Value of Bone Scintigraphy and Single Photon Emission Computed Tomography (SPECT) in Lumbar Facet Disease and Prediction of Short-term Outcome of Ultrasound Guided Medial Branch Block with Bone SPECT

Reporting of Facet Joint Inflammation in Lumbar Spine MRI Studies in Patients With Low Back Pain

STUDY DESIGN

Retrospective.

OBJECTIVE

We aimed to assess the frequency of facet joint inflammatory features noted in routine radiology reports of lumbar spine magnetic resonance imaging (MRI) studies among patients with chronic low back pain.

SUMMARY OF BACKGROUND DATA

Facet joint arthropathy is one of the most common causes of chronic low back pain. It may encompass various inflammatory imaging characteristics, such as facet joint effusion, bone marrow edema, and soft tissue edema. The extent to which radiology reports mention inflammatory features of the lumbar facet joints and the accuracy of these reports have not been investigated.

MATERIALS AND METHODS

The authors performed a chart review on 49 subjects with previous facet-related interventions ( i.e . medial branch blocks or intra-articular facet joint injection) and MRI available in the medical record. One senior musculoskeletal radiologist and a musculoskeletal radiology fellow graded the inflammatory features using a published facet joint inflammation grading system [Gold Standard (GS)]. The authors identified the inflammatory markers mentioned in the radiology reports and calculated the sensitivity and positive predictive value of the radiology reports compared with GS readings.

RESULTS

Compared with the GS, the sensitivity of radiology reports for facet joint effusion, bone marrow, and soft tissue edema ranged from 6% to 22%, and the positive predictive value ranged from 25% to 100%. L4/5 had the highest number of cases with inflammatory features noted on the reports.

CONCLUSION

Inflammatory findings, such as facet joint effusion, bone marrow edema, and soft tissue edema, are not commonly identified in radiology reports. Further investigations are needed to determine the clinical importance of MRI-detected lumbar facet joint inflammatory features as a potential mechanism of nociception and as a predictor of outcomes following injections or other therapies.

SPECT/CT Scan: A New Diagnostic Tool in Pain Medicine

PURPOSE OF REVIEW

The purpose of this review is to evaluate the role of SPECT/CT in identifying facet joint arthropathy and the outcomes of interventions with SPECT/CT as an adjunct.

RECENT FINDINGS

A positive finding of facet arthropathy on SPECT/CT is associated with a higher likelihood of a unilateral procedure and a significantly more effective intervention compared with those performed on patients with facet arthropathy diagnosed only by clinical and/or radiologic examination. Surgical treatment of SPECT/CT-positive findings appears to have a good effect; however, due to limitations in the available studies, no strong conclusion can be drawn. SPECT/CT has a good correlation identifying pain generators in chronic neck and back pain. SPECT/CT-targeted facet interventions demonstrate a higher success rate, but SPECT/CT is not recommended as a first-line diagnostic tool prior to diagnostic facet interventions. More robust studies are needed to confirm the higher success of surgical treatment for SPECT/CT-positive facet arthropathy.

Predictors of Outcomes After Lumbar Intra-Articular Facet Joint Injections and Medial Branch Blocks: A Scoping Review

STUDY DESIGN

A scoping review.

OBJECTIVE

We aimed to identify and describe the factors associated with the patient-reported response after lumbar intra-articular facet joint (FJ) injections or medial branch blocks (MBBs).

SUMMARY OF BACKGROUND DATA

FJ osteoarthritis is among the most common causes of chronic low back pain. Management often includes FJ intra-articular injection and MBBs (which may be followed by radiofrequency ablation of the nerves innervating these joints). However, the success of these approaches is variable, prompting interest in identifying patient characteristics (imaging features, clinical signs, and among others) associated with response to these types of facet injections.

MATERIALS AND METHODS

We performed a literature search on factors associated with patient-reported outcomes after lumbar FJ intra-articular injections or MBBs for patients with low back pain published in English or Spanish between 2000 and 2023. We excluded duplicate papers that did not describe factors associated with outcomes or those describing other interventions. We collected data on the association of these factors with patient-reported outcomes.

