99mTc-DPD-SPECT/CT predicts the outcome of imaging-guided diagnostic anaesthetic injections: A prospective cohort study

The Value of SPECT-CT in Diagnosing Complex Non-Arthritic and Non-Neoplastic Conditions of the Foot and Ankle

INTRODUCTION

There is little information on the value of using single photon emission computerized tomography-computed tomography (SPECT-CT) in non-arthritic and non-neoplastic conditions of the foot and ankle (F&A). The vast majority of studies have investigated the role of SPECT-CT in degenerative conditions, bony pathology, and neoplastic conditions. The diagnostic value of SPECT-CT in purely non-arthritic and non-neoplastic conditions, in the absence of other conclusive radiological findings, is yet to be clarified. The aim of this study was to evaluate the value of SPECT-CT in a cohort of patients with complex F&A pathology, in whom diagnostic uncertainty existed after conventional imaging techniques, and to assess its added value in routine clinical practice.

METHODOLOGY

A retrospective analysis of 297 SPECT-CTs from 2010 to 2017 found 18 SPECT-CTs (age = 16-56 years) performed for non-arthritic F&A pathology. Changes in diagnosis, management, and clinical outcome scores were recorded before and after SPECT-CT imaging.

RESULTS

The results demonstrated that the provisional diagnosis was different from the SPECT-CT diagnosis in 10 (56%) out of the 18 patients and led to a modified treatment plan, which was successful in 8 (80%) out of the 10 patients. The post-intervention Manchester Oxford Foot Questionnaire (MOX-FQ) and Visual Analogue Scale (VAS) score improved from 76 ± 18 to 58 ± 24 (P = .02), and from 72 ± 17 to 49 ± 32 (P = .01), respectively. The SPECT-CT scan was useful in confirming the provisional diagnosis in the remaining 8 patients where a diagnostic uncertainty existed after conventional imaging techniques. Overall, a total of 15 out of 18 patients (83%) showed an improvement in their symptoms after management led by SPECT-CT diagnosis.

CONCLUSION

Our study highlights the added value of SPECT-CT in patients presenting with non-arthritic and non-neoplastic F&A conditions in which there is diagnostic uncertainty after conventional imaging. In 80% of cases, a change in management driven by the SPECT-CT findings led to a successful outcome. We have found SPECT-CT to be a useful investigative modality in assessing these complex F&A cases.

LEVELS OF EVIDENCE

Level IV.

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.

[Radiological-nuclear medicine hybrid diagnostics with SPECT/CT for chronic foot and ankle diseases : A new and important diagnostic tool]

BACKGROUND AND AIM

In contrast to standard methods (sonography, X‑ray, CT (computed tomography), MRI (magnetic resonance imaging), numerous diseases of the foot or ankle can be diagnosed using SPECT/CT (single photon emission computed tomography/computed tomography) with regard to their clinical relevance with high accuracy (up to > 90%). The aim of this review is to provide an up-to-date overview of the importance of SPECT/CT in selected diseases of the foot and ankle.

MATERIAL AND METHODS

A literature search was carried out in the Pubmed database using the following terms: SPECT/CT, SPECT, skeletal scintigraphy, CT, computed tomography, foot and ankle disease, OSG, tarsal root, foot pain. The publications were selected with regard to questions and diagnoses that frequently occur in foot and ankle diagnostics. Furthermore, papers that describe a more precise diagnosis, a change in therapy management or a reduction in symptoms due to the use of SPECT/CT were selected.

RESULTS

Several studies have shown that a focally increased bone metabolism in osteoarthritis and osteochondral lesions correlates significantly with the development of pain. The presence of symptomatic ossicles such as the os naviculare accessorium type II and os trigonum can be clearly demonstrated with the help of SPECT/CT and cannot be assigned as the source of the symptoms as accurately with any other imaging method. Bony reactions in the area of coalitions, arthrodesis, osteosynthesis, occult fractures, prostheses and diabetic foot cannot be detected with comparable accuracy using any other imaging method, so that therapy concepts in unclear cases, based only on standard imaging are changed in up to 2/3 of cases by SPECT/CT information.

