Cervical instability in patients with Trisomy 21: The eternal gamble

Patients with Trisomy 21 are particularly at risk of cervical instability due to ligamentous laxity and osseous abnormalities. Up to 30% of Trisomy 21 patients are affected by atlanto-axial or atlanto-occipital instability, but only 1%-2% of cases are symptomatic. The radiologic assessment of cervical instability is not unanimously considered mandatory. The dynamic cervical spine radiograph is the most common screening tool for ruling out cervical spine instability in patients with Trisomy 21, and it is often requested before surgery. Several measurements have been investigated to assess the presence and degree of cervical instability; however, no conclusive recommendations have been forthcoming. In daily practice, many anesthesiologists may provide anesthesia via such means as laryngoscopy and tracheal intubation during surgery, without any radiological investigations before surgery. This review focuses on the diagnostic and prognostic measures available to evaluate the presence and degree of cervical instability in patients with Trisomy 21 and to propose practical recommendations to be applied in clinical practice.