Primary
The overall score of the DASH (Disability of Arm Shoulder and Hand) questionnaire – Dutch language version will be used as the primary outcome measure. The DASH is a multidimensional (physical, emotional and social) 30-item self-report measure focussing on physical function pain and other symptoms. At least 27 of the 30 items must be completed for a score to be calculated. The assigned values for all completed responses are simply summed and averaged. This value is then transformed to a score out of 100 by subtracting one and multiplying by 25. The transformation is done to make the score easier to compare to other measures using a 0–100 scale. A higher score indicates greater disability.
where n is equal to the number of completed responses.
Scoring is on a 5-point Likert scale from no difficulty (0 points) to very difficult (5 points). The range of the total score is from 0 to 100, where 0 means no symptoms (pain, tingling, weakness or stiffness) and no difficulty in performing daily activities, while 100 means extreme, severe symptoms and unable to perform any daily activity. Content and face validity of the DASH were confirmed by a variety of experts of the American Academy of Orthopaedic Surgeons (AAOS), the council of Musculoskeletal Speciality Societies (COMSS) and the institute for Work and Health (Toronto, Ontario, Canada) throughout the development process [
44].
Its internal consistency was excellent (Cronbach's alpha = 0.96) during field-testing. The test-retest reliability was excellent (ICC
2.1 = 0.92 and 0.96) in two studies [
45,
46] and satisfactory in one study (Pearson 0.98 and kappa 0.67). The minimal detectable Change (MDC) was calculated in a population of 172 patients with several upper limb disorders (Osteoarthritis, Carpal Tunnel syndrome, Rotator Cuff syndrome, Rheumatoid Arthritis and Tennis Elbow) [
47]. The Minimal Detectable Change (MDC) varied between 10.70 (at 90% confidence level) and 12.75 (at 95% confidence level). The DASH demonstrated to be a responsive questionnaire.
The inter- and intra-observer reliability is good to excellent (intra-observer reliability Pearson r = 0.96 to 0.98; ICC = 0.91 to 0.96; Inter-observer agreement Cohen's kappa = 0.79).
The construct validity was estimated by comparing the DASH to several other questionnaires. The correlation with other instruments like the SPADI (Shoulder Pain and Disability Index) is good (Pearson's r = 0.82 to 0.88). The DASH questionnaire is one of the best among 16 other questionnaires for shoulder symptoms [
48].
Secondary
An independent examiner will perform the following tests.
• The total number of shoulder muscles with MTrPs will be counted and compared to the baseline measurement findings.
• Passive range of motion of the shoulder will be measured by an handheld digital inclinometer (The Saunders group Inc, Chaska, MN). The range of motion of the non-painful shoulder will be used as reference [
49,
49,
50]. Because the normal range of motion differs from one individual to another, we focus on improvement of limited range of motion during the experiment (both experimental group and control group).
◦ For the measurement of passive external rotation, the patient is in a supine position, with the shoulder in 0° of abduction and rotation, the elbow flexed at 90° and the forearm in a neutral position. This position is defined as the position of 0°. The observer then performs external rotation until pain limits the range of motion or the extreme of the range is reached. The inclinometer is placed against the volar side of the forearm. This range of motion is recorded in degrees. The normal range of motion for external rotation is between 70° and 90°.
◦ For the measurement of passive glenohumeral abduction, the patient is seated upright, and the position of 0° is defined as the upper arm is in a neutral position. While palpating the lower angle of the scapula with the thumb, the examiner elevates the upper arm of the patient until the scapula begins to rotate or pain limits further motion. The inclinometer is placed against the lateral side of the upper arm near the elbow. The range of motion is recorded in degrees. The normal range of motion is 90°.
◦ For the measurement of passive elevation (through flexion), the patient is in the supine position with the arm along the side. This position is defined as the position of 0°. The observer than performs elevation until pain limits the range of motion or the extreme of the range is reached. Then the inclinometer is placed against the medial side of the upper arm near the elbow. The range of motion is recorded in degrees. The normal range of motion is between 165° and 180°
◦ For the measurement of internal rotation the patient is in a prone position. The shoulder is 90° abduction, and the forearm is in neutral position. This position is defined as the position of 0°. The observer than performs internal rotation until pain limits the range of motion or the extreme of the range is reached. The sensor is placed against the volar side of the forearm. The normal range of motion is 70°
◦ For the measurement of horizontal adduction the patient is in a supine position. The arm is in 90° abduction. This position is defined as the position of 0°. The observer performs adduction, while the arm stays in the vertical plane, until pain limits the range of motion or the extreme of the range is reached. The normal range of motion is 135°
• Finally the total number of treatment sessions will be counted. This is done by an assistant, who is not involved in the study by using the administration-software of the practice [see Table
1].
Table 1
Overview of variables
Age* | X | | | Interview |
Gender* | X | | | Interview |
Work
| X | | | Interview |
Dominant side affected
| X | | | Interview |
Duration of the complaints* | X | | | Interview |
DASH DLV | X | X | X | Questionnaire |
Use of medication
| X | X | X | Interview |
Use of other therapy
| X | X | X | Interview |
Work% | X | X | X | Interview |
Improvement(percentage of perceived improvement) | | X | X | Interview |
Number of involved muscles
| X | X | X | Assessment |
No. of treatment sessions
| | | X | Assessment |
Health status for baseline comparison | X | | | RAND-36 DLV |
Existence and severity of symptoms of depression
| X | | | Beck Depression Inventory |
Shoulder Passive ROM
| X | X | X | Goniometry |
• flexion | X | X | X | |
• abduction | X | X | X | |
• external rotation | X | X | X | |
• internal rotation | X | X | X | |
• cross body adduction | X | X | X | |