Imaging of Spondylodiscitis: A Comprehensive Updated Review-Multimodality Imaging Findings, Differential Diagnosis, and Specific Microorganisms Detection.

Spondylodiscitis is defined by infectious conditions involving the vertebral column. The incidence of the disease has constantly increased over the last decades. Imaging plays a key role in each phase of the disease. Indeed, radiological tools are fundamental in (i) the initial diagnostic recognition of spondylodiscitis, (ii) the differentiation against inflammatory, degenerative, or calcific etiologies, (iii) the disease staging, as well as (iv) to provide clues to orient towards the microorganisms involved. This latter aim can be achieved with a mini-invasive procedure (e.g., CT-guided biopsy) or can be non-invasively supposed by the analysis of the CT, positron emission tomography (PET) CT, or MRI features displayed. Hence, this comprehensive review aims to summarize all the multimodality imaging features of spondylodiscitis. This, with the goal of serving as a reference for Physicians (infectious disease specialists, spine surgeons, radiologists) involved in the care of these patients. Nonetheless, this review article may offer starting points for future research articles.

MRI and spondyloarthropathy: diagnostic performance compared to long-term clinical follow-up with evaluation of gadolinium chelates injection.

OBJECTIVES: To evaluate MRI performance on both initial and long-term rheumatologic diagnosis of spondyloarthritis (SpA), taking into account clinical evolution and treatment response, and the impact of gadolinium injection. METHODS: In this single-center study, patients who underwent both spinal and sacroiliac (SI) joint MRI were prospectively recruited between May 2013 and January 2014 and followed for 7 years until 2020. Clinical, biological, and radiologic parameters were collected. At 7-year follow-up (2020), two independent readers reevaluated the initial MRI datasets for specific radiological features of SpA with a 5-point Likert scale to record the estimation of confidence. The centralized MRI interpretations were compared to the established rheumatologic diagnoses in 2013 and 2020. RESULTS: In total, 145 patients (52 men and 93 women) were included. During the 7-year follow-up, the number of patients with positive SpA diagnosis decreased from 93 to 58. Mean sensitivity, specificity, and accuracy of non-contrast MRI were 18, 97, and 49% and 27, 97, and 69% considering 2013 and 2020 rheumatologic diagnoses, respectively. Mean sensitivity, specificity, and accuracy values of gadolinium-enhanced MRI were 26, 97, and 54% and 38, 97, and 73% considering 2013 and 2020 diagnoses, respectively. Post-contrast MRI enabled identification of a subgroup of enthesis-only lesions, without any bone lesions, corresponding to 14% of the pathological cohort. It confirmed uncertain diagnoses in an additional 8.5% of pathological cases. CONCLUSIONS: MRI performance for SpA diagnosis is higher when long-term clinical follow-up is considered than when compared to initial diagnosis. Gadolinium injection increases MRI diagnostic performance and may demonstrate a pure enthesic form of the disease, without bone abnormality. KEY POINTS: • Compared to the rheumatologist's diagnosis over long-term clinical follow-up, MRI performance for SpA is higher than usually estimated. • Gadolinium injection increases diagnostic performance of MRI as it may identify a purely enthesis form of the disease. • Gadolinium injection should be discussed in patients for whom the diagnostic suspicion is strong and whose initial non-injected examination is normal or doubtful.

Three-dimensional ultrashort echo time (3D UTE) magnetic resonance imaging (MRI) of the normal and degenerative disco-vertebral complex at 4.7 T: a feasibility study with longitudinal evaluation.

