Variations in anatomy at the suprascapular notch possibly causing suprascapular nerve entrapment: an anatomical study

Abstract

The purpose of the study was to determine anatomical variations at the suprascapular notch for better understanding of possible predisposing factors for suprascapular nerve entrapment. We dissected 32 shoulders of 16 cadavers between the ages of 39 and 74 years. We observed abnormally oriented superior fibers of the subscapularis muscle in five shoulders of the 16 cadavers, which were covering the entire anterior surface of the suprascapular notch and significantly reducing the available space for the suprascapular nerve. We also detected anterior coracoscapular ligament in six of the 32 shoulders, and calcified superior transverse scapular ligament in four of the shoulders. In this study, we classified the variations for the superior transverse scapular ligament. In conclusion, knowing the anatomical variations in detail along the course of the suprascapular nerve might be important for better understanding of location and source of the entrapment syndrome, especially for individuals who are involved in violent overhead sports activities such as volleyball and baseball. To our knowledge, close relationship of subscapularis muscle with the suprascapular nerve as a possible risk factor for suprascapular nerve entrapment has not been mentioned previously.

A Study on the Morphological Variations of the Suprascapular Notch in the Population of Eastern Delta Region of Tamil Nadu

“…The observations of the various types of suprascapular notch according to the specifications of Rengachary et al classification is represented in Fig.1 [9] classified suprascapular notch as U-shaped and V-shaped. Bayramoglu reported 3 types -U-shaped, V-shaped and J-shaped [10]. The present study is based on Rengachary classification.…”

A Morphometric Study of Suprascapular Notch and Its Safe Zone

“…Therefore various studies have been done on suprascapular notch variations in different populations. Rengachary et al, [6] Ticker et al, [11], Bayramoglu et al, [12] Natsis et al, [13] Sinkeet [14] Wang [15] and Polguj [16]. Depending on the shape of suprascapular notch and the degree of ossification, Rengachary et al, [6] classified SSN into six types .…”

Arthroscopic Treatment of Suprascapular Nerve Neuropathy

“…Rengachary et al (Rengachary, Burr et al 1979;Bayramoglu, Demiryurek et al 2003). The existence of different morphologies of the notch has been corroborated by more investigators.…”