Participants, interventions and outcomes
Study setting {9}
The study will be undertaken at the Physiotherapy Department of the Federal University of São Carlos (UFSCar), in the city of São Carlos, São Paulo State, Brazil.
Eligibility criteria {10}
After screening using an online form, the potential participants will be registered and checks will be performed considering the inclusion and exclusion criteria.
Inclusion criteria
- Individuals with complaints of nonspecific neck pain, reported during the screening;
- Neck pain for at least 3 months;
- Numerical rating scale (NRS) score ≥3 for pain intensity;
- Age between 18 and 60 years;
- Men and women;
- Completed primary education;
Exclusion criteria
- Fracture or history of spinal injury;
- Spondylolisthesis;
- Stenosis of the spinal canal;
- Ankylosing spondylitis;
- Signs of radiculopathy;
- Cancer;
- Acute infections;
- Hemorrhagic disease;
- Rheumatological disease;
- Systemic inflammatory disease;
- Rheumatoid arthritis;
- Alteration in skin sensitivity;
- Hearing difficulty (without correction);
- Difficulty in answering questionnaires;
- Pregnancy, puerperium, and breastfeeding;
- Individuals who have started or been submitted to any type of intervention or treatment in the three months prior to the date of screening.
- Individuals who do not accept to remain in the ventral decubitus position, upper limbs along the body and cervical in neutral position, during the time of interventions.
- Individuals who do not having ingested any sedative, anti-inflammatory and analgesic medications (narcotics and non-narcotics), and alcoholic substance in the last 48 hours before the intervention.
Who will take informed consent? {26a}
Data collection will only start after the participants have signed an informed consent form, which will be explained by the evaluator.
Additional consent provisions for collection and use of participant data and biological specimens {26b}
Not applicable for this study.
Interventions
Explanation for the choice of comparators {6b}
No studies were found in the literature that effectively compared Traditional Acupuncture with Laser Acupuncture for treatment of chronic nonspecific neck pain. Therefore, the proposed research will focus on evaluating and comparing changes in pain symptoms and neck functional capacity, after application of TA and LA in cases of chronic nonspecific neck pain.
Intervention description {11a}
The interventions will follow a standardized therapy protocol. Four acupuncture points (Tianzhu, Fengchi, Jianjing, and Jianzhongshu) will be stimulated bilaterally with needles or laser. The participant will be positioned in a ventral decubitus position, upper limbs along the body and cervical in neutral position, asked to rest for 5 minutes, prior to the intervention. At the locations where the needles or laser will be applied, the skin will be hygienized with gauze and 70% alcohol solution. A dermatograph pencil (COLOURED®) will be used to draw circles with diameters of 2 cm around the application points. The same researcher, an acupuncturist with specialization in the field and 9 years of clinical experience, will perform all the interventions. The individuals will be asked not to use any other treatment for neck pain during the study period. All the data collected about the participants will be confidential.
Traditional Acupuncture (TA)
For the TA group, the interventions will be performed using disposable Goldlife® needles (0.25 mm diameter, 40 mm length; Brazilian product registration number MS80553910002) supplied in packages containing 10 surgical steel needles and a needle guide tube. Using the guide tube, the needles will be appropriately positioned in the centers of the areas demarcated on the skin and manually inserted into the muscle to a depth of 20 mm. The acupuncture points (Tianzhu, Fengchi, Jianjing, and Jianzhongshu) will be stimulated bilaterally. The manual needle stimulation technique known as sparrow pecking will be used (35,50,51). After the stimuli, the needles will be left in position for 20 minutes (43,47,52), followed by removal using a stainless-steel collecting cup and disposal in an appropriate container for sharps (Descarpack®), in each session new needles will be used.
Laser Acupuncture (LA)
For the LA group, the interventions will be performed using an Antares® laser (IBRAMED, Amparo, São Paulo, Brazil). The laser probe will be appropriately positioned at the locations demarcated on the skin, the acupuncture points: Tianzhu; Fengchi; Jianjing; Jianzhongshu. The dose (Table 1) being based on previous work using LA for neck pain (47), following the criteria suggested by Baxter (49).
Criteria for discontinuing or modifying allocated interventions {11b}
There will be no changes in the allocations and no migration of individuals between groups will be allowed. If individuals discontinue treatment, recent data will be computed for the analyses according to the intention-to-treat principle, and the motive for the desistence will be recorded.
Strategies to improve adherence to interventions {11c}
To minimize data loss, all the participants in the trial will receive a card with the date and time of session. The therapist responsible for the session will send a WhatsApp message from a cellphone account used only for this research, confirming the session, one day in advance. For the evaluations and reevaluations, the blinded evaluator will contact the participants by WhatsApp, confirming the initial and final evaluations, as well as the follow-up 1 months after the end of the intervention, which will be performed by telephone. In cases of abandonment or impossibility of continuing the study, the data will be analyzed according to an intention-to-treat protocol.
