title: Comparison of single and two-tunnel techniques during open treatment of acromioclavicular joint disruption.
abstract: BACKGROUND
  Coracoclavicular (CC) ligament reconstruction with semitendinosus tendon (ST) grafts has become more popular and has achieved relatively good results; however optimal reconstruction technique, single-tunnel or two-tunnel, still remains controversial. This paper is to compare the clinical and radiographic data of allogenous ST grafting with single- or two-tunnel reconstruction techniques of the AC joint.
  
  
  METHODS
  The outcomes of 21 consecutive patients who underwent anatomical reduction and ST grafting for AC joint separation were reviewed retrospectively. Patients were divided into two groups: single-tunnel group (11) and two-tunnel group (10). All patients were evaluated clinically and radiographically using a modified UCLA rating scale.
  
  
  RESULTS
  The majority of separations (18 of 21) were Rockwood type V, with one each in type III, IV and VI categories. The overall mean follow-up time was 16 months, and at the time of the latest follow-up, the overall mean UCLA rating score was 14.1 (range 8-20).The percentage of good-to-excellent outcomes was significantly higher for patients with the two-tunnel technique than for those with the one-tunnel technique (70% vs. 18%, respectively, p = 0.03). Within the single-tunnel group, there was no statistically significant difference in percentage of good-to-excellent outcomes between patients with vs. without tightrope augmentation (17% vs 20%, p > 0.99). Similarly, within the two-tunnel group, there was no significant difference in the percentage of good-to-excellent outcomes between the graft only and augment groups (67% vs. 75%, p > 0.99).
  
  
  CONCLUSIONS
  Anatomical reduction of the AC joint and reconstruction CC ligaments are crucial for optimal joint stability and function. Two-tunnel CC reconstruction with an allogenous ST graft provides superior significantly better radiographic and clinical results compared to the single-tunnel reconstruction technique.
authors.affiliation: Department of Orthopaedic Surgery, Third Hospital of Hebei Medical University, Shijiazhuang, Hebei 050051, China. drzyhou@gmail.com.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Hou
authors.forename: Jove
authors.initials: J
authors.lastname: Graham
authors.forename: Yingze
authors.initials: Y
authors.lastname: Zhang
authors.forename: Kent
authors.initials: K
authors.lastname: Strohecker
authors.forename: Daniel
authors.initials: D
authors.lastname: Feldmann
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Bowen
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Wade
authors.initials: W
authors.lastname: Smith
mesh_terms: D000173:Acromioclavicular Joint / Q000293:injuries* / Q000503:physiopathology / Q000601:surgery; D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008023:Ligaments, Articular / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D016059:Range of Motion, Articular; D019651:Plastic Surgery Procedures / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult