The value of dynamic radiographic myelography in addition to magnetic resonance imaging in detection lumbar spinal canal stenosis: A prospective study

The efficacy of 3D gait analysis to evaluate surgical (and rehabilitation) outcome after degenerative lumbar surgery

BACKGROUND

Lumbar degenerative conditions are a major cause of back pain and disability in individuals aged 45 and above. Gait analysis utilizes sensor technology to collect movement data, aiding in the evaluation of various gait aspects like spatiotemporal parameters, joint angles, neuromuscular activity, and joint forces. It is widely used in conditions such as cerebral palsy and knee osteoarthritis. This research aims to assess the effectiveness of 3D gait analysis in evaluating surgical outcomes and postoperative rehabilitation for lumbar degenerative disorders.

METHODS

A prospective self-controlled before-after study (n = 85) carried out at our Hospital (Sep 2018 - Dec 2021) utilized a 3D motion analysis system to analyze gait in patients with lumbar degenerative diseases. The study focused on the multifidus muscle, a crucial spinal muscle, during a minimally invasive lumbar interbody fusion surgery conducted by Shandong Weigao Pharmaceutical Co., Ltd. Pre- and postoperative assessments included time-distance parameters (gait speed, stride frequency, stride length, stance phase), hip flexion angle, and stride angle. Changes in 3D gait parameters post-surgery and during rehabilitation were examined. Pearson correlation coefficient was employed to assess relationships with the visual analog pain scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopedic Association (JOA) scores. Patient sagittal alignment was evaluated using "Surgimap" software from two types of lateral radiographs to obtain parameters like pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), intervertebral space height (DH), posterior height of the intervertebral space (PDH) at the operative segment, and anterior height of the intervertebral space (ADH).

RESULTS

By the 6th week post-operation, significant improvements were observed in the VAS score, JOA score, and ODI score of the patients compared to preoperative values (P < 0.05), along with notable enhancements in 3D gait quantification parameters (P < 0.05). Pearson correlation analysis revealed a significant positive correlation between improvements in 3D gait quantification parameters and VAS score, JOA score, and ODI value (all P < 0.001).

CONCLUSION

3D gait analysis is a valuable tool for evaluating the efficacy of surgery and rehabilitation training in patients.

Japanese Orthopaedic Association (JOA) clinical practice guidelines on the management of lumbar spinal stenosis, 2021 - Secondary publication

BACKGROUND

The Japanese Orthopaedic Association (JOA) guideline for the management of lumbar spinal stenosis (LSS) was first published in 2011. Since then, the medical care system for LSS has changed and many new articles regarding the epidemiology and diagnostics of LSS, conservative treatments such as new pharmacotherapy and physical therapy, and surgical treatments including minimally invasive surgery have been published. In addition, various issues need to be examined, such as verification of patient-reported outcome measures, and the economic effect of revised medical management of patients with lumbar spinal disorders. Accordingly, in 2019 the JOA clinical guidelines committee decided to update the guideline and consequently established a formulation committee. The purpose of this study was to describe the formulation we implemented for the revision of the guideline, incorporating the recent advances of evidence-based medicine.

METHODS

The JOA LSS guideline formulation committee revised the previous guideline based on the method for preparing clinical guidelines in Japan proposed by the Medical Information Network Distribution Service in 2017. Background and clinical questions were determined followed by a literature search related to each question. Appropriate articles based on keywords were selected from all the searched literature. Using prepared structured abstracts, systematic reviews and meta-analyses were performed. The strength of evidence and recommendations for each clinical question was decided by the committee members.

RESULTS

Eight background and 15 clinical questions were determined. Answers and explanations were described for the background questions. For each clinical question, the strength of evidence and the recommendation were both decided, and an explanation was provided.

CONCLUSIONS

The 2021 clinical practice guideline for the management of LSS was completed according to the latest evidence-based medicine. We expect that this guideline will be useful for all medical providers as an index in daily medical care, as well as for patients with LSS.

When does CT myelography add value beyond MRI for lumbar degenerative disease?