RESULTS

Thirty-seven studies met the inclusion criteria and were analyzed. These studies evaluated factors, such as age, depression, and single photon emission computed tomography (SPECT), and among variables. Age and imaging findings of facet arthropathy were the most frequently described factors. Imaging findings of FJ arthropathy and positive SPECT were often associated with positive results after intra-articular FJ injections or MBBs. In contrast, younger age and smoking were frequently associated with less favorable clinical outcomes.

CONCLUSION

Numerous factors were considered in the 37 studies included in this review. Imaging findings of facet arthropathy, duration of pain, and positive SPECT were consistently associated with favorable results after facet interventions.

Unexpected Solitary Subcutaneous Metastasis From Esophageal Carcinoma Revealed by MDP Bone Scintigraphy

ABSTRACT

A 60-year-old man with back pain underwent 99mTc-MDP to evaluate bone metastases from newly esophageal carcinoma. No bone metastasis was found on the whole-body bone scan. Unexpectedly, subcutaneous metastasis revealed increased 99mTc-MDP activity.

Low back pain of disc, sacroiliac joint, or facet joint origin: a diagnostic accuracy systematic review

Background

The accuracy of diagnostic tests available in primary care to identify the disc, sacroiliac joint, and facet joint as the source of low back pain is uncertain.

Methods

Systematic review of diagnostic tests available in primary care. MEDLINE, CINAHL, and EMBASE were searched between March 2006 and 25th January 2023. Pairs of reviewers independently screened all studies, extracted data, and assessed risk of bias using QUADAS-2. Pooling was performed for homogenous studies. Positive likelihood ratios (+LR) ≥2 and negative likelihood ratios (-LR) ≤0.5 were considered informative. This review is registered with PROSPERO (CRD42020169828).

Findings

We included 62 studies: 35 investigated the disc, 14 the facet joint, 11 the sacroiliac joint, and 2 investigated all three structures in patients with persistent low back pain. For risk of bias, the domain 'reference standard' scored worst, however approximately half the studies were of low risk of bias for every other domain. For the disc, pooling demonstrated MRI findings of disc degeneration and annular fissure resulted in informative +LRs: 2.53 (95% CI: 1.57-4.07) and 2.88 (95% CI: 2.02-4.10) and -LRs: 0.15 (95% CI: 0.09-0.24) and 0.24 (95% CI: 0.10-0.55) respectively. Pooled results for Modic type 1, Modic type 2, and HIZ on MRI, and centralisation phenomenon yielded informative +LRs: 10.00 (95% CI: 4.20-23.82), 8.03 (95% CI: 3.23-19.97), 3.10 (95% CI: 2.27-4.25), and 3.06 (95% CI: 1.44-6.50) respectively, but uninformative -LRs: 0.84 (95% CI: 0.74-0.96), 0.88 (95% CI: 0.80-0.96), 0.61 (95% CI: 0.48-0.77), and 0.66 (95% CI: 0.52-0.84) respectively. For the facet joint, pooling demonstrated facet joint uptake on SPECT resulted in informative +LRs: 2.80 (95% CI: 1.82-4.31) and -LRs: 0.44 (95% CI: 0.25-0.77). For the sacroiliac joint, a combination of pain provocation tests and absence of midline low back pain resulted in informative +LRs of 2.41 (95% CI: 1.89-3.07) and 2.44 (95% CI: 1.50-3.98) and -LRs of 0.35 (95% CI: 0.12-1.01) and 0.31 (95% CI: 0.21-0.47) respectively. Radionuclide imaging yielded an informative +LR 7.33 (95% CI: 1.42-37.80) but an uninformative -LR 0.74 (95% CI: 0.41-1.34).

Interpretation

There are informative diagnostic tests for the disc, sacroiliac joint, and facet joint (only one test). The evidence suggests a diagnosis may be possible for some patients with low back pain, potentially guiding targeted and specific treatment approaches.

Funding

There was no funding for this study.

