Changes of Pain and Functional Parameters in Back Pain Patients Over Time

Primary outcomes

1. Changes in Visual Analog Scale Pain Scores

   Time frame: Baseline, 6 weeks, 6 months

   Changes in pain were assessed using a unidimensional 10-cm Visual Analogue Scale. The scale ranged from one endpoint depicting a happy face, indicating "no pain," to the other endpoint depicting a sad face, indicating "worst possible pain." The distance in centimeters from the low end (0) of the VAS to the patient's mark was used as a numerical measure of pain severity. The lowest score was 0, indicating no pain, the maximum score 10, indicating worst possible pain. Higher scores indicate more severe pain.

2. Changes in Visual Analog Scale Ratings of Numbness

   Time frame: Baseline, 6 weeks, 6 months

   Changes in pain were assessed using a unidimensional 10-cm Visual Analogue Scale. The scale ranged from one endpoint depicting a happy face, indicating "no numbness," to the other endpoint depicting a sad face, indicating "worst possible numbness." The distance in centimeters from the low end of the VAS to the patient's mark was used as a numerical measure of pain severity. The lowest score was 0, indicating no numbness, the maximum score 10, indicating worst possible numbness. Higher scores indicate more severe numbness.

3. Changes in Visual Analog Scale Ratings of Paresthesia

   Time frame: Baseline, 6 weeks, 6 months

   Changes in pain were assessed using a unidimensional 10-cm Visual Analogue Scale. The scale ranged from one endpoint depicting a happy face, indicating "no paresthesia" to the other endpoint depicting a sad face, indicating "worst possible paresthesia." The distance in centimeters from the low end of the VAS to the patient's mark was used as a numerical measure of pain severity. The lowest score was 0, indicating no paresthesia, the maximum score 10, indicating worst possible paresthesia. Higher scores indicate more severe numbness.

4. Changes in Anterior Flexion Measured in Centimeters

   Time frame: Baseline, 6 weeks, 6 months

   The fingertip-to-floor (FTF) test (cm) was used to assess the lumbar maximal anterior flexion. Patients performed maximal flexion up to the pain threshold, keeping the elbows, fingers, and knees straight and the heels together.

5. Changes in Back Extension Measured in Degrees

   Time frame: Baseline, 6 weeks, 6 months

   Extension was measured using a baseline bubble inclinometer. Patients performed maximal extension up to the pain threshold, keeping the elbows, fingers, and knees straight and the heels together.

6. Changes in Lateral Flexion Measured in Centimeters

   Time frame: Baseline, 6 weeks, 6 months

   The fingertip-to-floor (FTF) test (cm) was used to assess the lumbar maximal lateral flexion. Patients performed maximal flexion up to the pain threshold, keeping the elbows, fingers, and knees straight and the heels together. The contralateral hip remained in contact with the treatment table during lateral flexion.

7. Changes in the Maximal Isometric Strength in Newton

   Time frame: Baseline, 6 weeks, 6 months

   Maximal isometric strength was tested using the NOD hand-held dynamometer. An active strength test of the primary innervated muscle was performed for 3 s using a standardized procedure adapted from Mentiplay et al. The patient was instructed to press against the examiner's hand-and thus the hand-held dynamometer-as hard and as long as possible. The dynamometer recorded the strength and duration of the isometric contraction both graphically and numerically.

   The tested muscles included:

   L3: M. quadriceps femoris; L4: M. quadriceps femoris; M. tibialis anterior (TA); L5: M. TA; M. extensor hallucis longus (EHL); S1: M. gastrocnemius; M. triceps surae. Due to the small subgroups, the maximal isometric strengths of the quadriceps femoris muscle and triceps surae muscle were excluded from the analysis.The mean of the two closest of three values (N) was used for further analysis.

8. Changes in Nerve Tension Assessed by the Straight Leg Raising Test, Measured in Degrees

   Time frame: Baseline, 6 weeks, 6 months

   Nerve tension of the affected spinal nerve root was assessed using the straight leg raise pain provocation test. A baseline bubble inclinometer was placed directly above the patella to measure the angle in degrees between the examination table and the elevated limb.

9. Changes in Quality of Life Assessed by the Physical Component Summary of the 36-Item Short Form Health Survey

   Time frame: Baseline, 6 weeks, 6 months

   General health was evaluated using the German version 2.0 of the 36-item Short Form Health Survey (SF-36). The PCS score aggregates four subscales-Physical Functioning, Role Physical, Bodily Pain, and General Health-into a standardized score ranging from 0 to 100, with higher scores reflecting better physical health.

10. Changes in Quality of Life Assessed by the Mental Component Summary of the 36-Item Short Form Health Survey

    Time frame: Baseline, 6 weeks, 6 months

    General health was evaluated using the German version 2.0 of the 36-item Short Form Health Survey (SF-36). The MCS score aggregates four subscales-Vitality, Social Functioning, Role Emotional, and Mental Health-into a standardized score ranging from 0 to 100, with higher scores reflecting better mental health.

11. Changes in Physical Activity Assessed Using the International Physical Activity Questionnairee

    Time frame: Baseline, 6 weeks, 6 months

    Physical activity was assessed using the self-administered short German version of the International Physical Activity Questionnaire (IPAQ) with a "last 7 days recall". Data were processed and analyzed according to the official IPAQ scoring protocol and reported in metabolic equivalents of task minutes per week

12. Changes in Disability According to the Oswestry Disability Index

    Time frame: Baseline, 6 weeks, 6 months

    Disability was assessed using the German version of the Oswestry Disability Index. The ODI consists of 10 sections, each scored from 0 to 5. Scores are summed and expressed as a percentage ranging from 0 to 100, with higher scores indicating greater disability.