Clinical Application Of Small Oblique View Of Lumbar Pedicle Screws Intraoperatively

Study Design: The trial is a retrospective study which contains somepedicles screws of malposition. Their data was collected and identified bythree orthopedics surgeon.Objective: The theory of Roy-camile is the fundament of internalfixation of pedicle screws. Pedicle screws can realize the stability of thethree columns and cure many disease such as fracture, congenital scoliosis andspondylolisthesis. The accuracy of pedicle screws is essential to avoidunnecessary complications. The axial view, robotic assistant technique,navigations and computer-assisted drill guide template was utilized to avoidthe perforation of pedicle of vertebra. But new problems such as operativetime, exposure radiation, high expense of maintenance and uses, rigidanatomical pairing and the separation of soft-tissue generated simultaneously.The objective of the study was to exploring a novel views and improve theaccuracy of pedicle screws inserting and verified the accuracy of little obliqueview in determining the pedicle screws. The views could popularize incommon hospital and correct the pedicle screws intraoperatively to reduce thecomplications concerning nerve and blood vessel.Material and method: The trial utilized25subjects in comparison of APX rays and oblique views. Their spines were examined with conventionalradiographs in two planes (anteroposterior and lateral) to exclude anomalies,tumors, and moderate spondylosis. Five subjects were excluded. Three had noimprovement about their serious neural symptoms after operation. One’ X rayswas not suitable for identifying and another lost his oblique views. There weresixteen male and four female with a mean age of41.Each subject was positioned prone on a radiolucent table. A straightmidline incision was made over the thoracic, and lumbosacral spine to exposethe posterior elements. The subjects were asked to conform an absolutely rest on bed. The drain tube was eradicated after twelve or twenty four hours andkept the wound clear. Mean operating time and mount of blood was ninetythree minutes, eight thousand milliliter respectively.One hundred twenty-six screws were determined after operations. Twofile set was established. One contains AP and lateral views and anothercontains little oblique and lateral views. Images were obtained and reviewedin a blinded fashion by3independent observers. CT scan identified the trueposition of the screws. Accuracy, specificity, sensitivity, positive predictivevalue (PPV), and negative predictive value (NPV) of three observers werecalculated totally and respectively using CT results as the gold standard.Chi-square and Fisher’ Exact Test was used to test the statistically differencesabout the position of the pedicle screws.Results: The overall accuracy, specificity, sensitivity, PPV, and NPV inAP views was88%,27%,98%,63%,90%and92%,50%,98%,86%,93%inoblique views. There was a statistically difference in three observers’comparisons (P=0, P=0, P=0.025<0.05). First observer identified4medialscrews and1lateral correctly through AP and lateral views,6medial screwsand3lateral screws through little oblique and lateral views. Another oneidentified2medial and1lateral through AP and lateral views,4medial and3laterals through little oblique and lateral views. The last observer identified5medial and1lateral correctly through AP and lateral views, and6medial and3lateral through little oblique views. In AP views, there was a consensus in106screws which one was identified wrongly, so105were recognizedcorrectly. In oblique views, there was a consensus in112screws which not onewas identified wrongly.Conclusions: Compared AP with lateral views, Oblique images couldimprove the accuracy of detecting pedicle screw violations statistically in thelow thoracic and lumbar spine. The malpositioned screws could be correctlyinstantly. It reduced the unnecessary iatrogenic injury.