A novel computational technique for the quantification of temporal summation in healthy individuals. (August 2021)

• Record Type: Journal Article
• Authors: Allison, Clouse; Korey, Loi; John Z, Srbely
• Is Part Of: Musculoskeletal science and practice. Volume 54(2021)
• Publication Date: 2021-08
• Subjects: Central sensitization -- Windup -- Quantitative sensory testing -- Chronic musculoskeletal pain; Manipulation (Therapeutics) -- Periodicals; Physical therapy -- Periodicals; Neuromuscular diseases -- Treatment -- Periodicals; Musculoskeletal system -- Diseases -- Periodicals; Manipulation (Therapeutics); Neuromuscular diseases -- Treatment; Physical therapy; Manipulation, Orthopedic; Musculoskeletal Diseases -- therapy; Neuromuscular Diseases -- therapy; Physical Therapy Modalities; Electronic journals; Periodicals; 615.82
• DOI: 10.1016/j.msksp.2021.102400
• Languages: English
• ISSNs: 2468-8630

Abstract

Abstract: Background: The pathophysiology of chronic musculoskeletal pain is linked to the neurophysiologic condition known as central sensitization. Developing reliable, sensitive and clinically feasible techniques for quantifying central sensitization is a timely priority for advancing the field of chronic pain diagnosis and management. Objective: To compare the sensitivity of the Windup Ratio, a commonly employed Quantitative Sensory Testing (QST) technique, to a novel approach, the Sumsquare method, for detecting changes in experimentally induced central sensitization. Design: Individual, randomized, controlled experimental study. Methods: A total of 37 subjects assigned to experimental (N = 18) and control (N = 19) groups. Central sensitization was experimentally induced in the C5–C6 spinal segments using topical capsaicin (0.075%); controls received a non-sensitizing placebo (Lubriderm). Windup (temporal summation) was assessed using weighted pinpricks (MRC Systems, Heidelberg, Germany) applied within regions of secondary hyperalgesia surrounding the topical capsaicin. A train of 10 stimuli was applied at baseline, 10, 20 and 30 min post-topical application and participants provided numeric pain ratings after each pinprick application. Sumsquare and Windup Ratio outcomes were calculated using the pain rating data. Results: Sumsquare outcome was significantly increased at all time points (10, 20, 30 min) post-sensitization (p < 0.05); in contrast, no differences in Windup Ratio from baseline were observed at any time point post-sensitization (p > 0.05). Conclusions: Sumsquare outcome offers greater sensitivity than Windup Ratio for detecting changes in experimentally induced central sensitization. These findings introduce a novel method for assessing changes in central sensitization in patients presenting with chronic musculoskeletal pain hypersensitivity. Highlights: Central sensitization linked to the pathophysiology of chronic musculoskeletal pain. Advancing methods of quantifying central sensitization in chronic pain is priority. Temporal summation (windup) initiates and maintains central sensitization. Sumscore more sensitive than Windup Ratio outcome at quantifying windup. Sumscore may be a valuable technique in the clinical assessment of chronic pain.