CERVICAL DYNAMIC SCREENING IN SPINAL CLEARANCE – NOW HISTORICALLY REDUNDANT

Abstract

Background: The safest and most effective method of early spine clearance in unconscious patients is the subject of intense debate.

Hypothesis: Helical CT is a sufficiently sensitive investigation to render dynamic screening of the cervical spine redundant.

Protocol: Our protocol for cervical spinal clearance in the unconscious patient since April 1994 involves the use of plain radiographs, CT scan (helical CT since 1997) and dynamic screening (DS).

Method: Over a ten-year period, April 1994 to September 2004, 839 patients were admitted to intensive care under the orthopaedic surgeons. 35 patients were excluded because of incomplete records.

Results:

• Demographics: The mechanism of injury was a road traffic accident in 80% and the mean ISS was 24.1. There were 95 patients (10.9%) with a cervical spine fracture, 96 (10.8%) with a fracture in either / both thoracic and lumbar regions.

• Spine clearance: Mean intubation (7.1 days), time to spine clearance (mean 0.4 days). In 318 patients, clearance was performed with the patient conscious (284 prior to intubation, 34 after intubation of < 24hrs). 42 patients (4.6%) died before spine clearance. In 10 patients, the protocol was not followed.

• Inclusions: 434 patients underwent CT. 10 of the 95 cervical fractures were deemed stable and underwent DS (n = 349).

• Missed Cases: CT missed 2 cases of instability, one of these (an atlanto-occipital dislocation) was also missed by DS. Critical analysis revealed a Powers ratio calculation would have diagnosed this injury on CT. Sensitivity (CT 97.7% vs DS 98.8%), specificity (100% CT and DS). There were no complications from either procedure.

Conclusion: DS is a safe procedure but has no real advantage over helical CT. Power’s ratio calculation is essential to reduce the chance of a missing an upper cervical injury. The cervical spine can be reliably cleared using helical CT alone.