A comparative study of the anatomical, radiological and therapeutic features of the lumbar facet joints

Therapeutic Facet Joint Interventions in the Lumbar Spine: An Economic Value Perspective

OBJECTIVE

In this narrative review, the current literature on therapeutic interventions for low back pain of facet joint etiology is assessed from an economic value perspective.

SUMMARY OF BACKGROUND DATA

The efficacy and economics of facet joint interventions in the treatment of lumbar back pain is a controversial topic. Trends show that facet joint interventions are becoming increasingly used, perhaps as physicians become more averse to treating chronic low back pain with opioids. With the emphasis on value-based spine care and changing reimbursement models, the perspective of rigorously evaluating the outcomes these interventions provide and the costs they incur is particularly relevant.

DISCUSSION

Although the evidence is noted to be limited, most systematic reviews fail to demonstrate the therapeutic utility of intra-articular facet joint injections in low back pain because of high study heterogeneity. A few good quality studies and systematic reviews describe moderate evidence for the utilization of therapeutic medial branch blocks and radiofrequency neurotomies in alleviating facet joint pain.

CONCLUSION

Consequently, there is a need for high-quality cost-effectiveness studies for facet joint interventions so that evidence-based and economically viable solutions can be used to optimize patient care at a societally affordable price.

Acquired Degenerative Changes of the Intervertebral Segments at and Supradjacent to the Lumbosacral Junction

In earlier evolutionary times, mammals were primarily quadrupeds, although other bipeds have been represented during the course of the Earth's several billion-year history. In many cases, either the bipedal stance yielded a large tail and hypoplastic upper extremities (e.g., Tyrannosaurus rex, the kangaroo), or it culminated in hypoplasia of the tail and further development and specialization of the upper extremities (e.g., nonhuman primates and human beings). In the human species this relatively recently acquired posture resulted in a more or less pronounced lumbosacral lordosis. In turn, certain compensatory anatomic features have since occurred. These include the normal characteristic posteriorly directed wedge-shape of the L5 vertebral body and the L5-S1 intervertebral disc; the L4 vertebral body and the L4-L5 and L3-4 disc may be similarly visibly affected.

These compensatory mechanisms, however, have proved to be functionally inadequate over the present long-term of the human life span. Upright posture leads to increased weight bearing in humans that progressively causes excess stresses at and suprajacent to the lumbosacral junction. These combined factors result in accelerated aging and degenerative changes and a predisposition to frank biomechanical failure of the subcomponents of the spinal column in these spinal segments.

One other specific problem that occurs at the lumbosacral junction that predisposes toward premature degeneration is the singular relationship that exists between a normally mobile segment of spine (i.e., the lumbar spine), and a normally immobile one (i.e., the sacrum). It is well known that mobile spinal segments adjacent to congenitally or acquired fused segments have a predilection toward accelerated degenerative changes. The only segment of the spine in which this is invariably normally true is at the lumbosacral junction (i.e., the unfused lumbar spine adjoining the fused sacrum).

Nevertheless, biomechanical failures of the human spine are not lethal traits; in most cases today, mankind reaches sexual maturity before spinal biomechanical failure precludes sexual reproduction. For this gene-preserving reason, degenerative spinal disorders will likely be a part of modern societies for the foreseeable eternity of the race.

The detailed alterations accruing from the interrelated consequences of and phenomena contributing to acquired degenerative changes of the lumbosacral intervertebral segments as detailed in this discussion highlight the extraordinary problems that are associated with degenerative disease in this region of the spine. Further clinicoradiologic research in this area will progressively determine the clinical applications and clinical efficacy of the various traditional and newer methods of therapy in patients presenting with symptomatic acquired collapse of the intervertebral discs at and suprajacent to the lumbosacral junction and the interrelated degenerative alterations of the nondiscal structures of the spine.

Grading Osteoarthritic Changes of the Zygapophyseal Joints from Radiographs: A Reliability Study

OBJECTIVE

This study tested the reliability of a 5-point ordinal scale used to grade the severity of degenerative changes of zygapophyseal (Z) joints on standard radiographs.