Role of Single-Photon Emission Computed Tomography Imaging in the Diagnosis and Treatment of Chronic Neck or Back Pain Caused by Spinal Degeneration: A Systematic Review

BACKGROUND

Chronic neck or back pain is a common clinical problem. The most likely cause is degenerative change, whereas other causes are relatively rare. There is increasing evidence on using hybrid single-photon emission computed tomography (SPECT) to identify the pain generator in spine degeneration. This systematic review explores the diagnostic and therapeutic evidence on chronic neck or back pain examined by SPECT.

METHODS

This review is reported in accordance with the PRISMA guidelines. In October 2022, we searched the following sources: MEDLINE, Embase, CINAHL, SCOPUS, and 3 other sources. Titles and abstracts were screened and classified into diagnostic studies, facet block studies, and surgical studies. We synthesized the results narratively.

RESULTS

The search yielded 2347 records. We identified 10 diagnostic studies comparing SPECT or SPECT/computed tomography (CT) with magnetic resonance imaging, CT, scintigraphy, or clinical examination. Furthermore, we found 8 studies comparing the effect of facet block intervention in SPECT-positive and SPECT-negative patients with cervicogenic headache, neck pain, and lower back pain. Five surgical studies describing the effect of fusion for facet arthropathy in the craniocervical junction, subaxial cervical spine, or the lumbar spine were identified.

CONCLUSIONS

According to the available literature, a positive finding on SPECT in facet arthropathy is associated with a significantly higher facet blockade effect. Surgical treatment of positive findings has a good effect, but this has not been confirmed by controlled studies. SPECT/CT might therefore be a useful method in the evaluation of patients with neck or back pain, especially in cases of unclear findings or multiple degenerative changes.

The positive prediction of single photon emission computed tomography/ computed tomography (SPECT/CT) in the outcome of intervention for cervical facet pain

BACKGROUND CONTEXT

Previous studies have reported that magnetic resonance imaging (MRI) and computed tomography (CT) do not predict response to facet blocks. However, single photon emission computed tomography (SPECT) uptake within facet joints has been shown to correlate with pain relief after intervention in the lumbar spine. There is minimal data regarding the predictive value of single photon emission computed tomography/computed tomography (SPECT/CT) for neck pain.

PURPOSE

The aim of this study was to evaluate the utility of SPECT/CT in patients with axial neck pain for the identification of specific facet joints that would benefit from diagnostic and therapeutic facet joint steroid injections and/or medial branch block/RFA treatments.

STUDY DESIGN

A retrospective cohort study.

PATIENT SAMPLE

One hundred seventy-nine patients at a single institution pain center with neck pain and a SPECT/CT scan between 2009 and 2015. One hundred twelve patients had no prior intervention at the level of interest and met inclusion criteria.

OUTCOME MEASURES

Pain reduction at 50% and 80% thresholds within 24 hours of facet intervention. Concordance of facet intervention with the focus of maximal uptake on SPECT/CT scan.

METHODS

All patients were referred to our institution's Center for Pain Medicine and were treated with facet interventions. The site of facet intervention was determined by pain center providers based on their clinical examination and interpretation of images. Groups were formed based on whether the facet intervention included the level of maximal uptake on SPECT/CT scan. A positive response to intervention was defined at both 50% and 80% thresholds for reduction in pain within 24 hours of facet injection with steroid and local anesthetic or medial branch block with local anesthetic only. These were the facet interventions used for our data collection. A Chi-square statistic was used to analyze categorical data and a Student's t-test was used to analyze non-categorical data. SPSS (IBM Corp. IBM SPSS Version 24.0) was used for all analyses.

RESULTS

Of our 112 patients, Group 1 consisted of 89 with an intervention occurring at the level with increased uptake on SPECT/CT. Group 2 consisted of 23 patients with an intervention at a level without uptake on SPECT/CT. Demographic data did not significantly differ between cohorts. A Chi-square test of independence demonstrated that intervention at a level concordant with SPECT/CT was significantly correlated with self-reported pain relief thresholds of both 50% and 80% (p=.0002).

