This study was undertaken to identify the sensory nerve endings in the
monkey hip joint capsule. The capsules from six monkeys were stained
in bulk by using a modified gold chloride method. Three morphologicall
y distinct nerve endings: Type I, II and IV receptors resembling Ruffi
ni end organs, Pacinian corpuscles and free nerve endings, respectivel
y, were identified. The results showed that the hip joint capsules wer
e densely innervated. Based on the present findings it is suggested th
at the monkey hip joint capsule is endowed with several types of affer
ent nerve endings, thus providing the anatomical basis for discriminat
ing afferent outflow to the central nervous system. (C) 1998 Wiley-Lis
s, Inc.