METHODS

Modifications were made to a Kellgren grading system to improve agreement for grading the severity of osteoarthritic changes in lumbar Z joints. These included adding 1 grade of no degeneration, multiple radiographic views, and structured examiner training. Thirty packets of radiographic files were obtained, which included representation of all 5 grades including no degeneration (0) and Kellgren's 4-point (1-4) joint degeneration classification criteria. Radiographs were digitized to create a radiographic atlas that was given to examiners for individual study and blinded evaluation sessions. Intrarater and interrater agreement was determined by weighted κ (κw) from the examination of 79 Z joints (25 packets).

RESULTS

Using the modified scale and after training, examiners demonstrated a moderate-to-substantial level of interrater agreement (κw = 0.57, 0.60, and 0.68). Intrarater agreement was moderate (κw = 0.42 and 0.54).

CONCLUSIONS

The modified Kellgren 5-point grading system provides acceptable intrarater and interrater reliability when examiners are adequately trained. This grading system may be a useful method for future investigations assessing radiographic osteoarthritis of the Z joints.

Trends in performance indicators of neuroimaging anatomy research publications: a bibliometric study of major neuroradiology journal output over four decades based on web of science database

Quantitative, qualitative, and innovative application of bibliometric research performance indicators to anatomy and radiology research and education can enhance cross-fertilization between the two disciplines. We aim to use these indicators to identify long-term trends in dissemination of publications in neuroimaging anatomy (including both productivity and citation rates), which has subjectively waned in prestige during recent years. We examined publications over the last 40 years in two neuroradiological journals, AJNR and Neuroradiology, and selected and categorized all neuroimaging anatomy research articles according to theme and type. We studied trends in their citation activity over time, and mathematically analyzed these trends for 1977, 1987, and 1997 publications. We created a novel metric, "citation half-life at 10 years postpublication" (CHL-10), and used this to examine trends in the skew of citation numbers for anatomy articles each year. We identified 367 anatomy articles amongst a total of 18,110 in these journals: 74.2% were original articles, with study of normal anatomy being the commonest theme (46.7%). We recorded a mean of 18.03 citations for each anatomy article, 35% higher than for general neuroradiology articles. Graphs summarizing the rise (upslope) in citation rates after publication revealed similar trends spanning two decades. CHL-10 trends demonstrated that more recently published anatomy articles were likely to take longer to reach peak citation rate. Bibliometric analysis suggests that anatomical research in neuroradiology is not languishing. This novel analytical approach can be applied to other aspects of neuroimaging research, and within other subspecialties in radiology and anatomy, and also to foster anatomical education.

Indicators of lumbar zygapophyseal joint pain: survey of an expert panel with the Delphi technique

BACKGROUND AND PURPOSE

The lumbar zygapophyseal joints (LZJs) are thought to be a source of low back pain (LBP); however, no valid or reliable indicators exist. The purpose of this study was to obtain a consensus from an expert panel on the indicators of LZJ pain.

SUBJECTS

A multidisciplinary panel of 20 experts in the field of LBP participated in this study.

METHODS

A 3-round Delphi survey designed to obtain a consensus on the indicators of LZJ pain was completed by use of accepted protocols. Subjects also were asked to justify their selection of each indicator.

RESULTS

Following the 3 rounds, consensus was achieved, and 12 indicators were identified. Those that reached the highest levels of consensus were a positive response to facet joint injection, localized unilateral LBP, positive medial branch block, pain upon unilateral palpation of the LZJ or transverse process, lack of radicular features, pain eased by flexion, and pain, if referred, located above the knee. Justifications for the experts' selection of the indicators, predominantly based on pathoanatomical mechanisms, also were described.

DISCUSSION AND CONCLUSION

This Delphi survey identified 12 indicators of LZJ pain, each with an associated pathoanatomical mechanism justifying selection. This survey provides preliminary validation for these indicators, which will be of value in further research into the classification and treatment of LZJ pain.

