Study design
Data for this randomized controlled trial (RCT) study, adhering to the CONSORT statement [20, 21], included a short treatment period (19 days) of postural taping with Balance Body Tape (BBT). Subjects were randomly assigned, by lottery, into intervention- and control group. The subjects in the intervention group received treatment with BBT whereas the subjects in the control group received no treatment. A questionnaire regarding pain and a Photographic posture analysis measurement (PPAM) of habitual sitting posture, focusing on neck posture, were accomplished at baseline and after 22 days for both groups.
Subjects
Subjects were recruited by advertisements at a University in the southern part of Sweden, through the Student Union and a Business Incubator on the University area and on social media (Facebook and Instagram). Subjects that showed interest to participate (n = 39) received more information about the study through e-mail or a printed information paper. The study included subjects aged 18–39 who reported being a university student or having a sedentary work and at inclusion had at least a 2-point score at the Numeric Rating Scale [22] regarding to self- perceived pain, ache, discomfort or fatigue in neck, shoulders or back associated with prolonged sitting [23]. Subjects who had suffered from severe back or neck injuries within the last 3 months or had an ongoing treatment plan for any back or neck problems were excluded. Subjects that had severe contact allergy or eczema or got skin reaction at the first application and, subjects who had previously tried BBT, were also excluded. Thirty-one subjects where finally included in the study and were randomly assigned into intervention- (n = 16) or control group (n = 15) (Fig. 1). The procedures as well as any possible risks of participating were explained to all subjects before the start of the study both oral and by written information. Written consent for participation was obtained in accordance with research ethics guidelines.
Demographic and physical characteristics assessments
To describe demographic and physical characteristics of subjects, self-reported level of physical activity and daily time sedentary, Body Pain Diagram and The Neck Disability Index was assessed at baseline for all subjects.
Physical activity
To assess self-reported level of physical exercise, physical activity (per week), and sedentary time (per day), indicator issues from The National Board of Health and Welfare were used [24]. The level of physical exercise was measured in minutes per week on a six-graded scale; 0 min, less than 30 min, 30–60 min, 60–90 min, 90–120 min, and more than 120 min. Physical exercise refers to activity that contributes to shortness of breath, such as running, gymnastics or ball sports. Level of physical activity was measured in minutes per week on a seven-graded scale; 0 min, less than 30 min, 30–60 min, 60–90 min, 90–150 min, 150–300 min, and more than 300 min. Physical activity refers to low intensity activities such as walking, cycling or gardening. Sedentary time was measured in hours per day on seven-graded scale; never, 1–3 h, 4–6 h, 7–9 h, 10–12 h, 13–15 h, almost all day. Sedentary time refers to the time spent on resting/sitting during a normal day (apart from sleep).
Body pain diagram
A Body Pain Diagram (BPD) [25] was used to examine the location of pain. On the BPD, the body was divided into 18 different areas. For each area, the subjects were asked to score how often they perceived pain on a 6-point scale where 0 = never and 6 = almost every day.
Neck disability index
The Neck Disability Index (NDI) [26] was used to indicate to which extent the pain affects subjects in their daily life. The NDI consists of ten sections with five statements scored from 0 to 5 (0 = no pain, 5 = worst pain imaginable). A total score on the NDI is calculated by adding up the points from all ten sections (maximum 50 points) [26]. From the total amount of points, score disability level is rated as follows: 0–4 = No disability; 5–14 = Mild disability; 15–24 = Moderate disability; 25–34 = Severe disability; 35–50 = Completely disabled.
Testing procedure and randomization
First subjects’ age, gender, height and weight were collected. Next, the subjects filled out a questionnaire including both demographic information as well as a Numeric Rating Scale (NRS) [22], Body Pain Diagram (BPD) [25] and Neck Disability Index (NDI) [26]. The test managers were available if any uncertainties about the questionnaire occurred. When the questionnaire was completed a six-minute computer work session, including photographing of the habitual sitting posture in the sagittal plane, was performed. Both measurement occasions followed the same test protocol and was performed in a secluded room. The subjects were informed if they had been randomized into intervention- or control group when the test protocol was completed at the first measurement occasion. Simple randomization was used for group allocation where each subject chose a sealed note in which one of the words “intervention” or “control” was written. One of the researcher carried the randomization. The intervention group got instructions about the BBT treatment schedule and the application procedure. The first set of BBT was applied by the test managers on subjects’ shoulder and lower back before a mobile photograph was taken and sent to the subject to have as a reference for upcoming applications at home. Both groups were informed to not take any kind of treatment such as massage or chiropractic during the study.
Outcome measures
Numeric rating scale
The primary outcome measure was pain which was assessed by the Numeric rating scale (NRS) [23]. The subjects were asked to assess their intensity of pain in neck, shoulders or back during the last week. To be considered a clinically relevant change in pain intensity level between baseline and follow-up measurement, at least a two-point change on the NRS was needed. This has been shown to be the minimal clinically important difference (MCID) [23].
