Journal of Pain Research (Dec 2020)
Altered Resting-State Connectivity with Pain-Related Expectation Regions in Female Patients with Severe Knee Osteoarthritis
Abstract
Kai Ushio,1,2 Kazuyoshi Nakanishi,3,4 Yukio Mikami,1,5 Atsuo Yoshino,6 Masahiro Takamura,7 Kazuhiko Hirata,2 Yuji Akiyama,8 Hiroaki Kimura,1,2 Yasumasa Okamoto,6 Nobuo Adachi2,3 1Department of Rehabilitation, Hiroshima University Hospital, Hiroshima, Japan; 2Sports Medical Center, Hiroshima University Hospital, Hiroshima, Japan; 3Department of Orthopedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan; 4Department of Orthopedic Surgery, Nihon University School of Medicine, Nihon University, Tokyo, Japan; 5Department of Rehabilitation Medicine, Wakayama Medical University, Wakayama, Japan; 6Department of Psychiatry and Neurosciences, Hiroshima University, Hiroshima, Japan; 7Brain, Mind and KANSEI Sciences Research Center, Hiroshima University, Hiroshima, Japan; 8Department of Clinical Radiology, Hiroshima University Hospital, Hiroshima, JapanCorrespondence: Kazuyoshi NakanishiDepartment of Orthopedic Surgery, Nihon University School of Medicine, Nihon University, Oyaguchi-Kamimachi 30-1, Itabashi-Ku, Tokyo 173-8610, JapanTel +81-3-3972-8111Fax +81-3-3957-6186Email [email protected]: Expectation affects pain experience in humans. Numerous studies have reported that pre-stimulus activity in the anterior insular cortex (aIC), together with prefrontal and limbic regions, integrated pain intensity and expectations. However, it is unclear whether the resting-state functional connectivity (rs-FC) between the aIC and other brain regions affects chronic pain. The purpose of this study was to examine the rs-FC between the aIC and the whole brain regions in female patients with severe knee osteoarthritis (OA).Patients and Methods: Nineteen female patients with chronic severe knee OA and 15 matched controls underwent resting-state functional magnetic resonance imaging. We compared the rs-FC from the aIC seed region between the two groups. A disease-specific measurement of knee OA was performed.Results: The aIC showed stronger rs-FC with the right orbitofrontal cortex (OFC), subcallosal area, and bilateral frontal pole compared with controls. The strength of rs-FC between the left aIC and the right OFC was positively correlated with the knee OA pain score (r = 0.49, p = 0.03). The strength of rs-FC between the right aIC and right OFC was positively correlated with the knee OA total score (r = 0.48, p = 0.036) and pain score (r = 0.46, p = 0.049). The OFC, subcallosal area, and frontal pole, together with the aIC, were activated during anticipation of pain stimulus. These areas have been reported as representative pain-related expectation regions.Conclusion: This was the first study to show the stronger rs-FCs between the aIC and other pain-related expectation regions in female patients with severe knee OA. Female sex and preoperative pain intensity are risk factors of persistent postoperative pain after total knee arthroplasty. It is suggested that the functional relationship between pain-related expectation regions affects the formation of severe knee OA and persistent postoperative pain following total knee arthroplasty.Keywords: functional magnetic resonance imaging, chronic pain, insular cortex, orbitofrontal cortex