Acquired degenerative changes of the intervertebral segments at and suprajacent to the lumbosacral junction

A review of the imaging features of normal and degenerative anatomy of the spine on medical imaging studies shows features that have been largely overlooked or poorly understood by the imaging community in recent years. The imaging methods reviewed included computed tomography (CT) with multiplanar reconstructions and magnetic resonance imaging (MRI). A routine part of the MRI examination included fat-suppressed T2 weighted fast-spin- or turbo-spin-echo acquisitions. As compared to the normal features in asymptomatic volunteers, alterations in the observed CT/MRI morphology and MR signal characteristics were sought in symptomatic individuals. Findings in symptomatic subjects which departed from the normal anatomic features of the posterior spinal elements in asymptomatic volunteers included: rupture of the interspinous ligament(s), neoarthrosis of the interspinous space with perispinous cyst formation, posterior spinal facet (zygapophyseal joint) arthrosis, related central spinal canal, lateral recess (subarticular zone) and neural foramen stenosis, posterior element alterations associated with various forms of spondylolisthesis, and perispinal muscle rupture/degeneration. These findings indicate that the posterior elements are major locations of degenerative spinal and perispinal disease that may accompany or even precede degenerative disc disease. Although not as yet proven as a reliable source of patient signs and symptoms in all individuals, because these observations may be seen in patients with radicular, referred and/or local low back pain, they should be considered in the evaluation of the symptomatic patient presenting with a clinical lumbosacral syndrome. Imaging recommendations, in addition to the usual close scrutiny of these posterior spinal elements and perispinal soft tissues on CT and MRI, include the acquisition of high-resolution multiplanar CT reconstructions, and fat-suppressed T2 weighted fast-spin- or turbo-spin-echo sequence MRI in at least one plane in every examination of the lumbar spine.

Acquired degenerative changes of the intervertebral segments at and suprajacent to the lumbosacral junction. A radioanatomic analysis of the nondiskal structures of the spinal column and perispinal soft tissues

In earlier evolutionary times, mammals were primarily quadrupeds. However, other bipeds have also been represented during the course of the Earth's several billion year history. In many cases, either the bipedal stance yielded a large tail and hypoplastic upper extremities (e.g., Tyrannosaurus rex and the kangaroo), or it culminated in hypoplasia of the tail and further development and specialization of the upper extremities (e.g., nonhuman primates and human beings). In the human species this relatively recently acquired posture resulted in a more or less pronounced lumbosacral kyphosis. In turn, certain compensatory anatomic features have since occurred. These include the normal characteristic posteriorly directed wedge-shape of the L5 vertebral body and the L5-S1 intervertebral disk; the L4 vertebral body and the L4-L5 disk may be similarly visibly affected. These compensatory mechanisms, however, have proved to be functionally inadequate over the long term of the human life span. Upright posture also leads to increased weight bearing in humans that progressively causes excess stresses at and suprajacent to the lumbosacral junction. These combined factors result in accelerated aging and degenerative changes and a predisposition to frank biomechanical failure of the subcomponents of the spinal column in these spinal segments. One other specific problem that occurs at the lumbosacral junction that predisposes toward premature degeneration is the singular relationship that exists between a normally mobile segment of spine (i.e., the lumbar spine) and a normally immobile one (i.e., the sacrum). It is well known that mobile spinal segments adjacent to congenitally or acquired fused segments have a predilection toward accelerated degenerative changes. The only segment of the spine in which this is invariably normally true is at the lumbosacral junction (i.e., the unfused lumbar spine adjoining the fused sacrum). Nevertheless, biomechanical failures of the human spine are not lethal traits; in most cases today, mankind reaches sexual maturity before spinal biomechanical failure precludes sexual reproduction. For this gene-preserving reason, degenerative spinal disorders will likely be a part of modern societies for the foreseeable eternity of the race. The detailed alterations accruing from the interrelated consequences of and phenomena contributing to acquired degenerative changes of the lumbosacral intervertebral segments as detailed in this discussion highlight the extraordinary problems that are associated with degenerative disease in this region of the spine. Further clinicoradiologic research in this area will progressively determine the clinical applications and clinical efficacy of the various traditional and newer methods of therapy in patients presenting with symptomatic acquired collapse of the intervertebral disks at and suprajacent to the lumbosacral junction and the interrelated degenerative alterations of the nondiskal structures of the spine.

