Pedicle Screw Track Augmentation With Fibular Allograft for Significant Bone Loss in Revision Fixation.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To report the clinical and radiological outcomes for screw track augmentation with fibular allograft in revision of loose pedicle screws associated with significant bone loss along the screw track. METHODS: Thirty consecutive patients, 18 men (60%) and 12 women (40%), with a mean age 52 years (range 34- 68). Fibular allograft was prepared by cutting it into longitudinal strips 50 mm in length. Three allograft struts were inserted into the screw track. Six mm tap used to tap between the 3 fibular struts. Eight- or 9-mm diameter, and 45 or 50 mm in length screw was then inserted. The clinical outcomes were assessed by means of the Oswestry Disability Index (ODI), and visual analog scale (VAS) for back and leg pain for clinical outcome. Computed tomography scan (CT) performed at 12 months postoperative visit to assess fibular graft incorporation along the pedicle screw track, any screw loosening and the interbody as well as posterolateral fusion. RESULTS: At a mean follow up of 29 months, there were statically significant improvement in the ODI and VAS for back and leg pain. CT scan obtained at last follow-up showed incorporation of fibular allograft and solid fusion in all patients except one. CONCLUSION: The fibular allograft augmentation of the pedicle screw track in revision of loose pedicle screws associated with significant bone loss is a viable option. It allows for biologic fixation at the screw-bone interface and has some key advantages when compared to currently available methods.

Lumbar spine fusion outcomes using a cellular bone allograft with lineage-committed bone-forming cells in 96 patients.

BACKGROUND: Instrumented posterior lumbar fusion (IPLF) with and without transforaminal interbody fusion (TLIF) is a common treatment for low back pain when conservative interventions have failed. Certain patient comorbidities and lifestyle risk factors, such as obesity and smoking, are known to negatively affect these procedures. An advanced cellular bone allograft (CBA) with viable osteogenic cells (V-CBA) has demonstrated high fusion rates, but the rates for patients with severe and/or multiple comorbidities remain understudied. The purpose of this study was to assess fusion outcomes in patients undergoing IPLF/TLIF using V-CBA with baseline comorbidities and lifestyle risk factors known to negatively affect bone fusion. METHODS: This was a retrospective study of de-identified data from consecutive patients at an academic medical center who underwent IPLF procedures with or without TLIF, and with V-CBA. Baseline patient and procedure characteristics were assessed. Radiological outcomes included fusion rates per the Lenke scale. Patient-reported clinical outcomes were evaluated via the Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) for back and leg pain. Operating room (OR) times and intraoperative blood loss rates were also assessed. RESULTS: Data from 96 patients were assessed with a total of 222 levels treated overall (mean: 2.3 levels) and a median follow-up time of 16 months (range: 6 to 45 months). Successful fusion (Lenke A or B) was reported for 88 of 96 patients (91.7%) overall, including in all IPLF-only patients. Of 22 patients with diabetes in the IPLF+TLIF group, fusion was reported in 20 patients (90.9%). In IPLF+TLIF patients currently using tobacco (n = 19), fusion was reported in 16 patients (84.3%), while in those with a history of tobacco use (n = 53), fusion was observed in 48 patients (90.6%). Successful fusion was reported in all 6 patients overall with previous pseudarthrosis at the same level. Mean postoperative ODI and VAS scores were significantly reduced versus preoperative ratings. CONCLUSION: The results of this study suggest that V-CBA consistently yields successful fusion and significant decreases in patient-reported ODI and VAS, despite patient comorbidities and lifestyle risk factors that are known to negatively affect such bony healing.

Overreporting of the disc herniation in lumbar spine MRI scans performed for patients with spondylolisthesis.

BACKGROUND: Spondylolisthesis is often misdiagnosed on magnetic resonance imaging (MRI) as the slip may reduce to a normal alignment when the patient lies supine. Often, disc herniation is reported at the level of spondylolisthesis. PURPOSE: To determine the incidence rates of disc herniation at the level of spondylolisthesis. MATERIAL AND METHODS: This is a retrospective study included 258 consecutive patients with spondylolisthesis who had lumbar spine MRI. The archived reports were collectively put in Group 1. A musculoskeletal radiologist and a spine surgeon reviewed the imaging studies together. Their readings were referred to as Group 2. The findings of both groups were compared to evaluate whether disc herniation was overreported. RESULTS: Group 1 reported findings of true disc herniation in 112 (41.6%) cases and pseudo disc herniation or no findings of disc herniation at the level of spondylolisthesis in 157 (58.4%) cases. Group 2 reported findings of a true disc herniation in 25 (9.3%) cases and pseudo disc herniation or no findings of disc herniation in the remaining 244 (90.7%) cases. There was a statistically significant difference in the reporting rates between these two groups (P < 0.02). The most overreported finding was the disc bulging (P < 0.01). CONCLUSION: The current study showed overreporting of disc herniation in lumbar spine MRI scans performed for patients with established spondylolisthesis. The majority of disc pathology at the level of spondylolisthesis are pseudo disc rather than a true disc herniation. An accurate diagnosis is vital in planning surgical intervention.