Photographic posture analysis method
Secondary outcome measure was forward head posture. Using the Photographic Posture Analysis Method (PPAM) to evaluate sitting posture is considered a valid and reliable method [27]. The craniovertebral (CV) angle was assessed from photographs of the habitual sitting posture taken in the sagittal plane at starting position and then every 2 min during a 6-min computer task in a simulated computer workstation [19, 27]. For each subject, preparations consisted of positioning anatomical markers, using coach tape, on the spinous process of the seventh cervical vertebra (C7). The starting position was standardized following a protocol described by Falla et al. [19]. Subjects were placed in an upright position defined as “a vertical pelvic position (no anterior or posterior pelvic tilt) and with the assumption of a lumbar lordosis and thoracic kyphosis” [19]. Subjects had their feet flat on the floor and the knees in 90 degrees of flexion with arms hanging relaxed by the side. During the 6-min computer task, subjects were instructed to play the game Klondike Solitaire, using their dominant hand and have the other hand rested on the desk. They were instructed to work in their natural work-position [3]. The subject was instructed not to cross the thighs or move the chair until the test manager interrupted the session. The simulated workstation consisted of a 72 cm high table, where a 14″ laptop was placed 11 cm from the table edge. A non-adjustable chair (height 45 cm, seat depth 40 cm) was used. The front edge of the chair was placed in line with the table edge. A high definition mobile camera (Huawei P10 Leica Summarit-H 1:2.2/27 ASPH, Huawei Technologies Co., Longgang District, Shenzhen, China) was mounted 90 cm from the floor on tripods placed 1,2 m away from the subjects’ chair and all anatomical markers were visible in one image. The Android application ‘Silent Camera’ and a Bluetooth remote control (Holdit Remote Shutter) were used while taking the photographs so that the test manager could sit further away from the subject than 1.2 m. The digital clock on the computer, and in the game, were covered with white sport tape so as not to distract the subject. The same equipment was used for all measurements and tape-markers on the floor made sure that the equipment was placed in the same way during all measurements. All photographs were taken from the subjects’ right side. The postural analysis was performed using the free software Kinovea (version 0.8.15, Creative Commons Attribution 3.0). On each picture (taken minute 0, 2, 4, 6), 190% digital zoom was applicated. A digital marker was positioned on the anatomical markers on vertebrae C7 and on the tragus of the ear, before a horizontal line were drawn through the C7-marker (Fig. 2) [6]. Another line was drawn through C7 and tragus. The CV angle was measured in degrees ( ̊) between the two lines. The same measurement procedure was done with each picture (minute 0, 2, 4, 6). CV angle during minute 0–6 were measured and expressed in absolute degrees and a mean value of the CV angle during minute 2–6 was calculated.
Intervention
Balance body tape-treatment
BBT is waterproof, latex free, made of 100% cotton and is attached to the body with non- toxic glue [16]. The study included posture taping during a 19-day treatment period with posture- and lower back BBT. The lower back taping was performed on the grounds that it would capture an ideal alignment in the sagittal plane [1]. Follow up- measurement was accomplished 22 days from baseline measurement and treatment initiation. The treatment protocol was 72 h with BBT applicated on shoulders and lower back which were followed by 24 h of rest before a new set of BBT were applicated for another 72 h [16]. This procedure was repeated with five sets of BBT.
The test managers accomplished the first application of BBT, during the first measurement occasion, after the subjects’ baseline measurements were completed. The four remaining applications were completed at home, following an individual schedule and with assistant help. Subjects were instructed to perform the application about the same time (+/− 2 h) each time and to make sure that all four applications were carried out at the day and time instructed. Application instructions, both verbal and written, were provided at the first measurement occasion and the test managers were available to answer questions on email and phone during the whole intervention.
Application procedure: The application started by cleansing the skin and, if necessary, removing hair growth in order for the tape to sit well. The protective paper was removed and both tops were applied just below the neck hair. Then, one side of the protective paper was removed and the tape was attached in the order; neck, shoulders and thoracic spine. For the lower back the tape was attached from top to bottom. To ensure that the glue adheres properly, the tape was rubbed by hand. The head was kept in a neutral position throughout the application procedure.
Statistical analyses
The analysis was performed using Microsoft Excel and IBM SPSS (IBM SPSS Statistics for Windows, Version 24.0. IBM, Armonk, New York, USA). The level of significance was determined to p < 0.05. Due to the relatively small sample size and the qualitative nature of the NRS (ordinal data), non-parametric tests were used. The Spearman’s rank-order correlation was used to examine the correlation between score on NRS and the CV angle. The correlation coefficient (rs) were categorized as follows: 0.00–0.19 Very weak, 0.20–0.39 Weak, 0.40–0.59 Moderate, 0.60–0.79 Strong and 0.80–1.00 Very strong [3]. Wilcoxon’s signed rank test was used to assess differences in NRS and CV angle before and after the treatment period, within the groups. Mann-Whitney U test was used to assess differences between intervention- and control group before and after the intervention. The change in score before and after the intervention was also compared to the minimal clinically important difference (MCID = 2) [23]. The number of subjects was established on sample size calculation with the NRS as the primary outcome measure. Based on a power of 0.90 (α =0.05), approximately 13 subjects would be required, in each group (intervention and control, respectively), to detect a minimal clinical relevant difference change in pain intensity level of at least a two-point change on the NRS between groups. Therefore, this study was planned to recruit a minimum of 30 subjects with regard for potential dropouts. Allowing a drop-out rate of about 15%, 16 subjects in the intervention group and 15 in the control group were recruited.