DISCUSSION AND CONCLUSION

SPECT/CT is useful when there are clinical uncertainties despite standard imaging.

Diagnostic value of single-photon emission computed tomography-CT foot and ankle studies

AIM

The aim of this study is to determine the impact of foot and ankle single-photon emission computed tomography (SPECT) CT on patient management.

METHOD AND MATERIALS

A retrospective review over a 7-year period investigating whether the study identified or confirmed a source of symptoms. The electronic patient record was reviewed to see whether the test was helpful to the onward management of the patient.

RESULTS

In total 44 patients were included and pathology was identified in 40 of the 44 patients, with four having normal studies. SPECT CT was deemed helpful in the management of 39 of the patients with the positive usefulness overall calculated as 89%. The remaining five patients where the test was not helpful have been discussed.

CONCLUSION

SPECT-CT is a helpful imaging test in the diagnosis of foot and ankle disorders with 89% of studies being diagnostically useful.

The added value of SPECT/CT in the painful foot and ankle: A review of the literature

INTRODUCTION

Foot and ankle injuries are common. Radiographic assessment is difficult because of the complex anatomy. In the past decade SPECT/CT made its introduction in assessing bone pathology, it combines both morphologic and pathologic imaging in one image aiming to increase sensitivity and specificity when compared with MRI or CT alone. The purpose of this review was to provide a literature overview on the diagnostic value of SPECT/CT in foot and ankle pathology.

METHODS

A literature search was conducted in the databases of PubMed and EMBASE between January 2004 and September 2019 for articles describing the diagnostic value of SPECT/CT in foot and ankle pathology. For assessment of methodological quality of each study included in the analysis, QUADAS-2 checklist was used. Main outcomes were change of management, improved diagnosis and symptomatic improvement.

RESULTS

A total of eight studies were identified describing the diagnostic value of SPECT/CT in foot and ankle pathology based on patient data. The combined analysis shows that change of management and improved diagnosis occurred in 48-62% and 40-79% of the patients when compared with other imaging modalities and/or clinical assessment. Symptomatic improvement due to treatment based on SPECT/CT findings occurred in 92% of the patients.

CONCLUSION

SPECT/CT is useful when diagnosis based on other imaging modalities is inconclusive or when treatment based on these modalities does not lead to the desired symptomatic improvement.

Relevance of SPECT-CT in Complex Cases of Foot and Ankle Surgery: A Comparison With MRI

BACKGROUND

Finding the right diagnoses in patients with complex foot and ankle disorders can be challenging. Single-photon emission computed tomography and computed tomography (SPECT-CT) has shown to be feasible in foot and ankle surgery. The aim of this study was to evaluate the reliability and accuracy of SPECT-CT and thereby its impact on final treatment decision compared with magnetic resonance imaging (MRI).

METHODS

A retrospective study was performed on 49 patients treated at our institution. Experienced foot and ankle surgeons independently, and blinded, analyzed clinical data and radiographs together with MRI, SPECT-CT, or a combination of both. Based on the determined final treatment decision Cohen's kappa values were calculated to illustrate interrater and intrarater reliability.

RESULTS

The kappa values for interrater reliability were higher for SPECT-CT at .68 and MRI + SPECT-CT at .71 compared to 0.38 for MRI alone (P < .05). The kappa values for intrarater reliability of MRI + SPECT-CT were higher at .75 compared with SPECT-CT alone at .67 (P < .05) and MRI at .35 (P < .01).

CONCLUSION

We found a higher interrater and intrarater reliability for SPECT-CT compared with MRI alone for diagnosing complex foot and ankle pathologies. SPECT-CT has a high impact on final treatment decision. The main indications are bony pathologies with diagnostic uncertainty especially in closely adjacent structures as the joints of the midfoot, occult coalitio, stress fractures, verification or exclusion of nonfusion, periprosthetic disorders after total ankle replacement and osteochondral lesion in cases of combined pathologies.Levels of Evidence: Level IV: Retrospective study.

Bone SPECT/CT of the Foot and Ankle: Potential Clinical Application for Chronic Foot Pain

Diseases of the foot and ankle are common but relatively difficult to diagnose because of the complexity of the anatomy and the frequent occurrence of multiple diseases at the same time. For these reasons, management of chronic foot pain is often clinically challenging. MRI is the imaging modality of choice in many types of diseases causing chronic foot pain, due to high resolution and excellent soft tissue contrast. However, in the postoperative state, the use of MRI can be limited by artifact from metallic devices, and it may be difficult to confirm whether the pathology detected on the MRI is the actual cause of the pain. As bone scintigraphy provides metabolic information, it can help to find the origin of pain, and SPECT/CT can further improve the specificity by adding anatomical information. In daily clinical practice for management of foot and ankle pathologies, the use of bone SPECT/CT is gradually increasing. However, there has been limited evidence of usefulness of SPECT/CT in evaluating chronic foot pain. In this review article, the potential application of bone SPECT/CT for chronic foot pain is illustrated, and the role of SPECT/CT in the management of the foot and ankle diseases in clinical practice is described.

Central osteophytes develop in cartilage with abnormal structure and composition: data from the Osteoarthritis Initiative cohort

OBJECTIVE

To investigate the natural history of central osteophytes (COs) by analyzing the structure and matrix composition of CO-associated cartilage using 3-T MRI at and 1-3 years before the onset of COs.

MATERIALS AND METHODS

Baseline, 4- and 6-year knee MRIs of 400 participants in the Osteoarthritis Initiative were screened for the appearance of new COs. Twenty-eight subjects developed 31 COs. Using MRIs at CO onset and 1-3 years before CO onset, cartilage T2 values were calculated for the local cartilage preceding COs and the surrounding cartilage. Cartilage lesions local to the site of COs and bone marrow edema like lesions (BMELs) subjacent to COs were graded using whole organ MRI scores (WORMS). Wilcoxon tests were used to compare T2 values from the local and the surrounding cartilage at each time point and to compare T2 and WORMS between time points. Knee symptoms were recorded during this period.

RESULTS

All subjects showed local cartilage lesions before the development of COs. Mean cartilage WORMS increased from 1.56 ± 0.66 a period of 3 years before to 2.39 ± 0.75 with onset of COs (p = 0.008). Local T2 values in the area of the later-appearing COs were significantly higher compared with T2 values of the surrounding cartilage 3 (p = 0.044) and 2 years earlier (p = 0.031) and with the onset of COs (p = 0.025). No significant increase in symptoms was found with the onset of COs.

CONCLUSION

This study provides evidence that focal cartilage structural and compositional degeneration precedes COs. No significant aggravation of knee symptoms was reported during the evolution of COs.

99mTc-DPD SPECT/CT for localisation of inflammatory and chronic osteoarthritis of the foot and ankle

Aim: The precise localisation of osteoarthritic and inflammatory changes is crucial for selective treatment planning of radiosynovectomy (RSV). The present study evaluated the diagnostic accuracy of planar bone imaging and SPECT for the detection of pathological bone metabolism and inflammation in joints of the foot and ankle, compared with SPECT/CT. Patients, methods: 39 patients (mean age 65.6 ± 11.1 years) with suspected inflammatory osteoarthritis underwent SPECT/CT of the feet. After injection of approximately 500 MBq 99mTc DPD, all patients had three-phase planar bone imaging and late-phase hybrid SPECT/CT. late-phase SPECT, and CT of the foot. Increased bone metabolism and blood-pool was assigned to the respective joint of the fore-, mid-, and hindfoot, using SPECT/CT as the reference standard. Results: Overall, SPECT had a higher sensitivity than planar imaging (0.80 vs 0.68, n.s.). The advantage of SPECT was most obvious in the anatomically complex midfoot area (0.63 vs 0.26, p < 0.05) and less obvious in the forefoot (0.85 vs 0.79, n.s.) and hindfoot (0.89 vs 0.89, n.s.). The overall concordance (Cohen`s Kappa) between SPECT/CT and planar (late-phase) imaging and SPECT was high for the forefoot and the hindfoot (planar: 0.78/0.81; SPECT 0.86/0.88) and comparatively low for the midfoot (planar: 0.27; SPECT 0.61). Conclusion: SPECT was significantly superior to planar bone imaging for the detection of joint lesions in the midfoot. The differences between SPECT and planar imaging in the fore- and hindfoot were not significant, most likely due to the inherently less complex anatomy. Compared with SPECT alone, a benefit from the use of SPECT/CT can be observed in the midfoot region where it facilitates the identification of the correct joint for RSV.

