Purpose: This study is aimed to compare the force sense during neck flexion and extension in normal young (NY), middle-aged (MA) subjects, and patients with cervical spondylosis (CS). Background: The prevalence of cervical degeneration (grade 2-4) was over 60% in populations aged between 45-64 years. The prevalence increased to over 70-85% in the populations aged above 65. In the aged population, the proprioception of the joints declines, and is further impaired by joint damage. In most of the previous studies, the proprioception was evaluated in the aspect of joint position sense. The force sense associated with muscle contractions in patients has not been investigated. Methods: Nineteen NY adults (age, 22.9±3.6), 19 MA adults (age, 55.4±5.0), and 18 CS patients (age, 51.4±6.1) were recruited in this study. The subjects performed isometric maximal voluntary contraction toward flexion (FMVC) and extension (EMVC) in head neutral position recorded by a force transducer. The subjects then performed four force levels: 25% FMVC, 50% FMVC, 25% EMVC, and 50% EMVC. The force error between the force generated by the subject and the target force was calculated in term of percentage absolute error (pAE) and percentage constant error (pCE). One-way analysis of variance (ANOVA) was used to compare the difference among three groups by SPSS 10.0 software. Results: The pCE during 25% and 50% FMVC was significantly higher in CS group than in MA and NY groups (p<0.05). The pAE during 50%FMVC were significantly higher in CS group than in NY group (p<0.05). Conclusions. Natural aging does not show significant effect on force sense. Cervical spondylosis is associated with the decreases of force sense. Furthermore, the combination of pathological process and natural aging show significant decline of force sense. Proper training to improve the force sense in patients with cervical spondylosis is advised.
Purpose: This study is aimed to compare the force sense during neck flexion and extension in normal young (NY), middle-aged (MA) subjects, and patients with cervical spondylosis (CS). Background: The prevalence of cervical degeneration (grade 2-4) was over 60% in populations aged between 45-64 years. The prevalence increased to over 70-85% in the populations aged above 65. In the aged population, the proprioception of the joints declines, and is further impaired by joint damage. In most of the previous studies, the proprioception was evaluated in the aspect of joint position sense. The force sense associated with muscle contractions in patients has not been investigated. Methods: Nineteen NY adults (age, 22.9±3.6), 19 MA adults (age, 55.4±5.0), and 18 CS patients (age, 51.4±6.1) were recruited in this study. The subjects performed isometric maximal voluntary contraction toward flexion (FMVC) and extension (EMVC) in head neutral position recorded by a force transducer. The subjects then performed four force levels: 25% FMVC, 50% FMVC, 25% EMVC, and 50% EMVC. The force error between the force generated by the subject and the target force was calculated in term of percentage absolute error (pAE) and percentage constant error (pCE). One-way analysis of variance (ANOVA) was used to compare the difference among three groups by SPSS 10.0 software. Results: The pCE during 25% and 50% FMVC was significantly higher in CS group than in MA and NY groups (p<0.05). The pAE during 50%FMVC were significantly higher in CS group than in NY group (p<0.05). Conclusions. Natural aging does not show significant effect on force sense. Cervical spondylosis is associated with the decreases of force sense. Furthermore, the combination of pathological process and natural aging show significant decline of force sense. Proper training to improve the force sense in patients with cervical spondylosis is advised.