Craniocervical Instability & Ehlers-Danlos Syndrome
Updated: Apr 28
Over the last decade of clinical practice working with clients with Ehlers-Danlos Syndrome (EDS), and hypermobility spectrum disorders has thought me that not only the approach to the multiple joint hypermobility, tissue fragility, and chronic pain are important but also the patient’s physical, nutritional and psychological challenges. IT has also showed me that there is a major correlation of EDS and CCI.
Craniocervical Instability (CCI) is when the ligaments in the upper cervical spine become loose, which can lead to headaches, migraines, Orthostatic Intolerance (difficulty with upright postures), difficulty swallowing, blurred vision, and neck pain. It may involve C0-C1 and C1-C2 joints, and it results in a tanto-occipital, craniocervical instability (AOI/CCI) and/or atlantoaxial instability (AAI).
Mild upper cervical instability (UCI) is common on patients with symptomatic joint hypermobility and it can have a significant impact in the quality of life of these patients.
Less common, sever UCI can potentially be debilitating, and it includes both Atlanta-occipital and atlantoaxial instability.
Many EDS clients will present with altered sensoriomotor function, affected by neurological and spinal manifestations from cervical instability. (I.e. Craniocervical instability (CCI), Arnold Chiari Malformation, Upper Cervical Ligament Laxity). Commonly associated symptoms among patients with CCI include neck/face pain/stiffness, heaviness of controlling head or feeling bobbleheaded , blurry vision, dizziness, headache, sleeping disorder, hearing impairment, speech impairment, swallowing problems, lnausea, chocking for no apparent reason, memory deficits, brain fog, loss of balance, and in among others.
SIgns and findings commonly seen on these patients are hyper-reflexiva, Babinski and Hoffman's sign, loss of the abdominal reflex, dysdiadochokinesia (inability to defined as the inability to perform rapid alternating muscle movements), as well as bowel and bladder problems, gait,balance deficits, weakness to the arms and legs, sleep apnea, and syncopal episodes.
There is a lot of confusion on the accepted test for diagnosis of these upper cervical pathologies, however not all types of images are suitable for the diagnosis. Each image test has a specific role in the diagnosis of CCI, Upright seated flexion/extension MRI helps on the diagnosis of horizontal inatbility, while a CT Scan with rotation is indicated on the diagnosis of rotational instability. In the case that vertical instability is suspected anInvasive cervical traction (ICT) with fluoroscopy can be of great assistance. The Digital Motion X-Ray has also been increasing in popularity, however, it is still not considered the gold standard for the diagnosis. Unfortunately a regular MRI or MRI of the cervical spine woth contrast will not diagnose CCI.
Once the test is done the following measurements should be considered: Clivo-Axial Angle (CXA), Grab Oaks, Basion-Axial Interval (BAI), Basion-Dens Interval BDI), Translational BAI, Translational BDI, dynamic BDI, and Dens over Chamberlain. In some cases manual traction, halo and invasive traction may be used. Symptomatic improvement with traction can help determine wether a patient with abnormal measurements will benefit fromcarniocervical fusion surgery.
It is important to understand that segment hypermobility, mechanical instability and functional instability are related but different. Hypermobility refers to excessive physiological motion of a joint for a persons' age, sex, and race. Mechanical Instability or laxity, reefers refers to excessive accessory motion at a joint, sometime leading to subluxation, giving way, or dislocation. Functional Instability refers to the subjective experience that joints may subluxation, give way or cannot be trusted, and is due to insufficient neuromuscular control at the joint.
Craniocervical Instability is a complex diagnosis, that is still poorly understood by the medical community and requires a speacilized physician and physical therapist to access and treat patients that present with positive imaging test. Always make sure you consult a medical specialist for proper diagnosis and treatment. This material is for educational purposes and doesn't intent to diagnose or treat any health problems.