On the assessment of nerve involvement and of dysfunction in patients with spinal pain

Abstract

Nerve involvement originating in the spine can cause pain and/or organ dysfunction. Reliable and valid assessment of nerve involvement is a prime diagnostic task as it may require other than symptomatic treatment.

The aim of this thesis was to analyse the reliability of, and association between, some diagnostic methods and classifications used in the assessment of patients with spinal pain. In particular the reliability of, and association between, methods used to detect nerve involvement originating in the spine.

Material: Articles I and II are based on study A where 100 consecutive primary health care patients with neck- and/or shoulder discomfort were assessed by 2 independent examiners using a simplified pain drawing, patient history and a physical exam with 66 clinical tests focused on neurology. Article III is based on study B on 50 consecutive outpatients with low back pain (LBP), assessed by 2 independent examiners using patient history and a physical exam with 30 clinical tests. Article IV is based on study C on 61 consecutive patients referred to magnetic resonance imaging (MRI) of the lumbar spine where we used the simplified pain drawing, patient history and a physical exam focused on neurology to detect nerve involvement originating in the spine.

Results: In study A inter-examiner reliability was less than acceptable for many tests. Only a bimanual sensibility test with spurs reached K > 0.6 indicating good reliability and no bias. With known history, prevalence of positive findings increased but not reliability. Four out of five patients had, in the region of discomfort, 2 or more clinical test findings indicating nerve involvement originating in the spine. Interexaminer reliability based on a first impression assessment of the pain drawing reached 88% overall agreement and a sensitivity of 90 % to the final assessment. Two thirds of the patients added symptoms to the pain drawing during history session.

In study B excellent inter-examiner reliability (K > 0.8) was found for using Kirkaldy-Willis Classification of LBP. Radiological findings had no impact. Good inter-examiner reliability was found for straight leg raise, movement range and sensibility testing with spurs. In study C we found that MRI visible nerve involvement significantly underestimated the high percentage of nerve involvement detected in the physical exam and in the pain drawing.

Conclusions: Nerve involvement can be detected reliably, simply and quickly with a bimanual sensibility test with spurs and a pain drawing. MRI visible nerve involvement in the lumbar spine underestimates presence of nerve involvement detected in a physical exam and a pain drawing. Nerve involvement in both the cervical and lumbar spine may be a greatly underestimated cause of pain and/or organ dysfunction. This may explain part of today s poor treatment outcome of spinal pain and should encourage further studies on diagnostics and treatment of nerve involvement originating in the spine.