 10-s G&R and step tests in the females was less than that in the males. The numbers in the 10-s G&R and step tests were significantly lower in CSM patients than those in asymptomatic subjects in each decade (P<0.01). Conclusion. The 10-s G&R and 10-s step tests were useful for quantitatively assessing CSM severity, and age and sex differences in results should be considered in screening.