CONCLUSIONS

Facet interventions based on SPECT/CT scan uptake were more successful in pain reduction than those which were not. This suggests a role for SPECT/CT in diagnosing therapeutic targets for neck pain.

Lower effectiveness of facet joint infiltration in patients with concurrent facet joint degeneration and active endplate changes

BACKGROUND CONTEXT

Facet joint degeneration (FJD) and disc degeneration (DD) with associated endplate (EP) changes, specifically Modic 1 changes, might occur concurrently and therefore pose a challenge in the treatment of lower back pain (LBP).

PURPOSE

The aim of the present study was to investigate if the presence of active EP changes (Modic 1) would alter the effect of facet joint infiltrations (FJI) for the treatment of concurrent FJD.

STUDY DESIGN

Prospective cohort study, Level III.

PATIENT SAMPLE

42 patients (Male:20, Female:22) with an average of 58±14 years with FJD on conventional magnetic resonance imaging (MRI) receiving a FJI for treatment of lower back pain were included.

OUTCOME MEASURES

The pain score at baseline, 15 min, 1 day, 1 week and 1 month following FJI as well as the reduction of pain were analyzed. Furthermore, active EP changes on conventional MRI and increased EP metabolic activity on PET/MRI were evaluated and compared.

METHODS

All the patients underwent a (18F)-NaF PET/MRI, conventional MRI and FJI for symptomatic FJD. Active EP changes on conventional MRI and increased EP metabolic activity on PET/MR were analyzed for conformity. The pain score as well as the pain reduction at the above-mentioned time points were compared between patients with and without increased EP metabolic activity in PET/MRI.

RESULTS

The LBP reduction was significantly different between patients with (n=20) and without (n=22) active EP changes at 15 minutes (1.3±2.4 vs. 2.9±2.4, p=.03) and 1 month (0.9±2.3 vs. 2.8±2.9, p<.001) following FJI. The minimal clinically important difference for LBP reduction was reached significantly more often in the absence of active EP changes (73%) compared with patients with active EP changes (35%) 1 month following FJI (p=.03).

CONCLUSIONS

FJI is less effective in LBP reduction of patients with FJD and concurrent active EP changes (eg Modic 1).

Consensus practice guidelines on interventions for lumbar facet joint pain from a multispecialty, international working group

BACKGROUND

The past two decades have witnessed a surge in the use of lumbar facet blocks and radiofrequency ablation (RFA) to treat low back pain (LBP), yet nearly all aspects of the procedures remain controversial.

METHODS

After approval by the Board of Directors of the American Society of Regional Anesthesia and Pain Medicine, letters were sent to a dozen pain societies, as well as representatives from the US Departments of Veterans Affairs and Defense. A steering committee was convened to select preliminary questions, which were revised by the full committee. Questions were assigned to 4-5 person modules, who worked with the Subcommittee Lead and Committee Chair on preliminary versions, which were sent to the full committee. We used a modified Delphi method, whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chair, who incorporated the comments and sent out revised versions until consensus was reached.

RESULTS

17 questions were selected for guideline development, with 100% consensus achieved by committee members on all topics. All societies except for one approved every recommendation, with one society dissenting on two questions (number of blocks and cut-off for a positive block before RFA), but approving the document. Specific questions that were addressed included the value of history and physical examination in selecting patients for blocks, the value of imaging in patient selection, whether conservative treatment should be used before injections, whether imaging is necessary for block performance, the diagnostic and prognostic value of medial branch blocks (MBB) and intra-articular (IA) injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for a prognostic block, how many blocks should be performed before RFA, how electrodes should be oriented, the evidence for larger lesions, whether stimulation should be used before RFA, ways to mitigate complications, if different standards should be applied to clinical practice and clinical trials and the evidence for repeating RFA (see table 12 for summary).

