Effects of Cervical and Scapular Stabilization Exercises on Head Posture and Muscle Activity in Individuals with Cervical Extension Type: A Randomized Controlled Trial

Background: Cervical extension type is commonly associated with forward head posture and altered cervical and scapular muscle activity. However, the comparative effects of cervical stabilization exercises combined with scapular stabilization exercises or thoracic exercises remain unclear. Objective: In this study, we aimed to compare the effects of cervical stabilization exercises combined with scapular stabilization exercises and cervical stabilization exercises combined with thoracic exercises on head posture and muscle activity in individuals with cervical extension type. Methods: Thirty-two university students with cervical extension deformity were randomly assigned to either a cervical spine stabilization combined with scapular stabilization training group or a cervical spine stabilization combined with thoracic spine training group. Baseline demographic and anthropometric characteristics, including sex, age, height, weight, and body mass index, were comparable between the groups. Both groups received a 4-week intervention consisting of stretching, strengthening, and postural correction exercises, performed three times per week. Head posture was assessed using the craniovertebral angle (CVA) and cranial rotation angle (CRA), and the muscle activity of the sternocleidomastoid (SCM), upper trapezius (UT), lower trapezius (LT), and serratus anterior (SA) was measured using surface electromyography. Paired t-tests and two-way repeated measures ANOVA were used for statistical analysis. Results: No significant differences were observed in the general characteristics between the two groups at baseline. After the intervention, both groups showed significant improvements in CVA and CRA compared with baseline. Compared with the CTG, the CSG showed significantly greater reductions in SCM and UT activity and significantly greater increases in LT and SA activity. Significant time effects and group-by-time interaction effects were identified for selected head posture and muscle activity variables. Conclusion: Cervical stabilization exercises combined with scapular stabilization exercises may be more effective than cervical stabilization exercises combined with thoracic exercises in improving head posture and optimizing neck and scapular muscle activity in individuals with cervical extension type.