AUTHORS’ REPLY:
Thank you, Azzat-AL Redouan and David Kachlikh, for your interest in reading our article (Bagoji et al) entitled “Anatomical Variations of the Suprascapular Notch and its Importance in Suprascapular Entrapment Neuropathy”.
Firstly, the presented scapula in Figure 6, the suprascapular ligament is ossified and converted into the foramen. As per the literature available on the website, Shane Tubbs et al (1), Peæina M et al (2), M Polguj et al (3) reported that the nerve entrapment syndrome was mainly due to ossification of the suprascapular ligament. We suggest that the occurrence of the bony bridge formed by ossified SSL could have a genetic basis, and the frequency of completely ossified suprascapular ligament varies throughout the world and can be a risk factor for surgical explorations. The incidence of entrapment of suprascapular ligament largely increases with strenuous overhead abduction, i.e. in repeated overhead motion such as volleyball, baseball pitching, and trauma contributes to ossification of the ligament (1), resulting in bony foramen through which the suprascapular nerve travels and may lead to suprascapular nerve compression (4).
Secondly, the W-shaped SSN variant was a unique finding in our study as per the limited available literature. As reported by R. Vandana et al (3), W-shaped notch is proposed as a possible cause of the suprascapular nerve entrapment syndrome due to changed morphology and reduced morphometry. The occurrence of a W-shaped notch may be due to developmental abnormality scapula or abnormal attachment or division of the suprascapular ligament, or change in the course of suprascapular blood vessels. The presence of an inconspicuous additional notch (W) may cause entrapment of the suprascapular nerve, compressing the suprascapular blood vessels (6).
Thirdly, measurements of ‘V’ shaped notch had the lowest width/depth ratio, and this parameter was comparatively lesser than the other various notch parameters in our study; these findings were almost similar to those reported by Antoniadis et al (7), who stated that a V-shaped notch was more likely to be connected with suprascapular nerve pathology. The V-shaped notch is also supported by the sling effect theory of suprascapular nerve entrapment, proposed in 1979 by Rangrery et al (8), who described the V-shaped sharp bony margins of the scapular notch that could press the suprascapular nerve. Repeated kinking irritates the nerve and may induce microtrauma that results in neuropathy (9).
Conflict of interests: none declared.
Financial support: none declared.
Contributor Information
Ishwar BAGOJI, Assistant professors, Department of Anatomy, BLDE (Deemed To be University)’s Shri BMPatil Medical College, Hospital & Research Center, Vijayapura, Karnataka, India.
G A HADIMANI, Assistant professors, Department of Anatomy, BLDE (Deemed To be University)’s Shri BMPatil Medical College, Hospital & Research Center, Vijayapura, Karnataka, India.
Ambadasu BHARATHA, Lecturer in Pharmacology, Faculty of Medical Sciences, University of The West Indies,Cave Hill Campus, BARBADOS, WI.
References
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