Diagnosing cystic duct patency during myocardial perfusion imaging (MPI), using Tc99m Sestamibi (MIBI), as an adjunct benefit in the acute setting.

OBJECTIVE: Tc99m methoxy isobutyl isonitrile (MIBI) has been used for myocardial perfusion imaging (MPI) for the detection of ischemia. This study aimed to investigate the feasibility of effectively evaluating cystic duct patency, during routine visual analysis of the raw MPI and/or with the three-dimensional reconstructed data. METHODS: A retrospective investigation of 91 patients undergoing cardiac MIBI scan for acute chest pain and hepatobiliary scintigraphy (HBS) was performed, within no more than 3 months for suspected gallbladder obstructive disease. Gallbladder visualization during either the stress or rest portion of the MIBI was indicative of cystic duct patency. These results were compared to those by the HBS studies. RESULTS: Ten patients had the MIBI and HBS 4 days apart, both analyses concurred 100% with the diagnosis of cystic duct patency. 16 patients had both examinations between 4 days and 3 weeks and had an agreement of 87.5% with cystic duct patency. 65 patients had both tests 3 weeks to 3 months apart and had an agreement of 84.6% with cystic duct patency. CONCLUSION: The initial results of this study indicate that MPI with Tc99m MIBI is useful in detecting a patent cystic duct, above all in the setting of acute gallbladder pathology. ADVANCES IN KNOWLEDGE: In this article, we introduce a novel method to diagnose cystic duct patency in the acute setting thus effectively ruling out acute cholecystitis, during MPI. Our method can potentially improve patient outcomes by reducing the volume of imaging needed to exclude a diagnosis of acute gallbladder pathology. This in turn, keeps in line with decreasing the cost for the patient, leading to a more sound value-based care.

Diagnostic accuracy of non-contrast abdominal CT scans performed as follow-up for patients with an established cancer diagnosis: a retrospective study.

OBJECTIVES: To determine the accuracy and non-detection rate of cancer related findings (CRFs) on follow-up non-contrast-enhanced CT (NECT) versus contrast-enhanced CT (CECT) images of the abdomen in patients with a known cancer diagnosis. METHODS: A retrospective review of 352 consecutive CTs of the abdomen performed with and without IV contrast between March 2010 and October 2014 for follow-up of cancer was included. Two radiologists independently assessed the NECT portions of the studies. The reader was provided the primary cancer diagnosis and access to the most recent prior NECT study. The accuracy and non-detection rates were determined by comparing our results to the archived reports as a gold standard. RESULTS: A total of 383 CRFs were found in the archived reports of the 352 abdominal CTs. The average non-detection rate for the NECTs compared to the CECTs was 3.0% (11.5/383) with an accuracy of 97.0% (371.5/383) in identifying CRFs. The most common findings missed were vascular thrombosis with a non-detection rate of 100%. The accuracy for non-vascular CRFs was 99.1%. CONCLUSION: Follow-up NECT abdomen studies are highly accurate in the detection of CRFs in patients with an established cancer diagnosis, except in cases where vascular involvement is suspected.

Clinical outcome and subsequent sequelae of cement extravasation after percutaneous kyphoplasty and vertebroplasty: a comparative review.

Background Injection of cement during vertebroplasty and kyphoplasty can leak into surrounding structures and could be symptomatic. Purpose To identify the sites and incidence of cement extravasation after kyphoplasty and vertebroplasty, and to evaluate their impacts on clinical outcomes. Material and Methods A retrospective review of 316 patients treated with kyphoplasty and vertebroplasty; 411 cases were included (223 kyphoplasty and 188 vertebroplasty). Cement extravasation was evaluated postoperatively by computed tomography (CT) scan of the spine. Clinical outcomes were assessed by visual analog scale (VAS) and Oswestry Disability Index (ODI). Results There was a statistically significant difference in the incidence rate of cement extravasation between vertebroplasty and kyphoplasty groups ( P < 0.04). The most common site of cement extravasation was in paravertebral soft tissues for vertebroplasty (n = 33, 40.7%) and for kyphoplasty (n = 30, 30%). In the subgroup where cement leaked into the intradiscal space, adjacent vertebral body fractures occurred in 3/26 vertebrae (11.5%) in the vertebroplasty group and in 2/18 vertebrae (11.1%) in the kyphoplasty group. Both groups showed a statistically significant decrease in both VAS ( P < 0.001) and ODI scores ( P < 0.001). There was no significantly difference in patient satisfaction between those who had cement extravasation and those who did not, in both groups. Conclusion Kyphoplasty has an advantage in terms of less risk of cement extravasation. However, this factor did not reflect on subsequent sequelae or final clinical outcomes. This study did not find a distinct correlation between intradiscal cement extravasation and increased risk of adjacent vertebral fractures.

