title: Impact of combined skin sparing mastectomy and immediate subpectoral prosthetic reconstruction on the pectoralis major muscle function: a preoperative and postoperative comparative study.
abstract: BACKGROUND
  We assessed the subjective and objective functional loss induced by detachment of the pectoralis major muscle and whether synergistic function of adjacent muscles compensates for such loss.
  
  
  METHODS
  A preoperative to postoperative comparison of the Disability of the Arm, Shoulder and Hand score, 3-dimensional video-analysis of the range of motion, and dynamometric force assessment with electromyography registration were prospectively conducted in 22 women who underwent bilateral preventive breast surgery.
  
  
  RESULTS
  Although the statistically significant postoperative increase of the Disability of the Arm, Shoulder and Hand score (P = < 0.01) was indicative of more subjective disability, this difference is irrelevant for activities of daily life. This is in line with the observed postoperative lack of restrictions of range of motion of the shoulder. The mean postoperative maximum force measured in 4 directions reflective of the pectoralis major muscle function was 7.13 N, or 3.8%, lower than the preoperative force (P = 0.079). The mean postoperative maximum force in the 2 contramovement directions was 15.5 N, or 14%, higher than the preoperative force (P = 0.04). Electromyographically, both parts of the deltoid muscle preoperatively and postoperatively showed the same peaks in the 6 directions. Contrastingly, the clavicular part of the pectoralis major muscle postoperatively showed a statistically significant increase of peak of muscle activity in 3 of 4 directions reflective of pectoralis major function and in both contramovement directions, indicating compensatory activity.
  
  
  CONCLUSIONS
  Daily life consequences of partial detachment of the pectoralis major muscle were acceptable in our patients.
authors.affiliation: From the *Department of Plastic and Reconstructive Surgery, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital; and †Research Institute Move, Faculty of Human Movement Sciences, Vrije Universiteit, Amsterdam, the Netherlands.
authors.forename: J Joris
authors.initials: JJ
authors.lastname: Hage
authors.forename: Jorine F
authors.initials: JF
authors.lastname: van der Heeden
authors.forename: Kristel M
authors.initials: KM
authors.lastname: Lankhorst
authors.forename: Suzanne M G
authors.initials: SM
authors.lastname: Romviel
authors.forename: Maaike E
authors.initials: ME
authors.lastname: Vluttters
authors.forename: Leonie A E
authors.initials: LA
authors.lastname: Woerdeman
authors.forename: Bart
authors.initials: B
authors.lastname: Visser
authors.forename: H E J
authors.initials: HE
authors.lastname: Veeger
mesh_terms: D000328:Adult; D019928:Breast Implantation; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D008408:Mastectomy / Q000379:methods*; D008875:Middle Aged; D053581:Muscle Strength Dynamometer; D010369:Pectoralis Muscles / Q000502:physiology*; D016059:Range of Motion, Articular; D012785:Shoulder Joint / Q000502:physiology*