Therapeutic infiltration of the facet joint in minor intervertebral disease

SUMMARY

A CT-guided infiltration technique of the facet joints was employed on a group of 20 patients suffering from sciatica without any signs ofmorphostructural alteration of the facet joints, secondary to Minor Intervertebral Disease (MID). The typical flouroscopically guided intra-articular facet arthrography has been substituted by a CT-guided technique that privileges therapy rather than diagnosis. The study involved 20 patients between 29 and 57 years of age (average 44.5), of both sexes (16 females and four males). The average time which elapsed from onset of symptomatology was 9.5 months. At seven days after the first treatment subjective results were considered excellent by 11 patients (55%), good by one (5%) and satisfactory by one (5%). Six out of20 patients (30%) failed to gain any relief of symptoms. Only one patient (5%) had a worsening of pain. Clinical evaluation by the physician at the same time showed a good result in 11 patients (55%), satisfactory in two (10%). In six patients (30%) the symptomatology was unchanged. At 4 months the subjective results were excellent in three (15%), good in six (30%) and satisfactory in two (10%) . Nine (45%) had no positive results. The clinical examination was excellent in tWo (10%), good in seven (35%), satisfactory in two (10%) and without any relief of symptomatology in nine (45%). These results encourage the use of CT-guided infiltration that, together with the small amount of contrast medium injected into the joint space, make it a safe technique for patients, avoiding or reducing complications.

The prevalence of lumbar paraspinal spontaneous activity in asymptomatic subjects

Electrodiagnostic findings of fibrillations and positive sharp waves in the lumbosacral paraspinals in patients without previous back surgery has been generally considered to be abnormal, consistent with posterior rami denervation. In some cases, it is the only abnormality on the electromyographic examination. This study was undertaken to determine the prevalence of abnormal spontaneous activity in lumbosacral paraspinals in asymptomatic individuals. Nine (14.5%) of 62 subjects studied had positive sharp waves or fibrillations noted on the needle examination of bilateral lumbosacral paraspinal muscles. There was a significant increase in the prevalence of abnormal activity with increasing age. This suggests that caution should be taken in attributing radiculopathy as the etiology of low back pain when electromyographic lumbosacral paraspinal abnormalities are the only positive findings in the middle-aged or older individual.

Clinical efficacy of imaging modalities in the diagnosis of low-back pain disorders

This review provides methodological background and some guidelines for the evaluation of imaging modalities for the lumbar spine and reviews the current literature on the basis of different levels of efficacy which consider standards beyond technical quality or diagnostic accuracy. From a MEDLINE search, 672 articles (1985-1995) were retrieved which focused on the development or application of imaging modalities for lumbar spinal disorders. The papers were categorized according to different efficacy levels at which the imaging modalities were assessed. This review has demonstrated that the vast majority of reports evaluate imaging studies for the lumbar spine only at the technical efficacy level. A minor proportion of the articles focus on the evaluation at the level of diagnostic accuracy. Articles which assess imaging studies on a higher level of efficacy (e.g., diagnostic and therapeutic impact, patient outcome and cost-benefit analysis) are sparse. This review has outlined frequent methodological flaws in patient selection and design of imaging studies for the lumbar spine. The spine specialist should therefore become very critical in the interpretation of those studies and pay attention to patient selection and spectrum, choice of the reference standard, sample size, various forms of biases, and the reasoning behind clinical recommendations in order to improve his patient care.

Hypertrophic synovitis and osteoarthritis of the cervical facet joint. Report of two cases

We report two cases of cervical facet joint osteoarthritis associated with radiculopathy. Contrast-enhanced computed tomography showed a halo of enhancing soft tissue surrounding the facet joints and narrowing the neural foramen. Hypertrophic synovial masses were discovered and removed at the time of operation in each case, resulting in relief of the radicular symptoms.