title: A biomechanical evaluation of an anatomical coracoclavicular ligament reconstruction.
abstract: BACKGROUND
  Despite numerous surgical techniques described, there have been few studies evaluating the biomechanical performance of acromioclavicular joint reconstructions.
  
  
  OBJECTIVE
  To compare a newly developed anatomical coracoclavicular ligament reconstruction with a modified Weaver-Dunn procedure and a recently described arthroscopic method using ultrastrong nonabsorbable suture material.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Forty-two fresh-frozen cadaveric shoulders (72.8 +/- 13.4 years) were randomly assigned to 3 groups: arthroscopic reconstruction, anatomical coracoclavicular reconstruction, and a modified Weaver-Dunn procedure. Bone mineral density was obtained on all specimens. Specimens were tested to 70 N in 3 directions, anterior, posterior, and superior, comparing the intact to the reconstructed states. Superior cyclic loading at 70 N for 3000 cycles was then performed at a rate of 1 Hz, followed by a load to failure test (120 mm/min) to simulate physiologic states at the acromioclavicular joint.
  
  
  RESULTS
  In comparison to the intact state, the modified Weaver-Dunn procedure had significantly (P < .05) greater laxity than the anatomical coracoclavicular reconstruction or the arthroscopic reconstruction. There were no significant differences in bone mineral density (g/cm(2)), load to failure, superior migration over 3000 cycles, or superior displacement. The anatomical coracoclavicular reconstruction had significantly less (P < .05) anterior and posterior translation than the modified Weaver-Dunn procedure. The arthroscopic reconstruction yielded significantly less anterior displacement (P < .05) than the modified Weaver-Dunn procedure.
  
  
  CONCLUSIONS
  The anatomical coracoclavicular reconstruction has less anterior and posterior translation and more closely approximates the intact state, restoring function of the acromioclavicular and coracoclavicular ligaments.
  
  
  CONCLUSIONS
  A more anatomical reconstruction using a free tendon graft of both the trapezoid and conoid ligaments may provide a stronger, permanent biologic solution for dislocation of the acromioclavicular joint. This reconstruction may minimize recurrent subluxation and residual pain and permit earlier rehabilitation.
authors.affiliation: University of Connecticut Health Center, Farmington, USA. admazzocca@yahoo.com
authors.forename: Augustus D
authors.initials: AD
authors.lastname: Mazzocca
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Santangelo
authors.forename: Sean T
authors.initials: ST
authors.lastname: Johnson
authors.forename: Clifford G
authors.initials: CG
authors.lastname: Rios
authors.forename: Mark L
authors.initials: ML
authors.lastname: Dumonski
authors.forename: Robert A
authors.initials: RA
authors.lastname: Arciero
mesh_terms: D000173:Acromioclavicular Joint / Q000293:injuries / Q000503:physiopathology / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D001178:Arthroplasty / Q000379:methods*; D001696:Biomechanical Phenomena; D015519:Bone Density; D002102:Cadaver; D006801:Humans; D004204:Joint Dislocations / Q000503:physiopathology / Q000601:surgery*; D007593:Joint Instability / Q000503:physiopathology* / Q000601:surgery; D008023:Ligaments, Articular / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D016059:Range of Motion, Articular; D013536:Suture Techniques; D016474:Weight-Bearing