Spinophorosaurus and some other sauropodomorphs did not have reduced vestibular apparatuses, a sensory system for balance and orientation in the inner ear, though this might have been expected in a lineage that led to heavy, plant-eating quadrupeds.
It is unknown why Spinophorosaurus retained this feature, but the size and morphology of sauropodomorph labyrinths may be related to neck length and mobility, for example.
It is possible expansion of the vestibular apparatus is an indicator of the importance of vision and coordinated eye, head, and neck movements, though interpretation of sauropod vestibular features are still uncertain.

At a 2018 conference, Benjamin Jentgen-Ceschino and colleagues reported radial fibrolamellar bone (RFB), a type of bone tissue characterised by radially oriented channels, in the outermost part of the cortex (the outermost bone layer) of the humerus belonging to an adult Spinophorosaurus specimen and a young adult Isanosaurus.
Normally, the cortex in the long bones of sauropods shows a fibrolamellar complex instead.
RFB is considered to be fast growing bone tissue, and has not been reported in sauropods before.
Its presence in the outermost cortex is unusual, as it would usually be expected in the innermost cortex (corresponding to juvenile growth).
The RFB of the Spinophorosaurus was buried in the outer cortex, followed by a normal fibrolamellar complex, which indicates the animal survived for some time after its accelerated growth, which probably suggests pathological bone growth due to injury.
Spinophorosaurus and some other sauropodomorphs did not have reduced vestibular apparatuses, a sensory system for balance and orientation in the inner ear, though this might have been expected in a lineage that led to heavy, plant-eating quadrupeds. It is unknown why Spinophorosaurus retained this feature, but the size and morphology of sauropodomorph labyrinths may be related to neck length and mobility, for example. It is possible expansion of the vestibular apparatus is an indicator of the importance of vision and coordinated eye, head, and neck movements, though interpretation of sauropod vestibular features are still uncertain.
At a 2018 conference, Benjamin Jentgen-Ceschino and colleagues reported radial fibrolamellar bone (RFB), a type of bone tissue characterised by radially oriented channels, in the outermost part of the cortex (the outermost bone layer) of the humerus belonging to an adult Spinophorosaurus specimen and a young adult Isanosaurus. Normally, the cortex in the long bones of sauropods shows a fibrolamellar complex instead. RFB is considered to be fast growing bone tissue, and has not been reported in sauropods before. Its presence in the outermost cortex is unusual, as it would usually be expected in the innermost cortex (corresponding to juvenile growth). The RFB of the Spinophorosaurus was buried in the outer cortex, followed by a normal fibrolamellar complex, which indicates the animal survived for some time after its accelerated growth, which probably suggests pathological bone growth due to injury.
Spinophorosaurus