Ellen Vandyck
Research Manager
In this study, progressive neck-shoulder exercise was studied in women with chronic headache
Neck-shoulder exercise was feasible, safe, and effective in reducing headache frequency more compared to the control intervention
The primary outcome of this study, pain intensity, revealed no significant between-group differences
Chronic headaches due to migraines, tension-type headaches, and cervicogenic headaches are among the most common causes of headaches in physical therapy practice. Many studies have focused on active and passive treatments, but the evidence for those treatments remains low. If there is evidence available, it mostly includes a multimodal intervention arm, of which we do not know which intervention now contributes to the effects that have been found. Therefore, the aim of this RCT was to investigate the effects of a single-component exercise approach compared to a control intervention on pain intensity in people with chronic headaches.
For a period of 6 months, a randomized controlled trial was conducted at two locations in Finland. The RCT included working-aged women (18-60 years) who reported having headaches for at least 8 days over the previous 4 weeks with a pain intensity of at least 4/10 on the Visual Analogue Scale (VAS). Also, a minimum score of 56 points on the Headache Impact Test, meaning substantial impact on daily life activities, was required to be included in the RCT.
The intervention group completed a 6-month progressive Neck-Shoulder Exercise program, consisting of six modules. In the first three modules, low-load exercises were performed while the remaining modules required specific strength exercises for the neck and upper body, supplemented with stretching exercises. The first and second modules were individually supervised and the remaining four were held in small groups. An additional home exercise program was guided by an instructional booklet and videos. Here participants were advised to complete the home exercise program at least 6 times per week in the first 4 modules (the first 3 months) and 4 times per week in the last 3 months.
The control intervention consisted of 45 minutes individually supervised sessions with 20 minutes of so-called placebo transcutaneous electrical nerve stimulation (TENS). These sessions were held once a month for 6 months. From the third session on, participants in the control group also performed the same 3 stretching exercises.
Pain intensity measured on the VAS from 0-10 was the primary outcome of interest.
The primary outcome, headache intensity, was equal at baseline, with a mean of 4.7/10 in the intervention group and 4.8/10 in the control group. Over the 6-month intervention, the headache intensity decreased by -0.6 (standard deviation 1.3) in the intervention group performing the Neck-Shoulder Exercise program and by -0.4 (SD: 1.3) in the control group. There was no between-group difference in pain intensity.
The mean headache frequency at baseline was 4.5 (95% CI 3.9-5.1) and 4.4 (95% CI 3.6-5.1) in the intervention and control groups, respectively. In the first group, this decreased with -2.2 (SD 2.3) days and in the latter with -1.2 (SD 2.9) days respectively. This led to a significant difference between the groups with a moderate effect size of 0.53, favoring the Neck-Shoulder exercise intervention.
The mean weekly duration of headache episodes was 30.8 (95% CI 24.7-36.9) hours per week in the intervention group and 30.5 (95% CI 23.9-37.1) hours per week in the control group at baseline. This decreased in both groups, with 11.3 (SD 23.5) hours per week in the intervention group performing neck-shoulder exercises and 5.6 (SD 26.0) hours per week in the control arm. This led to a non-significant difference between the groups.
Other outcomes revealed an increase in neck flexor endurance time of 22 seconds more in the intervention group. This was reflected also in the percentage of people attaining the maximum of 180 seconds on the neck-flexor endurance test. At baseline, this was 72% of the participants in the intervention group and 79% of those in the control group. This increased to 93% of women in the intervention group and decreased to 71% in the control group. The improvement in cervical rotation was markedly improved with 8° more in the intervention group.
The Neck Disability Index and Headache Impact Test showed only minor changes.
Pain intensity was the primary outcome of interest. Unfortunately, in chronic pain conditions, this may not fully reflect the complexity of the chronic pain experienced. In my opinion, a functional outcome as the primary outcome measure may have been of greater value. In fact, that’s what our profession does. We don’t cure pathologies or pain. With physiotherapy, the intent is to get someone better moving, thereby stimulating the body’s natural healing capacity. Although the study was not powered to detect differences in other outcomes, rather than using pain as an outcome, the headache frequency and duration could have been of more value. To note, there was no report of whether or not patients used analgesic drugs. Though, it was used as a covariate in the analysis.
What I missed in this study was a responder analysis to inform whether there would exist subgroups of people better reacting to treatment. Especially as the included chronic headache population in this study had different headache origins (migraine, tension-type headache, cervicogenic headache, cervical spondylosis)
Some aspects of the study’s methodology can be discussed. For example, the patients were informed about the randomization in either the neck-shoulder exercise group or the TENS group. However patient blinding would be difficult as in many physiotherapy trials, but people may already have an idea of the preferred treatment option. The treating physiotherapist was aware of the patient’s allocation, which is logical. Yet, he was the one who measured the isometric strength of the neck flexor and extensor muscles. This may, unintentionally, create some bias toward the intervention tested. Fortunately, the isometric strength was not the primary outcome measure because that could have potentially influenced the results. I assume that other outcomes were captured through the questionnaires and there, the statistician was unaware of group allocation, so in the primary outcome measure this wouldn’t be an issue.
Another point to bear in mind is the difference in treatments between the groups. Where the shoulder-neck exercise group followed a total of 8 supervised sessions, the TENS group only followed a total of 6 sessions.
Important to note for the applicability of these results to your patient population is that the participants with severe degenerative changes were excluded from participating in the study. Same for people who are participating in habitual physical activity three or more times per week. This would mean that these results wouldn’t be applicable to more active participants you possibly see in clinical practice and to those with severe degeneration (although the definition of severe was not specified). Either way, I applaud the authors for having chosen a more sedentary set of participants to include. Often when you see exercise trials inclusion criteria, they tend to include more active participants, who may possibly respond better as they know the benefits of exercise.
This trial with shoulder and neck exercises for a chronic headache population did not find a significant decrease in headache intensity over 6 months when compared to TENS. However, the frequency of the headache episodes decreased more in the exercise group over the course of the 6-month study, with a moderate effect size.
Download this FREE home exercise program for your patients suffering from headaches. Just print it out and hand it to them for them to perform these exercises at home