OBJECTIVES: To assess feasibility of a three-dimensional ultrashort echo time (3D-UTE)-sequence to evaluate normal and pathological disco-vertebral complex (DVC), with assessment of its different portions in a rat model of degenerative disk disease (DDD) with histological correlation. To assess whether this sequence, in comparison with long echo time T2-weighted sequence, is able to monitor DDD with differentiation of early from chronic DVC changes in pathological mechanical conditions. METHODS: Five rats were induced with DDD model by percutaneous disk trituration of the tail with an 18-G needle under US-guidance and imaged at 4.7 T. MRI protocol included fat-saturated-T2 (RARE) and 3D-UTE-sequences performed at baseline (day 0. n = 5 animals /10 DVC) and each week (W) from W1 to W10 postoperatively. Visual analysis and signal intensity measurements of SNR and CNR of all DVC portions were performed on RARE and UTE images. Following killing (baseline, n = 1/2 DVC; W2, n = 2/4 DVC; W10, n = 2/4 DVC), histological analysis was performed and compared with MRI. RESULTS: In normal DVC, unlike conventional RARE-sequences, 3D-UTE allowed complete identification of DVC zonal anatomy including on visual analysis and CNR measurements. In pathological conditions, SNR and CNR measurements of the annulus fibrosus and nucleus pulposus on 3D-UTE distinguished early discitis at W1 from chronic discopathy (P < 0.001 for SNR and P < 0.001 for CNR). Neither the normal complete anatomy of the DVC nor its pathological patterns could be assessed on conventional sequences. CONCLUSIONS: Unlike conventional sequences, 3D-UTE enables visualization of the complete normal DVC anatomy and enables monitoring of DDD differentiating between early DVC changes from chronic ones. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Innovative Spine Implants for Improved Augmentation and Stability in Neoplastic Vertebral Compression Fracture.

Background and objectives: Tumor-related vertebral compression fractures often result in severe back pain as well as progressive neurologic impairment and additional morbidities. The fixation of these fractures is essential to obtain good pain relief and to improve the patients' quality of life. Thus far, several spine implants have been developed and studied. The aims of this review were to describe the implants and the techniques proposed to treat cancer-related vertebral compression fractures and to compile their safety and efficacy results. Materials and Methods: A systematic MEDLINE/PubMed literature search was performed, time period included articles published between January 2000 and March 2019. Original articles were selected based on their clinical relevance. Results: Four studies of interest and other cited references were analyzed. These studies reported significant pain and function improvement as well as kyphotic angle and vertebral height restoration and maintain for every implant and technique investigated. Conclusions: Although good clinical performance is reported on these devices, the small numbers of studies and patients investigated draw the need for further larger evaluation before drawing a definitive treatment decision tree to guide physicians managing patients presenting with neoplastic vertebral compression fracture.

Early Achilles Enthesis Involvement in a Murine Model of Spondyloarthropathy: Morphological Imaging with Ultrashort Echo-Time Sequences and Ultrasmall Superparamagnetic Iron Oxide (USPIO) Particle Evaluation in Macrophagic Detection.

Purpose: To confirm the interest of 3-dimensional ultrashort echo-time (3D-UTE) sequences to assess morphologic aspects in normal and pathological Achilles entheses in a rat model of spondyloarthropathy (SpA) with histological correlations, in comparison with conventional RARE T2 Fat-Sat sequences, and, furthermore, to evaluate the feasibility of a 3D multiecho UTE sequence performed before and after the intravenous injection of ultrasmall superparamagnetic iron oxide (USPIO) particles to assess macrophagic involvement in the Achilles enthesis in the same rat model of SpA. Materials and Methods: Fourteen rats underwent in vivo MRI of the ankle at 4.7 T, including a 3D RARE T2 Fat-Sat sequence and a 3D ultrashort echo-time (UTE) sequence for morphologic assessment at baseline and day 3 after induction of an SpA model, leading to Achilles enthesopathy in the left paw (right paw serving as a control). A 3D multiecho UTE sequence was also performed at day 3 before and then 24 (4 rats) and 48 (2 rats) hours after intravenous injection of USPIO. Visual analysis and signal intensity measurements of all images were performed at different locations of the Achilles enthesis and preinsertional area. Visual analysis and T2∗ measurements were performed before and after USPIO injection, on the 3D multiecho UTE sequence in the same locations. Normal and pathological values were compared by Wilcoxon signed-rank tests. MR findings were compared against histological data. Results: 3D-UTE sequences enabled morphologic identification of the anterior fibrocartilage and posterior collagenic areas of the Achilles enthesis. Visual analysis and signal intensity measurements distinguished SpA-affected entheses from healthy ones at day 3 (P=0.02). After administration of USPIO, no differences in signals were detected. Similarly, both visual analysis and signal T2∗ measurements in the enthesis were unable to distinguish the SpA-affected tendons from healthy ones (P=0.914). Neither the normal anatomy of the enthesis nor its pathological pattern could be distinguished using the standard RARE sequence. Histology confirmed the absence of USPIO in Achilles entheses, despite marked signs of inflammation. Conclusion: Unlike conventional RARE T2 Fat-Sat sequences, 3D-UTE sequences enable morphologic assessment of normal enthesis anatomy and early detection of abnormalities in pathological conditions. However, 3D multiecho UTE sequences combined with USPIO injections with T2∗ measurements were unable to detect macrophagic involvement in these pathological conditions.

