Background: Accurate and reliable location of a coracoclavicular ligament needing reconstruction could help in the restoration of
normal biomechanics.

Objective: Reliable measurement of the distances among bony landmarks on the clavicle can lead a good correlation and predict the exact location of the coracoclavicular ligament.

Study design: Descriptive laboratory study.

Materials and Methods: Formalin-fixed cadavers were dissected, then clavicle borders and coracoclavicular ligament attachments were identified. Total clavicular length (CL the distance from conoid (ConL) and trapezoid (TrapL) ligaments to the distal end of the clavicle were measured independently by two observers. All parameter measurements and specimen characteristics were
recorded. The measurement technique used in the study was analyzed for intra and inter-observer reliability. Correlations of distances between baseline characteristics landmarks were analyzed
with regression analysis

Results: Fifteen subjects were included in the study (13 males and 2 females, mean age 70.5+13.7 years) 10 right and 5 left sides. The mean length of the clavicle was 14.4 centimeters. The distances from the center of the conoid and of the trapezoid ligaments to the distal end of the clavicle were 3.9+0.5 and 2.3+0.3 centimeters, respectively. The mean distance between the conoid and trapezoid ligaments was 1.6+0.9 centimeters. Inter-observer reliability was good, with no statistically significant differences in clavicular length or conoid length (95% confidence interval -0.797 to 0.691, p-value 0.2749 and -1.511 to 1.871, p-value 0.2153, respectively). The
correlation between clavicular length and other parameters (gender, side, conoid and trapezoid length) also showed no statistical significance. There was, however, a statistically significant difference in the correlation of the distance between the lateral clavicle and conoid bundle as well as the trapezoid bundle (coefficient 0.87 and standard error 0.30. The adjusted R-square was 0.3420, and p-value was 0.013).

Conclusion: The measurement technique in the present study showed the good reliability. The clavicular measurements described in the present study are statistically significant predictors of
the location of the conoid and trapezoid bundles.

Keywords: Coracoclavicular ligament, Location, Correlation coefficient and bony landmark