Drilling technique for truly anatomic reconstruction of coracoclavicular ligaments

Abstract

Objective To determine the drilling parameters for truly anatomic reconstruction of coracoclavicular ligament (TARGL) on the three-dimensional and cadaveric models. Methods Three-dimensional models of 105 normal acromioclavicular (AC) joints were reconstructed by the image-processing software (Superlmage). The attachment sites and footprint dimensions of the conoid and trapezoid ligaments were defined and adjusted according to anatomic parameters. Virtual tunnels were created on the clavicle and the coracoid process to simulate TARCL for determination of drilling parameters, on the basis of which 12 cadaver models with AC joint dislocation were used to further evaluate the feasibility and safety of TARCL. Results No cortical breaches were found when TARCL was performed on either computer or cadaveric models of AC joint dislocation. There were no fractures of the clavicle or of the conoid process in the cadaveric models. In the drilling process of coracoid process, the anteversion angulation of the conical drill bit ranged from 10° to 15° (mean, 12.4°), the extraversion angulation of the conoid drill bit varied from 5° to 10° (mean, 6.8°), and the anteversion angulation of the trapezoidal drill bit ranged from 20° to 30° (mean, 25.2°). Conclusions TARCL is safe and feasible. Drilling with appropriate position and direction is the key to success. Key words: Acromioclavicular joint; Ligaments; Models, anatomic; Autopsy; Drilling technique