Retroflex odontoid Basilar Invagination/CCi/ filum sectioning

hi,
I wonder can anyone help I have retroflex odontoid, ? Basilar invagination confirmed Chiari malformation, small thoracic syrinx and a lot lumbar spine problems. I am awaiting rheumatologist and upright imaging to confirm the retroflex odontoid and basilar invagination ? CCI/AAI. I waiting an appointment with a Rheumatologist to check re possibility of EDS.I strongly suspect myself that I have EDS and occult tethered cord
I am wondering if anyone has any idea if surgery for CCI and Odontoid should be done before filum sectioning???Badly looking for any advice,
also if anyone has Basilar invagination or retroflex odontoid along with the Chiari would love to hear from you,in a very bad way with symptoms.
Thanks

I do not have basilar invagination but have a retroflexed dens- from what I have been told, surgery to “shave” down dens bone is “hyper-aggressive” and very risky due to proximity to brainstem. I only have 1mm space between dens/ brain stem- that isn’t much, so they’ve elected not to do surgery on dens. Every case is, of course, different- EDS is important to know because it affects healing after surgery. You can also google “beighton scale” test and do your own assessment, and then bring that info to rheumatologist/genetics doc. I am unaware of filum sectioning- sorry I can’t reply to that. Chair/CCI/retroflexed dens= Complex Chiari. Google youtube, Dr Henderson (“Think-tanks”) on Chiari/complex Chiari. He’s considered the gold standard of chiari doctors.