Incidental Extraspinal Findings at Lumbar Spine Magnetic Resonance Imaging: A Retrospective Study.

STUDY DESIGN: Retrospective study of a consecutive series of patients undergoing lumbar spine magnetic resonance imaging (MRI) for low back pain at a single institution. OBJECTIVE: To determine the prevalence and nondetection rate of incidental extraspinal findings (IESFs) in adult patients undergoing MRI of the lumbar spine performed for low back pain by using a structured approach. SUMMARY OF BACKGROUND DATA: Extraspinal findings are depicted on lumbar spine magnetic resonance image. There is limited evidence concerning their prevalence, importance, how often they are missed by interpreting physician, and how to improve their detection. METHODS: Our study was approved by our institutional review board committee, which waived informed consent because it was retrospective. Lumbar spine magnetic resonance images obtained for low back pain at our institution from January 2011 to December 2013 were assessed by 3 readers for IESFs using a structured approach and their results compared with the archived reports. Repeat lumbar spine MRI and cases with a history of trauma were excluded. A total of 3024 lumbar spine magnetic resonance images were included. IESFs were classified according to the organ involved and to the model adopted by the modified CT Colonography Reporting and Data System (C-RADS). Nondetection rates were determined by comparing the results of our structured approach with the archived MRI reports. RESULTS: A total of 859 IESFs were found in 671 of 3024 lumbar spine patients undergoing MRI (22%). A total of 623 out of them (73%) were categorized E2 (clinically unimportant finding), 192 (22%) were categorized E3 (likely unimportant finding), and 44 (5%) were categorized E4 (potentially important finding). A total of 347 of 859 findings were not mentioned in the archived reports for a nondetection rate of 40%. The nondetection rate for E4 category findings was 38.6% (17/44). CONCLUSION: IESFs on lumbar spine MRI are common with a significant nondetection rate of 40% using a nonstructured approach. Specifically, there was a significant nondetection rate of 38.6% for potentially important (E4) findings. LEVEL OF EVIDENCE: 3.

Effectiveness and safety of transforaminal lumbar interbody fusion in patients with previous laminectomy.

PURPOSE: To determine the efficacy and safety of transforaminal lumbar interbody fusion (TLIF) for revision lumbar spine surgery in patients with previous laminectomy. The secondary objective was to evaluate the clinical and radiological outcome after such a procedure. METHODS: Retrospective case series study. Eighty-two patients were included. There were 48 women (58.5 %) and 34 men (41.5 %) with a mean age of 51 years (range 26-84) at the time of index procedure. The outpatient and inpatient charts were reviewed to identify patients' demographic data, preoperative, perioperative, and postoperative data. The outcome measures were assessed by Oswestry Disability Index (ODI) and visual analog scale (VAS) for back and leg pain. An independent spine surgeon and musculoskeletal radiologist reviewed the imaging studies. RESULTS: The average operative time was 160 min (range 131-250). The average estimated blood loss was 652 cc (100-1,400 cc). Nineteen patients (23.1 %) required blood transfusion. Five patients (6 %) had dural tear. One patient (1.2 %) had a surgical site infection. Two patients (2.4 %) had thromboembolic events. The average hospital stay was 3.8 days (2-5 days). At a mean follow-up of 28 months, there were statically significant improvement in the ODI and VAS for back and leg pain. None of the patients' radiographs showed hardware failure or pedicle screw loosening and no patient returned to the operating room for pseudarthrosis. CONCLUSIONS: The current study confirmed that TLIF approach in patients with previous laminectomy is effective and safe with good outcomes.

Clinical and radiographic evaluation of sagittal imbalance: a new radiographic assessment.