BACKGROUND CONTEXT

In patients with lumbar spinal stenosis, it is crucial for clinicians to identify all symptomatic levels. Prior studies have demonstrated that CT myelography has a greater sensitivity in revealing stenosis (94.4%) compared to MRI (75.9%). However, this is an invasive test that should be used judiciously. No study has identified subgroups of patients that do or do not benefit from this additional invasive testing.

PURPOSE

The objective of this study was to identify subgroups of patients with lumbar stenosis for whom CT myelogram could be expected to provide additional information following an MRI scan.

STUDY DESIGN

Retrospective chart review.

PATIENT SAMPLE

Consecutive series of patients with lumbar degenerative disease seen at a single multisurgeon tertiary spine center.

OUTCOME MEASURES

Degree of stenosis on MRI or CT myelo.

METHODS

Medical records were reviewed to collect standard demographic and surgical data and patient diagnoses. MRI and CT myelo obtained within 6 months of each other in patients >45 years old with a diagnosis of central stenosis, spondylolisthesis or degenerative scoliosis were reviewed. Each lumbar level was recorded as mild, moderate, or severe based on the radiologist's report. Fisher exact test was performed with change in recorded severity of stenosis from MRI to CT myelo as the primary outcome of interest.

RESULTS

Of 269 patients, 207 (80%) had at least one level of moderate or severe central stenosis on MRI and 62 had mild or no stenosis on MRI. Of the 207, 139 (67%) had multilevel stenosis and 68 (33%) had single level stenosis. CT myelo identified a greater proportion of additional stenotic levels in patients with multilevel stenosis (80/139, 58%) compared to patients with single-level stenosis (27/68, 40%, p=.018). In 62 patients with a clinical diagnosis of lumbar stenosis but no moderate to severe stenosis on MRI, CT myelogram identified three additional stenotic levels (3/65, 5%, p=.836).

CONCLUSIONS

CT myelography is not as useful in providing additional information in patients with no stenosis or single level stenosis as compared to patients with multilevel stenosis.

DOES DECUBITUS AFFECT NEURAL ELEMENTS POSITIONING? A MRI STUDY COMPARING DORSAL AND LATERAL POSITION

ABSTRACT Objective To evaluate the displacement of nerve structures according to the decubitus position of the patient in a magnetic resonance imaging (MRI) study. Methods MRI was performed at a radiology clinic in 20 patients in dorsal and right lateral decubitus. The measurement considered was the shortest distance between the dura mater and the medial wall of the pedicle. Results The largest measurement was 11.6 mm in left lateral decubitus, 12.2 mm in right lateral decubitus, 10.5 mm in right dorsal decubitus, and 9.2 mm in left dorsal decubitus. In some patients the space between the medial wall of the pedicle and the dura mater was larger when in lateral decubitus, while in others when in dorsal decubitus. The mean displacement of the measurements on the left was 1.14 mm and on the right 1.355 mm. Conclusions The structures moved on average little more than 1 mm in the positions studied. The positioning of the patient for surgery does not change the space to be approached, being the surgeon’s choice according to his learning curve. Level of evidence II; Prospective study of lower quality.

Do Curve Characteristics Influence Stenosis Location and Occurrence of Radicular Pain in Adult Degenerative Scoliosis?

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The aim of this study was to describe the various locations of spinal stenosis (LSS) in lumbar scoliosis and its related clinical symptoms.

INTRODUCTION

Adults with lumbar scoliosis often present with pain and disability. Association of scoliosis and stenosis is not rare, but remains sparsely explored. Consequences of scoliosis on stenosis location and treatment remain debatable.

METHODS

Patients operated for symptomatic LSS with lumbar scoliosis (Cobb angle >20°) from 2015 to 2016 were included. All patients completed preoperative clinical and neurologic examination. Coronal and sagittal radiographic parameters, rotatory subluxation (RS), and spondylolisthesis were analyzed on full spine radiographs. Computed tomographic scan multiplanar reconstructions were performed to measure central, foraminal, and lateral recess stenosis, from T10 to the sacrum.

