title: Nociception contributes to the formation of myogenic contracture in the early phase of adjuvant-induced arthritis in a rat knee.
abstract: It is unknown how joint contracture is generated in inflamed joints. This study aimed to clarify the role of nociception on the formation of joint contracture secondary to arthritis. Monoarthritis was induced by intra-articular injections of complete Freund's adjuvant (CFA) into rat knees. On day 5 after CFA injection, the passive extension range of motion (ROM) of knee joints were measured, both before and after myotomy of knee flexors, to evaluate the extent of muscular contribution to CFA-induced joint contracture. The steroidal anti-inflammatory drug dexamethasone could prevent ROM restrictions completely, both before and after myotomy. On the other hand, the opioid analgesic drug morphine did not prevent the development of restricted ROM observed after myotomy, while it did before myotomy. This indicates that nociception contributes to joint contracture through alterations in muscular structure (myogenic factors). Next, we tested the hypothesis that nociception-induced reflexive flexor muscle contractions cause myogenic contracture in arthritic joints. To do this, chemical denervation was performed by Botulinum toxin type A (BTX-A) injections into knee flexor muscles, simultaneously with CFA injections into the knee. As expected, BTX-A could alleviate ROM restrictions observed before myotomy. These findings suggest that nociceptive-related muscle contractions play an essential role in the formation of joint contracture. Thus, our study indicates that analgesic management during an early stage of joint arthritis is an essential mean to prevent the formation of joint contracture. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1404-1413, 2017.
authors: Major in Medical Engineering and Technology, Graduate School of Medical Technology and Health Welfare Sciences, Hiroshima International University, Kurose-Gakuendai 555-36, Higashi-Hiroshima, Hiroshima, Japan.
authors: Akinori
authors: A
authors: Kaneguchi
authors: Faculty of Rehabilitation, Department of Rehabilitation, Hiroshima International University, Kurose-Gakuendai 555-36, Higashi-Hiroshima, Hiroshima, Japan.
authors: Junya
authors: J
authors: Ozawa
authors: Department of Rehabilitation Science, Graduate School of Health Sciences, Kobe University, Tomogaoka 7-10-2, Suma-ku, Kobe, Hyogo, Japan.
authors: Hideki
authors: H
authors: Moriyama
authors: Faculty of Rehabilitation, Department of Rehabilitation, Hiroshima International University, Kurose-Gakuendai 555-36, Higashi-Hiroshima, Hiroshima, Japan.
authors: Kaoru
authors: K
authors: Yamaoka
mesh_terms: D000732:Androstanols; D000818:Animals; D001169:Arthritis, Experimental / Q000139:chemically induced / Q000150:complications* / Q000473:pathology; D019274:Botulinum Toxins, Type A; D003286:Contracture / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D003907:Dexamethasone; D005620:Freund's Adjuvant; D000070633:Hamstring Muscles / Q000473:pathology; D007719:Knee Joint / Q000473:pathology* / Q000502:physiology; D008297:Male; D009020:Morphine; D059225:Nociception; D011897:Random Allocation; D016059:Range of Motion, Articular; D017208:Rats, Wistar; D000077123:Rocuronium
chemical_list: D000732:Androstanols; D009020:Morphine; D003907:Dexamethasone; D005620:Freund's Adjuvant; D019274:Botulinum Toxins, Type A; D000077123:Rocuronium
keywords: inflammation; joint contracture; muscle; nociception; pain