Anatomic relationship of extensor indicis propius and extensor digitorum communis: Implications for tendon transfer

Table 1 Specimen demographics and measurements

Laterality	Age (yr)	Sex	Circumference at dER (mm)		Circumference at MCP (mm)		EIP distance from dER to myotendinous junction (mm)	Relationship of EIP to EDCI
			cEDCI	cEIP	cEDCI	cEIP	EIP
Left	52	M	8	15	12	14	29	EIP ulnar
Left	54	F	9	10	13	10	15	EIP ulnar
Right	38	M	12	13	12	12	16	EIP ulnar
Left	48	M	12	15	14	13	15	EIP ulnar
Right	54	F	11	11	13	9	14	EIP ulnar
Right	30	M	7	8	11	8	20	EIP ulnar
Left	24	M	11	12	9	10	18	EIP ulnar
Right	44	M	9	14	11	14	23	EIP ulnar
Left	38	F	9	8	10	9	27	EIP ulnar
Right	57	F	9	12	11	13	18	EIP ulnar
Right	19	M	8	9	10	10	2	EIP ulnar
Right	44	M	11	13	11	11	37	EIP ulnar
Left	30	M	7	5	14	9	22	EIP ulnar
Left	49	F	9	13	10	10	4	EIP ulnar
Left	19	M	9	9	8.5	11	2	EIP ulnar
Right	48	M	9	8	9	9	48	EIP ulnar
Right	48	M	8	14	12	14	25	EIP ulnar
Left	44	M	11	13	12	8	17	EIP ulnar
Right	24	M	10	14	13	12	13	EIP ulnar
Left	35	M	14	10	14	10	10	EIP ulnar
Left	20	M	9	11	10	8	2	EIP ulnar
Right	20	M	9	13	8	11	3	EIP volar
Left	20	F	10	7	11	8	10	EIP ulnar
Right	21	F	9	10	10	9	3	EIP ulnar
Left	40	M	7	11	10	8	24	2 slips of EIP ulnar
Right	49	F	7	8	11	11	4	EIP ulnar
Right	33	M	9	12	9.5	12	18	EIP ulnar
Right	20	F	9	10	9	8	6	EIP ulnar
Left	33	M	9	15	11	15	24	EIP ulnar
Average	36.4		9.3	11.1	11.0	10.6	16.2
Standard deviation	12.7		1.7	2.7	1.7	2.1	11.1

dER: Distal extensor retinaculum; MCP: Metacarpophalangeal; EIP: Extensor indicis proprius; EDCI: Extensor digitorum communis to the index; M: Male; F: Female.

Table 2 Measurements of extensor indicis proprius and extensor digitorum communis to the index tendons, segregated by gender

Sex	Age (yr) ± Std	Circumference at dER (mm) ± Std		Circumference at MCP (mm) ± Std		EIP distance from dER to myotendinous junction (mm) ± Std
		cEDCI	cEIP	cEDCI	cEIP	EIP
M	34.7 ± 11.1	9.5 ± 1.9	11.7±2.8	11.1 ± 1.8	11.0 ± 2.3	18.4 ± 11.8
F	40.2 ±1 5.8	9.1 ± 1.1	9.9 ± 2.0	10.9 ± 1.4	9.7 ± 1.6	11.2 ± 8.0
P value	0.28	0.56	0.09	0.77	0.14	0.11

Std: Standard deviation; dER: Distal extensor retinaculum; MCP: Metacarpophalangeal; EIP: Extensor indicis proprius; EDCI: Extensor digitorum communis to the index; M: Male; F: Female.