Efficacy of Deep Cervical Flexor Muscle Training on Neck Pain, Functional Disability, and Muscle Endurance in School Teachers: A Clinical Trial

Background. Neck pain (NP) is a common work-related disorder, with high prevalence in the profession of teaching. The daily duties of a school teacher involve head-down postures while reading and writing, which expose them to the risk of developing NP. Deep cervical flexor (DCF) muscles have been reported to have lower endurance in patients with cervical impairment, which has additionally been associated with disability. There is limited evidence regarding the efficacy of training of DCF muscles in occupational NP. The objective of this study was to investigate the effects of DCF muscle training on pain, muscle endurance, and functional disability using pressure biofeedback in school teachers with NP. Methods. Sixty-five teachers (age, 25-45 years) with more than 5 years of teaching experience participated in this study. They were randomly divided into two groups: the experimental (E) and control (C) groups. In the E group, the subjects underwent DCF muscle training using pressure biofeedback in addition to conventional exercises for neck pain, while those in the C group underwent conventional exercises only. Pain, muscle endurance, and disability were measured at day 0 (before the treatment) and days 14 and 42 after the treatment. Endurance of DCF muscles was measured by the craniocervical flexion test using pressure biofeedback, pain intensity was measured using the numeric pain rating scale, and functional disability was assessed using the neck disability index questionnaire. This study was performed in accordance with CONSORT guidelines. Results. On day 0, there were no significant differences in the age, pain, muscle endurance, and disability levels between the groups. After initiating the intervention, although there were improvements in both groups, there was a statistically significant improvement in muscle endurance, pain, and disability in subjects who received additional training with pressure biofeedback. Conclusions. Besides increasing muscle endurance, specific training of DCF muscles in addition to conventional exercises can improve neck pain and functional disability. These results should be further correlated clinically. A dedicated time for exercises at school could help prevent the development of NP in teachers. This trial is registered with ClinicalTrials.gov May 24, 2018 (retrospectively registered).