Technetium-99m Methylene Diphosphonate Single-photon Emission Computed Tomography/Computed Tomography of the Foot and Ankle

The complex anatomy and function of the foot and ankle can make it difficult to determine the cause of symptoms in patients with foot and ankle pathology. Following initial clinical and radiographic assessment, additional imaging with magnetic resonance imaging may be required, which is often seen as the modality of choice. Although sensitive to pathological changes in bone metabolism and vascularity, technetium-99m (Tc-99m) bone scintigraphy often lacks the specificity and resolution required to evaluate the structures of the foot and ankle. Tc-99m methylene diphosphonate single-photon emission computed tomography/computed tomography (SPECT/CT) combines this sensitivity with the superior anatomical detail of CT, enabling better localization of pathological uptake and evaluation of associated structural changes. As a result, SPECT/CT has been growing in popularity for the assessment of patients with foot and ankle pathology where it can provide additional information that may change the initial diagnosis and subsequent management plan. Studies have reported modification of the surgical approach and site of intra-articular local anesthetic injections following SPECT/CT with good results. Interpretation of SPECT/CT studies requires an understanding of the pathological changes that result in increased tracer accumulation in addition to the CT changes that may be seen. This review aims to highlight the advantages of SPECT/CT, potential applications and explain the imaging appearances of common pathologies that may be observed.

Intra- and inter-observer reliability of a new standardized diagnostic method using SPECT/CT in patients with osteochondral lesions of the ankle joint

Background

Single Photon Emission Computed Tomography-Computed Tomography (SPECT/CT) gains an important part of diagnostics in patients with osteochondral lesions (OCL). SPECT/CT is a hybrid imaging modality, which combines a 3D scintigraphy (SPECT) and computerized tomography (CT) into one single procedure and combines metabolic data, structural and mechanical information.

The purpose of the study was to develop and evaluate a standardized method to anatomically localize and quantitatively analyze the bone SPECT tracer activity of the ankle joint using SPECT/CT.

Methods

OCL on the talus were diagnosed in 16 patients by 99mTc-HDP-SPECT/CT and MRI by specialized orthopedic surgeons and radiologists and retrospectively included. The articular superior surface of the talus was subdivided in six anatomical regions (T1–T6).

Using customized software, absolute bone SPECT values for each anatomical area were analyzed. Relative bone tracer uptake was calculated in relation to specific reference regions representing bone SPECT tracer background activity. All measurements were performed twice by two independent observers, blinded to clinical information. Intraclass correlation coefficients (ICC) were calculated for inter- and intra-observer reliability. The intraclass correlation coefficients (ICC) showed an excellent inter- and intra-observer reliability.

Results

The intraclass correlation coefficients (ICC) of all six regions are between 1.00 and 0.84 which is defined as very good. Results from region T1 to T6 impair slightly due to measurement regime.

All ICCs of observer 1 were nearly the same as the results of observer 2 in all regions.

Conclusion

The presented standardized SPECT/CT algorithm is clinically feasible and showed high inter- and intra-observer reliability. It might help to better understand the complex pathology of OCL on the talar dome. The major potential benefit of SPECT/CT is the assessment of the subchondral bone plate and the subchondral bone.

Pitfalls and Limitations of Radionuclide Planar and Hybrid Bone Imaging

The radionuclide (99m)Tc-MDP bone scan is one of the most commonly performed nuclear medicine studies and helps in the diagnosis of different pathologies relating to the musculoskeletal system. With its increasing utility in clinical practice, it becomes more important to be aware of various limitations of this imaging modality to avoid false interpretation. It is necessary to be able to recognize various technical, radiopharmaceutical, and patient-related artifacts that can occur while carrying out a bone scan. Furthermore, several normal variations of tracer uptake may mimic pathology and should be interpreted cautiously. There is an important limitation of a bone scan in metastatic disease evaluation as the inherent mechanism of tracer uptake is not specific for tumor but primarily relies on an osteoblastic response. Thus, it is crucial to keep in mind uptake in benign lesions, which can resemble malignant pathologies. The utility of a planar bone scan in benign orthopedic diseases, especially at sites with complex anatomy, is limited owing to lack of precise anatomical information. SPECT/CT has been significantly helpful in these cases. With wider use of PET/CT and reintroduction of the (18)F-fluoride bone scan, increasing knowledge of potential pitfalls on an (18)F-fluoride bone scan and (18)F-FDG-PET/CT will help in improving the accuracy of clinical reports.

Increased Osseous (99m)Tc-DPD Uptake in End-Stage Ankle Osteoarthritis: Correlation Between SPECT-CT Imaging and Histologic Findings

BACKGROUND

We analyzed the histopathologic findings in end-stage osteoarthritic ankle joint tissue that display increased uptake of bone-seeking radiotracer in single-photon emission computed tomography-computed tomography (SPECT-CT) imaging.

METHODS

Six consecutive patients with end-stage osteoarthritis undergoing total ankle replacement received preoperative SPECT-CT imaging using (99m)Technetium dicarboxypropane diphosphonate ((99m)Tc-DPD). Using imaging data for stratification, osteochondral tissue sections were prepared from SPECT-positive (+) and -negative (-) areas of tibial and talar resection specimens. Histomorphometric analyses of osteoblast numbers, collagen deposition, and cartilage degeneration were performed on hematoxylin and eosin, van Gieson's and Safranin-O stained tissue sections. Osteoclast activity was visualized using tartrate-resistant acid phosphatase (TRAP) staining.

RESULTS

Increased (99m)Tc-DPD uptake was observed exclusively subjacent to the subchondral bone plate of tibial and talar joint compartments. SPECT(-) tissues displayed typical fatty marrow morphology containing mainly collagen-positive blood vessels and few marrow and bone-lining cells. SPECT(+) tissues were characterized by increased numbers of active bone-lining osteoblasts depositing collagen fibers. Collagen area fraction of subchondral bone marrow was significantly increased in SPECT(+) (0.52 ± 0.21) compared with SPECT(-) (0.29 ± 0.13) tissues (P = .30). Multinucleated TRAP(+) osteoclasts were absent from bone formation sites, but associated with vascular structures invading articular cartilage through the subchondral bone plate. Increased (99m)Tc-DPD uptake was specifically and strongly correlated with increased osteoblast numbers (P = .011), and with collagen area fraction (P = .030) but not with Mankin score (P = .202), or with osteoclast number (P = .576).

CONCLUSION

Subchondral bone tissues in SPECT(+) areas of end-stage ankle osteoarthritis were histologically characterized by increased osteoblast-mediated bone formation in the absence of functional osteoclasts, and increased cellularity and collagen deposition in marrow tissues.

CLINICAL SIGNIFICANCE

Our findings suggest a pathologic bone-remodeling process in end-stage ankle OA areas with increased (99m)Tc-DPD uptake.

99mTc-HDP SPECT-CT Aids Localization of Joint Injections in Degenerative Joint Disease of the Foot and Ankle

BACKGROUND

Pain relating to degenerative joint disease within the foot and ankle can be difficult to localize with clinical examination alone due to the complex anatomy of the joints. The aim of this study was to determine whether single-photon emission computed tomography combined with conventional computed tomography (SPECT-CT) could be used to localize the site of degenerative joint disease for intra-articular injection and thereby improve the clinical success of the procedure.

METHODS

A prospective study was performed involving 203 patients who had undergone triple-phase (99m)Tc-hydroxymethylene diphosphonate bone scans with SPECT-CT of the foot and ankle for degenerative joint disease. Fifty-two patients went on to have joint injections for degenerative joint disease, with clinical follow-up. Correlation with the clinical diagnosis and the outcome of intra-articular injections with 0.5% bupivacaine and 80 mg of Depo-Medrone was performed. A successful outcome was determined by an improvement in the visual analog pain score of at least 50%.

RESULTS

In 19 (37%) patients, the site of degenerative joint disease determined by SPECT-CT differed from the initial clinical assessment and resulted in a change in management. Overall, 46 (88%) patients showed an improvement in symptoms.

CONCLUSION

The study demonstrated a high clinical success rate for SPECT-CT-guided joint injections. The technique was useful in localizing degenerative joint disease of the ankle, hindfoot, and midfoot as an adjunct to clinical examination.

LEVEL OF EVIDENCE

Level IV, case series.

Correlation of (99m) Tc-DPD SPECT/CT Scan Findings and Diagnostic Blockades of Lumbar Medial Branches in Patients with Unspecific Low Back Pain in a Randomized-Controlled Trial

OBJECTIVE

Zygapophyseal joints are the origin of pain in up to 30% of those with unspecific chronic low back pain. Until recently, no reliable clinical tests have been found to identify the patients who would benefit from denervation of the zygapophyseal joints by medial branch blockades.

DESIGN

We performed a prospective randomized placebo-controlled trial to evaluate the value of high-resolution single-photon emission computed tomography (SPECT)/computed tomography (CT) of the lumbar spine prior to any diagnostic infiltration of the medial branches.

METHODS

Patients with suspected zygapophyseal joint-related pain were included in the study. After obtaining a SPECT/CT scan of the lumbar spine a set of infiltrations of the medial branches was done with local anesthetics and placebo on different days. Patients and anesthetists were blinded to the results of SPECT/CT and to the infiltrated agents.

RESULTS

In a total of 29 study patients, 7 had positive and 22 negative infiltration tests, and 9 had positive and 20 negative SPECT/CT findings. Sensitivity of SPECT/CT for a positive response after diagnostic infiltration was 0.57 (95% confidence interval [CI] 0.18-0.90); specificity was 0.77 (CI 95% 0.55-0.92); odds ratio was 4.53 (CI 95% 0.75-27.40); and diagnostic accuracy was 0.72.

CONCLUSION

Compared with diagnostic infiltrations SPECT/CT scans showed only a moderate sensitivity and specificity and, therefore, may not be recommended as a first line diagnostic tool prior to diagnostic infiltrations.

Comparison of SPECT/CT and MRI in diagnosing symptomatic lesions in ankle and foot pain patients: diagnostic performance and relation to lesion type

Purpose

The purpose of this study was to compare the diagnostic performance of SPECT/CT and MRI in patients with ankle and foot pain, with regard to the lesion types.

Materials and Methods

Fifty consecutive patients with ankle and foot pain, who underwent ^99mTc-MDP SPECT/CT and MRI, were retrospectively enrolled in this study. Symptomatic lesions were determined based on clinical examination and response to treatment. On MRI and SPECT/CT, detected lesions were classified as bone, ligament/tendon, and joint lesions. Uptake on SPECT/CT was assessed using a 4-grade system. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of SPECT/CT and MRI were evaluated in all detected lesions and each lesion type. Diagnostic value of uptake grade was analyzed using receiver-operating characteristics (ROC) curve analysis, and diagnostic performance was compared using Chi-square or McNemar tests.

Results

In overall lesions, the sensitivity, PPV and NPV of SPECT/CT for symptomatic lesions were 93%, 56%, 91%, and they were 98%, 48%, 95% for MRI. There was no significant difference between SPECT/CT and MRI. However, the specificity of SPECT/CT was significantly higher than that of MRI (48% versus 24%, P = 0.016). Uptake grade on SPECT/CT was significantly higher in symptomatic lesions (P < 0.001), and its area under curve on ROC analysis was 0.787. In the analysis of each lesion type, the specificity of SPECT/CT was poor in joint lesions compared with other lesion types and MRI (P < 0.001, respectively). MRI exhibited lower specificity than SPECT/CT in bone lesions (P = 0.004) and ligament/tendon lesions (P < 0.001).

Conclusions

SPECT/CT has MRI-comparable diagnostic performance for symptomatic lesions in ankle and foot pain patients. SPECT/CT and MRI exhibit different diagnostic specificity in different lesion types. SPECT/CT may be used as a complementary imaging method to MRI for enhancing diagnostic specificity.

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.

Influence on therapeutic decision making of SPECT-CT for different regions of the foot and ankle

Background. Single-photon emission computed tomography and computed tomography (SPECT-CT) has a high impact on diagnosis and treatment decision of different joints. The aim of this study was to evaluate whether there is a different gain of SPECT-CT for different foot regions. Material and Methods. We retrospectively identified 86 patients who received a SPECT-CT of the foot and ankle between April 2011 and December 2012. We divided all patients into the following subgroups: ankle (group 1), subtalar (group 2), Chopart (group 3), and Lisfranc (group 4). The local ethical committee approved the study. Results. The clinical treatment decision was changed based on SPECT-CT results in 64.5% of group 1, 65.2% of group 2, and 75% each of groups 3 and 4. Eighty patients (93%) had pain relief after treatment based on SPECT-CT. The overall SPECT-CT sensitivity was 0.94 and the specificity was 0.57. The positive and negative predictive values were 0.87 and 0.75, respectively. Conclusion. The impact of SPECT-CT on treatment decision is slightly higher in diseases of the Chopart and Lisfranc joints than in the upper ankle and subtalar joints. The additional information has a clinical relevance due to the high rate of pain relief by treatment based on SPECT-CT diagnosis.

Revision Subtalar Joint Fusion With a Porous Metal Spacer and an Intramedullary Nail: A Case Report

Nonunion of hindfoot arthrodesis can be difficult to successfully treat and will often require bone graft techniques. Large amounts of autogenous bone graft can be difficult to procure and will be associated with donor site morbidity. The use of porous metal implants has been shown to satisfactorily bridge segmental bone defects and to work in conjunction with allogeneic bone graft material, without the risks associated with autogenous bone graft donor site morbidity. The purpose of the present report is to describe the use of a perforated, porous metal implant combined with an intramedullary nail for revision surgery of failed subtalar joint fusion in an adult female patient.

Supramalleolar osteotomies for degenerative joint disease of the ankle joint: indication, technique and results

Patients with varus or valgus hindfoot deformities usually present with asymmetric ankle osteoarthritis. In-vitro biomechanical studies have shown that varus or valgus hindfoot deformity may lead to altered load distribution in the tibiotalar joint which may result in medial (varus) or lateral (valgus) tibiotalar joint degeneration in the short or medium term. The treatment of asymmetric ankle osteoarthritis remains challenging, because more than half of the tibiotalar joint surface is usually preserved. Therefore, joint-sacrificing procedures like total ankle replacement or ankle arthrodesis may not be the most appropriate treatment options. The shortand midterm results following realignment surgery, are very promising with substantial pain relief and functional improvement observed post-operatively. In this review article we describe the indications, surgical techniques, and results from of realignment surgery of the ankle joint in the current literature.

Ankle osteoarthritis: etiology, diagnostics, and classification

Osteoarthritis (OA) is defined as the syndrome of joint pain and dysfunction caused by substantial joint degeneration. In general, OA is the most common joint disease and is one of the most frequent and symptomatic health problems for middle-aged and older people: OA disables more than 10% of people who are older than 60 years. This article reviews the etiology of ankle OA, and describes the onset and development of posttraumatic ankle OA, the most common form of OA in the tibiotalar joint. Various methods of clinical and radiographic assessment are described in detail.

Joint-preserving surgery of valgus ankle osteoarthritis

Patients with posttraumatic ankle osteoarthritis (OA) typically present with asymmetric involvement of the tibiotalar joint, resulting in valgus or varus deformity of the ankle and hindfoot. Without appropriate treatment, patients with asymmetric ankle OA typically develop full end-stage ankle OA. Ankles with valgus deformities suffer from a lateral joint overload with subsequent lateral tibiotalar joint degeneration, which causes further lateral load shift. In these cases patients may benefit from joint-preserving realignment surgery to unload the degenerated lateral area and normalize joint biomechanics. This article describes the authors' algorithm for the treatment of patients with asymmetric valgus ankle OA.

The diagnostic value of single photon-emission computed tomography bone scans combined with CT (SPECT-CT) in diseases of the foot and ankle

BACKGROUND

A radionuclide bone scan with single photon-emission computed tomography and CT (SPECT-CT) is a new imaging modality which combines highly detailed CT with the functional information from a triple phase radionuclide bone scan. Little has been published about its diagnostic accuracy and usefulness in foot and ankle pathology. The aim of this study is to evaluate whether bone scans with SPECT-CT provide a useful contribution to the management of patients with foot and ankle pain, and whether it results in changes to clinical management.

METHODS

A retrospective study involving 50 patients was conducted between March 2010 and April 2011. SPECT-CT was requested in cases where definitive clinical diagnosis could not be achieved after clinical examination and plain radiography. Pathology as highlighted on SPECT-CT was taken as the definitive diagnosis in these patients and was treated accordingly. Patients were subsequently seen in the follow up clinic to evaluate the outcome of their treatment.

RESULTS

In 11 patients (22%), the provisional clinical diagnosis matched with the findings of the SPECT-CT and no change in treatment was necessary. In 39 patients (78%) the findings of the SPECT-CT did not correlate exactly with the initial clinical diagnosis and led to a modified treatment plan. The accuracy, sensitivity, specificity, positive predictive and negative predictive value of SPECT-CT in this series was 94%, 95.45%, 83.3%, 97.6% and 71.43% respectively.

CONCLUSIONS

SPECT-CT is a useful investigation tool in foot and ankle pathologies. The present study shows a high diagnostic accuracy and we recommend its use in cases with diagnostic uncertainty.

Revision of failed osteochondral autologous transplantation procedure for chronic talus osteochondral lesion with iliac crest graft and autologous matrix-induced chondrogenesis: a case report

This article describes a novel technique for treatment of recurrent large osteochondral lesions of the talus using autologous matrix-induced chondrogenesis with a collagen I/III matrix.

Percutaneous foot joint needle placement using a C-arm flat-panel detector CT

PURPOSE

Image guidance is valuable for diagnostic injections in foot orthopaedics. Flat-detector computed tomography (FD-CT) was implemented using a C-arm, and the system was tested for needle guidance in foot joint injections.

METHODS

FD-CT-guided joint infiltration was performed in 6 patients referred from the orthopaedic department for diagnostic foot injections. All interventions were performed utilising a flat-panel fluoroscopy system utilising specialised image guidance and planning software. Successful infiltration was defined by localisation of contrast media depot in the targeted joint. The pre- and post-interventional numeric analogue scale (NAS) pain score was assessed.

RESULTS

All injections were technically successful. Contrast media deposit was documented in all targeted joints. Significant relief of symptoms was noted by all 6 participants.

CONCLUSIONS

FD-CT-guided joint infiltration is a feasible method for diagnostic infiltration of midfoot and hindfoot joints. The FD-CT approach may become an alternative to commonly used 2D-fluoroscopically guidance.