The Size of the Rotator Cuff and the Positional Relationship of Bony Landmarks: An Anatomical Study / 체질인류학회지

For treatment of the rotator cuff, locating the structure and position of the rotator cuff is crucial. The aim of this study is to identify the size of each rotator cuff and the locational relationship with bony landmarks, and to provide superficial landmarks for locating the tendon from the surface. Fifty-two shoulders from 26 cadavers were dissected and measured in a supine position. The central point was set as the most protrusive point on the greater tubercle of the humerus. The measurement of angles was described ventral as positive (+) and dorsal as negative (-) placing the long axis of the humeral shaft at 0degrees. The range of the angle which each rotator cuff tendon is attached to the humerus head was: 53.8~103.3 degrees for the subscapularis, -17.1~25.7 degrees for the supraspinatus, -68.4~-1.9 degrees for the infraspinatus, and -117.1~-75.7 degrees for the teres minor. The vertical inferior point drawn from the anterior edge of the acromion to the humerus was 7.5+/-11.7 degrees from the central point. The average position of the point was the midpoint of insertion of the supraspinatus tendon. The lateral horizontal point drawn from the acromial angle to the humerus was -49.4+/-14.3 degrees away and located at an average of 30% inferior to the infraspinatus tendon. Also the lateral horizontal point drawn from the most protrusive point of the coracoid process to the humerus was 63.1+/-14.7 degrees away and located at an average of 20% superior to the subscapularis tendon. Lastly, the most protrusive point of the lesser tubercle of the humerus was located at a range of 80.8+/-11.1 degrees and an average of 60% superior to the insertion of the subscapularis tendon. For the measurements of the size of the rotator cuff, there was no statistical difference between the left and right. However, the four measurements - the proximal width of the teres minor tendon, the proximal and distal width, and the length of the subscapularis tendon - showed statistically significant difference between the sexes (P<0.05). Therefore, to identify the location of the tendon structures by palpation for shoulder treatment, using the lesser tubercle for the subscapularis, the anterior edge of the acromion for the supraspinatus, and the acromial angle for the infraspinatus as landmarks is regarded to be effective.

The Location of the Modiolus in Living Korean / 체질인류학회지

Modiolus is convergence of the facial muscles at the angle of the mouth, and its shape and size varying with individual, age, sex and ethnicity. In the previous study, the modiolus was usually located under the horizontal line at the mouth angle. In most medical schools, the cadavers are of later ages and their facial muscles have lost their elasticity as they got older. The purpose of this study is to identify the location of the modiolus in live young Korean and to compare it with that of Korean cadavers from the previous study. Participants were one hundred students of the catholic medical school with a mean age of 24 years. Experimenter palpated the modiolus of each student with thumb and index finger. The average young live Korean modiolus was located at 14.4 mm lateral to mouth angle and 1.6 mm below the horizontal line of the mouth angle. Commonly, it is located below the mouth angle in 124 sides (62%). There was difference between horizontal distance of female and of male, and vertical distance of right and of left. The location of the modiouls was symmetric in 67%. These results were consistent with the previous study using Korean cadavers. Therefore these results suggest that the location of the modiolus is below to the mouth angle in large number of Koreans.