Symptomatic Schmorl's nodes: role of percutaneous vertebroplasty. Open study on 52 patients.

PURPOSE: To assess the feasibility and clinical outcome of combined CT and fluoroscopy-guided percutaneous vertebroplasty in the management of painful Schmorl's nodes (SN). METHODS: A prospective study was carried out from January 2014 to January 2016 in 52 consecutive patients. Thirty-two men and 30 women aged between 42 and 88 years old were consecutively included. Technical success was defined as the ability to deposit cement in the subchondral endplate anteriorly, around the SN and posteriorly to the SN, in a cupule-like shape. Data regarding procedure time, amount of cement injection, and cement leakage were also noted. Assessment of pain was performed with VAS score and Oswestry disability index. All patients underwent a clinical and radiological follow-up at 1 day, 1 month, 6 months, and 1 year after procedure. RESULTS: Technical success was 100%. Mean procedural time was 15 min, and mean injected cement volume was 2.8 mL. The VAS and Oswestry disability index decreased respectively from 7.2 ± 1.5 to 2.1 ± 1.0 and from 59.2 ± 16.2 to 17.1 ± 5.0 at 1 month. Follow-up mean VAS scores were 2.4 (± 1.4) at 6 months and 2.2 (± 1.2) at 12 months. CONCLUSION: PVP appears as a feasible procedure in patients with painful SN with satisfying pain decrease in the following year after procedure.

Contained Herniated Lumbar Disc: CT- and Fluoroscopy-Guided Automated Percutaneous Discectomy-A Revival.

The combination of a new device and dual guidance (computed tomography [CT] and fluoroscopy) is similar to other percutaneous devices in achieving a mechanical decompression of the disc. The difference, however, is that the target of the decompression with the current technique is the herniated disc itself. The goal of this combined technique is to create a space, an "olive" around the probe, allowing a decrease in pressure inside the hernia. Percutaneous discectomy under combined CT and fluoroscopic guidance is a minimally invasive spine surgery that should be considered as an alternative to surgery in properly selected patients.

Treatment of spinal metastases in renal cell carcinoma: A critical review.

Kidney cancer is the 9th most common cancer in men and the 14th most common in women worldwide. Renal cell carcinoma (RCC) constitutes 90% of all malignancies of the kidney. RCC, is known to be highly vascular and relatively radioresistant. Bone metastases are one of the most common metastatic sites and occur in around 30% of RCCs. They significantly impact the quality of life of patients causing pain and pathological fractures. Spinal metastases represent a particular case with regard to symptoms and treatment. Indeed, neurological pain is often added to the nociceptive pain caused by metastases. More importantly, neurological impairment can be seen, caused by spinal cord or nerve root compression (MSCC). Due to close contact with the spinal cord, the treatment of spinal bone metastases is challenging and requires a multidisciplinary approach. Specific treatment is currently focused on 4 main avenues which are surgery, radiotherapy, interventional radiology and systemic treatment. In June 2017 we carried out an extensive search on PubMed, Web of Science, and Cochrane Library to review the various treatment options and to establish a treatment strategy. This article presents the result of our critical review of the literature, given our expertise in the field.

An open-label, prospective, observational study of the efficacy of bisphosphonate therapy for painful osteoid osteoma.

