Effect of Handheld Vibration Therapy Device on Upper Trapezius Tightness and Cervical Mobility

Background: Upper trapezius tightness is a common musculoskeletal problem associated with increased muscle stiffness, restricted cervical mobility, altered posture, and functional limitations. Handheld vibration therapy provides localized mechanical stimulation to soft tissues and may reduce muscle stiffness and improve mobility; however, evidence regarding its effects on objectively measured upper trapezius stiffness together with cervical range of motion remains limited. Objective: To evaluate the short-term effects of handheld vibration therapy on upper trapezius muscle stiffness and cervical mobility in individuals with upper trapezius tightness. Methods: A randomized controlled pretest-posttest study was conducted among 40 participants aged 18–45 years with clinically identified upper trapezius tightness. Participants were randomly allocated in a 1:1 ratio to a handheld vibration therapy group (n=20) or a conventional physiotherapy control group (n=20). The experimental group received vibration therapy at 40 Hz for 5 minutes per side, three sessions per week for three weeks. Upper trapezius stiffness was assessed using MyotonPRO, while cervical flexion, extension, and right and left rotation were assessed using a cervical range-of-motion device. Within-group and between-group comparisons were performed, and treatment effects were reported with 95% confidence intervals and Cohen’s d. Statistical significance was set at p<0.05. Results: Upper trapezius stiffness decreased from 312.6 ± 35.4 N/m to 254.8 ± 30.7 N/m in the vibration therapy group, compared with 310.8 ± 34.9 N/m to 295.6 ± 33.8 N/m in the control group. At post-treatment assessment, muscle stiffness was significantly lower in the vibration group (mean difference: −40.8 N/m; 95% CI: −61.47 to −20.13; p<0.001; Cohen’s d=1.26). Significant between-group differences favoring vibration therapy were also observed for cervical flexion (mean difference: 6.2°; 95% CI: 2.16–10.24; p=0.004; d=0.98), extension (8.3°; 95% CI: 3.59–13.01; p=0.001; d=1.13), right rotation (8.7°; 95% CI: 3.61–13.79; p=0.001; d=1.09), and left rotation (7.3°; 95% CI: 2.08–12.52; p=0.007; d=0.90). Conclusion: Handheld vibration therapy produced greater short-term improvements in upper trapezius muscle stiffness and cervical mobility than conventional physiotherapy. These findings suggest that vibration therapy may be a useful adjunct intervention for individuals with upper trapezius tightness; however, larger randomized trials with longer follow-up are required to establish its sustained clinical effectiveness.