RESULTS

A total of 76 patients were included (69 ± 9 years old, 77% female). Sixty percent had neurogenic claudication, and L5 was the most common radicular pain (41%). The mean Cobb angle was 33° ± 16°. Overall, 35 (46%) patients had coronal malalignment; in 69%, side of the coronal tilt corresponded to side of the concavity of the lumbosacral curve. Sixty patients had RS (most frequent level L3-L4). In 50% of the cohort, RS was located at the junction between the lumbar and lumbosacral curves. In 70% (n = 53) of the patients, central stenosis occurred at the junction between the lumbar and lumbosacral curves. Foraminal and lateral stenosis were most frequently observed in the concavity of the distal lumbosacral curve. L5 radicular pain was significantly more frequent in case of lumbosacral contra-curve and right coronal malalignment.

CONCLUSION

LSS is frequent in lumbar scoliosis. Relationships exist between curve characteristics and symptomatic LSS in lumbar scoliosis; especially, concavity of the lumbosacral contra-curve and the junctional level between the lumbar curve and the lumbosacral contra-curve. Therefore, accurate analysis of stenosis in ASD seems mandatory, to at least perform decompression because perfect planned treatment for stenosis and scoliosis correction might not always be possible because of the patient's general health status.

LEVEL OF EVIDENCE

Level 4.

Updated imaging does not affect revision rates in adults undergoing spine surgery for lumbar degenerative disease

OBJECTIVEDiagnostic workup for lumbar degenerative disc disease (DDD) includes imaging such as radiography, MRI, and/or CT myelography. If a patient has unsuccessful nonoperative treatment, the surgeon must then decide if obtaining updated images prior to surgery is warranted. The purpose of this study was to investigate whether the timing of preoperative neuroimaging altered clinical outcome, as reflected by the subsequent rate of revision surgery, in patients with degenerative lumbar spinal pathology.METHODSFrom the Health Care Service Corporation administrative claims database, adult patients (minimum age 55 years old) with lumbar DDD who underwent surgery including posterior lumbar decompression with and without fusion (1-2 levels) and at least 5 years of continuous coverage after the index surgery were identified. The chi-square test was used to determine differences in revision rates stratified by timing of each imaging procedure relative to the index procedure (< 6 months, 6-12 months, 12-24 months, or > 24 months).RESULTSOf 28,676 cases identified, 5128 (18%) had revision surgery within 5 years. The timing of preoperative MRI or plain radiography was not associated with revision surgery. Among the entire cohort, there was a lower incidence of revision surgery in patients who had a CT myelogram within 1 year prior to the index surgery (p = 0.017). This observation was strongest in patients undergoing decompression only (p = 0.002), but not significant in patients undergoing fusion (p = 0.845).CONCLUSIONSRoutine reimaging prior to surgery, simply because the existing MRI is 6-12 months old, may not be beneficial, at least as reflected in subsequent revision rates. The study also suggests that there may be a subset of patients for whom preoperative CT myelography reduces revision rates. This topic has important financial implications and deserves further study in a more granular data set.

Myelography in the Assessment of Degenerative Lumbar Scoliosis and Its Influence on Surgical Management

Objective

Myelography has been shown to highlight foraminal and lateral recess stenosis more readily than computed tomography (CT) or magnetic resonance imaging (MRI). It also has the advantage of providing dynamic assessment of stenosis in the loaded spine. The advent of weight-bearing MRI may go some way towards improving assessment of the loaded spine and is less invasive, however availability remains limited. This study evaluates the potential role of myelography and its impact upon surgical decision making.

Methods

Of 270 patients undergoing myelography during 2006–2009, a period representing peak utilisation of this imaging modality in our unit, we identified 21 patients with degenerative scoliosis who fulfilled our inclusion criteria. An operative plan was formulated by our senior author based initially on interpretation of an MRI scan. Subsequent myelogram and CT myelogram investigations were scrutinised, with any additional abnormalities noted and whether these impacted upon the operative plan.

Results

From our 21 patients, 18 (85.7%) had myelographic findings not identified on MRI. Of note, in 4 patients, supine CT myelography yielded additional information when compared to supine MRI in the same patients. The management of 7 patients (33%) changed as a result of myelographic investigation. There were no complications of myelography of the total 270 analysed.

Conclusion

MRI scan alone understates the degree of central and lateral recess stenosis. In addition to the additional stenosis displayed by dynamic myelography in the loaded spine, we have also shown that static myelography and CT myelography are also invaluable tools with regards to surgical planning in these patients.