title: Effect of highly purified capsaicin on articular cartilage and rotator cuff tendon healing: An in vivo rabbit study.
abstract: Highly purified capsaicin has emerged as a promising injectable compound capable of providing sustained pain relief following a single localized treatment during orthopedic surgical procedures. To further assess its reliability for clinical use, the potential effect of highly purified capsaicin on articular cartilage metabolism as well as tendon structure and function warrants clarification. In the current study, rabbits received unilateral supraspinatus transection and repair with a single 1 ml injection of capsaicin (R+C), PEG-only placebo (R+P), or saline (R+S) into the glenohumeral joint (GHJ). An additional group received 1 ml capsaicin onto an intact rotator cuff (I+C). At 18 weeks post-op, cartilage proteoglycan (PG) synthesis and content as well as cell viability were similar (p>0.05) across treatment groups. Biomechanical testing revealed no differences (p>0.05) among tendon repair treatment groups. Similarly, histologic features of both cartilage and repaired tendons showed minimal differences across groups. Hence, in this rabbit model, a single injection of highly purified capsaicin into the GHJ does not induce a deleterious response with regard to cartilage matrix metabolism and cell viability, or rotator cuff healing. These data provide further evidence supporting the use of injectable, highly purified capsaicin as a safe alternative for management of postoperative pain following GHJ surgery.
authors.affiliation: Department of Orthopedic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Nicole A
authors.initials: NA
authors.lastname: Friel
authors.affiliation: Department of Surgery, Mount Sinai Hospital Medical Center, Chicago, Illinois.
authors.forename: Allison G
authors.initials: AG
authors.lastname: McNickle
authors.affiliation: CGH Medical Center, Sterling, Illinois.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: DeFranco
authors.affiliation: BioCare Corporation, Lujhu Township, Taiwan.
authors.forename: FanChia
authors.initials: F
authors.lastname: Wang
authors.affiliation: Department of Orthopedic Surgery, Rush University Medical Center, Chicago, Illinois.
authors.forename: Elizabeth F
authors.initials: EF
authors.lastname: Shewman
authors.affiliation: Department of Orthopedic Surgery, Rush University Medical Center, Chicago, Illinois.
authors.forename: Nikhil N
authors.initials: NN
authors.lastname: Verma
authors.affiliation: Department of Orthopedic Surgery, Rush University Medical Center, Chicago, Illinois.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Cole
authors.affiliation: Department of Orthopedic Surgery, Rush University Medical Center, Chicago, Illinois.
authors.forename: Bernard R
authors.initials: BR
authors.lastname: Bach
authors.affiliation: Department of Orthopedic Surgery, Rush University Medical Center, Chicago, Illinois.|Department of Biochemistry, Rush University Medical Center, Chicago, Illinois.
authors.forename: Susan
authors.initials: S
authors.lastname: Chubinskaya
authors.affiliation: Annexon Bioscience, South San Francisco, California.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Kramer
authors.affiliation: Department of Orthopedic Surgery, Rush University Medical Center, Chicago, Illinois.
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Wang
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002211:Capsaicin / Q000627:therapeutic use*; D002358:Cartilage, Articular / Q000187:drug effects* / Q000601:surgery; D002470:Cell Survival; D008297:Male; D010149:Postoperative Pain; D011312:Pressure; D011509:Proteoglycans / Q000378:metabolism; D011817:Rabbits; D017006:Rotator Cuff / Q000187:drug effects* / Q000601:surgery; D012785:Shoulder Joint / Q000473:pathology; D013314:Stress, Mechanical; D013708:Tendon Injuries / Q000188:drug therapy* / Q000601:surgery; D013710:Tendons / Q000187:drug effects* / Q000601:surgery
chemical_list: D011509:Proteoglycans; D002211:Capsaicin
keywords: anesthetic; capsaicin; cartilage; rotator cuff; tendon