Inter-examiner reliability of radiographic measurements from Open-mouth lateral bending cervical radiographs.

BACKGROUND: Following head and neck trauma, the involvement of the cranio-cervical junction (CCJ) and its contribution to a patients transition to chronic pain, is poorly understood. The detection of hypermobility in this region is dependent on clinical examination and static imaging modalities such as x-ray, CT and MRI. Sagittal plane hypermobility of the CCJ is evaluated using saggital view, flexion-extension cervical radiographs. Frontal plane hypermobility is typically assessed using lateral bending and open mouth cervical radiographs. Unfortunately there is no established reliability surrounding the use of these measures. This study explores the reliability of radiographic measurements of lateral-bending open-mouth cervical radiographs. METHODS: Cervical open-mouth lateral-bending X-ray images were collected from 56 different patients between 18 and 60 years of age patients following cervical spine injury. These images were interpreted by two musculoskeletal radiologists and two clinicians (physiatrist and chiropractor), using a standard set of measurements. Measurements included qualitative and quantitative assessments of the amount of asymmetry noted between various osseous landmarks. Reliability statistics were calculated for levels of agreement using kappa coefficients (κ) and Intraclass Correlation Coefficients (ICC) for dichotomous and continuous variables, respectively. RESULTS: Reliability (κ) for qualitative assessments were moderate to substantial for asymmetry of neutral C2 spinous position, dens-lateral mass spacing, and "step off" between the lateral borders of the articular pillars of C2 and C1 lateral mass (κ range = .47-.78). ICC values for the quantitative measurements of dens-lateral mass spacing and "step off" between the lateral borders of the C2 articular pillars and C1 lateral mass were moderate to excellent (ICC range = .56-.97). CONCLUSIONS: The qualitative and quantitative measurements used in this study demonstrated good to excellent inter-examiner reliability. Correlation with clinical findings is necessary to establish the utility of these measurements in clinical practice.

Utility of the anesthetic test dose to avoid catastrophic injury during cervical transforaminal epidural injections.

BACKGROUND CONTEXT: Reports of serious complications from cervical transforaminal epidural corticosteroid injections often consider accidental intra-arterial injection the most likely mechanism of injury. As a result, many physicians have instituted methods to prevent intravascular injections. Routine use of the anesthetic test dose is one such method. The utility of the anesthetic test dose in this function has not been characterized in the current literature. PURPOSE: The aim of this study was to determine the utility of injecting an anesthetic test dose before cervical transforaminal epidural corticosteroid injection and estimate the rate of false-negative intravascular contrast injection using live fluoroscopy and digital subtraction angiography (DSA). STUDY DESIGN: Two-center retrospective study. PATIENT SAMPLE: A consecutive cohort of men and women, ages of 23 to 83, who underwent cervical transforaminal epidural injection and received the anesthetic test dose after contrast injection was negative for vascular uptake, observed using live fluoroscopy or DSA. OUTCOME MEASURES: Response to the anesthetic test dose was documented in each procedure note and recorded as either positive or negative. METHODS: Records of three physiatrists at two academic spine centers (Center A and Center B) were reviewed to identify all patients who received a cervical transforaminal epidural injection during the preceding 5 years, resulting in a cohort of consecutively treated patients at each center. Each patient record was reviewed for demographics, indication for injection, procedure level and side, needle gauge, use of DSA, volume and type of anesthetic test dose used, and result of test dose injection. The test dose was considered positive if the following occurred: agitation or other sudden central nervous system change; gross motor deficits and/or paresthesias in the trunk, legs, or contralateral arm; systemic symptoms of anesthetic toxicity including cardiac arrhythmia, perioral numbness, metallic taste, dizziness, and/or ringing in the ear. For analysis, injections were separated into groups to compare results at Center A to Center B and to compare injections that used DSA to those that did not. The incidence of a positive response was calculated as a percentage from the total number of injections in the group. Differences between groups were analyzed for statistical significance using the Fisher exact test. RESULTS: Six hundred seventy-eight injections were included. Of these, 349 were performed at Center A with test doses given after contrast injection under live fluoroscopy. The remaining 329 were performed at Center B, 183 also using live fluoroscopy, and 146 using DSA. The overall incidence of a positive anesthetic test dose was 0.59% (4/678). There was no significant difference between the incidence at each of the two centers (0.86% [3/349] vs. 0.30% [1/329]; p=.63). The overall incidence after live fluoroscopy was 0.75% (4/532) and after DSA was 0% (0/146), but this difference was not statistically significant (p=.58). Positive symptoms elicited by test dose administration included midneck and contralateral arm pain, metallic taste, dizziness, tachycardia, full body paresthesias, auditory changes, slurred speech, and motor ataxia. In all four cases with a positive response, the procedure was immediately terminated, symptoms resolved, and no lasting complications were observed. CONCLUSIONS: The routine use of an anesthetic test dose appears to be safe and capable of detecting potentially dangerous intravascular injections undetected by conventional techniques. Positive responses occur in a small portion of those who receive the test dose injection. Further studies are required to determine the optimal dose and concentration of anesthetic to be used and the time required for observation after test dose administration.