OBJECTIVES: To assess the efficacy of bisphosphonate therapy on bone pain in patients with osteoid osteoma (OO) (main objective), and to describe bisphosphonate-induced changes in nidus mineralisation and regional bone-marrow oedema (BMO). METHODS: A prospective, observational study was conducted from 2011 to 2014. Patients with risk factors for complications of percutaneous or surgical ablation or recurrence after ablation, were offered once monthly intravenous bisphosphonate treatment until significant pain alleviation was achieved. RESULTS: We included 23 patients. The first two patients received pamidronate and the next 21 zoledronic acid (mean, 2.95 infusions per patient). Bisphosphonate therapy was successful in 19 patients (83%), whose mean pain visual analogue scale score decreased by 76.7%; this pain-relieving effect persisted in 17 patients (74%) with a mean follow-up time of 36 months. Computed tomography (CT) demonstrated a mean nidus density increase of 177.7% (p = 0.001). By magnetic resonance imaging (MRI), mean decreases were 38.4% for BMO surface area and 30.3% for signal intensity (p = 0.001 and p = 0.000, respectively). CONCLUSIONS: In 17/23 patients with painful OO managed conservatively with bisphosphonates, long-term final success was achieved. Bisphosphonates may accelerate the spontaneous healing of OO. KEY POINTS: • 19/23 patients with OO managed with bisphosphonates experienced significant pain relief • Pain relief was sustained in 17/23 patients, mean follow-up of 36 months • CT demonstrated a significant increase in nidus mineralisation • MRI demonstrated a significant decrease in bone marrow oedema • Bisphosphonate therapy may accelerate the spontaneous healing of OO.

Percutaneous low-pressure bone stenting to control cement deposition in extensive lytic lesions.

OBJECTIVE: To evaluate low-pressure bone stenting combined with cementoplasty in extensive lytic lesions. METHODS: A single-centre study involving four consecutive patients (four women) with extensive lytic tumours was performed. The average age was 65 years. Surgical treatment was not indicated or not wished for by the patients. Institutional review board approval and informed consent were obtained. Percutaneous consolidation was performed by an interventional radiologist under fluoroscopy guidance. Follow-up was assessed using the visual analogue scale (VAS). RESULTS: Under general (n = 2) or local (n = 2) anaesthesia, five 11-gauge bone biopsy needles were advanced in four lesions. Five auto-expandable uncovered stents (10-14 mm diameter and 40-60 mm long) were inserted. In all cases, bone cement was successfully placed into the tumours. The volume of cement that was injected through the cannulas into the stents was 5-10 mL. Using VAS, pain decreased from more than 9/10 preoperatively to less than 2/10 after the procedure for all patients (p < 0.05). No complications occurred during the follow-up (8-19 months). CONCLUSION: This study suggests that cementoplasty combined with low-pressure bone stenting could allow effective bone stabilization resulting in pain relief. KEY POINTS: • Low-pressure bone stenting is possible. • This technique improves cement injection control. • The procedure allows effective bone stabilization resulting in pain relief.

Patient-specific 3D models created by 3D imaging system or bi-planar imaging coupled with Moiré-Fringe projections: a comparative study of accuracy and reliability on spinal curvatures and vertebral rotation data.

PURPOSE: The aim of this study is to compare the accuracy and reliability of spinal curvatures and vertebral rotation data based on patient-specific 3D models created by 3D imaging system or by bi-planar imaging coupled with Moiré-Fringe projections. METHODS AND MATERIALS: Sixty-two consecutive patients from a single institution were prospectively included. For each patient, frontal and sagittal calibrated low-dose bi-planar X-rays were performed and coupled simultaneously with an optical Moiré back surface-based technology. The 3D reconstructions of spine and pelvis were performed independently by one radiologist and one technician in radiology using two different semi-automatic methods using 3D radio-imaging system (method 1) or bi-planar imaging coupled with Moiré projections (method 2). Both methods were compared using Bland-Altman analysis, and reliability using intraclass correlation coefficient (ICC). RESULTS: ICC showed good to very good agreement. Between the two techniques, the maximum 95 % prediction limits was -4.9° degrees for the measurements of spinal coronal curves and less than 5° for other parameters. Inter-rater reliability was excellent for all parameters across both methods, except for axial rotation with method 2 for which ICC was fair. Method 1 was faster for reconstruction time than method 2 for both readers (13.4 vs. 20.7 min and 10.6 vs. 13.9 min; p = 0.0001). CONCLUSION: While a lower accuracy was observed for the evaluation of the axial rotation, bi-planar imaging coupled with Moiré-Fringe projections may be an accurate and reliable tool to perform 3D reconstructions of the spine and pelvis.

Stabilisation of a loosened femoral gamma nail by percutaneous cement injection (cementoplasty): a new technique.

