Protective and Predisposing Morphological Factors in Suprascapular Nerve Entrapment Syndrome: A Fundamental Review Based on Recent Observations

Abstract

Suprascapular nerve entrapment syndrome (SNES) is a neuropathy caused by compression of the nerve along its course. The most common compression sites include the suprascapular notch and the spinoglenoid notch. The aim of this article was to review the anatomical factors influencing the occurrence of SNES in the light of the newest reports. Potential predisposing morphological factors include a V-shaped, narrow, or “deep” suprascapular notch; a band-shaped, bifurcated, or completely ossified superior transverse scapular ligament (STSL); particular arrangements of the suprascapular nerve and vessels at the suprascapular notch. A very recent report indicates structures at the suprascapular notch region that may protect from SNES, such as the suprascapular notch veins (SNV). The role of the anterior coracoscapular ligament (ACSL) is still not clear. While some studies indicate that it may predispose for SNES, the newest study proposes a protective function. Knowledge of these variations is essential for arthroscopic and other surgical procedures of this area in order to avoid iatrogenic injury of the suprascapular nerve or unexpected bleeding from the suprascapular vessels running alongside the STSL.

An Unusual Bilateral Duplication of the Suprascapular Vein and Its Relation to the Superior Transverse Scapular Ligament Revealed by Anatomage Table

“…According to Labertowicz et al the occurrence of an accessory vein (double or triple vein), in cases in which the SA crosses under the STSL together with the SN, resulted in nerve damage due to blood pressure and high incidence of SNES (6). Other causes of nerve damage include traumatic injuries in the areas of the clavicle or scapula and its joints, iatrogenic injuries in the process of a surgical operation, excessive overload in athletes or physical laborers, tuberous alterations of this area, or even systemic diseases.…”

Neuropatía por atrapamiento del nervio supraescapular: reporte de dos casos.

“…La neuropatía del NSE fue descrita por André Thomas en 1936 y es una de las múltiples causas de dolor en la región del hombro (1)(2)(3)(4) .…”

“…Entre los factores de riesgo descritos para padecer una neuropatía por atrapamiento del NSE se citan: la morfología de la escotadura escapular, la osificación del ligamento transverso de la escápula, deportes que exijan elevar de forma repetida al brazo por arriba de la cabeza, traumatismos, fracturas de clavícula o escápula, procedimientos quirúrgicos en la región y gangliones articulares, entre otras causas (1,4,9) .…”

“…Sin embargo, representa el 1% de todas las causas de dolor en la región del hombro (1) . Este síntoma es un motivo de consulta relativamente frecuente en traumatología.…”

The Influence of Suprascapular Notch Shape on the Visualization of Structures in the Suprascapular Notch Region: Studies Based on a New Four-Stage Ultrasonographic Protocol

“…This variation is important from the clinical point of view. First, because it is the most common site of suprascapular nerve compression and injury [ 8 , 9 ], and, second, because the morphological variations in this region may be a risk factor of these pathologies [ 10 , 11 ].…”