CONCLUSIONS

Lumbar medial branch RFA may provide benefit to well-selected individuals, with MBB being more predictive than IA injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of more false-negatives. Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

Predictors of Response to a Medial Branch Block: MRI Analysis of the Lumbar Spine

The aim of this study was to determine the association between radiologic spinal pathology and the response to medial branches block (MBB). This retrospective observational study compared 165 patients. A successful response was defined as ≥30% or a 2-point reduction in the numeric rating scale (NRS) compared with the baseline at the 1-month follow-up. The facet angle, facet angle difference, facet joint degeneration, disc height and spondylolisthesis grade were analyzed from an MRI at the L3 to S1 levels. Univariate and multivariate logistic regression analyses were used to evaluate independent factors associated with a successful response of MBB. In the univariate analysis, the disc height at L5-S1 and facet angle difference at L3-4 were lower in the positive responders (p = 0.022 and p = 0.087, respectively). In the multivariate analysis, the facet angle difference at L3-4 and disc height at L5-S1 were independent factors associated with a successful response (odds ratio = 0.948; p = 0.038 and odds ratio = 0.864; p = 0.038, respectively). In patients with a degenerative disc at L5-S1, MBB can lead to a good response for at least one month. In patients with facet tropism at L3-4 level, the response to MBB after one month is likely to be poor.

Effectiveness of Lumbar Facet Joint Blocks and Predictive Value before Radiofrequency Denervation: The Facet Treatment Study (FACTS), a Randomized, Controlled Clinical Trial

WHAT WE ALREADY KNOW ABOUT THIS TOPIC

WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: With facet interventions under scrutiny, the authors' objectives were to determine the effectiveness of different lumbar facet blocks and their ability to predict radiofrequency ablation outcomes.

METHODS

A total of 229 participants were randomized in a 2:2:1 ratio to receive intraarticular facet injections with bupivacaine and steroid, medial branch blocks, or saline. Those with a positive 1-month outcome (a 2-point or more reduction in average pain score) and score higher than 3 (positive satisfaction) on a 5-point satisfaction scale were followed up to 6 months. Participants in the intraarticular and medial branch block groups with a positive diagnostic block (50% or more relief) who experienced a negative outcome proceeded to the second phase and underwent radiofrequency ablation, while all saline group individuals underwent ablation. Coprimary outcome measures were average reduction in numerical rating scale pain score 1 month after the facet or saline blocks, and average numerical rating scale pain score 3 months after ablation.

RESULTS

Mean reduction in average numerical rating scale pain score at 1 month was 0.7 ± 1.6 in the intraarticular group, 0.7 ± 1.8 in the medial branch block group, and 0.7 ± 1.5 in the placebo group; P = 0.993. The proportions of positive blocks were higher in the intraarticular (54%) and medial branch (55%) groups than in the placebo group (30%; P = 0.01). Radiofrequency ablation was performed on 135 patients (45, 48, and 42 patients from the intraarticular, medial branch, and saline groups, respectively). The average numerical rating scale pain score at 3 months was 3.0 ± 2.0 in the intraarticular, 3.2 ± 2.5 in the medial branch, and 3.5 ± 1.9 in the control group (P = 0.493). At 3 months, the proportions of positive responders in the intraarticular, medial branch block, and placebo groups were 51%, 56%, and 24% for the intraarticular, medial branch, and placebo groups, respectively (P = 0.005).

CONCLUSIONS

This study establishes that facet blocks are not therapeutic. The higher responder rates in the treatment groups suggest a hypothesis that facet blocks might provide prognostic value before radiofrequency ablation.

Value of 18 F-FDG PET/MRI for the outcome of CT-guided facet block therapy in cervical facet syndrome: initial results

INTRODUCTION

The aim of this study was to evaluate the ability of ¹⁸ F-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging (¹⁸ F-FDG PET/MRI) to detect PET-positive cervical facet arthropathy and identify patients who benefit from facet block therapy.