Surgical repair of pertrochanteric and subtrochanteric fractures in the elderly is usually achieved using an endomedullary nail. Unfortunately, even today, some of the patients who undergo this intervention develop periprosthetic bone absorption over time that can lead to loosening of the prosthesis, resulting in pain, joint instability and the need for revision surgery. Surgical revision is hindered by potential complications related to patients' existing underlying medical conditions. It is often the case that these patients are weak and present comorbidities, which can lead to an absolute contraindication to surgery. An interesting alternative could be the stabilisation by percutaneous injection of cement (cementoplasty) in the periprosthetic space under CT and fluoroscopic guidance. In patients with absolute contraindication we performed percutaneous cementoplasty as treatment for femoral prosthesis loosening. Our procedure was technically a success following the end of the intervention period (follow-up: 6 months). The patient no longer experienced significant pain and showed stability of the prosthesis, as demonstrated by CT.

Musculoskeletal injuries in a resource-constrained environment: comparing diagnostic accuracy of on-the-spot ultrasonography and conventional radiography for bone fracture screening during the Paris-Dakar rally raid.

BACKGROUND: Ultrasound (US) is a good first-line alternative for the diagnosis of bone fractures in adults as well as children. Our study shows that, compared to X-ray, in a resource-constrained environment, on-site US has a high sensitivity (98%) and specificity (96%) in the diagnosis of bone fractures. PURPOSE: To compare the accuracy of on-the-spot US with conventional radiography in the screening for bone fractures during the Paris-Dakar rally raid. MATERIAL AND METHODS: Eighty-three patients (81 men, 2 women) with clinically suspected bone fractures were included in 2013 and 2014. They underwent X-ray and US on the spot, blindly interpreted by two musculoskeletal radiologists. Using X-ray as gold standard, we calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for US, for each anatomic location. The accuracy of US and radiography were also assessed, as were the number of fragments and their degree of displacement (Student's t-test). RESULTS: Compared with X-ray, sensitivity, specificity, PPV, and NPV of on-site US were, respectively, for the presence (or absence) of fractures: 98%, 98%, 100%, and 95%. The accuracy of US was 99%. Only one radial styloid process fracture was misdiagnosed with US. There was no significant difference between US and X-ray (P > 0.93) concerning the number of fragments and their degree of displacement. CONCLUSION: Bedside musculoskeletal ultrasound performed by trained musculoskeletal radiologists is a useful method in determining and assessing bone fractures in a resource constrained environment.

Percutaneous consolidation of loosened spine arthrodesis under CT and fluoroscopy guidance by radiologists: a new useful technique.

OBJECTIVE: The objective was to evaluate percutaneous computed tomography (CT) and fluoroscopy-guided injection of bone cement for consolidation of loosened posterior arthrodesis performed by radiologists. METHODS: A single-centre prospective study involving four consecutive patients (three women, one man) suffering from screw loosening (three at the vertebral level, one at the iliac wing level) after Posterior Lumbar Interbody Fusion (PLIF) treatment was done. The average age was 80 years. Surgical treatment was not indicated or not wished for by the patients. Institutional review board approval and informed consent were obtained. Percutaneous consolidation was performed by an interventional radiologist under CT and fluoroscopy guidance. The path of the trocars was made outside loosened screws bilaterally. Follow-up was assessed using the Visual Analog Scale (VAS). RESULTS: In all cases, bone cement was successfully placed around the loosened screw. The mean volume of cement that was injected was 3 ml. No cement leakage was observed. No neurological complication occurred. Using VAS, pain decreased from more than 9/10 preoperatively to less than 2/10 the day after the procedure for all patients (p < 0.05). CONCLUSION: This study suggests that loosening of spine arthrodesis could be successfully treated by percutaneous injection of bone cement under CT and fluoroscopy guidance. KEY POINTS: • PLIF is one of the surgical techniques for spinal arthrodesis. • Treatment indications are degenerative disease or instability following trauma, tumour, or infection. • Screw loosening is a frequent complication that can occur after surgery. • Percutaneous facet consolidation under dual guidance seems to be a feasible technique. • The procedure is performed under local anaesthesia using a minimally invasive approach.

US in ankle impingement syndrome.