Relevant concomitant care permitted or prohibited during the trial {11d}
Concomitant treatments such as continuous use medications for hypertension and diabetes will be permitted during the trial. The participants will not be permitted to start any new type of intervention or activity during the trial period.
Provisions for post-trial care {30}
A follow-up will be performed by telephone, 1 month after the end of the intervention.
Outcomes {12}
The primary outcome will be the pain intensity before-after data. It will be evaluated using the numerical rating scale (NRS). Secondary outcomes will be as follows: pressure pain threshold (PPT); temporal summation of pain (TS); conditioned pain modulation (CPM); use of analgesic drugs after treatments; and Global Perceived Effect Scale (GPE). These outcomes will be evaluated before and after the treatments. Evaluation using the NRS and the global perceived effect scale will be performed at the end of the 1-month follow-up period.
Numeric rating scale (NRS)
The NRS employs a simple and easy to use scale, where the individual is asked to indicate the intensity of the current pain, using a scale ranging from 0 (“no pain”) to 10 (“worst pain imaginable”) (53). The participants will be instructed to rate the pain experienced at rest and during movements (flexion, extension, lateral inclination to the left and right, and rotation to the left and right). All before-after data will be individually recorded and compared for their respectively positions.
Pressure pain threshold (PPT)
Measurements will be made using a pressure algometer (Somedic®, Hӧrby, Sweden), with the tip of the instrument (1 cm2) positioned on cervical zygapophysial joints C5/6 (54), between C7 and the acromion, bilaterally at the midpoint of the upper trapezius muscle (55), and on the middle third of the right tibialis anterior muscle. All these points will be previously marked with a dermatograph pencil. The algometer probe will be positioned perpendicular to the skin and pressure will be applied at a rate of 40 kPa/s. Three consecutive PPT measurements will be made, with an interval of 30 s between them, and the average value will be recorded. The participants will be instructed to close their eyes and to press the algometer sensor when the pressure sensation becomes painful, with the corresponding value being recorded. A test will be performed to familiarize the individuals with the algometer, explaining the procedure, and a demonstration will be made using the thenar region of the hand. During the actual measurements, the individuals will not be allowed to see the algometer. The intra-examiner reliability of the PPT measurements will be evaluated using measurements at the same points for 10 healthy and asymptomatic individuals, performed by a single examiner at intervals of 48 hours. The reliability will then be estimated by calculating intraclass correlation coefficients (ICC) (54–57).
Temporal summation of pain (TS)
Measurements will be made using the pressure algometer (Somedic®, Hӧrby, Sweden), applying a total of 10 stimuli, at a rate of 40 kPa/s, using the average value from the previous algometry test performed on the most painful upper trapezius muscle (or the dominant side if there is no evident difference). Each stimulus will be maintained for 1 s, using a timer to ensure the correct intervals (1 s). The individuals will be asked about their pain at the 1st, 5th, and 10th seconds of stimulus, using the NRS. In order to avoid any interference, the test will begin 5 minutes after the PPT (57,58).
Conditioned pain modulation (CPM)
Cold nociceptive stimulus will be employed. Individuals will receive instructions before the test. Conditioned stimulus will be provided by the hand on the side ipsilateral to the region of the greatest neck pain, which will be immersed for 1 minute in a water bath kept at 22 °C, in order to standardize the hand temperature. After that, the same hand will be submerged (up to the wrist) for 1 minute in ice water (kept at 4 °C). After 30 seconds, the individual will be asked to report (using the NRS) the intensity of the pain in the hand, caused by the ice water. After immersion for 1 minute, the patient will be asked to remove the hand from the ice water. The PPT will be performed (between C7 and the acromion, at the mid-point of the upper trapezius muscle), using the side contralateral to the immersed hand. The PPT evaluation will be performed before and immediately after the cold stimulus. The mean PPT value before the stimulus will be subtracted from the mean value after the stimulus, with a lower value indicating that the endogenous system is less efficient in inhibiting pain (57,59,60).
Use of analgesic drugs
It will be important to record the use of analgesic drugs, in order to determine whether their use decreased after treatment. The participants will be asked to report, all the medications used. This information will be collected and recorded. In tables, the analgesic medications will be converted into opioids, considering the equianalgesic dose of morphine (61), and non-opioids, considering the equianalgesic dose of acetaminophen (paracetamol) (62).
Global perceived effect scale (GPE)
The global perceived effect scale is used to assess the perception of the individual regarding any improvement, comparing the initial symptoms with the current condition. This scale, which has been translated into Portuguese and validated, provides good reliability when applied to musculoskeletal disorders. It uses 11 points, ranging from -5 (much worse), through 0 (no change), to 5 (completely recovered). After treatment, the participants will be asked: “Compared to when this problem first started, how would you describe the condition of your neck today?” A higher score indicates an improved condition (63,64).
