[Comparison of the Latissimus dorsi insertions on the iliac crest in chimpanzee (Pan troglodytes) and in man].
BACKGROUND
Comparing to other primates, one of the most important specificities of the human anatomy are consequences of bipedalism. Although bone consequences are well known (lumbar lordosis, horizontal position of the foramen magnum, lengthening of the lower limbs, reduction of the pelvis, specialization of the foot), consequences of our locomotion on the Latissimus dorsi are still unclear.


METHODS
One dissection of a chimpanzee Latissimus dorsi (Pan troglodytes) has been performed and compared to 30 human Latissimus dorsi dissections (10 fresh cadavers and 20 formoled cadavers). In each dissection, the existence of direct muscular insertions on the iliac crest has been investigated and the constitution of the thoracolumbar fascia has been described.


RESULTS
In chimpanzee dissection, a muscular direct insertion of the Latissimus dorsi was present on the iliac crest of 9 cm long. The TLF was made of the superficial and the deep fascias of the Latissimus dorsi and the superficial fascia of the erector spinae muscles which was deeper. In man, there was no direct muscular insertion of the Latissimus dorsi in 90 % of cases, the TLF was constituted the same way.


CONCLUSIONS
This study suggests that the Latissimus dorsi has been separated from the iliac crest in man during the evolution because of the permanent bipedalism and that it stayed inserted on the iliac crest in chimpanzee because of the brachiation.
Anatomie, faculté de médecine Paris-Diderot (Paris VII), service de chirurgie maxillo-faciale et stomatologie, hôpital Beaujon, AP-HP, 92110 Clichy, France. Electronic address: christian.vacher@bjn.aphp.fr.
C
C
Vacher
Anatomie, faculté de médecine Paris-Diderot (Paris VII), service de chirurgie maxillo-faciale et stomatologie, hôpital Beaujon, AP-HP, 92110 Clichy, France.
S
S
Ben Hadj Yahia
Laboratoire d'anatomie, faculté de médecine, université Nancy 2, 54000 Nancy, France.
M
M
Braun
Service de chirurgie orthopédique infantile, CHU de Nancy, 54000 Nancy, France.
P
P
Journeau
D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D002102:Cadaver; D004210:Dissection; D005260:Female; D006801:Humans; D007085:Ilium / Q000033:anatomy & histology*; D008297:Male; D002679:Pan troglodytes / Q000033:anatomy & histology*; D064171:Superficial Back Muscles / Q000033:anatomy & histology*
Anatomie comparée; Chimpanzee; Chimpanzé; Comparative anatomy; Crête iliaque; Fascia thoraco-lombal; Iliac crest; Latissimus dorsi; Thoracolumbar fascia