[Comparison of cervical extensor muscles thickness in females with chronic nonspecific neck pain and healthy individuals by ultrasonography]

Objective: Neck pain is one of the most common musculoskeletal disorders. Structural and functional alteration of cervical muscles is a commonly-reported complication of chronic neck pain [CNP]. Measurement of muscle thickness is an acceptable way to evaluate muscle morphological structure. Therefore, this study aimed to measure cervical extensor muscles thickness in individuals with chronic nonspecific neck pain and healthy controls using ultrasonography so as to evaluate structural differences between the 2 groups

Materials and Methods: A total of 30 female volunteers [15 individuals with nonspecific CNP and 15 controls] participated in this casual comparative study. Thickness of cervical extensor muscles, including multifidus, semispinalis cervicis, semispinalis capitis, splenius capitis, and upper trapezius at the level of the forth cervical vertebrae were measured using ultrasonography in resting position. Independent t-test was performed to analyze the data by using the spss 20 software

Results: The thicknesses of cervical multifidus and semispinalis cervicis muscles in patients with CNP were smaller than those of controls with P=0.03 and P=0.01, respectively. There were no significant differences between two groups regarding the thicknesses of semispinalis capitis, splenius capitis, and upper trapezius muscles [P>0.05]

Conclusion: Reduced multifidus and semispinalis cervicis thickness seen in the present study indicates deep neck extensor muscles atrophy and weakness in patients with neck pain. However, there were no differences between two groups with regard to superficial muscles thicknesses. Accordingly, exercise therapy for deep muscles should be considered in the management of patients with nonspecific CNP

Effects of temperature on wrist flexor muscles endurance

Background: It is widely recognized that neuromuscular function is temperature sensitive. Changes in muscle temperature may affect muscle force development. The aim of this study was to investigate the effects of temperature on wrist flexor muscles endurance

Methods: Fifteen healthy subjects [mean age 21.13 +/- 1.30 years] participated in the present study. The wrist flexor muscles endurance was measured before and after applying ice and hot packs over the forearm for 15 minutes. Paired t tests were used to compare differences between pre and post intervention endurance

Results: The results showed a significant increase in wrist flexor muscles endurance after heating. [P=0.04]. We also found that, cooling the forearm muscles leaded to significant decrease of wrist flexor muscles endurance [P=0.01]

Conclusion: These results suggest that hand function is temperature sensitive. Therefore, further studies are needed to evaluate the effects of cold on muscular function in people working in workplaces with extreme temperature