title: Sonography of the anterior oblique ligament of the trapeziometacarpal joint: a study of cadavers and asymptomatic volunteers.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the ability of ultrasound to identify and characterize the anterior oblique ligament of the thumb in cadavers and asymptomatic volunteers.
  
  
  METHODS
  The anterior oblique ligaments of four cadaveric hands were imaged with a high-resolution transducer. The ligaments were then injected with 0.1% methylene blue using ultrasound guidance. To confirm identification of the ligament, the base of the thumb was immediately dissected, revealing the exact location of the dye. The bilateral ligaments in 40 asymptomatic adult volunteers were imaged.
  
  
  RESULTS
  Surgical dissection confirmed injection of methylene blue into all cadaveric ligaments. The proximal attachment of the anterior oblique ligament was well defined in all the hands, and the distal attachment was well defined in 94% of the hands. The mean thickness of the anterior oblique ligament at the metacarpal attachment (0.7 mm), midportion (0.98 mm), and trapezial attachment (0.65 mm) did not differ significantly with respect to sex, right and left side, or hand dominance and was weakly correlated with weight, height, body mass index, and age. The length of the ligament was statistically significantly different between the dominant (10.6 mm) and nondominant (9.6 mm) hands. The volar metacarpal translation with palmar abduction stress did not differ significantly between the dominant (0.7 mm) and nondominant (0.8 mm) hands. There was no association between the degree of translation and the biologic characteristics (weight, height, body mass index, and age).
  
  
  CONCLUSIONS
  High-resolution ultrasound can be used to identify and measure the thickness of the anterior oblique ligament. Dynamic ultrasound imaging can depict volar translation of the metacarpal, which may facilitate diagnosis of ligamentous injury.
authors.affiliation: Department of Radiology, McMaster University, [corrected] Hamilton, ON, Canada.
authors.forename: Mary M
authors.initials: MM
authors.lastname: Chiavaras
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Harish
authors.forename: Glen
authors.initials: G
authors.lastname: Oomen
authors.forename: Terry
authors.initials: T
authors.lastname: Popowich
authors.forename: Bruce
authors.initials: B
authors.lastname: Wainman
authors.forename: James R
authors.initials: JR
authors.lastname: Bain
mesh_terms: D000328:Adult; D002102:Cadaver; D005260:Female; D006801:Humans; D008023:Ligaments, Articular / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging; D008297:Male; D050279:Metacarpal Bones / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D008751:Methylene Blue; D018709:Statistics, Nonparametric; D014159:Transducers; D051222:Trapezium Bone / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D014463:Ultrasonography
chemical_list: D008751:Methylene Blue