A Proposal for a New Classification of the Supernumerary Heads of the Biceps Brachii Muscle

Table 1

Morphometric parameters according to body sides and genders. Data presented as mean (standard deviation).

Parameter	Body side		value^1	Gender		value^2
	Right	Left		Females	Males
Proximal LHBT length	137.9 (27.2)	138.9 (27.2)	0.8966	133.5 (27.5)	143.9 (25.7)	0.2418
Width of LHBT-belly junction	12.1 (4.2)	12.0 (4.2)	0.8776	12.1 (4.5)	11.9 (3.9)	0.9885
Thickness of LHBT-belly junction	2.3 (0.8)	2.2 (0.9)	0.6406	2.4 (0.8)	2.2 (0.9)	0.4210
Acc. LHBT length	60.7 (16.7)	58.6 (15.7)	0.6726	55.1 (17.1)	61.2 (15.7)	0.5913
Width of acc. LHBT-belly junction	3.3 (0.8)	3.4 (0.9)	1.0000	3.7 (0.4)	3.3 (0.9)	0.4779
Thickness of acc. LHBT-belly junction	1.5 (0.4)	1.6 (0.5)	0.8501	2.0 (0.3)	1.4 (0.4)	0.0421
Proximal SHBT length	81.7 (22.1)	80.2 (18.9)	0.9272	81.9 (20.3)	79.8 (20.8)	0.4437
Width of SHBT-belly junction	12.1 (4.5)	11.7 (4.5)	0.6790	12.3 (4.9)	11.5 (4.0)	0.9501
Thickness of SHBT-belly junction	2.3 (0.9)	2.1 (0.8)	0.2501	2.3 (0.7)	2.0 (1.0)	0.0770
Length of LHB	152.8 (25.9)	153.9 (28.0)	0.9673	140.7 (27.2)	166.4 (19.3)	0.0001
Length of SHB	165.5 (34.4)	164.2 (37.8)	0.9081	153.3 (30.4)	176.7 (37.5)	0.0005
Length of 3^rd head	94.7 (60.1)	105.3 (62.4)	0.6693	118.3 (44.6)	71.1 (72.2)	0.1232
Length of 4^th head	110.9 (28.6)	123.1 (39.9)	0.9273	125.4 (7.5)	108.2 (51.4)	0.2353
Length of 5^th head	111.1 (1.6)	110.2 (0.0)	0.6831	110.1 (0.2)	111.2 (1.4)	0.4142
Width of distal myotendinous junction	11.8 (3.2)	12.0 (3.5)	0.7020	10.8 (3.0)	12.9 (3.4)	0.0045
Thickness of distal myotendinous junction	3.2 (0.9)	3.3 (1.2)	0.7661	3.1 (1.2)	3.3 (0.9)	0.0751

¹The Wilcoxon test; ²The Mann–Whitney test.