Anatomical, histological and radiological study of the rotator cuff interval of the shoulder

The Rotator cuff interval [RCI] is the triangular capsular space between the insertion of tendons of supraspinatus and subscapularis muscles. This RCI is supposed to be reinforced superficially by the coracohumeral ligament and deeply by the superior glenohumeral ligament SGHL. In addition to the ligamentous structures, the participation of the supraspinatus and subscapularis muscles tendons in the composition of the RCI has been pointed out. The aim of the present work was to study RCI, its boundaries and components, macroscopically and microscopically in correlation to MRI. Fourteen adult human cadaveric shoulder regions [5 right and 9 left] obtained from the Anatomy Department, Faculty of Medicine, Ain Shams University, were used in the present study. Specimens with gross pathology, trauma or previous surgery were excluded. Retrospectively the normal MRI findings were examined in 19 volunteers [10 right and 9 left shoulders, after obtaining consents] to demonstrate the boundaries and contents of the RCI using 1.5 tesla [General Electric Medical System [Milwaukee]. Results gross dissection at the apex of RCI revealed extension of fibers from subscapularis and supraspinatus tendons across the location of the RCI. They merge together in this region forming a confluence of fibers amalgamating with the capsule from outside. The long bicipital tendon was supported anteriorly by the suspension sling formed by the SGHL which seems to stabilize the long head of biceps in the RCI. The subscapularis tendon and the middle glenohumeral [GH] ligament, supported the antero-medial wall of the RCI. Sections taken from the lateral part of the roof, near the apex of the RCI and the superomedial part showed three distinct layers of connective tissue bundles. In sections taken in close proximity to the tendinous insertions into the tuberosities showed a zone of fibrocartilage. Sections from antero-medial part of the roof of RCI showed a meshwork of loose connective tissue. The RCI is best demonstrated in sagittal cuts. However, coronal and axial cuts can be helpful in identification of the relationship and contents. The coracohumeral [CHL] is always well identified in the mid portion of the RCI and is visualized in all planes, but sagittal images are the most useful for analysis of this structure. In conclusion studying the anatomy of RCI and determining [RCI] at MR imaging is important as it will provide a scientific background to the surgeon to repair any interval tear to stabilize the shoulder and may explain to some extent the superior instability observed in shoulders with rotator cuff tears

Anatomic and radiographic study of Egyptian calcaneal angles in comparison to other populations

This study was performed to determine the mean Egyptian calcaneal angles: Bohler's angle [BA] and Gissane's angle [GA] in comparison to other populations. Lateral plain radiographs of 267 normal Egyptians' feet and ankles, of 184 females and 83 males, with an age range of 17-69 years, were studied retrospectively at Erfan hospital Jeddah KSA, between August 2005 to July 2006. Six reformatted CT scans and Eight MRI of the ankle were studied measuring the BA and GA to determine the fallacies in radiographic readings. In addition, 30 adult dry calcaneal bones [17 right and 13 left], 7 of which were of known sex [5 males and 2 females] were collected from the Anatomy Department, Faculty of Medicine, Ain Shams University. The values of BA and GA were estimated on the dry bones and their lateral plain radiographs. The range, mean and standard deviation of each angle were calculated. Using the student t-test and One-Way Analysis of Variance, the presence of statistical differences between age, gender and side of the body were determined for both angles. Moreover, the results of the present study were compared with those of other populations to determine any racial differences. The mean of BA in the Egyptian population was 31.5° with a range of 15-48° in males and 30.5° with a range of 19-42° in females. The mean of GA was 117° with a range of 100-134° in males and 125° with a range of 101-149° in females. Bohler's angle and GA were not significantly related to gender or side of the body. However, there were statistical significant differences between different age groups. Moreover, the range of both angles was greater than that reported in other population-samples. No significant different values were obtained between dry bones and those of plain radiographs. This study showed the statistical dissimilarity between the different populations as regards to BA and GA and reinforced the need to establish the normal ranges of BA and GA in a given population. These angles were shown to be an accepted method for quantifying fracture displacement and predicting the prognosis of calcaneal fractures. By using simple radiographic measurements, the data of the present study might lead to better diagnosis and treatment