Ankle impingement is a common condition occurring secondary to sprain or repeated microtrauma. Clinical symptoms are chronic pain located in the affected region and limited range of ankle motion. There are three types of ankle impingement syndrome: anterior impingement, which can be subdivided into anterolateral, anteromedial and purely anterior impingement; posterior impingement, which can be subdivided into posterior and posteromedial impingement; and calcaneal peroneal impingement which is secondary to planovalgus foot deformity. This paper evaluates physiological and clinical elements of these three types of ankle impingement syndrome as well as the role of ultrasound (US) imaging and US-guided treatment.

I conflitti di caviglia sono comuni, a seguito di distorsioni o di microtraumi ripetitivi, i sintomi clinici associati sono dolore cronico dalla topografia variabile e limitazione, più o meno dolorosa, dei movimenti. Complessivamente esistono tre tipi di conflitti: anteriori che possono essere suddivisi in antero-laterali, antero-mediali e anteriori puri, posteriori che possono essere divisi in posteriori e postero-mediali e calcaneo-peroneale, secondario al piede piatto valgo. Dei vari tipi di conflitto vengono valutati la fisiologia, la clinica, l'imaging ed il ruolo dell'ecografia. Viene infine considerata la possibilità di trattamenti terapeutici eco-guidati.

Vertebral split fractures: technical feasibility of percutaneous vertebroplasty.

OBJECTIVE: The treatment of vertebral split fractures remains controversial, consisting of either corset or internal fixation. The aim of this study was to evaluate the technical feasibility of CT- and fluoroscopy-guided percutaneous vertebroplasty in the treatment of vertebral split fractures. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained for this study. Sixty-two consecutive adult patients who had post-traumatic vertebral split fractures (A2 according to the AO classification) without neurological symptoms were prospectively treated by percutaneous vertebroplasty. All these procedures were performed by an interventional radiologist under computed tomography (CT) and fluoroscopy guidance by using only local anaesthesia. Postoperative outcome was assessed using the visual analogue scale (VAS) and Oswestry disability index (ODI) scores. RESULTS: Vertebroplasty was performed on thoracic and lumbar vertebrae, creating a cement bridge between the displaced fragment and the rest of the vertebral body. Seven discal cement leakages (11%) were observed, without occurrence of adjacent vertebral compression fractures. The mean VAS measurements ± standard deviation (SD) significantly decreased from 7.9 ± 1.5 preoperatively to 3.3 ± 2.1 at 1 day, 2.2 ± 2.0 at 1 month, and 1.8 ± 1.4 at 6 months (P<0.001). The mean ODI scores ± SD had also a significant improvement: 62.3 ± 17.2 preoperatively and 15.1 ± 6.0 at the 6-month follow-up (P<0.001). CONCLUSION: This study suggests that type A2 vertebral fractures could be successfully treated by CT- and fluoroscopy-guided percutaneous vertebroplasty.

[Imaging of bone metastases]. / Sémiologie des métastases osseuses en radiologie conventionnelle.

Bone metastases are detected at initial diagnosis of cancer in 25% of cases and bone metastases are common in the course of a majority of cancer types. The spine and proximal long bones are the most affected sites. Knowledge of the basic radiological semiology is important to make the proper diagnosis of metastasis(s) bone(s), especially in situations in which the clinical context is not suggestive of metastases (such as cases where bone metastases are inaugural or cases of peripheral solitary metastasis). Tumor aggressiveness can be assessed at the level of the cortical bone and periosteum. Lodwick criteria are useful for the diagnosis of malignancy and tumor aggressiveness at initial diagnosis on plain radiographs, which are very important in the context of bone metastases. A CT scanner is required to confirm the malignancy of a bone lesion. MRI is complementary to the scanner including for the assessment of bone marrow involvement and tumor extensions.

Percutaneous facet screw fixation of lumbar spine with CT and fluoroscopic guidance: a feasibility study.

