Effects of 1-hour computer use on ulnar and median nerve conduction velocity and muscle activity in office workers.

OBJECTIVES: To compare the effects of 1-hour computer use on ulnar and median nerve conduction velocity and muscle activity in office workers with symptomatic neck pain and asymptomatic office workers. METHODS: A total of 40 participants, both male and female office workers, with symptomatic neck pain (n = 20) and asymptomatic (n = 20), were recruited. Pain intensity, ulnar nerve conduction velocity, median nerve conduction velocity, and muscle activity were determined before and after 1 hour of computer use. RESULTS: There was a significant increase in pain intensity in the neck area in both groups (P < .001). The symptomatic neck pain group revealed a significant decrease in the sensory nerve conduction velocity of the ulnar nerve (P = .008), whereas there was no difference in the median nerve conduction velocity (P > .05). Comparing before and after computer use, the symptomatic neck pain group had less activity of the semispinalis muscles and higher activity of the anterior scalene muscle than the asymptomatic group (P < .05). The trapezius and wrist extensor muscles showed no significant differences in either group (P > .05). CONCLUSIONS: This study found signs of neuromuscular deficit of the ulnar nerve, semispinalis muscle, and anterior scalene muscle after 1 hour of computer use among office workers with symptomatic neck pain, which may indicate the risk of neuromuscular impairment of the upper extremities. The recommendation of resting, and encouraging function and flexibility of the neuromuscular system after 1 hour of computer use should be considered.

Effects of scapular stabilization exercises on posture and muscle imbalances in women with upper crossed syndrome: A randomized controlled trial.

BACKGROUND: Scapular stabilization exercises can improve forward shoulder posture in young women. However, the effects of optimal exercise protocols on neck and shoulder postures, scapular muscle imbalance and thoracic kyphosis are still unclear. OBJECTIVES: To investigate the effects of scapular stabilization exercises on neck and shoulder postures, scapular muscle imbalance and thoracic kyphosis in young women with upper crossed syndrome. METHODS: Thirty-nine women aged 18-25 years with upper crossed syndrome were recruited. Participants were randomly allocated intotwo groups. The exercise group performed scapular stabilization exercises using elastic bands at 10 repetitions/set, 3 sets/day, and 3 days/week for 4 weeks. The control group did not perform any exercises during the experimental period. The cervical and shoulder angles were evaluated using the Kinovea program. A caliper, handheld dynamometer and flexi ruler were used to evaluate the length of the pectoralis minor, strength of the scapular stabilizer muscles and degree of the mid-thoracic curve, respectively. RESULTS: The exercise group showed significant differences (p< 0.05) in the increase in cervical and shoulder angle, length of the pectoralis minor, and strength of the scapular muscles, except in the degree of mid-thoracic curve compared to the control group. CONCLUSION: This study indicated that scapular stabilization exercises can improve forward head and shoulder posture, increase the flexibility of the pectoralis minor and strengthen the scapular muscles.