Participant timeline {13}
Sample size {14}
The calculation of the sample size considered a difference of 1.5 points between groups, which would be a clinically relevant value for the outcome of neck pain intensity, as measured using the numeric rating scale (NRS) (65), with an estimated standard deviation of 1.6 points (37). Statistical power of 90% and a possible sample loss of 20% were considered. Consequently, a total of 60 individuals will be needed, with 30 in each group. This calculation was performed using Minitab v.17 software (State College, PA, USA).
Recruitment {15}
Recruitment of participants in the research will be achieved by means of announcements using local media, internet, radio, and posters distributed throughout the city of São Carlos.
Assignment of interventions: allocation
Sequence generation {16a}
The individuals included in the study will be randomized using block exchange methods available at the website http://randomization.com, with allocation to the TA group (n = 30) or the LA group (n = 30).
Concealment mechanism {16b}
Concealment of the allocation will be achieved using sequential numbering, in sealed opaque envelopes, which will only be opened before the first session, by the researcher responsible for application of the treatments.
Implementation {16c}
Randomization will be performed by a researcher responsible only for the randomization, with no other role in this study.
Assignment of interventions: Blinding
Who will be blinded {17a}
The evaluator will be blinded to the randomization and intervention processes, be responsible only for recruitment and evaluations, and receive no information regarding the allocation of the individuals to the groups. The participants and the researcher responsible for the treatment will not be blinded, due to the nature of the interventions.
Procedure for unblinding if needed {17b}
The evaluator will not be allowed to unblock the blinding. However, the acupuncturist researcher responsible for applying the treatments will not be blinded.
Data collection and management
Plans for assessment and collection of outcomes {18a}
The interventions will follow an application protocol. The evaluator will be trained in application of the questionnaires and tests, while intra-examiner reliability will be estimated by calculation of ICC.
Plans to promote participant retention and complete follow-up {18b}
The participants will be provided with guidance when they sign the informed consent form and commit to attending on the scheduled treatment dates. They will receive a card with the dates of the treatment sessions, a contact telephone number, and a WhatsApp contact number used only for this research. This procedure will ensure that participants receive the necessary attention and will assist in fully accompanying them during the research. If individuals abandon the trial, the reasons will be recorded, the most recent data will be compiled, and analysis will be performed using the intention-to-treat principle.
Data management {19}
All the data will be collected weekly, saved as PDF files, and stored on the UFSCar institutional Google Drive. The person responsible for data management will be the principal investigator, namely the acupuncturist researcher who applies the treatments.
Confidentiality {27}
The data will be stored on the institutional Google Drive of Federal University of São Carlos (UFSCar). Only researchers from the UFSCar, who participate in this research, will have authorization to access these stored documents. The metadata will be stored for the long term in the UFSCar research data repository.
Plans for collection, laboratory evaluation and storage of biological specimens for genetic or molecular analysis in this trial/future use {33}
Not applicable to this research.
Statistical methods
Statistical methods for primary and secondary outcomes {20a}
The statistical inferences for the primary and secondary outcomes will be made by an assessor blinded to the randomization and assessment processes. The intention-to-treat principle will be adopted in the analyses. The normality of the data will be evaluated using the Kolmogorov-Smirnov test. Specific analyses will be used, depending on the distribution (normality and homogeneity) of the data. Parametric and nonparametric analyses will be used for normally and non-normally distributed data, respectively. These analyses will be performed using SPSS v.17 statistical software (SPSS, Inc., IL, USA), considering a statistical power of 90% for all the tests, with a significance level of p < 0.05.
Interim analyses {21b}
No provisional analyses will be performed. In cases of discontinuity, the intention-to-treat principle will be adopted.
Methods for additional analyses (e.g. subgroup analyses) {20b}
No subgroups will be analyzed.
Methods in analysis to handle protocol non-adherence and any statistical methods to handle missing data {20c}
In the case of discontinuity, missing data will be handled by adopting the intention-to-treat principle, in order to make statistical inferences.
Plans to give access to the full protocol, participant level-data and statistical code {31c}
Not applicable to this research.
Oversight and monitoring
Composition of the coordinating center and trial steering committee {5d}
Not applicable to this research.
Composition of the data monitoring committee, its role and reporting structure {21a}
Data monitoring committees are usually established for large studies. The present study is not multi-center and will be performed at UFSCar. The researcher will be responsible for organizing and monitoring the data obtained in this research.
Adverse event reporting and harms {22}
In the case of any harm or complication related to the treatments, this will be reported to the UFSCar Ethics Committee for Human Research. The same applies to possible ethical issues that may arise during the research. The guideline recommendations will be strictly followed.
Frequency and plans for auditing trial conduct {23}
Not applicable to this research.
Plans for communicating important protocol amendments to relevant parties (e.g. trial participants, ethical committees) {25}
This study it was registered with RBR-7vbw5gd (Brazilian Registry of Clinical Trials - ReBEC) and there will be no substantial alterations to the protocol, such as changes in the eligibility criteria and analyses. If there is any modification, it will be reported in writing, in a document sent to the trial registration office.
Dissemination plans {31a}
After publication of the results in a scientific journal, all data will be available over the long term and kept in the UFSCar research data repository.