PURPOSE: To assess the feasibility of computed tomography (CT)- and fluoroscopy-guided percutaneous facet screw fixation following anterior lumbar interbody fusion (ALIF) or anterior pseudarthrosis in adults. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained for this study. One hundred seven consecutive adult patients (46 men, 61 women; mean age ± standard deviation: 56.3 years ± 12.9) with ALIF (n = 79) or anterior pseudarthrosis (n = 28) were prospectively treated by means of percutaneous facet screw fixation with CT and fluoroscopic guidance. Two 4.0-mm cannulated screws were placed per level to fix facet joints by using either a translaminar facet or transfacet pedicle pathway. Only local anesthesia was used during these procedures. Procedural time was noted for each patient. Postoperative follow-up ranging from 1 year to 3 years was assessed by using Macnab and radiologic criteria. RESULTS: The mean procedure times for a lumbar single-level and a double-level fusion ranged from 15 to 25 minutes and from 40 to 50 minutes, respectively. All the transfacet pedicle (n = 182) and translaminar facet (n = 56) screws were successfully placed in one attempt. Radiographic fusion was observed within the year following posterior fixation in all patients despite one translaminar screw failure. According to the Macnab criteria, the clinical results were classified as excellent in 92 (86%) and good in 15 (14%) of 107 patients at the time of their last follow-up examination. CONCLUSION: This feasibility study showed that CT- and fluoroscopy-guided percutaneous facet screw fixation is a rapid, safe, and effective method.

Percutaneous screw fixation of acetabular roof fractures by radiologists under CT and fluoroscopy guidance.

OBJECTIVE: The aim of this study was to evaluate CT- and fluoroscopy-guided percutaneous screw fixation by radiologists in the management of acetabular roof fractures. SUBJECTS AND METHODS: Fifty-two consecutive adult patients with a nondisplaced and isolated acetabular roof fracture were prospectively treated by an interventional radiologist who made a percutaneous screw fixation under CT and fluoroscopy guidance. All these procedures were performed under local anesthesia. The postoperative follow-up ranged from 36 to 48 months. RESULTS: For each patient, two 6.5-mm Asnis III screws were inserted to fix the roof acetabular fracture. The mean procedure time was 45 minutes (range, 30-90 minutes). No complications were observed. Follow-up CT showed evidence of fracture healing. No evidence of secondary displacement, degenerative changes, or screw failure was noted. Using the rating system of D'Aubigne and Postel, all patients had excellent results. CONCLUSION: The results of our study showed that nondisplaced acetabular roof fractures could be successfully treated by a minimally invasive technique with an excellent long-term outcome.

CT- and fluoroscopy-guided percutaneous discectomy for lumbar radiculopathy related to disc herniation: a comparative prospective study comparing lateral to medial herniated discs.

OBJECTIVE: To evaluate and compare two groups of patients with sciatica due to intervertebral disc herniation with no neurologic deficit. The groups consisted of patients with intervertebral disc herniation in a medial location (group 1) and those in a lateral location (group 2). MATERIALS AND METHODS: A total of 200 patients were included in the study and were followed for a minimum of 6 months. In our series, we treated 80 postero-lateral herniated discs (40% of cases), 46 postero-medial herniated discs (23%), and 74 foraminal herniated discs (37%). Level L3-L4 was treated in 30 cases (15%), L4-L5 in 98 cases (49%), and L5-S1 in 72 cases (36%). The procedure was performed under dual guidance: fluoroscopic and CT. A helical probe was activated. It penetrates the herniated disc and causes the pulpous material to be mechanically evacuated through the probe. All 200 patients were followed for a minimum of 6 months. RESULTS: In group 1, the patients had a mean pain score of 7.9 ± 2.5 VAS units (range 6-10 units) prior to intervention. This was reduced to 3.2 ± 2.1 VAS units (range 0-10 units) at 48 h follow-up and increased to 3.9 ± 1.2 VAS units (range 0-10 VAS units) at 1 month follow-up and further reduced to 2.7 ± 1.2 units (range 0-10 VAS units) at 6 month follow-up. In group 2, the patients had a mean pain score of 8.2 ± 3.2 VAS units (range 6-10 units) prior to intervention. This was reduced to 2.8 ± 1.5 VAS units (range 0-10 units) at 48 h follow-up and decreased to 1.5 ± 0.9 VAS units (range 0-10 units) at 1 month and further reduced to 1.1 ± 0.5 VAS units (range 0-10 units) at 6 months. CONCLUSION: Our study showed that results were more satisfactory for the hernia located laterally (postero-lateral, foraminal, and extra-foraminal) as compared to the hernia located posteromedially.