METHODS

Ten patients with cervical facet syndrome (mean age: 65 ± 12 years) underwent ¹⁸ F-FDG PET/MRI of the neck. Focal ¹⁸ F-FDG uptake in PET-positive facet joints served as target for computed tomography (CT)-guided facet blocks. In PET-negative patients, the target joint for facet block therapy was selected by current clinical standards considering the level of maximum facet arthrosis and pain. Neck pain was measured on visual analogue scale (VAS) before and after therapy. Bone marrow signal intensity (SI) ratio on turbo inversion recovery magnitude (TIRM) images and maximum standard uptake values (SUVmax) was calculated for each facet joint. Pearson's correlation coefficient (r) was calculated between bone marrow SI ratios on TIRM and SUVmax.

RESULTS

¹⁸ F-FDG PET/MRI detected PET-positive facet arthropathy in six patients. Patients with PET-positive facet arthropathy had significantly less pain compared with the pretreatment pain 3 h (P = 0.002), 4 weeks (P = 0.002) and 3 months (P = 0.026) after facet block therapy. Pain did not change significantly in patients with PET-negative facet arthropathy. TIRM SI ratio was higher in PET-positive facet arthropathy than in PET-negative facet arthropathy (P < 0.001). Correlation was strong between bone marrow SI ratio on TIRM images and SUVmax (r = 0.7; P < 0.001).

CONCLUSIONS

¹⁸ F-FDG PET/MRI can detect PET-positive cervical facet arthropathy and help to identify patients benefitting from facet block therapy. Bone marrow TIRM SI ratio might be a surrogate for PET-positive facet arthropathy.

Sonoanatomic indices of lumbar facet joints in patients with facetogenic back pain in comparison to healthy subjects

BACKGROUND

Nowadays, ultrasound is increasingly used with a great accuracy in performing nerve blocks for facet joint disease.

OBJECTIVES

To measure sonoanatomic characteristics for the facet joints of lumbar vertebras in patients with facetogenic pain and healthy volunteers.

STUDY DESIGN

Cross-sectional, observational study.

SETTING

University-affiliated Specialty Clinic for Pain Management.

PATIENTS

Twenty patients with facet joint disease (FJD) and 40 healthy volunteers (HVGs) were matched for age and sex, height, and weight. Patients with FJD were referred with complaints of pain in the left lumbar facet joints that twice responded favorably to ultrasound guided medial branch blocks.

INTERVENTION

Medial branch blocks.

MEASUREMENT

The interfacet joint distance (IFJD) between the third, the fourth, and the fifth lumbar vertebras and their depth from the level of skin (DFS) were measured bilaterally, using a high-resolution ultrasound in both groups.

RESULTS

Thirty-one men and 29 women with average age of 41.5±9.5 years were enrolled. The IFJD for L3-L4 was 31.5±4.0 mm on the left side and 31.8±4.0 mm on the right side. The IFJD for L4-L5 was 31.3±4.4 mm on the left side and 31.5±4.0 mm on the right side. The IFJD was uniformly 2.2 mm shorter in the FJD group than those in the HVG group (P=.021). The measurements of DFS increased in lower vertebras (L3<L4<L5), bilaterally. With an exception of the left facet joints of L4 (P=.016), DFS measurements were similar in FJD and HVG groups.

LIMITATIONS

The diagnosis of facet joint disease was merely clinical and the total number of the patients was relatively small.

CONCLUSION

Interfacet distances of the lumbar vertebras are smaller in patients suffering from degenerative FJD compared with HVGs. Degenerative changes of intervertebral discs and partial reduction of space between 2 adjacent vertebras may contribute to this observation.

Ultrasound-Guided Approach for L5 Dorsal Ramus Block and Fluoroscopic Evaluation in Unpreselected Cadavers

BACKGROUND AND OBJECTIVES

Medial branch blocks are frequently performed to diagnose lumbar facet-joint-mediated pain. Ultrasound guidance can increase practicability and eliminate exposure to ionizing radiation when compared with fluoroscopy. However, ultrasound-guided L5 dorsal ramus block, which, together with L4 medial branch block is necessary to anesthetize the most commonly affected facet joint L5/S1, has not been described so far. The objective of this study was to develop a technique and to evaluate its accuracy with standard fluoroscopy in unpreselected cadavers.

