Routine imaging for anterior cervical decompression and fusion procedures: a survey study establishing current practice patterns

A retrospective cohort analysis of the effects of renin-angiotensin system inhibitors on spinal fusion in ACDF patients

BACKGROUND CONTEXT

Recently, preclinical and clinical studies suggest an association between renin-angiotensin system (RAS) blockers and bone healing, particularly in the context of osteoporotic bone fractures.

PURPOSE

To determine the correlation between the use of RAS inhibitors and fusion outcomes and neurologic status in anterior cervical discectomy and fusion (ACDF) surgery.

STUDY DESIGN

Retrospective observational study.

PATIENT SAMPLE

Patients who underwent ACDF for degenerative disorders.

OUTCOME MEASURES

Spinal fusion status and neurologic function (modified Japanese Orthopedic Association [mJOA] and Nurick grading scales).

METHODS

A retrospective chart review was performed, including 200 patients who underwent ACDF for degenerative disorders with 1-year minimum follow-up. Demographic data, comorbidities, antihypertensive medication, neurologic examination, and fusion status were collected. Spinal fusion was assessed via plain cervical x-ray, resorting to dynamic radiographs and/or computer tomography (CT) in cases of uncertainty. Preoperative mJOA and Nurick scores and recovery rates were calculated to determine neurologic status.

RESULTS

Of the 200 patients (42.5% females, 57.5% males, median age of 53.7 years), 82 hypertensive patients were identified. Seventy-seven (93.9%) were taking antihypertensive medication as follows: 36.4% angiotensin-II receptor blockers (ARBs), 35.1% angiotensin-converting enzyme inhibitors (ACEIs), and the remaining patients were taking other medication. In the analysis of fusion rates, patients treated with ARBs exhibited a higher fusion rate, while those treated with ACEIs displayed a lower fusion rate compared to untreated nonhypertensive patients (p = .04 and .02, respectively). The difference in fusion rates between ARBs and ACEIs was also significant, with the former displaying higher rates (p < .001). Smoking exhibited a negative correlation with spinal fusion (p < .001). In the multivariate analysis, ARBs remained an independent factor for successful fusion (p = .02), while smoking remained a risk factor for failed fusion (p = .002). In the neurologic examination, ACEIs, hypertension status, and older age correlated with lower modified Japanese Orthopedic Association (mJOA) recovery rates (p = .001, <.001, and <.001, respectively) in the univariate analysis.

CONCLUSIONS

In ACDF patients, we observed that ARBs were associated with higher fusion rates. Conversely, ACEIs and smoking were related to failed fusion. Prospective case-control studies are needed to confirm these RAS inhibitors effects on spinal fusion.

Decreasing radiation dose with FluoroLESS Standalone Anterior Cervical Fusion

Background

Radiation dose continues to be a concern especially in the field of spine surgery, where anterior and posterior instrumentation is frequently utilized to treat multiple pathologies. The authors aim to demonstrate the feasibility of decreasing the radiation dose in standalone anterior cervical discectomy and fusion (ACDF).

Methods

Standalone ACDF (S-ACDF) with 48 consecutive patients (Group 1) with a comparison control group with ACDF with an anterior cervical plate (ACP) of 49 patients (Group 2). Fluoroscopy was performed for positioning, identification of level, placement of the implant, each screw, final AP and lateral images for the first 20 patients in Group 1. Screw placement could then be performed confidently based on cosine rule of cosine (Ѳ) = adj/hyp.

Results

Forty-eight patients in Group 1 (S-ACDF) and 49 patients in Group 2 (ACDF-ACP). Statistical significance not demonstrated for age, BMI or gender, P=0.691, 0.947 and 0.286 respectively. Mean radiation dose in group 1 of 17.9±6.6 mAs and 0.8±0.3 mSv was significantly less compared to group 2 which was 29.8±5.4 and 1.3±0.2 mSv, P<0.001. The average radiation dose for single-level fusion in Group 1 was 12.5±3.5 mAs and 0.5±0.1 mSv this is compared to Group 2 of 27.8±3.9 mAs and 1.2±0.2 mSv, P=0.001. The average radiation dose for two level fusion in Group 1 was 22.2±5.1 mAs and 0.9±0.2 mSv this is compared to Group 2 of 33.9±6.0 and 1.4±0.3 mSv, P=0.001.

Conclusions

In the outpatient setting, S-ACDF has shown a statistically significant intergroup difference in overall radiation dose, as well as single and two-level fusions, (P<0.001). We conclude that S-ACDF can decrease overall radiation exposure to patients.

Anterior cervical discectomy and fusion: review and update for radiologists

OBJECTIVES

The goals of this article are to describe the various types of interbody grafts and anterior cervical plating systems, techniques for optimizing evaluation of cervical spine metallic implants on CT and MR imaging, expected appearance and complications of ACDF on postoperative imaging and imaging assessment of fusion. Optimization for optimizing metal induced artifacts.

CONCLUSION

Currently, ACDF is the most commonly performed surgical procedure for degenerative cervical spine disease. Interbody fusion is performed with bone grafts or interbody spacers, and may be supplemented with anterior cervical plating. Compressive pathologies at the vertebral body level may be addressed by simultaneous corpectomy. Postoperatively, imaging plays an integral role in routine screening of asymptomatic individuals, fusion assessment and evaluation of complications.

