Table 1. The classification systems of the suprascapular notch morphology.

MD, maximum depth; MTD, middle transverse diameter; STD, superior transverse diameter

Classification	Type	Characterization
Natsis et al. (2007) [1]	I	Without a discrete notch
	II	Notch with greater transverse than vertical diameter (U-shaped)
	III	Notch with greater vertical than transverse diameter (V-shaped)
	IV	Suprascapular foramen
	V	Suprascapular notch and foramen
Rengachary et al. (1979) [3]	I	Wide depression of the scapula superior border
	II	V-shaped notch
	III	U-shaped notch
	IV	Small V-shaped notch
	V	U-shaped with partial ossification of the ligament medial part
	VI	Completely ossified ligament with foramen
Polguj et al. (2011) [4]	IA	MD>STD and STD
	IB	MD>STD and STD=MTD
	IC	MD>STD and STD>MTD
	II	MD=STD=MTD
	IIIA	MD
	IIIB	MD
	IIIC	MDMTD
	IV	Suprascapular foramen
	V	Without a discrete notch