title: Relationship between coracoacromial arch and rotator cuff analysed by a computer-assisted method.
abstract: BACKGROUND
  In this paper we describe and assess the feasibility of a computer-assisted method which could be useful to investigate the mechanism of subacromial impingment of the shoulder.
  
  
  METHODS
  The relationship between the infraspinatus and supraspinatus and the coracoacromial (CA) arch during passive elevation and abduction are described. The methodology is based on the use of a tracker for recording surfaces and passive movements and data elaboration using dedicated software.
  
  
  RESULTS
  In four cadavers, we observed that the minimal distances between the rotator cuff insertions and CA arch were realized at 45 degrees abduction between the acromion and infraspinatus, at 50-90 degrees elevation between the acromion and supraspinatus and also at 45-70 degrees abduction between the CA ligament and supraspinatus. This study showed that the proposed method is able to provide repeatable kinematic data (ICC > or = 0.90), numerical anatomical data comparable with the literature and, moreover, individual measurements on the shoulder joint.
  
  
  CONCLUSIONS
  This preliminary results support the extension of the methodology to an in vivo protocol to be used during computer-assisted arthroscopic surgery.
authors.affiliation: Laboratorio di Biomeccanica, Istituti Ortopedici Rizzoli, Bologna, Italy. d.casino@biomec.ior.it
authors.forename: Daniela
authors.initials: D
authors.lastname: Casino
authors.forename: Danilo
authors.initials: D
authors.lastname: Bruni
authors.forename: Stefano
authors.initials: S
authors.lastname: Zaffagnini
authors.forename: Sandra
authors.initials: S
authors.lastname: Martelli
authors.forename: Andrea
authors.initials: A
authors.lastname: Visani
authors.forename: Pau Golanò
authors.initials: PG
authors.lastname: Alvarez
authors.forename: Maurilio
authors.initials: M
authors.lastname: Marcacci
mesh_terms: D000173:Acromioclavicular Joint / Q000033:anatomy & histology* / Q000502:physiology / Q000503:physiopathology; D000174:Acromion / Q000033:anatomy & histology* / Q000502:physiology; D053587:Arthrometry, Articular; D001696:Biomechanical Phenomena; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008023:Ligaments, Articular / Q000033:anatomy & histology / Q000502:physiology / Q000503:physiopathology; D017006:Rotator Cuff / Q000033:anatomy & histology* / Q000502:physiology; D012782:Shoulder / Q000033:anatomy & histology / Q000502:physiology; D019534:Shoulder Impingement Syndrome / Q000503:physiopathology; D012785:Shoulder Joint / Q000033:anatomy & histology / Q000502:physiology / Q000503:physiopathology