Intermittent Feet Dorsiflexion as a Simple Trick to Improve Cervical Fluoroscopic Visualization

BACKGROUND

Anterior cervical surgery is routinely performed using fluoroscopy. Visualizing the lower cervical levels can be challenging, particularly in obese, muscular, and broad-shouldered patients. We found that grabbing both feet of the patient at the level of the metatarsals and cranially pushing the feet, creating dorsiflexion at the ankle joints, seems to increase the number of fluoroscopically visualized cervical levels. We aimed to measure the average change in fluoroscopically visualized levels when performing this maneuver.

METHODS

In 10 consecutive patients undergoing an anterior cervical discectomy and fusion procedure, we counted the number of fluoroscopically visualized cervical levels. Visible cervical levels in lateral fluoroscopic cervical images that were taken with and without the execution of the aforementioned maneuver were counted by 2 blinded observers.

RESULTS

Performing this maneuver added on average almost 1 vertebral body height to the fluoroscopic image. The additional number of fluoroscopically visible cervical levels was significantly higher in patients <50 years old but was not affected by sex or body mass index.

CONCLUSIONS

We propose a simple, convenient, and effective technique to increase the number of visualized cervical levels on lateral cervical fluoroscopy. This maneuver may have some advantages compared with other commonly used techniques.

Utility of Computed Tomography following Anterior Cervical Diskectomy and Fusion

Study Design Retrospective case series. Objective To assess the utility of postoperative computed tomography (CT) following anterior cervical diskectomy and fusion (ACDF) and to determine the clinical circumstances most likely to lead to an abnormal CT scan. Methods Patients who underwent ACDF at a tertiary center over a span of 5 years were investigated. Only patients who had a minimum of 6 months' postoperative follow-up and a CT within 2 years after the surgery were included in the study group. All the postoperative notes were reviewed to determine indications for the CT, abnormalities identified, and whether the scan led to an alteration in the treatment course. Results The charts of 690 patients who underwent ACDF were reviewed. Of the 690 patients, 45 (7%) had postoperative CTs. These patients accounted for 53 postoperative CT scans, 45 (85%) of which were taken for patients who expressed persistent postoperative symptoms and/or had abnormal imaging. There were no indications for 8 (15%) of the CTs. Patients who had a CT for persistent symptoms and/or abnormal preliminary imaging were significantly more likely to have an abnormal CT (p = 0.03) and/or an alteration in treatment course (p = 0.04) compared with those with no symptomatic or radiologic indication for CT. Conclusions CT is associated with minimal utility regarding the alteration of treatment course when employed in asymptomatic patients. Postoperative CT should be ordered solely for symptomatic patients or those with other abnormal preliminary imaging. Judicious use of postoperative CT will limit the radiation exposure and cost.

Routine imaging after operatively repaired distal radius and scaphoid fractures: a survey of hand surgeons

Background There is currently no standard of care for imaging after hand and upper-extremity procedures, and current imaging practices have not been characterized. Questions/Purposes To characterize current imaging practices and to compare those practices to the best available evidence. Patients and Methods A survey was distributed to attending-level surgeons at a regional hand and upper-extremity surgery conference in the United States in 2013. 40 out of 75 surgeons completed the survey (53%). Results All results are presented for distal radius and scaphoid fractures, respectively. There was a high degree of variability between respondents in the number of radiographic series routinely ordered during follow-up of asymptomatic patients, with the number of series ranging from 1-6 and 1-6. On average, respondents did not order an excessive number of follow-up radiographs for asymptomatic patients, with means (± standard deviations) of 2.6 ± 1.0 and 3.3 ± 1.2 radiographic series. Radiographic series were taken at only 74% and 81% of postoperative visits with asymptomatic patients. Only 10% and 8% of respondents felt it was acceptable medical practice to save costs by ordering postoperative radiographs only when patients are symptomatic. Conclusions Among a sample of 40 fellowship-trained hand surgeons, these findings demonstrate a high degree of variability in number of radiographs obtained after operative repair of distal radius and scaphoid fractures. On average, respondents were relatively efficient with respect to total number of postoperative radiographs ordered. Level of Evidence Diagnostic study, level IV.

Methods of evaluating lumbar and cervical fusion

Introduced in 1911, spinal fusion is now widely used to stabilize the cervical, thoracic, and lumbar spine. Despite advancements in surgical techniques, including the use of instrumentation and optimizing bone graft options, pseudarthrosis remains one of the most significant causes of clinical failure following attempted fusion. Diagnosis of this common complication is based on a focused clinical assessment and imaging studies. Pseudarthrosis classically presents with the onset of or return of axial or radicular symptoms during the first postoperative year. However, this diagnosis is complicated because other diagnoses can mimic these symptoms (such as infection or adjacent segment degeneration) and because many cases of pseudarthrosis are asymptomatic. Computed tomography and assessment of motion on flexion/extension radiographs are the two preferred imaging modalities for establishing the diagnosis of pseudarthrosis. The purpose of this article was to review the current status of imaging and clinical practices for assessing fusion following spinal arthrodesis.