title: Treatment of old neglected dislocations of the AC-joint with residual instability and/or secondary osteoarthrosis.
abstract: Resection arthroplasty of the AC joint was performed in 42 cases of osteoarthrosis and residual instability of traumatic origin including 26 shoulders with horizontal instability of more than half of the width of the clacicula and lesions of the deltotrapezoid fascial complex (Rockwood type II: 7; type III: 9; type IV: 17; type V: 9). 23 cases were treated with a sole Weaver-Dunn procedure. 26 cases with horizontal instability and lesions of the deltotrapezoid fascia (Rockwood IV and V type) were treated in 7 cases with the standard Weaver-Dunn procedure and in 19 cases with a modified Weaver-Dunn procedure in combination with a coracoclavicular (3 × 1) and acromio-clavicular (1 × 1) 1 mm PDS string augmentation and double breasting fascioplasty of the deltotrapezoid complex.
  
  
  RESULTS
  Successful results (in Patte-Score) after a minimum follow-up of 2 years (mean: 32 months) were reached in 88,4 % of cases with only Weaver/Dunn procedure with a significant difference of good and excellent results in the horizontally stable group (93.8 %) versus the horizontally unstable group (57.2 %). In the group with horizontal instability and Weaver-Dunn procedure and complex additional stabilization with fascioplasty and PDS augmentation, 89,5 % excellent and good results were found.
  
  
  CONCLUSIONS
  Cases with horizontal instability (type Rockwood IV and V) seem to be overrepresented among patients with failed conservative treatment. Resection arthroplasty with ligament transposition after Weaver/Dunn gives excellent results in posttraumatic osteoarthrosis with mainly vertical and moderate horizontal instability. In cases with advanced horizontal instability after Rockwood IV and V injuries, almost equal results can be reached by an additional coracoclavicular and acriomioclavicular PDS augmentation with deltotapezoid fascioplasty.
authors.affiliation: Orthopädische Abteilung, Klinik Fleetinsel Hamburg •, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Hedtmann
authors.affiliation: Orthopädische Abteilung, St.-Elisabeth-Krankenhaus Straubing •, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Fett
authors.affiliation: Orthopädische Universitätsklinik Bochum im St.-Josef-Hospital, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Ludwig
keywords: Key words AC joint dislocation • AC joint stabilization • AC joint arthroplasty • Rockwood classification • PDS augmentation