In this article, we describe a case series study involving a new radiologic evaluation of sagittal imbalance. We review the current radiologic assessment of sagittal imbalance and introduce a new radiologic evaluation that helps in ruling out hip flexion contracture as the primary cause of sagittal imbalance and the type and level of spinal osteotomy required to regain sagittal balance. Sagittal imbalance is important in spinal deformity assessment. Studies have confirmed that overall clinical outcomes and patient satisfaction with surgery were best in cases that resulted in an increase in lumbar lordosis. For this study, radiologic assessment of sagittal imbalance was conducted on a long, 14 × 51-inch upright lateral plain radiograph that included the proximal femur and the entire spine. The radiograph was taken with the arms at 45° forward flexion and the hips and knees fully extended. The femoral axis line was drawn and extended cephalad. The C7 offset, the perpendicular distance between the femoral axis line and the center of C7, represented the degree of sagittal imbalance. The angle between the femoral axis line and a line extending from the center of C7 to the vertebra at the level of the proposed osteotomy--the Seattle angle--predicted how much correction was required to bring the C7 plumb in line with the femoral axis and to decrease the C7 offset, thus regaining sagittal balance. The proposed method was used to evaluate 10 consecutive patients who required spinal osteotomies to regain sagittal balance. Preoperative and postoperative plain radiographs were assessed twice, at a 6-week interval, by an independent spine surgeon and a musculoskeletal radiologist. Cohen κ correlation coefficients were used to calculate intraobserver and interobserver reliability. The 2 reviewers' intraobserver reliability was excellent (κs = 0.98, 0.93). Interobserver reliability was lower but good (κ = 0.76). Inclusion of the proximal femur on the long upright lateral plain radiograph of the entire spine and identification of the relation between the femoral axis line and the center of C7 are important in evaluating sagittal imbalance. Excellent intraobserver reliability, coupled with good interobserver reliability, suggest that this new radiologic assessment method can be helpful in preoperative assessment of sagittal imbalance.

Computed tomography of normal distal tibiofibular syndesmosis.

OBJECTIVE: The purpose of this study was to determine the shape and measurements of the normal distal tibiofibular syndesmosis on computed tomographic scans and to identify features that could aid in the diagnosis of syndesmotic diastasis using computed tomography (CT). MATERIALS AND METHODS: CT scans of 100 patients with normal distal tibiofibular syndesmoses were reviewed retrospectively. In 67% the incisura fibularis was deep, giving the syndesmosis a crescent shape. In 33% the incisura fibularis was shallow, giving the syndesmosis a rectangular shape. The measurements of both types were taken using the same reference points. RESULTS: The mean age of the patients was 40 years, and there were 53 men and 47 women. The mean width of the distal tibiofibular syndesmosis anteriorly between the tip of the anterior tibial tubercle and the nearest point of the fibula was 2 mm. The mean width of the distal tibiofibular syndesmosis posteriorly between the medial border of the fibula and the nearest point of the lateral border of the posterior tibial tubercle was 4 mm. In men the mean width of the distal tibiofibular syndesmosis, anterior and posterior, was 2 mm and 5 mm, respectively, and in women it was 2 mm and 4 mm, respectively. CONCLUSION: This study provides measurements of the normal tibiofibular syndesmosis to aid in the diagnosis of occult diastasis.

[Radiologic appearance of non-traumatic intracranial hemorrhage]. / Le radiologiste face à une hémorragie intracrânienne non traumatique.

The diagnosis of nontraumatic intracranial hemorrhage is currently made by computed tomography and is rarely problematic. The causes of bleeding are very numerous. It is important to determine the cause of the hemorrhage promptly, because there may be a recurrence of bleeding. Guidelines for radiologists are proposed and discussed here.

Factors affecting the hepatobiliary excretion of 99mTc-MAG3: its clinical significance in routine renography.

OBJECTIVE: Since the approval of mercaptoacetyltriglycine (MAG3) for routine clinical use, reports have appeared about hepatobiliary excretion deleteriously affecting available diagnostic and quantitative information. The purpose of this study was to evaluate gallbladder (GB) uptake of MAG3 in the clinical setting and its effect on the evaluation of relative renal function and imaging. METHODS: Sixty patients with varying degrees of renal impairment were studied. Routine renal function imaging was followed with anterior and right lateral 3-min abdominal images. Factors such as photolytic degradation, reconstitution steps, (99m)Tc O(4) solution, age, and concentration are discussed. In addition, patient fasting state and radiochemical purity are evaluated. The GB uptake was determined as a percentage of the injected dose. RESULTS: The MAG3 quality control ranged from 90.9% to 99.0%. The GB uptake ranged from 0.0% (not visualized) to 0.71%. The effective renal plasma flow ranged from 88 to 743 mL/min. There was no correlation between the QC and the percentage of GB uptake (r = 0.12). The majority of patients in the nonfasting state showed minimal or reduced GB uptake when compared with the majority of patients in the fasting state. CONCLUSION: Our data suggest that GB uptake of MAG3 is minimal, with no adverse effects on the diagnostic and quantitative analysis of renal function.