Objective: To study the distribution of intramuscular nerve branches

muscle spindles and nerve entering points in human sartorius and rectus femoris(RF) and to provide morphological data for clinical surgery.Methods: The morphological characteristics of sartorius and RF were studied by using the gross-anatomy.The locations of the nerve entering points to muscles were ascertained by measuring.HE staining technique and stereology method were used to study the two muscles’ spindle distribution.Modified Sihler’s neural staining technique was used to observe the two muscles’ intramuscular nerve branch pattern.Results: Sartorius was a kind of ribbon muscle which was composed of long fascicle arranged parallel.RF was a kind of penniform muscle which was composed of short fascicle.The muscle spindle average densities of sartorius and RF were 38.04 number/g and 19.38 number/g

respectively.Sartorius had 2 primary branches entering the muscle and distributed to upper part and middle-lower part

respectively.RF had 2 primary branches and distributed to lateral-upper part and medial-lower part

respectively.The nerve entering points in sartorius laid(9.75±1.30) cm

and in RF laid(10.23±0.97) cm and(14.48±1.12) cm below anterior superior iliac spine

respectively.Conclusion: Sartorius is a ribbon muscle

but RF is a penniform muscle.Sartorius and RF both have two primary branches

respectively.There are less intramuscular nerve branches and less anastomoses and more obvious regional distribution in sartorius.The nerve entering points in sartorius and RF centralize mainly in the No.2 region of the front upper part of thigh.