The main objective of the study was to assess the impact of deep tissue massage on subjective and objective parameters in a group of office workers with chronic low back pain.

Specific objectives:

• Assessment of the impact of deep tissue massage on the level of pain
• Assessment of the impact of deep tissue massage on the level of disability
• Assessment of the impact of deep tissue massage on the mobility of the lumbar spine
• Assessment of the effect of deep tissue massage on the discomfort threshold of tissue compression in the area of the erector spinae muscle
• Assessment of the impact of deep tissue massage on the biophysical parameters of the soft tissues of the erector spinae muscle
• Evaluation of the impact of deep tissue massage on the bioelectric potentials of the erector spinae muscle during everyday activities and the flexion-relaxation test

Hypotheses:

• Deep tissue massage will reduce the level of pain in the lumbar spine
• Deep tissue massage will reduce the level of disability
• Deep tissue massage will increase the range of motion of the lumbar spine in all directions
• Deep tissue massage will reduce the threshold of discomfort when compressing the soft tissues of the erector spinae muscle
• Deep tissue massage will reduce muscle tone and stiffness and increase the elasticity of the back extensor muscle
• Deep tissue massage will increase the bioelectrical potentials of the erector spinae muscle while performing tests of activities of daily living
• Deep tissue massage will reduce the value of the flexion-relaxation test

Deep tissue massage is a manual action of the therapist in the superficial and deep layers of muscles and fascia in order to relax, change abnormal patterns, eliminate tension and pain in a maximally ergonomic way. Deep tissue massage should be described as an independent method of therapy using a specific set of techniques and principles. It is a safe method with a wide range of applications, while the techniques themselves can be modified to the needs of the patient. It is believed that deep tissue massage causes: improvement of tissue blood supply, reduction of muscle tension, stretching of muscles and fascia, improvement of muscle and joint function.

Participants A total of 40 patients (30 to 60 years of age) participated in the study. All participants were characterized by the presence of chronic low back pain syndrome, performed office work for 8 hours a day and were characterized by moderate physical activity. Using randomization, participants were divided into two groups (experimental and control). The experimental group included participants who received deep tissue massage (N=20, 18 women and 2 men, average age: 40). The control group included participants who did not receive therapy (N=20, 13 women and 7 men, average age: 43).

Intervention The deep tissue massage lasted 45 minutes. The entire therapy included 4 treatments over a period of 2 weeks. The interval between treatments was 3 days. The conducted therapy included techniques for: quadratus lumborum muscle, erector spinae muscle, thoracolumbar fascia, iliopsoas muscle. All techniques were performed on both sides of the patient's body.

Research methods

The following measurement equipment was used to collect the data:

