Introduction

Mechanical neck pain is a prevalent condition that can greatly influence an individual’s physical well-being and quality of life. The neck pain can result from a variety of factors, but lacks a clear underlying medical problem (such as for example a herniated disc). Therefore it is also called nonspecific neck pain. It is thought that the pain arises from the joints, ligaments or muscles located in the neck region, but it may interact with posture, repetitive activities, or psychosocial and behavioral factors. Many treatment options exist, but the current clinical practice guidelines recommend manual therapy and/or dry needling combined with scapulothoracic exercises in case of neck pain with mobility deficits. Yet, it is not known whether treatment is superior, since few studies compared manual therapy to dry needling directly. Therefore, this study compared dry needling plus exercise to manual therapy plus exercise for improving neck pain intensity and limitations.

Methods

This study recruited people with mechanical neck pain (or nonspecific neck pain) from a convenience sample of people consulting a physical therapy clinic in Indiana. They suffered from neck pain that was intermittent or constant.

Two groups were compared in this RCT. The first group received manual therapy plus exercise while the second group had dry needling plus exercise. Both groups had seven 30-minute treatments over 6 weeks where 15 minutes were allocated to either receiving manual therapy or dry needling and the other 15 minutes were spent performing the exercises.

The people randomized to receive manual therapy plus exercise had three thrust manipulations targeted to the cervicothoracic junction, upper thoracic spine, and middle thoracic spine. They also underwent cervical mobilizations at the most hypomobile segment and the segments above and under this hypomobile cervical spine segment. These mobilizations were central posterior-anterior glides and unilateral posterior-anterior glides.

In the group randomized to receive dry needling plus exercise, participants were in prone while the clinician targeted the posterior musculature of the cervical spine. They palpated to find trigger points in the following 5 muscles attached to the cervical and thoracic spine:

• Rectus Capitis Posterior (Major and Minor)
• Splenius Capitis and Cervicis
• Cervical Multifidus
• Upper Trapezius
• Levator Scapulae

All these muscles were needled, irrespective of having symptoms upon palpation or not. This way they had at least 10 sites needled, and maximally 20 sites.

The exercises that both groups performed were:

1. Supine deep neck flexor head lift 
2. Active cervical range of motion
3. Seated upper trapezius stretch
4. Prone middle trapezius strengthening 
5. Prone lower trapezius strengthening 

The primary outcome was the between-group difference on the Neck Disability Index. Here, a maximum score of 50 is calculated as a percentage, with higher scores indicating more disability. The minimally clinically important difference (MCID) for nonspecific neck pain is 5.5 points out of 50 or 11%. The outcomes were assessed at baseline, 2 weeks, discharge (after 7 treatment sessions), and at 12 weeks post-discharge.

Secondary outcomes included: 

1. The Numeric Pain Rating Scale (NPRS) to assess pain, 
2. Patient-Specific Functional Scale (PSFS) to measure a function that was relevant to the patient,
3. Fear Avoidance Belief Questionnaire (FABQ) to assess fear of pain and avoidance of cervical spine movements during physical activities; 
4. Deep Neck Flexor Endurance Test (DNFET) to assess deep neck flexor muscle strength; and 
5. Global Rating of Change (GROC) to assess self-perceived improvement.

Results

A total of 78 participants were recruited and 40 were randomly assigned to receive manual therapy plus exercise while 38 were allocated to dry needling plus exercise. The groups were similar at the start of the study. 

Both groups had comparable scores on the Neck Disability Index of about 28 points at baseline. The primary outcome analysis revealed that both groups improved. Still, the manual therapy plus exercise group improved to a greater extent, resulting in a significant between-group difference favoring manual therapy plus exercise at 2 weeks, at discharge, and at 3 months post-discharge. This between-group difference exceeded the minimally clinically important difference of 11 points for the Neck Disability Index at 3 months. 

The within-group improvements for the manual therapy plus exercise group also exceeded the minimally clinically important difference of 11 points at all time points (2 weeks, discharge, and 3 months). In the dry needling plus exercise group, the within-group improvements only exceeded the minimally clinically important difference of 11 points at discharge, but this was not true at the 3-month assessment, since the score at discharge was lower than the 3-month follow-up score. 

No major adverse events were reported. Only a few minor adverse events were reported in both groups, as depicted here.

All secondary outcomes analyses supported the findings of superior outcomes in the manual therapy plus exercise group, except for the Deep Neck Flexor Endurance Test where both groups improved equally. This is probably since both groups participated in the same exercises and also specifically performed the deep neck flexor strengthening exercise. 

