Chronic low back pain is a highly prevalent condition with unclear pathological underpinnings for majority of the cases. Lack of a mechanistic understanding of the exaggerated pain experience can negatively affect treatment strategies. Over time, quantitative sensory testing has evolved to extend and elaborate on the differential diagnosis of conditions of sensori-neural origin, including chronic pain conditions. Many studies have attempted to classify patients of chronic low back pain using quantitative sensory testing but there are is no protocol or modality that has been standardised to assess the same. A case-control study was designed to test the degree of sensitisation in patients of chronic low back pain in a hospital setting. Gradient of thermal stimuli at the local site (low back region) and the distant site (hand) using method of limits. Series of two-group comparisons were done to compare the study groups. Compared to the pain-free volunteers, patients of chronic low back pain homogenously displayed hyperalgesia at the local and the distant site suggesting widespread sensitisation. Thus, the present study presents a simple and effective quantitative sensory test to capture the ambiguities of sensory changes in chronic low back pain.

Keywords: Chronic low back pain; Quantitative sensory testing; Hyperalgesia; Allodynia; Thermal pain.

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Dr Renu Bhatia, MD

Additional Professor, Department of Physiology

Lab Incharge: Pain Research and TMS Laboratory

All India Institute of Medical Sciences, New Delhi, India, Pin code: 110024