ABSTRACT
OBJECTIVES: To compare mechanical activity (deformation and deformation rate) of the dorsal neck muscles between individuals with longstanding symptoms after anterior cervical decompression and fusion (ACDF) surgery and healthy controls. DESIGN: Preliminary cross-sectional study. SETTING: Neurosurgery clinic. PARTICIPANTS: Ten individuals {mean age 60 [standard deviation (SD) 7.1]} who had undergone ACDF surgery 10 to 13 years previously and 10 healthy age- and sex-matched controls. MAIN OUTCOMES: Mechanical activity of the different layers of dorsal neck muscles, measured at the C4 segment using ultrasonography (speckle tracking analysis) during a standardised, resisted cervical extension task. RESULTS: A significant group×muscle interaction was found for muscle deformation (P<0.03) but not for deformation rate (P>0.79). The ACDF group showed significantly less deformation of the semispinalis capitis muscle during the extension task compared with the control group [mean 3.12 (SD 2.06) and 6.64 (SD 4.17), respectively; mean difference 3.34 (95% confidence interval -0.54 to 7.21)]. CONCLUSIONS: As the semispinalis capitis muscle is a powerful neck extensor, the finding of altered activation following ACDF surgery lends support to the inclusion of exercise to train neck muscle performance in the management of these patients.