Craniocervical Instability in Ehlers-Danlos Syndrome—A Systematic Review of Diagnostic and Surgical Treatment Criteria

Abstract

Study Design Systematic review. Objective Ehlers-Danlos Syndrome (EDS) comprises a spectrum of connective tissue disorders, which may be associated with cranio-cervical instability (CCI). There is a lack of consensus on diagnostic imaging parameters, indications, and outcomes of surgical treatment. Methods This systematic review analyses the literature on diagnostic methods and/or criteria for CCI, screening the databases Ovid Medline, Embase, Cochrane Library, and PubMed. Articles were included based on the PRISMA guidelines and assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS) and according to their evidence level. Results Sixteen articles, including 78 surgical patients, met the inclusion criteria. The main diagnostic measures for CCI were dynamic x-rays and CT imaging. Ten different radiographic parameters were reported, of which 4 were the most frequently applied for surgical decision-making: the clivo-axial angle (CXA), the Harris measurement, the Grabb–Mapstone–Oakes measurement, and the angular displacement of C1 to C2. The evidence level ranged between III and V and the article quality between 4 and 8 out of 9 stars on the NOS Scale. Conclusions There is a lack of high quality, prospective evidence regarding the evaluation of suspected CCI in patients with EDS. Based on our systematic review, we recommend that the CXA, Harris measurement, Grabb–Mapstone–Oakes measurement, and the angular displacement of C1 to C2 be used to evaluate suspected CCI in EDS patients. Surgical fixation of suspected CCI should only be performed in cases with clear radiographic presence of instability and concordant symptoms/signs. Consensus-based guidelines and care pathways are required.

Treatment of Atlantoaxial Dislocation in Children with Down Syndrome Using Posterior Atlantoaxial Screw Fixation

“…More recently, others have reported on the importance of mechanical deformity, described in terms of both the kyphosis of the cranio-cervical junction and the amount of pathological translation. The former is measured as the clival axial angle, or CXA (less than 135 degrees is potentially pathological) and the latter translation is measured from the Harris/BAI measurement in flexion subtracting the Harris measurement in extension: a translation of >4 mm is considered ( 21 ). In short, the assessment of AOI is very difficult, especially for children, since the assessment often requires CT and MRI examinations of the dynamic position.…”

Presentation and physical therapy management of upper cervical instability in patients with symptomatic generalized joint hypermobility: International expert consensus recommendations

“…UCI may involve C0-C1 and/or C1-C2 joints, resulting in atlanto-occipital/craniocervical instability (AOI/CCI) and/or atlantoaxial instability (AAI) (1)(2)(3)(4). Signs and symptoms of AOI and AAI overlap and, while they can be differentiated radiologically (1,5), it is not always possible to differentiate them in the physical therapy clinic. Although physical/physiotherapists are likely to treat these patients, there are no published guidelines for safe, conservative assessment or management of UCI in this population (1,5,6).…”

“…Signs and symptoms of AOI and AAI overlap and, while they can be differentiated radiologically ( 1 , 5 ), it is not always possible to differentiate them in the physical therapy clinic. Although physical/physiotherapists are likely to treat these patients, there are no published guidelines for safe, conservative assessment or management of UCI in this population ( 1 , 5 , 6 ). Diagnosis based on history and physical exam can be challenging as presentation can be quite variable between patients and even in the same patient over time, ranging from mild discomfort to severe disability and objective neurological signs.…”

“…Symptoms of UCI include: headaches, neck or facial pain, dizziness, vertigo, nausea, paresthesias, dyspnea, dysphonia, vision changes (blurred or tunnel vision, visual aura), hearing changes, dysphagia, choking, sleep apnea, memory deficits, and pre-syncopal episodes. Signs associated with UCI include: long-tract findings such as hyper-reflexia, positive Babinski and Hoffman’s signs, loss of abdominal reflex, dysdiadochokinesia, as well as bowel/bladder problems, gait/balance deficits, weakness of arms and legs, sleep apnea and syncopal episodes ( 1 , 5 , 8 ). Dysautonomia is more likely to be present and severe with UCI and cervical myelopathy ( 9 , 10 ).…”

“…Mild UCI in S-GJH may be relatively common (52–66%); ( 10 , 11 ) while severe UCI is uncommon (5%) ( 11 ), it can be debilitating ( 8 ). UCI is likely underdiagnosed in S-GJH ( 5 , 11 ). UCI in S-GJH has been the topic of several recent publications discussing imaging studies and surgical management.…”