title: Arthroscopic Stabilization of Chronic Acromioclavicular Joint Dislocations: Triple- Versus Single-Bundle Reconstruction.
abstract: BACKGROUND
  Arthroscopically assisted single-bundle (SB) or double-bundle coracoclavicular (CC) ligament reconstruction using autologous tendon grafts has been reported to provide acromioclavicular (AC) joint (ACJ) stability in chronic instability cases. Recently, additional AC ligament reconstruction to provide triple-bundle (TB) stabilization has been introduced but lacks a comparison of clinical and radiological outcomes.
  
  
  OBJECTIVE
  Arthroscopically assisted anatomic TB CC and AC reconstruction yields superior clinical and radiological results when compared with nonanatomic SB CC reconstruction.
  
  
  METHODS
  Cohort study; Level of evidence, 2.
  
  
  METHODS
  Twenty-six patients (mean [±SD] age, 46.9 ± 12.8 years) suffering from chronic high-grade ACJ instability underwent ACJ stabilization using autologous hamstring grafts. Twelve patients underwent combined anatomic TB CC and AC reconstruction using a semitendinosus tendon with clavicular interference screw fixation (TB group), and 14 underwent isolated SB CC reconstruction using the AC GraftRope system with a gracilis tendon (SB group). After a minimum follow-up of 2 years (mean, 29.0 ± 7.4 months), patients were evaluated radiologically and clinically using the Constant, American Shoulder and Elbow Surgeons (ASES), Taft, and Acromioclavicular Joint Instability Score (ACJI) outcome measures.
  
  
  RESULTS
  The mean Constant score increased significantly in both groups, from 71.6 preoperatively to 88.8 postoperatively in the TB group and from 67.8 to 82.6 in the SB group (P ≤ .009). No intergroup difference was found regarding the final Constant or ASES scores. Regarding the ACJ-specific scores, the final outcomes were significantly different: 10.9 (TB group) versus 9.0 (SB group) for the mean Taft score (P = .018) and 84.7 versus 58.4, respectively, for the mean ACJI score (P = .0001). No significant radiological difference was found regarding the mean CC distance (10.7 mm [TB group] vs 13.1 mm [SB group]). The TB group showed superior horizontal ACJ stability (P = .011), which was associated with a better clinical outcome according to the ACJI and Taft scores. In the SB group, the rate of ACJ instability recurrence was higher (21% vs 8% [TB group]).
  
  
  CONCLUSIONS
  Combined arthroscopically assisted anatomic TB CC and AC ligament reconstruction using an autologous semitendinosus tendon graft provides superior clinical and radiological results compared with isolated nonanatomic SB CC ligament reconstruction using the AC GraftRope system. In particular, the TB technique can better restore horizontal ACJ stability, which is associated with superior ACJ-specific outcome scores.
authors.affiliation: Shoulder and Elbow Surgery, ATOS Clinic Munich, Munich, Germany Department of Traumatology and Sports Injuries, Paracelsus Medical University, Salzburg, Austria tauber@atos-muenchen.de.
authors.forename: Mark
authors.initials: M
authors.lastname: Tauber
authors.affiliation: Shoulder and Elbow Surgery, ATOS Clinic Munich, Munich, Germany.
authors.forename: Dennis
authors.initials: D
authors.lastname: Valler
authors.affiliation: Shoulder and Elbow Surgery, ATOS Clinic Heidelberg, Heidelberg, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Lichtenberg
authors.affiliation: Shoulder and Elbow Surgery, ATOS Clinic Heidelberg, Heidelberg, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Magosch
authors.affiliation: Department of Traumatology and Sports Injuries, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Philipp
authors.initials: P
authors.lastname: Moroder
authors.affiliation: Shoulder and Elbow Surgery, ATOS Clinic Munich, Munich, Germany Shoulder and Elbow Surgery, ATOS Clinic Heidelberg, Heidelberg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Habermeyer
mesh_terms: D000173:Acromioclavicular Joint / Q000293:injuries* / Q000601:surgery; D000328:Adult; D002908:Chronic Disease; D002968:Clavicle / Q000601:surgery; D015331:Cohort Studies; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000601:surgery*; D007593:Joint Instability / Q000209:etiology / Q000601:surgery*; D008023:Ligaments, Articular / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care / Q000379:methods; D013710:Tendons / Q000637:transplantation; D014182:Transplantation, Autologous; D016896:Treatment Outcome
keywords: ACJ dislocation; GraftRope; anatomic reconstruction; chronic; gracilis tendon; semitendinosus tendon