Reorganization in Secondary Somatosensory Cortex in Chronic Low Back Pain Patients

Abstract

STUDY DESIGN: A cross-sectional comparative study between chronic low back pain (CLBP) patients and healthy control subjects. OBJECTIVE: The aim of this study was to investigate reorganization in the sensory cortex by comparing cortical activity due to mechanosensory stimulation of the lumbar spine in CLBP patients versus a control group by using functional magnetic resonance imaging (fMRI). SUMMARY OF BACKGROUND DATA: LBP is now the number 1 condition across the world in terms of years living with a disability. There is growing evidence that maladaptive changes in the processing of sensory input by the central nervous system are central to understanding chronic (back) pain. METHODS: Nonpainful, posterior-anterior (PA) movement pressure was applied manually to lumbar vertebrae at L1, L3, and L5 in 13 healthy subjects and 13 CLBP patients. The manual pressure (30 N) was monitored and controlled using sensors. A randomized stimulation protocol was used consisting of 51 pressure stimuli of 5 seconds duration. fMRI data analysis was performed for the group activation within the primary and secondary sensory cortices (S1 and S2, respectively) and the representation of the individual vertebrae was extracted and statistically analyzed. RESULTS: Nonpainful PA pressure revealed no cortical reorganization in S1. In contrast, the extent of S2 activation in the CLBP group was significantly reduced in both hemispheres. In the control group, a somatotopy was identified for the lumbar vertebrae between L1 and L3, respectively, and L5 in S2 of the right hemisphere. Most importantly, a blurring of the somatotopic representation of the lumbar spine in S2 was observed in the patient group. CONCLUSION: Together, these maladaptive changes suggest a reorganization of higher-order processing for sensory information in CLBP patients that might have implications for a decreased sensory acuity, also related to body perception and subsequent altered functioning of the lumbar spine. LEVEL OF EVIDENCE: 2. Study Design. A cross-sectional comparative study between chronic low back pain (CLBP) patients and healthy control subjects.Objective. The aim of this study was to investigate reorganization in the sensory cortex by comparing cortical activity due to mechanosensory stimulation of the lumbar spine in CLBP patients versus a control group by using functional magnetic resonance imaging (fMRI). Summary of Background Data. LBP is now the number 1 condition across the world in terms of years living with a disability. There is growing evidence that maladaptive changes in the processing of sensory input by the central nervous system are central to understanding chronic (back) pain. Methods. Nonpainful, posterior-anterior (PA) movement pressure was applied manually to lumbar vertebrae at L1, L3, and L5 in 13 healthy subjects and 13 CLBP patients. The manual pressure (30 N) was monitored and controlled using sensors. A randomized stimulation protocol was used consisting of 51 pressure stimuli of 5 seconds duration. fMRI data analysis was ...

Explicit and Implicit Own's Body and Space Perception in Painful Musculoskeletal Disorders and Rheumatic Diseases: A Systematic Scoping Review

“…In particular, sensory representations and somatosensations were often used in literature as a surrogate for perceptual representations and somatoperception, mainly to describe their associated dysfunctions. Readers are invited to see Flor et al (1997), Flor (2003), and Hotz-Boendermaker et al (2016) for maladaptive reorganizations of somatosensory representations, and Tsay et al (2015) for a comprehensive review on somatosensations. Moreover, we have deliberately avoided the use of the umbrella term "body image" given the controversies and interpretational difficulties with this term (de Vignemont, 2010;Pitron et al, 2018;Gadsby, 2019): it has often been used as a "passepartout" term, lumping together phenomena and psychological capacities quite different from each other, often referred to beliefs and affective attitudes related to the body (Mohr et al, 2010).…”

The translation, validity and reliability of the German version of the Fremantle Back Awareness Questionnaire

“…Early work by Flor et al [ 6 ] using brain imaging identified somatosensory disorganization in patients with chronic low back pain (CLBP). More recent imaging studies in people with CLBP have shown structural and functional alterations in cortical and subcortical areas, associated with the processing of sensory information [ 7 – 9 ].…”

Disrupted body-image and pregnancy-related lumbopelvic pain. A preliminary investigation

“…For low back pain (LBP) in general there has been recent interest in the role that altered body-image that is, the way the body feels to the individual [14], might play in the pain experience [14][15][16]. There is evidence of reorganisation [17][18][19][20][21][22] as well as morphological [23][24][25][26][27][28][29][30] and biochemical changes [31,32] in areas of the brain thought to subserve body-image. Several studies have reported that people with LBP perceive the back as fragile and vulnerable [33][34][35], feel a sense of alienation and rejection of the back [36][37][38], represent the back differently when asked to draw how the back feels to them [39,40] and endorse questionnaire items associated with altered perceptual awareness of the back [16,41,42].…”