METHODS

Twenty ultrasound-guided L5 dorsal ramus block approaches were performed with a new oblique out-of-plane technique in a rotated cross-axis view bilaterally in 10 cadavers. After checking the needle position in a second perpendicular sonographic plane, the final needle position was confirmed with conventional fluoroscopy by an independent observer.

RESULTS

All cadavers had significant degenerations of the lumbar spine, and 5 of them had moderate to severe spondylolisthesis. Skin-to-target distances were 42 ±7 mm. Sixteen L5 dorsal ramus block attempts were located at the exact radiological target, 1 was slightly too lateral, and 3 were slightly too caudal (3-10 mm away). The overall success rate in unpreselected cadavers reached 80% (95% confidence interval, 56%-94%) and in the subgroup of corpses without spondylolisthesis 100% (95% confidence interval, 69%-100%).

CONCLUSIONS

This is the first study to show that ultrasound-guided L5 dorsal ramus block is accurate and feasible in the absence of significant spondylolisthesis when performed with an oblique out-of-plane technique.

The value of SPECT/CT in localizing pain site and prediction of treatment response in patients with chronic low back pain

In many circumstances, causing sites of low back pain (LBP) cannot be determined only by anatomical imaging. Combined functional and morphological imaging such as bone scan with single-photon emission computed tomography/computed tomography (SPECT/CT) may be helpful in identifying active lesions. The purpose of this study was to evaluate the usefulness of bone SPECT/CT in localizing the pain site and the treatment of chronic LBP. One hundred seventy-five patients suffering from chronic LBP who underwent SPECT/CT were included, retrospectively. All of the patients received multiple general treatments according to the symptoms, and some of them underwent additional target-specific treatment based on SPECT/CT. Numerical rating scale (NRS) pain score was used to assess the pain intensity. Of 175 patients, 127 showed good response to the given therapies, while the rest did not. Overall, 79.4% of patients with definite active lesions showed good response. Patients with mild active or no lesions on SPECT/CT had relatively lower response rate of 63.0%. Good response was observed by the treatment with the guidance of active lesions identified on SPECT/CT. SPECT/CT could be useful in identifying active lesions in patients with chronic LBP and guiding the clinicians to use adequate treatment.

Frequency of discordance between facet joint activity on technetium Tc99m methylene diphosphonate SPECT/CT and selection for percutaneous treatment at a large multispecialty institution

BACKGROUND AND PURPOSE

The clinical impact of facet joint bone scan activity is not fully understood. The hypothesis of this study is that facet joints targeted for percutaneous treatment in clinical practice differ from those with reported activity on technetium Tc99m methylene diphosphonate SPECT/CT.

MATERIALS AND METHODS

All patients with a technetium Tc99m methylene diphosphonate SPECT/CT scan of the lumbar or cervical spine who underwent subsequent percutaneous facet joint steroid injection or comparative medial branch blocks at our institution between January 1, 2008, and February 19, 2013, were identified. Facet joints with increased activity were compared with those treated. A chart review characterized the clinical reasons for treatment discrepancies.

RESULTS

Of 74 patients meeting inclusion criteria, 52 (70%) had discrepant imaging findings and treatment selection of at least 1 facet joint, whereas 34 patients (46%) had a side (right vs left) discrepancy. Only 92 (70%) of 132 facet joints with increased activity were treated, whereas 103 (53%) of 195 of treated facet joints did not have increased activity. The most commonly documented clinical rationale for discrepancy was facet joint activity that was not thought to correlate with clinical findings, cited in 18 (35%) of 52 patients.

CONCLUSIONS

Facet joints undergoing targeted percutaneous treatment were frequently discordant with those demonstrating increased technetium Tc99m methylene diphosphonate activity identified by SPECT/CT at our institution, in many cases because the active facet joint(s) did not correlate with clinical findings. Further prospective double-blinded investigations of the clinical significance of facet joint activity by use of technetium Tc99m methylene diphosphonate SPECT/CT and comparative medial branch blocks are needed.