title: Scoring of Deformed Costal Cartilages Reduces Postoperative Pain after Nuss Procedure for Pectus Excavatum.
abstract: OBJECTIVE
  The present study aims to elucidate whether or not scoring deformed cartilages reduces postoperative pain after the Nuss procedure for pectus excavatum patients.
  
  
  METHODS
  A total of 46 pectus excavatum patients for whom the Nuss procedure was conducted were included in the study. The patients were categorized into two groups, depending on whether or not the supplementary maneuver of scoring deformed cartilages was performed in addition to the Nuss procedure. Patients for whom deformed costal cartilages were scored were categorized as the Scoring Group (n = 24); those who received no such scoring were categorized as the Non-Scoring Group (n = 22). After evaluating the maximum stresses occurring on the thoraces by means of dynamic simulation using finite element analyses, intergroup comparison of the maximum von-Mises stress values was performed. Furthermore, after quantifying postoperative pain as the frequency with which patients injected anesthetics through an epidural pain-control system within 2 postoperative days, the degree of pain was compared between the two groups.
  
  
  RESULTS
  The maximum stresses occurring on the thorax were significantly greater for the Non-Scoring Group than for the Scoring Group; injection frequency was also greater for the Non-Scoring Group (average 4.9 times for 2 days) than for the Scoring Group (average 2.5 times for 2 days).
  
  
  CONCLUSIONS
  High stresses occur due to the performance of the Nuss procedure, causing postoperative pain. The stresses can be reduced by performing supplementary scoring on deformed cartilages. Accordingly, postoperative pain is reduced.
authors.affiliation: Department of Plastic Surgery, Kagawa University, Takamastu, Kagawa, Japan.
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Nagasao
authors.affiliation: Department of Plastic Surgery, Kagawa University, Takamastu, Kagawa, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hamamoto
authors.affiliation: Department of Plastic Surgery, Kagawa University, Takamastu, Kagawa, Japan.
authors.forename: Motoki
authors.initials: M
authors.lastname: Tamai
authors.affiliation: Department of Plastic Surgery, Kagawa University, Takamastu, Kagawa, Japan.
authors.forename: Tetsukuni
authors.initials: T
authors.lastname: Kogure
authors.affiliation: Department of Plastic Surgery, Shanghai Second Military Medical College, Changzheng Hospital, Shanghai, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Department of Mechanical Engineering, Keio University, Yokohama, Kanagawa, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Takano
authors.affiliation: Department of Plastic Surgery, Kagawa University, Takamastu, Kagawa, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Tanaka
mesh_terms: D000293:Adolescent; D000328:Adult; D016058:Analgesia, Patient-Controlled; D001696:Biomechanical Phenomena; D002648:Child; D003198:Computer Simulation; D066186:Costal Cartilage / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D055119:Elastic Modulus; D005260:Female; D020342:Finite Element Analysis; D005660:Funnel Chest / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D019637:Orthopedic Procedures / Q000009:adverse effects / Q000379:methods*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D013249:Sternum / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D013314:Stress, Mechanical; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult