The XVS System During Open Spinal Fixation Procedures in Patients Requiring Pedicle Screw Placement in the Lumbosacral Spine.

OBJECTIVE: This pilot study was undertaken to evaluate the safety, performance, and usability of the Xvision-Spine (XVS) System (Augmedics, Arlington Heights, IL) during open spinal fixation procedures in patients requiring pedicle screw placement in the lumbosacral spine. METHODS: The XVS System is an augmented reality head-mounted display (HMD) based on a computer navigation system designed to assist surgeons in accurately placing pedicle screws. It uses an HMD-mounted tracking camera to provide optical tracking technology, and provides the surgeon a translucent direct near-eye display of the navigated surgical instrument's location relative to the computed tomographic image. We report the preliminary results of a prospective series of all consecutive patients who underwent augmented reality-assisted pedicle screw placement in the lumbosacral vertebrae at 3 institutions. Clinical accuracy for each pedicle screw was graded with Gertzbein-Robbins scores by 2 independent and blinded neuroradiologists. RESULTS: The 19 study participants included 8 men and 11 women with a mean age of 59.13 ± 12.09 and 59.91 ± 12.89 years, respectively. Seventeen procedures were successfully completed via the XVS System. Two procedures were not completed due to technical issues with the system's intraoperative scanner. A total of 86 screws were inserted. The accuracy of the XVS System was 97.7%. CONCLUSIONS: The XVS System's performance in accurate placement of pedicle screws in the lumbosacral vertebrae had an overall accuracy of 97.7%. These preliminary results were comparable to the accuracy of other manual computer-assisted navigation systems reported in the literature.

Reliability of smartphone-based teleradiology for evaluating thoracolumbar spine fractures.

BACKGROUND CONTEXT: Timely interpretation of computed tomography (CT) scans is of paramount importance in diagnosing and managing spinal column fractures, which can be devastating. Out-of-hospital, on-call spine surgeons are often asked to evaluate CT scans of patients who have sustained trauma to the thoracolumbar spine to make diagnosis and to determine the appropriate course of urgent treatment. Capturing radiographic scans and video clips from computer screens and sending them as instant messages have become common means of communication between physicians, aiding in triaging and transfer decision-making in orthopedic and neurosurgical emergencies. PURPOSE: The present study aimed to compare the reliability of interpreting CT scans viewed by orthopedic surgeons in two ways for diagnosing, classifying, and treatment planning for thoracolumbar spine fractures: (1) captured as video clips from standard workstation-based picture archiving and communication system (PACS) and sent via a smartphone-based instant messaging application for viewing on a smartphone; and (2) viewed directly on a PACS. STUDY DESIGN: Reliability and agreement study. PATIENT SAMPLE: Thirty adults with thoracolumbar spine fractures who had been consecutively admitted to the Division of Orthopedic Surgery of a Level I trauma center during 2014. OUTCOME MEASURE: Intraobserver agreement. METHODS: CT scans were captured by use of an iPhone 6 smartphone from a computer screen displaying PACS. Then by use of the WhatsApp instant messaging application, video clips of the scans were sent to the personal smartphones of five spine surgeons. These evaluators were asked to diagnose, classify, and determine the course of treatment for each case. Evaluation of the cases was repeated 4 weeks later, this time using the standard method of workstation-based PACS. Intraobserver agreement was interpreted based on the value of Cohen's kappa statistic. The study did not receive any outside funding. RESULTS: Intraobserver agreement for determining fracture level was near perfect (κ=0.94). Intraobserver agreement for AO classification, proposed treatment, neural canal penetration, and Denis classification were substantial (κ values, 0.75, 0.73, 0.71, and 0.69, respectively). Intraobserver agreement for loss of vertebral height and kyphosis were moderate (κ values, 0.55 and 0.45, respectively) CONCLUSIONS: Video clips of CT scans can be readily captured by a smartphone from a workstation-based PACS and then transmitted by use of the WhatsApp instant messaging application. Diagnosing, classifying, and proposing treatment of fractures of the thoracic and lumbar spine can be made with equal reliability by evaluating video clips of CT scans transmitted to a smartphone or by the standard method of viewing the CT scan on a workstation-based PACS. Evaluating video clips of CT scans transmitted to a smartphone is a readily accessible, simple, and inexpensive method. We believe that it can be reliably used for consultations between the emergency physicians or orthopedic or neurosurgical residents with offsite, on-call specialists. It might also enable rural orcommunity emergency department physicians to communicate more efficiently and effectively with surgeons in tertiary referral centers.

[Posterior lumbar interbody fusion (PLIF stand-alone) for chronic low back pain].

OBJECTIVE: To evaluate the fusion achieved by posterior lumbar interbody fusion--PLIF [B-TWIN, Disc-O-Tech) stand-alone in terms of intervertebral fusion on the basis of radiograph imaging. SUMMARY OF BACKGROUND DATA: Lumbar fusion is being used to reduce pain and decrease disability in patients with chronic low back pain. Different surgical techniques are available. The use of PLIF stand-alone has been described with controversial results. METHODS: From 2003 through 2006, 14 patients with chronic low back pain were operated on in our department. In order to evaluate the quality of fusion, flexion and extension, radiographs were performed. A difference of 4 degrees was considered as failure of fusion. RESULTS: A total of 14 patients, 5 male and 9 female mean age 56 years (43-72), underwent 15 lumbar interbody fusions. Fourteen lumbar interbody fusions (93%) had less than 4 degrees of difference between flexion and extension radiographs; the overall median score was 1.7 degrees, the male group had a median score of 2.9 and the female group 1.1 (P = 0.066]. All the patients with degenerative disc disease had scores above 1.7 degrees, 57% (4) of the patients with spondylolisthesis had scores above 1.7 degrees and 1 patient (16% of this group) with spinal stenosis had a score above 1.7 degrees (P = 0.096). CONCLUSIONS: A fusion rate of 93% was achieved. The findings suggested a tendency for better results in the female group and better results in the spinal stenosis group compared with the spondylolisthesis group and the degenerative disc disease group. There is a need for further investigation in order to establish our findings.

[Congenital cervical spondylolisthesis].

Cervical spondylolysis with spondylolisthesis is a complex abnormality involving the posterior elements of the cervical vertebra, and anterolisthesis of the same vertebra. Cervical spondylolysis is defined as a corticated cleft between the superior and inferior articular facets of the articular "pillar", the cervical equivalent of the pars intraarticularis in the lumbar spine. The typical radiological features of this condition are as follows: 1. Spondylolysis (a break in the "pillar" on one or both sides) 2. Spina bifida of dysplastic vertebra 3. Affection of posterior intervertebral joints (abnormal inclination of the superior and inferior articular facets of the affected bones may present) Recognition of this congenital disorder and its differentiation from traumatic injury is extremely important in patients who have a history of recent cervical trauma.