Characteristics of Biomechanical Kinematics and Neuromuscular Adaptation for Patients with Mechanical Neck Disorder

• Main Authors: Chia-ChiYang, 楊家琪
• Other Authors: Fong-Chin Su
• Format: Others
• Language: en_US
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/93343012443963318396

博士 === 國立成功大學 === 生物醫學工程學系 === 103 === Mechanical neck disorder is commonly viewed as a widespread and unnerved musculoskeletal condition in modern lifestyle. Not only the prevalence of neck pain in the general population is considerably high, but the rate of recurrence of neck pain is also increasing. Although the etiology of MND is largely under debate, MND has attracted attention in clinical setting and research field for a long period of time and the threat to healthy issues is still getting more and more severe. Despite aberrant cervical mobility in patients with MND, published evidences still fail to comprehend thoroughly the complicated biomechanical kinematics because of the complexity of the anatomical structures of the cervical spine. Therefore, the objectives of this current dissertation aimed to further clarify the three-dimensional kinematics of the cervical spin for patients with MND and asymptomatic populations from quantitative biomechanical assessments. The concept of the three-dimensional workspace was modified to describe the complicated kinematics of the cervical spine during circumduction, which integrated the movements of all major anatomical planes instead of the conventional angular parameters. Furthermore, the quality of the kinematics of the cervical spine, such as the smoothness of movement during cervical circumduction was simultaneously observed using the concept of spectral entropy. On the other hand, since the motor units are fundamental functional units of the neuromuscular system and dysfunction in the cervical flexor muscles, especially the sternocleidomastoid muscles, has been found to be associated with neck pain, the electrophysiological properties of the motor units of the sternocleidomastoid muscles were also characterized. Based on the findings of the current dissertation, it was found that the workspace during cervical circumduction was successfully proposed to be a feasible and alternative mathematical model for assessing the complicated kinematics of the cervical spine quantitatively, reporting significant reduction in the normalization of the cervical workspace. Meanwhile, less smooth cervical movements in patients with MND was identified in contrast to asymptomatic individuals. Finally, patients with MND exhibited higher values of initial and mean firing rates and lower short-term synchronization of the motor units pairs of the sternocleidomastoid muscles. Thus, these convinced evidences indicated that patients with MND might be more likely to modify motor control strategies to execute the cervical activities of daily living due to alternations in neural recruitment strategies of the motor units, such as increased recruitment firing rates of the motor units of the sternocleidomastoid muscles. These valuable information could further offer a clinical relevance for clarifying characteristics of motor control strategies for patients with MND and allow guiding the clinicians to evaluate the extent of impairment of the cervical spine easily and quickly and monitor the efficacy of rehabilitation programs in patients with MND in clinical practice.