Histological study of fabella and muscle origin of the plantaris and gastrocnemius lateral head in late-stage fetuses

摘要

Cartilaginous fabella appears to be embedded in the plantaris origin(PL)that fuses with the gastrocnemius lateral head(GL)in midterm fetuses.Histological sections of unilateral knee joints of 15 late-stage fetuses,we reexamined the topographical anatomy of fabella or its analogue(a tight fibrous mass)with origins of the GL and PL.Irrespective of whether the cartilaginous fabella is present(6/15)or absent,these muscle origins were composed of three parts(PLl,PL2 and PL3;GLl,GL2 and GL3).Fabella or its analogues embedded in a thicker common tendon origin of GL and PL.PL1 was similar to the adult PL,and originated from the femoral condyle immediately above the common tendon.