Selective cervical nerve root blockade: prospective study of immediate and longer term complications

BACKGROUND AND PURPOSE

Selective cervical nerve root blockade (SCNRB) is a useful procedure for evaluating and treating patients with cervical radiculopathy. Reports of complications related to injections within the cervical nerve root foramen have raised serious doubts regarding the safety of this procedure. This study was performed to prospectively evaluate the safety of fluoroscopically guided outpatient diagnostic and therapeutic SCNRB.

MATERIALS AND METHODS

Eight hundred two consecutive fluoroscopically guided diagnostic and/or therapeutic SCNRBs in 659 patients were performed during a 14-month period (November 2006-December 2007) at affiliated outpatient imaging centers. Each examination was performed by 1 of 8 experienced procedural radiologists by using an anterior oblique approach, with the needle position confirmed with radiographic contrast before injection of an admixture of local anesthetic and steroid. All patients were assessed immediately and at 30 minutes following the procedure. Additionally, 460 patients were called by telephone 30 days following the procedure. All complications were recorded.

RESULTS

Of the 802 attempted procedures, 799 were successfully completed. Three procedures were aborted due to anxiety, challenging body habitus, or persistent venous opacification observed during contrast injection and despite needle repositioning. There were no serious complications, such as stroke, spinal cord insult, permanent nerve root deficit, infection, or significant hematoma. There were 33 minor complications occurring within 30 minutes of the procedure; the most common was vasovagal symptoms. Three hundred forty-five patients were successfully contacted by telephone at 30 days postinjection, 9 of whom reported increased or new pain symptoms.

CONCLUSIONS

With our technique, fluoroscopically guided SCNRB is a safe outpatient procedure with a low immediate and delayed complication rate.

Selective cervical nerve root blockade: experience with a safe and reliable technique using an anterolateral approach for needle placement

BACKGROUND AND PURPOSE

[corrected] Our aim was to evaluate the safety and clinical utility of a fluoroscopically guided anterolateral oblique approach technique for outpatient diagnostic and therapeutic selective cervical nerve root blockade (SCNRB).

MATERIALS AND METHODS

During a 13-year period (1994 through February 2007), 4612 patients underwent fluoroscopically guided diagnostic and/or therapeutic extraforaminal SCNRB by using an anterior oblique approach at affiliated outpatient imaging centers. Each procedure was performed by 1 of 6 procedural radiologists, all highly experienced in and actively performing spinal injections on a full-time basis in clinical practice. All of the proceduralists were thoroughly experienced with lumbar injections before endeavoring to perform SCNRBs. Nonionic contrast was injected in nearly all patients (except isolated patients with contrast allergy), and a minimum of 2 projection filming procedures were performed to document the accuracy of needle placement and contrast dispersal before the injection of therapeutic substances. All clinically significant complications beyond skin discoloration and temporary exacerbation of symptoms were recorded.

RESULTS

There were no serious neurologic complications, such as stroke, spinal cord insult, or permanent nerve root deficit. One life-threatening anaphylactic reaction occurred and was attributed to the injected materials and not the specific procedure itself. Another patient had a 3- to 4-minute grand mal seizure, from which he fully recovered within 30 minutes. There were no infections.

CONCLUSION

The technique we describe for fluoroscopically guided SCNRB is a useful and safe outpatient procedure when performed by skilled and experienced proceduralists.

Diskography: infectious complications from a series of 12,634 cases

BACKGROUND AND PURPOSE

Diskography is commonly performed to investigate pain of suspected diskogenic origin. Although uncommon, diskitis is a feared complication of this procedure. We reviewed the incidence of diskitis and other infectious complications following diskography in a large busy outpatient practice and discuss technical aspects that may contribute to infection prevention.

METHODS

We reviewed the electronic records of all diskograms obtained at our institution during a 12.25-year period, looking for all cases of procedure-related infection. All diskograms had been obtained by skilled and experienced procedural radiologists in dedicated spine-injection suites with specialized technical staff.

RESULTS

There were 12,634 examinations performed on 10,663 patients for a total of 37,135 disk levels. Of the disk levels, 5981 were cervical; 3083, thoracic; and 28,071, lumbar. Two cases of confirmed lumbar diskitis and no cases of either cervical or thoracic diskitis were seen in our series. No other infectious complications were found. The incidence of diskitis was 0.016% per examination and 0.0054% per disk level.

CONCLUSION

In skilled and experienced hands using proper technique, diskography is a safe outpatient procedure with an extremely low incidence of diskitis and other procedure-related infections.

