Changes in Radicular Pain and Pain Modulation
Condition: Back Pain; Back Pain With Radiation
MeSH terms: Back Pain
Study type: Interventional

Summary: 
      The objectives of this study are: 1)To investigate the difference in pain modulatory
      mechanisms using quantitative sensory testing (QST) between healthy controls and patients
      with radicular leg pain due to nerve root compression. 2) To investigate the association
      between changes in radiating leg pain and pain modulation among the patient group.
    

Detailed description: 
      Few studies have investigated pain modulatory mechanisms using QST in patients with lumbar
      radiculopathy due to nerve root compression. Knowledge about the association between changes
      in the experience of pain and changes measures of pain modulation is to our knowledge
      limited. The results could potentially contribute to knowledge about mechanisms involved in
      lumbar radiculopathy and facilitate future studies. The hypotheses of the study are: 1)
      Measures of pain modulation will be less efficient among patients with lumbar radiculopathy
      showing reduced pain inhibition and facilitated temporal summation compared to healthy
      controls. 2) Improvements in pain modulation will be associated with improvements in clinical
      pain outcomes
    

Intervention name(s): Pressure pain assessment using computer controlled cuff algometry; Temporal summation (TS); Conditioned pain modulation (CPM); Low back pain rating scale (LBPRS-pain); Oswestry Disability Index
Intervention type(s): Diagnostic Test; Diagnostic Test; Diagnostic Test; Diagnostic Test; Diagnostic Test
Intervention description(s): Pressure pain sensitivity is assessed. The pressure is gradually increased and pain is rated by the participant on an electronic visual analogue pain rating scale (VAS) which is connected to the equipment. The assessment is performed on the lower leg and the upper arm. The pain free leg and the left upper arm is used in the patient group. The leg used in the control group will be chosen in a balanced manner meaning that half will receive pressure on the left leg and the other half on the right leg. The pain detection threshold (PDT), pain pressure tolerance threshold (PPT) and pressure pain intensity perceived as 6 on the VAS (VAS6) at the leg site is registered. The PDT and PPT on the arm site is registered.; 10 repeated inflations on the lower leg with a 1 sec interval. The pressure used at each pressure is equivalent the PPT measured at baseline. Each inflation is rated on the VAS. TS is registered as the increase pain intensity.; The cuff on the upper arm is inflated until 70% of the PPT is reached. While the pressure on the arm is kept constant the cuff on the leg is inflated. PDT, PPT and VAS6 pressure at the leg site is registered during the tonic stimulation (pressure on the left arm). The procedure on the leg is repeated within 30 seconds after the pressure is released on the arm site.; A questionnaire measuring the intensities of low back pain and leg pain currently, on average the last two weeks and the worst pain within the same period.; A questionnaire measuring the disability in relation to low back pain and leg pain.
Other intervention name(s): Assessment of pain sensitivity; Repeated pressure pain; Pain inhibition; Pain intensity; Disability
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Intervention model description: The study has a cohort design and will include a patient group (male and female) attending a treatment program at the Spine Centre of Southern Denmark and an equally large control group matched on age and gender.
Masking: Single (Participant)
Primary purpose: Basic Science
Keywords: low back pain; radiculopathy; conditioned pain modulation; temporal summation