The pectoral girdle or shoulder girdle is the set of bones which connects the upper limb to the axial skeleton on each side. It consists of the clavicle and scapula in humans and, in those species with three bones in the pectoral girdle, the coracoid. Some mammalian species (e.g. the dog and the horse) have only the scapula.
In humans, the only true anatomical joints between the shoulder girdle and axial skeleton are the sternoclavicular joints on each side. No anatomical joint exists between each scapula and the rib cage; instead the muscular connection or physiological joint between the two permits great mobility of the shoulder girdle compared to the compact pelvic girdle — i.e. because the upper limb is not usually involved in weight bearing, its stability has been sacrificed in exchange for greater mobility.
In those species having only the scapula, no joint exists between the forelimb and the thorax, the only attachment being muscular.
Other articles related to "pectoral girdle":
... The pectoral girdle is discussed by Chatterjee as being highly derived in Protoavis, displaying synapomorphies of Ornithothoraces, including the presence of a hypocleidium-bearing furcula, and a hypertrophied ...
... It is known from a fragmented skull, the left side of the pectoral girdle, and the entire right forelimb and right hindlimb along with a few belly scales ... The fossil fragments also indicate that its head was disconnected from the pectoral girdle ... absence of the rough postbranchial lamina of the pectoral girdle, it has been determined that Tulerpeton had no gills and was therefore entirely dependent on ...
... Costochondral joints Interchondral joints Joints of upper limb Joints of pectoral girdle Syndesmoses of pectoral girdle Coraco-acromial ligament ...
Famous quotes containing the word girdle:
“There are no stars to-night
But those of memory.
Yet how much room for memory there is
In the loose girdle of soft rain.”
—Hart Crane (18991932)