Ergonomics and quality management--humans in interaction with technology, work environment, and organization

In many studies, ergonomics has been shown to influence human performance. The aim of this paper was to demonstrate important ergonomics influences on quality in industrial production, from the perspective of interactions between humans, technology, organization, and work environment. A second aim was to elaborate on the implications of these findings for the development of quality management strategies. This paper shows that ergonomics problems in terms of adverse work environmental conditions, inappropriate design of technology, and an unsuitable organization are important causes of quality deficiencies. Problem solving aimed at improving ergonomics, quality, and productivity simultaneously is likely to obtain support from most of the interest parties of the company, and may also enhance participation. Ergonomics has the potential of becoming a driving force for the development of new quality management strategies.

Diagnostic radiology of the cranial base

The skull base is a complex interface for bone, nerves, vessels, and musculature. With knowledge of the underlying anatomy, with an understanding of the strengths of CT and MR imaging, and with a familiarity of the commonest lesions, a rational approach to diagnostic imaging can be made, narrowing the clinical differential diagnosis and simplifying presurgical planning.

Relationships between ergonomics and quality in assembly work

Several studies indicate a relationship between ergonomic work conditions and the quality of the work. The purpose of this study was to evaluate relationships between a number of ergonomic conditions and product quality in car assembly. The most physically demanding tasks, the tasks with the most difficult parts to assemble, and the most psychologically demanding tasks, were identified by interviews with experienced assembly workers. Information on quality deficiencies was obtained from the internal quality statistics of the company and from interviews with quality control personnel. The results showed that the quality deficiencies were three times as common for the work tasks with ergonomics problems, compared with the other tasks. An increased risk of quality deficiencies was seen for all three categories of ergonomics problems investigated. Direct causes of quality deficiencies were identified, such as discomfort from strained parts of the body, organizational factors and time pressure. The analyses pointed to certain types of task that were more likely than others to cause quality problems. The results also showed that an important factor for job satisfaction was the possibility for the workers to perform their tasks with high quality. The study therefore confirms close relationships between ergonomics and quality, and thereby points to the possibility of conducting integrated change programmes aimed at improving work quality and work conditions simultaneously.

Assessment of workload from measurements of stature

The height of the body in the erect position varies by about 1% during the course of the day. It decreases rapidly after getting up and, depending on the pattern of work and rest, continues to reduce during the day; then overnight, it recovers. These changes result from changes in the height of the intervertebral discs. With conventional methods of measuring stature, these changes would go unrecognised. Apparatus has therefore been developed, allowing measurement to an accuracy of at least 1 mm. Studies have been made of static loading, dynamic lifting, running, in different types of seating and in resting postures. In general, height losses are proportional to the magnitude of lumbosacral compression, to the perception of exertion during physical exercise and to the levels of postural discomfort. Gains in height in positions of rest are proportional to the ratings for relaxation and comfort. For the ergonomist, therefore, the method offers a reliable means of assessing the effects on the spine of both physical work and rest-pauses.

Evaluation of spinal loads and chair design in seated work tasks

In this research, several methods were employed simultaneously in the evaluation of chair design and seated work tasks. These methods were grouped under four headings, namely biomechanical load, posture, discomfort and body height shrinkage. The methods were used in both field and laboratory studies. The tasks investigated included forward force development, assembly work with restricted knee-room, vision to one side, grinding, punch press work and fork lift truck driving. Two or more chair designs were compared for each task. The results from the methods were in agreement with one another. It was shown that more flexed spinal postures caused increased biomechanical load on the spine, increased discomfort and increased body height shrinkage. The methods were found to have limitations in different situations.

How does a backrest work?

After discussing the distribution of forces in the stable upright posture and illustrating the importance of the lumbar lordosis for minimising muscular effort in this position, the loadings on the spine and muscles of the back are outlined during upright sitting. It is shown that the backrest locates the lumbar spine so that the CG of the superincumbent body parts can be positioned above the vertebrae, permitting the gravity load to be transmitted to the seat without the counteracting torques which muscles would have to provide if this position was not adopted. The forces arising from other sitting positions are then discussed, and some conclusions drawn for seat design.

Shrinkage as a measure of the effect of load on the spine

A new method for measuring spinal load is proposed, whereby changes in body height are used as a measure of disc compression. The rate and magnitude of disc compression are caused by the loading and its temporal pattern. A device is reported for measuring body height (SD less than 1 mm). Experiments showed the dinural shrinkage during a working day and the rapid recovery when lying down. Other experiments demonstrated how the rate of shrinkage is a function of the load on the spine. Further, shrinkage when sitting in different chairs has been compared, and the results are in agreement with disc pressure measurements, reported in the literature. Finally, examples are given of how the method can be used in ergonomic evaluations.