Participants with radicular leg pain due to lumbar disc herniation or to foraminal- or recess stenosis.

Baseline assessments of pain intensities are performed through questionnaires prior to protocol. Data regarding initial pain, function, age, gender, pain-duration, weight and height is retrieved from the clinical registry SpineData.

Pain sensitivity, temporal summation and conditioned pain modulation are assessed at the first visit in the treatment program. The protocol is repeated at the last visit in the treatment program.

Healthy controls Healthy age and gender-matched controls. Gender, weight and height are registered on questionnaires prior to protocol.

Pain sensitivity, temporal summation and conditioned pain modulation are assessed at the first visit. The tests are repeated at the next visit. The interval between the two sessions will be determined by the averaged interval between tests in the patient group.

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.

Change in pain sensitivity between baseline and follow-up. Cuff is placed around the lower leg and on the upper arm and gradually inflated (1kPa/sec) on each location separately. In patients, the cuff is placed on the non-painful leg and left upper arm, in healthy controls, half of the participants the cuff is placed on the left leg and half on the right leg, while the other cuff is placed on the left upper arm. First, the pressure needed to evoke an onset of pain (pain detection threshold, PDT), the pressure at pain intensity VAS 6 (Measured on an electronic visual analogue scale: 0=No pain, 10=worst pain imaginable pain) and pain tolerance threshold (PTT) is assessed on the lower leg. Secondly, the PDT and the PTT is assessed on the left upper arm.

Change in pain intensity between baseline and follow-up. Cuff is placed on the lower leg. In patients the non-painful leg is used, in healthy controls, half of the participants will be tested on the left leg and half on the right leg. 10 painful stimuli are performed with a one-second interval in between. After each stimulus, the participant rates the pain intensities using an electronic VAS ( 0=No pain, 10=worst pain imaginable pain). The increase in pain intensity is defined as temporal summation.

Change in pain intensity between baseline and follow-up. Cuff is placed on the lower leg. In patients the non-painful leg is used, in healthy controls, half of the participants will be tested on the left leg and half on the right leg. 10 painful stimuli are performed with a one-second interval in between. After each stimulus, the participant rates the pain intensities using an electronic VAS ( 0=No pain, 10=worst pain imaginable pain). The increase in pain intensity is defined as temporal summation.

Change in pain between post-treatment and pre-treatment. The average pain during the last two weeks, the worst pain experienced during the same period and current pain is rated by the patient. Range 0-30. 0=no pain, 30= Worst pain imaginable.