Interestingly, the participants who had received manual therapy attended fewer sessions, even after discharge than those in the dry needling plus exercise group. This is important because manual therapy often gets criticized for making patients reliant on the treatment. This was however not studied here, but it gives an important insight to counter this criticism.

The GROC revealed scores of +6 in the manual therapy plus exercise group and this approximated the maximum score of +7 meaning that this group rated their complaints to be a very great deal better than they were at baseline.

Questions and thoughts

The manual therapy interventions were partly prescriptive and partly pragmatic. In a pragmatic study design, the treating clinician can choose how to treat a person based on the examination findings for that particular patient whereas in prescriptive studies, the clincian only can apply a predetermined treatment technique. The first more closely resembles clinical practice as it is addressed to specific impairments found. 

Inconsistent and poor outcomes of manual therapy are thought to result from the prescriptive methodologies used in studies. (Short, 2023) This can be necessary to improve internal validity and adhere to the medical model of research but neglects clinical practice where you can not work with a standardized one-treatment-fits-all approach. Like at school, you’ve probably learned to conduct an examination and to use the findings to determine your treatment path, which you readapt based on changes in complaints along the way. So why would you use the same technique in every nonspecific neck pain patient in the clinic in the first place? Therefore, I understand why the current study combined both approaches, on the one hand, to suit an RCT design, and on the other hand, to truly try to resemble clinical practice as much as possible in this rigorous study design.

Interesting about this study was the fact that the intervention was split in half: 15 minutes of either manual therapy or dry needling and 15 minutes of exercising. Often in research we see that when an intervention is compared to another, most of the time, the interventions are taking up a big part of the scheduled time. Here, the interventions lasted as long as the exercises, and in my opinion, this may be valuable since much criticism of the use of manual therapy and dry needling is because of the passive nature of the interventions. Here the authors point out that doing exercises is equally important and this in turn might be important to translate this message to the patient. 

As a manual therapist myself, I found it interesting to learn more about the procedures used in this study. The only thing I wondered is why the dry needling group had at least 10 sites needled in the 5 muscles listed above, irrespective of symptoms. Maybe, some participants had no trigger points and, therefore did not need dry needling, which may explain why the dry needling group had inferior results. Possibly, the participants presenting had certain mobility problems that responded well to the passive joint mobilizations, but it is unsure since this was no inclusion criterion. On the other hand, the randomization made groups equal at baseline, but it was not assessed beforehand what was the major driver of the neck pain, whether it be mobility or strength deficits, and this may be a limitation.

Talk nerdy to me

The trial was registered and no protocol deviations occurred. The trial was reported following the CONSORT Guidelines.

The treating clinicians received three hours of training to ensure they treated the participants in a standardized manner. They were practicing clinicians for a mean of 7.4 years and had on average 5.6 years of dry needling experience. The outcome assessor was blinded to the participant’s group allocation and was trained about the data collection for 3 hours. They had a mean of 11 years of experience.

A sample size calculation was performed a priori and determined that at least 30 participants per group were required to find a minimal clinical improvement of 11 percentage points on the Neck Disability Index. The group receiving manual therapy plus exercise had improved more on the Neck Disability Index compared to those receiving dry needling plus exercise at 3 months and was therefore superior to dry needling plus exercise. This difference in favor of the manual therapy group was above the minimally clinically important difference at 3 months post-discharge. 

Take home messages

This study compared manual therapy combined with exercises to dry needling combined with exercises for nonspecific neck pain. The results concluded superior effects in self-reported neck pain-related disability at 2 weeks, discharge, and 3 months. These effects were above the minimal important difference at all time points. As such, manual therapy combined with exercise was more effective in the short- and intermediate-term than dry needling plus exercise. 

Reference

Pandya J, Puentedura EJ, Koppenhaver S, Cleland J. Dry Needling Versus Manual Therapy for Patients With Mechanical Neck Pain: A Randomized Controlled Trial. J Orthop Sports Phys Ther. 2024 Apr;54(4):1-12. doi: 10.2519/jospt.2024.12091. PMID: 38284367.  

Additional reference

Roenz D, Broccolo J, Brust S, Billings J, Perrott A, Hagadorn J, Cook C, Cleland J. The impact of pragmatic vs. prescriptive study designs on the outcomes of low back and neck pain when using mobilization or manipulation techniques: a systematic review and meta-analysis. J Man Manip Ther. 2018 Jul;26(3):123-135. doi: 10.1080/10669817.2017.1398923. Epub 2017 Nov 20. PMID: 30042627; PMCID: PMC6055961.