LATEST BUZZ FROM KC

What's happening at the neck

13th March 2013


Two recent papers relating to neck muscle dysfunction in neck pain and a nice facilitation strategy


Is there altered activity of the extensor muscles in chronic mechanical neck pain? A functional magnetic resonance imaging study.

O'Leary S, Cagnie B, Reeve A, Jull G, Elliott JM.

Arch Phys Med Rehabil. 2011 Jun;92(6):929-34. doi: 10.1016/j.apmr.2010.12.021. Epub 2011 May 6.

 

Abstract


Objective:
To compare the pattern of neck extensor muscle use in participants with chronic mechanical neck pain to that of healthy controls during 2 different extension exercises by use of muscle functional magnetic resonance imaging (mfMRI).


Design:
Cross-sectional.


Setting:
University laboratory.


Participants:
Data recorded from subjects with chronic mechanical neck pain (n=12; 10 women, 2 men) were compared with previously recorded data from healthy subjects (n=11; 7 men, 4 women).


Interventions:
Not applicable.


Main outcome measures:
mfMRI measures of shifts in T2 relaxation were made for the multifidus, semispinalis cervicis, semispinalis capitis, and splenius capitis muscles, at C2-3, C5-6, and C7-T1 levels, prior and immediately after 2 different exercises: cervical extension in craniocervical neutral (CCN) and cervical extension in craniocervical extension. T2 shift values (difference between pre- and postexercise T2 relaxation values) for each muscle and exercise condition were used for analysis.


Results:
While there were observed differences in differential activation of the extensor muscles in participants with mechanical neck pain compared with controls, these differences were only evident for the CCN exercise condition and were only observed for 3 out of the 7 muscle regions of interest during this exercise.


Conclusions:
Results of this study suggest some alteration in the differential activation of the cervical extensors in patients with mechanical neck pain and indicate that further investigation of this muscle group in mechanical neck pain disorders is warranted.

 

Localised resistance selectively activates the semispinalis cervicis muscle in patients with neck pain.

Schomacher J, Petzke F, Falla D. S

Man Ther. 2012 Dec;17(6):544-8. doi: 10.1016/j.math.2012.05.012. 2012

Abstract

The semispinalis cervicis muscle displays reduced and less defined activation in patients with neck pain which is associated with increased activity of the splenius capitis muscle.

Exercises to selectively activate the semispinalis cervicis muscle may be relevant for patients with neck pain however the most appropriate type of exercise has not been determined.

The purpose of this study was to investigate whether a specific exercise could selectively activate the semispinalis cervicis muscle relative to the splenius capitis.

Ten women with chronic neck pain participated. Intramuscular electrodes were inserted into the semispinalis cervicis and splenius capitis unilaterally on the side of greatest pain.

After testing the maximal neck extension force, three isometric exercises were performed in sitting: 1. the investigator placed a hand on the patient's occiput and pushed into flexion asking the patient to resist into extension maximally, 2. the investigator placed the thumb and index finger on the vertebral arch of C2 and pushed into flexion asking the patient to resist maximally, 3. same procedure as for C2 however the resistance was applied at C5.

The ratio between the normalized electromyography (EMG) amplitude of the semispinalis cervicis and splenius capitis was computed. The relative activation of the semispinalis cervicis was greater (P < 0.05) than the splenius capitis with resistance at C2 (2.53 ± 2.43) compared to resistance at the occiput (1.39 ± 1.00) or at C5 (1.16 ± 0.85).

The results indicate that localized resistance can achieve relative isolation of the semispinalis cervicis muscle. This exercise approach may be relevant for patients with neck pain.

 

Keywords: Review 2013