[Preoperative, neuropathic component in patients with back pain]. / Präoperative, neuropathische Komponente bei Rückenschmerzen.

BACKGROUND: The objectification of pain is essential for evaluation, treatment plan and follow-up; therefore, it is necessary to find reliable clinical parameters. OBJECTIVE: The goal of the study was the preoperative screening of a neuropathic component in patients with vertebral compression fracture (WKF), herniated disc (NPP) or spinal cord compression (SKS). MATERIAL AND METHODS: Depending on the preoperative condition on admittance, patients were classified into three groups: group 1 WKF, group 2 NPP and group 3 SKS. To characterize the pain we used the painDETECT questionnaire, the Oswestry questionnaire and further questionnaires. All patients were surgically treated according to the diagnosis, e.g. radiofrequency kyphoplasty, nucleotomy or spondylodesis. RESULTS: We evaluated the data from 139 patients (45% WKF, 34% NPP and 21% SKS). There were no differences in preoperative pain intensity (median ordinal scale 0-10) with a mean preoperative score of 7 for all groups. The total score of the painDETECT questionnaire showed significantly higher results in group 2 (median 18) and in group 3 (median 14) than in group 1 (median 9). There was even a significant difference between groups 2 and 3 (p = 0.03). The highest pain intensity was detected in group 1 with a median visual analog scale (VAS) of 71 mm. The total scores in the painDETECT questionnaire and the scores in the Oswestry questionnaire correlated in groups 2 and 3. CONCLUSION: The painDETECT questionnaire was shown to be a very suitable instrument for evaluating the neuropathic pain component in patients with dorsalgia. This could be very useful in planning further therapy.

Diagnosis of Neuropathic Components in Patients with Back Pain Before and After Surgery.

Background: The perception of back pain subjective is hard for physicians to measure. For this reason, questionnaires are an important instrument to evaluate the pain 1. The main point of this study was to verify differentiation of pain symptoms in patients with different pain mechanisms. The most important parameter was the PainDetect questionnaire, which can differentiate between nociceptive and neuropathic pain. Additional parameters were measured before and after surgery to characterise pain symptoms in detail. Material and Methods: We selected patients with diagnosed vertebral compression fracture, herniated disc or with spinal cord compression. To characterise the preoperative condition on admittance, we collected the data from the physical examination, as well as clinical data, including X-ray, CT and MRI. To characterise the pain, we used the painDetect questionnaire, the Oswestry Index questionnaire (ODI) and the visual analogue scale (VAS). Depending on the diagnosis, patients were treated by surgery (radiofrequency kyphoplasty, nucleotomy, spondylodesis). At 2 to 3 days and 6 months after surgery, we repeated the questionnaire and compared the results with those before the operation. Data on patient satisfaction and adverse events were also collected. Results: This study included 62 patients with vertebral compression fracture (group 1: VBF, 89 % female, mean age 71 years) and 77 patients with herniated disc or spinal cord compression (group 2: non-VBF, 55 % female, mean age 53 years). There was no difference between both groups in preoperative pain intensity (acute, maximum, average): median ordinal scale 0 to 10; group 1: 6, 8, 7; group 2: 6, 9, 7. The total score in the painDetect questionnaire differed significantly between the two groups (median group 1 = 9, group 2 = 17; effect size r = 0.5; p = 0.000). The existence of neuropathic pain was presumed (> 90 %) in 3 % of the patients in group 1 and in 13 % of patients it was not excluded. In contrast, in group 2 it was presumed (> 90 %) in 43 % of patients and in 30 % of patients it could not be excluded. Patients with vertebral compression fracture had greater pain intensity (VAS 71) than patients from group 2 (VAS 53). There was no difference in the total score of the Oswestry questionnaire between the two groups (56 % vs. 58 %). Pain intensity was significantly reduced in both groups after the operations. Six months postoperatively, pain intensity (median ordinal scale 0 to 10; acute, maximum, average) was 2, 5, 3 in group 1 and 2, 4, 2 in group 2. Moreover, the final scores of the painDetect questionnaires were significantly lower in both groups after the operations (4 in both groups). The median score of the ODI was reduced in both groups, with an effect size of 0.6. 98 % of the patients in group 1 and 94 % in group 2 were satisfied with the outcome of the operation. Conclusion: The preoperative pain characteristics of patients with vertebral compression fracture is different from those of patients with herniated disc or with spinal cord compression. 43 % of patients in group 2 exhibited a neuropathic pain component and in 30 % this could not be excluded. In contrast, in group 1 only 3 % of the patients exhibited a neuropathic pain component. Postoperatively, pain symptoms were significant reduced in both groups, so that the risk of chronic pain was considerably less.