ABSTRACT
Introduction: Sacral hiatus (SH) is a significant landmark during caudal epidural block (CEB) which is employedfor analgesia and anaesthesia during a wide range of clinical conditions. This requires a thorough knowledge ofmorphometric characteristics of SH and surrounding landmarks, but variability in morphometric dimensionsexists among different populations.Aim: The aim of this study was to identify different anatomical landmarks to detect the location of SH andprovide a reference database for morphometric dimensions of SH in Indian population.Materials and Methods: The study was done on 108 dry adult human sacra. Linear measurements of the sacrawere taken with the help of digital vernier caliper and angular parameters were determined with a goniometer.Results: The most common shape of the sacral hiatus was inverted ’V’ shaped (59.3%) with the level of the apexat S4 in 66.7% and base at S5 in 86.1% cases. Morphometric dimensions of SH were found to be smaller in presentstudy as compared to reports by other researchers. Left crest-apex angle was observed to be significantly greaterthan the right crest-apex angle. (p 0.001).Conclusion: Multiple bony landmarks and their morphometric dimensions should be considered to locate the SHduring CEB. Values for various morphometric parameters of SH are less in Indians in comparison to otherpopulations, which should be contemplated during caudal epidural injections and trans-sacral thecaloscopy.
ABSTRACT
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.