Morphometric study of suprascapular notch in Indian dry scapulae with specific reference to the incidence of completely ossified superior transverse scapular ligament.
BACKGROUND
The suprascapular notch, a depression on the lateral part of the superior border of the scapula, medial to the coracoid process, is bridged by the superior transverse scapular ligament, which is sometimes ossified and the foramen which is thus completed, transmits the suprascapular nerve to the supraspinatus fossa. Variations in the morphology of suprascapular notch have been identified as one of the causes of suprascapular nerve entrapment. Rengachary et al. classified this notch into six types, based on its shape.


OBJECTIVE
To study morphological variations of suprascapular notch in Indian dry scapulae and to analyze the incidence of completely ossified superior transverse scapular ligament with other ethnic populations which have been cited earlier.


METHODS
A total of 400 human dry scapulae which were obtained from the Department of Anatomy of selected eight medical colleges were analyzed. The type of suprascapular notch was noted and it was recorded as per the description given by Rengachary et al. The results of the present study were compared with the results of previous authors in different populations.


RESULTS
In our study, out of 400 scapulae, 40 (10%), were identified to have completely ossified superior transverse scapular ligaments. The frequencies of various types of suprascapular notches were: Type I -20%, Type II -10%, Type III -52%, Type IV -4%, Type V -4%, Type VI -10%.


CONCLUSIONS
Since the suprascapular nerve entrapment syndrome might be caused by complete ossification of superior transverse scapular ligament with formation of suprascapular foramen and other morphometric variations of suprascapular notch, the knowledge on such variations is essential for clinicians, for making a proper diagnosis and for planning the most suitable surgical intervention.
Assistant Professor, Department of Anatomy, Mahatma Gandhi Medical College and Research Institute , Pillaiyarkuppam, Pondicherry, India .
Usha
U
Kannan
Associate Professor, Department of General Surgery, Mahatma Gandhi Medical College and Research Institute , Pillaiyarkuppam, Pondicherry, India .
N S
NS
Kannan
Professor, Department of Anatomy, Mahatma Gandhi Medical College and Research Institute , Pillaiyarkuppam, Pondicherry, India .
J
J
Anbalagan
Professor and HOD, Department of Anatomy, Mahatma Gandhi Medical College and Research Institute , Pillaiyarkuppam, Pondicherry, India .
Sudha
S
Rao
Superior transverse scapular ligament; Suprascapular foramen; Suprascapular nerve; Suprascapular notch