1. Electrogoniometer. Penny & Giles strain gauge electrogoniometer with two sensors (SG150 - two-axis, Q110 - single-axis). Measurements were taken in a standing position, in accordance with the measurement methodology according to Lewandowsky. All movements of the lumbar spine (forward bending, backward bending, right bending, left bending, right rotation, left rotation) were examined. The average of the three measurements was the result of movability for a given direction. The sensors were attached to the skin using Biometrics double-sided tape. The upper sensor was placed on the Th12 spinous process (lower edge of the sensor), while the lower sensor was mounted on the base of the sacrum (upper edge).
2. Algometer. The Wagner Instruments algometer was used to assess the subjective parameter, i.e. the first discomfort threshold. In the study, the measurement site was the point located on the longissimus muscle, which is a component of the erector spinae muscle. The subjects lay in front. The pressure, detected by the algometer sensor, was applied from above and perpendicularly to the examined muscle (two fingers laterally from the L1 spinous process). Three measurements were made alternately for both sides of the examined muscle. From these measurements, mean values were calculated, which were the results for the right and left sides of the examined muscle.
3. MyotonPRO. In order to study the biophysical parameters of soft tissues, i.e. muscle tone (F) [Hz], stiffness (S) [N/m] and elasticity (D) [no units], the MyotonPRO apparatus was used. During the measurements, the tested person lay on his front. Measurements were made on the longissimus muscle (2 fingers lateral to the L1 spinous process). The pattern composer was programmed as follows: tapping time: 15 ms, interval: 0.8 s, mode: multiscan (5 repetitions). Measurements were made on the right and left muscles.
4. Kinesiologic electromyography (EMG). Kinesiologic electromyography was carried out with an 8-channel electromyographic system with plate electrodes (model W4X8, Biometrics Ltd). The results were recorded using DataLog Bluetooth V7.5 software (Biometrics Ltd). During the examination, six multiple-use surface electrodes (type SX230 1000) were attached with an adhesive tape, after removal of body hair froma 2 cm x 1 cm area of intact skin, disinfection of electrode surface, and wiping the skin a few times with salicylic alcohol to reduce its resistance. The reference electrode (type R230, Biometrics Ltd) was fixed at the distal end of the radius (Lister's tubercle region) with an elastic band. The examination involved lumbar segment of the longissimus muscle, iliocostalis and multifidus (both right- and left-sided bundles). The electrodes were placed according to the international guidelines published by SENIAM. The examination was painless and noninvasive and did not require subject's exposure to any additional electric stimulation. The measurement was preceded by a 10-min warm-up of the keymuscle groups. The list of determined electromyographic parameters included the amplitude of bioelectrical signal from the longissimus, iliocostalis and multifidus muscles, expressed in microvolt. Avoiding a confounding effect associated with measurement conditions, the results were normalized to a reference Maximum Voluntary Contraction (MVC) and expressed in percent. After fixation of the electrodes and preparation of the system, MVC of the longissimus, iliocostalis and multifidus were determined according to the international SENIAM guidelines. The examination started with the subject lying down in a prone position, with arms crossed under the chin, and extended legs. The EMG recordings were obtained during three active extensions of the spine, each lasting 3 seconds, with 30-second intervals in between. MVCs , corresponding to 100% neuromuscular activation of the muscles, was calculated as the mean amplitude for the three repetitions (for each muscle). At the beginning, the Flexion-Relaxation (FR) test was performed. The participant performed forward flexion of the spine and hung freely in this position for 10 seconds. During this test, the participant was asked to be as relaxed as possible. Then the participant was tested during successive tests of activities of daily living: getting up from a chair, sitting on it, lifting and lowering a 1 kg and 2 kg weight. Each test was run at an individually adjusted pace and consisted of three repetitions with 30-second rests between them. The test started at the investigator's request. While lifting and lowering the weights, the subjects kept a straight back, and each hold of the weight lasted 3 seconds and was performed on straight elbows. The result of each test is presented as the mean amplitude for three repetitions for each muscle. The results were normalized to the MVC to assess the degree of muscle involvement during various activities (standing up, sitting down, raising and lowering the roller) in relation to maximal neuromuscular activation. To ensure accurate results, the correct attachment of each electrode was rechecked before each repetition.
5. Revised Oswestry Pain Questionnaire (ODI). The degree of LBP imposed limitations in activity of daily ling (ADLs) was determined with Revised Oswestry Pain Questionnaire, also referred to as Oswestry Disability Index (ODI). The survey consisted of 10 questions, each with 6 possible responses scored from 0 to 5 points. If the respondent chose more than one answer to a given question, the one with higher score was recorded and subjected to the analysis. Maximum overall score amounted to 50 points, which corresponded to 100% disability due to lumbar pain.
6. Roland-Morris Disability Questionnaire (RMDQ). The instrument consists of 24 statements about pain and its influence on ADLs. The respondent chooses only the statements that refer to his/her ailments. Maximum overall score may vary between 0 and 24 points.
7. Visual-Analog Scale (VAS). This subjective tool is used to assess the level of pain. The participant marks the level of pain on a 10 cm scale, where 0 is no pain and 10 is the maximum pain he has ever felt.

In order to assess the impact of deep tissue massage therapy on the study population, two measurements were made over time: before and after therapy.

Ethics All measurement methods used were non-invasive and safe for health. The study was approved by the local Bioethics Committee. Each participant had the right to withdraw from the study at any stage. All collected data is anonymous and will be used only to conduct statistical analyzes for scientific purposes.

Inclusion Criteria:

• Chronic Low-Back Pain
• office worker

Exclusion Criteria:

• spine surgeries
• cauda equina syndrome
• cancer
• pain or motor and sensory deficits in the lower extremities below the level of the knee
• various therapies to treat chronic low-back pain

University IPD sharing platform is under preparation. All data will also be available to researchers via the principal researcher's email (wendt@awf.poznan.pl) or Research Gate website.

Data will be available from May/June 2023.

Available to all researchers.

Triple (participant, researcher, outcome assessor). Participants did not know which study group they belonged to. Each participant drew a number that was characteristic of a given research group (experimental DTM group or control group). The researcher also did not know which group the participant belonged to (he only used the participant number). Outcome assessor did not know which group was experimental and which was control (they were marked with numbers instead of names). The coordinator supervised the proper course of the study.