Charles Gerald T. Ledonio

Pediatric Pedicle Screw Placement Using Intraoperative Computed Tomography and 3-Dimensional Image-Guided Navigation

Study Design. A retrospective cohort study reporting the use of intraoperative computed tomography (CT) and image-guided navigation system for the placement of pedicle screws in pediatric compared with adult patients. Objective. To evaluate the accuracy of open pedicle screw placement in pediatric patients using intraoperative CT and 3-dimensional (3D) image-guided navigation. Summary of Background Data. Pedicle screws are widely used in children for the correction of spinal deformity. Navigation systems and intraoperative CT are now available as an adjunct to fluoroscopy and anatomic techniques for placing pedicle screws and verifying screw position. Methods. From 2007 to 2010, 984 pedicle screws were placed in a consecutive series cohort of 50 pediatric patients for spinal deformity correction with the use of intraoperative CT (O-arm, Medtronic, Inc, Louisville, CO) and a computerized navigation system (Stealth, Medtronic, Inc, Louisville, CO). The primary outcome measure for this study is redirection or removal of screw on the basis of the intraoperative CT imaging. During the study period, 1511 screws were placed in adult patients using the same image guidance system. Results. A total of 984 pedicle screws were implanted using real-time navigation, with a mean of 20 screws per patient (range: 2–34). On the basis of intraoperative CT, 35 screws (3.6%) were revised (27 redirected and 8 removed), representing a 96.4% accuracy rate. No patients returned to the operating room because of screw malposition. Of the 1511 screws placed in adult patients, 28 (1.8%) were revised intraoperatively for malposition on CT imaging, for an overall 98.2% accuracy rate. Screw revision thus was more common in the pediatric population (P = 0.008). However, the pediatric screw accuracy rate is significantly higher than the findings from a recent meta-analysis of predominantly nonnavigated screws in children, reporting a 94.9% accuracy rate (P = 0.03). Conclusion. We report 96.4% accuracy in pediatric pedicle screw placement using intraoperative CT and a 3D navigation system. This is similar to other reports and has better accuracy than a recent meta-analysis of nonnavigated screws in children.

Pediatric pedicle screws: Comparative effectiveness and safety - A systematic literature review from the Scoliosis Research Society and the Pediatric Orthopaedic Society of North America task force

BACKGROUND Pedicle screws are widely used in spinal surgery. There is extensive published literature concerning the use of pedicle screw instrumentation for spinal surgery in adults. Now there is a trend to use pedicle screws in pediatric patients, including the very young. A systematic review of the current English-language literature on the use of pedicle screw instrumentation in the pediatric age group was performed to specifically determine (1) the pedicle screw placement accuracy in patients with spine deformity and (2) the effect size of all-pedicle screw constructs compared with other methods of spinal instrumentation in terms of the percentage of scoliosis correction. METHODS English-language studies of pedicle screw use in pediatric patients (defined as those younger than eighteen years of age) were included. Descriptive statistics synthesized the accuracy of pedicle screw placement. Accuracy rates were compared between pediatric and adult patients. The effect of pedicle screw instrumentation on scoliosis correction was calculated with use of Cobb angle measurements. RESULTS On the basis of the literature search, 1181 articles were screened, 320 abstracts were examined, and ninety full-text articles representing 5761 patients were reviewed in detail. Seventeen studies met the inclusion criteria for the analysis of pedicle screw placement accuracy. A total of 13,536 pedicle screws were placed in 1353 pediatric patients. The overall placement accuracy rate in pediatric patients was 94.9%, which was higher than the rate of 91.5% reported for adults. The weighted, geometric, and 5% trimmed mean accuracy rates of pedicle screw placement were 91.9%, 88.5%, and 89.1%, respectively (standard deviation = 10%; interquartile range = 10%). Sixteen comparative studies met the inclusion criteria for the analysis of the effect of pedicle screw instrumentation on scoliosis correction. Pedicle screw constructs had a significantly larger percentage of Cobb angle correction compared with hooks (Cohens d = 1.14) and hybrid constructs (Cohens d = 0.49). CONCLUSIONS The accuracy of pedicle screw placement in the pediatric spine exceeds the accuracy rate reported in adults. Pedicle screw instrumentation constructs are significantly more effective for scoliosis correction, as determined on the basis of Cobb angle measurements, than are hook constructs and hybrid constructs.

Pediatric pedicle screws

BACKGROUND Pedicle screws are widely used in spinal surgery. There is extensive published literature concerning the use of pedicle screw instrumentation for spinal surgery in adults. Now there is a trend to use pedicle screws in pediatric patients, including the very young. A systematic review of the current English-language literature on the use of pedicle screw instrumentation in the pediatric age group was performed to specifically determine (1) the pedicle screw placement accuracy in patients with spine deformity and (2) the effect size of all-pedicle screw constructs compared with other methods of spinal instrumentation in terms of the percentage of scoliosis correction. METHODS English-language studies of pedicle screw use in pediatric patients (defined as those younger than eighteen years of age) were included. Descriptive statistics synthesized the accuracy of pedicle screw placement. Accuracy rates were compared between pediatric and adult patients. The effect of pedicle screw instrumentation on scoliosis correction was calculated with use of Cobb angle measurements. RESULTS On the basis of the literature search, 1181 articles were screened, 320 abstracts were examined, and ninety full-text articles representing 5761 patients were reviewed in detail. Seventeen studies met the inclusion criteria for the analysis of pedicle screw placement accuracy. A total of 13,536 pedicle screws were placed in 1353 pediatric patients. The overall placement accuracy rate in pediatric patients was 94.9%, which was higher than the rate of 91.5% reported for adults. The weighted, geometric, and 5% trimmed mean accuracy rates of pedicle screw placement were 91.9%, 88.5%, and 89.1%, respectively (standard deviation = 10%; interquartile range = 10%). Sixteen comparative studies met the inclusion criteria for the analysis of the effect of pedicle screw instrumentation on scoliosis correction. Pedicle screw constructs had a significantly larger percentage of Cobb angle correction compared with hooks (Cohens d = 1.14) and hybrid constructs (Cohens d = 0.49). CONCLUSIONS The accuracy of pedicle screw placement in the pediatric spine exceeds the accuracy rate reported in adults. Pedicle screw instrumentation constructs are significantly more effective for scoliosis correction, as determined on the basis of Cobb angle measurements, than are hook constructs and hybrid constructs.

The accuracy of intraoperative O-arm images for the assessment of pedicle screw postion

Study Design. Human cadaveric study. Objective. The objective of the study was to determine the accuracy of intraoperative O-arm images in determining pedicle screw position using open dissection as the gold standard. Summary of Background Data. Pedicle screws are widely used in the treatment of various spinal disorders. Postoperative computed tomographic scans are the imaging gold standard to detect pedicle screw malposition. However, a second procedure is necessary if such malpositioned screws have to be revised. The O-arm is an intraoperative scanner that allows revision of a screw without having to return the patient to the operating room for a separate procedure. No previous studies have looked at the accuracy of intraoperative O-arm images in determining pedicle screw position. Methods. This factorial validation study utilized 9 cadavers in a comparison of intraoperative O-arm images and the dissection gold standard. Four hundred sixteen screws were inserted using 3-dimensional image (O-arm) guidance from C2 to S1. The screw positions were randomized into 3 groups: “IN” (fully contained within the pedicle), “OUT-lateral,” or “OUT-medial.” After screw insertion, O-arm images were obtained and reviewed in a blinded fashion by 3 independent observers. Dissection identified the true position of the screws. Specificity, sensitivity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using dissection results as the gold standard. The interobserver reliability was also determined. Results. The overall accuracy, specificity, sensitivity, PPV, and NPV of O-arm images for the thoracic and lumbar spine were 73%, 76%, 71%, 74%, and 72%, respectively. Accuracy of surgeon perception in the cervical spine was significantly less than in the thoracic and lumbosacral spine. There was substantial interobserver agreement between the 3 readers. Conclusion. Intraoperative O-arm images accurately detect significant pedicle screw violations in the thoracic and lumbosacral spine but are less accurate for the cervical spine.

Cost savings analysis of intrawound vancomycin powder in posterior spinal surgery

BACKGROUND CONTEXT Recent studies have shown that prophylactic use of intrawound vancomycin in posterior instrumented spine surgery substantially decreases the incidence of wound infections requiring repeat surgery. Significant cost savings are thought to be associated with the use of vancomycin in this setting. PURPOSE To elucidate cost savings associated with the use of intrawound vancomycin in posterior spinal surgeries using a budget-impact model. STUDY DESIGN Retrospective cohort study. PATIENT SAMPLE Data from a cohort of 303 patients who underwent spinal surgery (instrumented and noninstrumented) over 2 years were analyzed; 96 of these patients received prophylactic intrawound vancomycin powder in addition to normal intravenous (IV) antibiotic prophylaxis, and 207 received just routine IV antibiotic prophylaxis. Patients requiring repeat surgical procedures for infection were identified, and the costs of these additional procedures were elucidated. OUTCOME MEASURE Cost associated with the additional procedure to remediate infection in the absence of vancomycin prophylaxis. METHODS We retrospectively reviewed the cost of return procedures for treatment of surgical site infection (SSI). The total reimbursement received by the health care facility was used to model the costs associated with repeat surgery, and this cost was compared with the cost of a single local application of vancomycin costing about

The accuracy of navigation and 3D image-guided placement for the placement of pedicle screws in congenital spine deformity.

12. RESULTS Of the 96 patients in the treatment group, the return-to-surgery rate for SSI was 0. In the group without vancomycin, seven patients required a total of 14 procedures. The mean cost per episode of surgery, based on the reimbursement, the health care facility received was

Comparison of Cranial Facet Joint Violation Rates Between Open and Percutaneous Pedicle Screw Placement Using Intraoperative 3-D CT (O-arm) Computer Navigation

40,992 (range,

An analysis of decision making and treatment in thoracolumbar metastases.

14,459-

Biomechanical analysis of pedicle screw thread differential design in an osteoporotic cadaver model.

114,763). A total of

Utilization of Minimally Invasive Surgical Approach for Sacroiliac Joint Fusion in Surgeon Population of ISASS and SMISS Membership.

573,897 was spent on 3% of the 207-patient cohort that did not receive intrawound vancomycin, whereas a total of