We can envisage the skull, in simple terms, as ball sitting on top of a pipe, the latter representing the spinal columnThe individual bones that we call vertebrae, when joined together by several ligaments, make of the spinal, or vertebral column.. We refer to the point where the two join together as the craniovertebral junctionThat part of the body where the base of the skull is joined to the top of the spine. Inside these bony enclosures, the craniovertebral junction is also where the brain stem continues downwards as the spinal cord.. Normally the shape of this junction is like a funnel, with the lower part of the cerebellumThis word means the “little brain” and refers to a large part of the brain that sits in lowermost part of the skull, at the back of the head, immediately above the top of the spine. This part of the skull is known as the posterior fossa. sitting in the mouth of the funnel and the cervicalThe word cervix means neck. We all have a neck, holding up our head. Ladies, in addition, have a neck (cervix) to their womb. The word cervical therefore refers to the neck. Ladies, at a certain age, are offered cervical screening – formerly known as smear tests. People with neck problems are sometimes given a collar to wear, commonly referred to as a cervical collar, although this is an unnecessary duplication of words; where else would a collar be worn? part of the spinal cordThe main nerve trunk running down the spinal canal and connecting the individual’s mind and consciousness to the rest of his or her body. It is about the size of a person’s little finger, in diameter. It cannot repair itself if damaged. being in the stem. The term basilar invagination describes an anatomical state where the “pipe” (i.e. the uppermost part of the spinal columnThe individual bones that we call vertebrae, when joined together by several ligaments, make of the spinal, or vertebral column.) is pushed up into the lower half of the “ball” (i.e. the posterior fossaThat part of the cranial cavity that lies below the tentorium and which contains the brain stem and the cerebellum. of the cranial cavity). This results in a distortion of the normal bony anatomy at the craniovertebral junctionThat part of the body where the base of the skull is joined to the top of the spine. Inside these bony enclosures, the craniovertebral junction is also where the brain stem continues downwards as the spinal cord.. This sometimes (but not always) causes some physical distortion of the brain stemThis is the most primitive part of the brain, connecting the rest of the brain to the body, via the spinal cord. In addition to feeding signals to and from such “higher centres”, the brain stem contains a number of important control centres, regulating vital functions such as breathing and blood pressure., which may lead to the development of neurological symptomsThese include disturbances of motor functions (e.g. power, strength & co-ordination), alterations of body senses (e.g. sight, hearing or touch) and changes in consciousness (e.g. blackouts or seizures).. Basilar invagination may develop secondary to certain rare disorders that lead to softening of bone but, more often, they are seemingly just the way that the individual is made. Read more