Tomoya Yamashita

Cervical myelopathy caused by invagination of anomalous lamina of the axis

The authors report a case of cervical myelopathy caused by invagination of the bilaterally separated lamina of the axis. They also present a literature review. The patient was a previously healthy 68-year-old man with a 1-year history of slowly progressive gait disturbance, right-hand clumsiness, and right dominant sensory disturbance in his trunk and extremities. Both MRI and CT showed that the spinal cord was markedly compressed at the C2-3 level, on the right side, by a deeply invaginated anomalous lamina of the axis. A bilaterally separated lamina was also visible. The patient underwent removal of the anomalous invaginated fragment of the separated lamina and the spinous process of the axis. One year after surgery, his myelopathic symptoms had almost completely resolved. Here, the authors present the case of a patient with an extremely rare anomaly of the lamina of the axis. The underlying pathogenesis of this anomaly could be the failure of the 2 chondrification centers on either side to fuse into a single ossification center. Surgical removal of the anomalous invaginated lamina produced a satisfactory outcome.

Data Acquisition for Stochastic Localization of Wireless Mobile Client in Multistory Building

This paper describes a method for the localization of wireless mobile clients in multistory buildings using a wireless LAN system. The method uses public wireless LAN access points for users and robots that are settled at many places in a multistory building. Data on the physical position of personal electronic devices or mobile robots are important in information services and robot applications for construction automation such as the maintenance task in the large scale building. By integrating the data and stored information on objects and places, people and robots can be provided with information on the location of the devices for achieving the tasks. The localization method using few devices is expected for real application such as a navigation of the mobile robots, information services for users who have mobile clients. The paper focuses on the data acquisition for stochastic localization of the wireless LAN client in multistory building. The data acquisition is a crucial issue for making and verification of the localization system. Experimental results show feasibility of the proposed method.

Factors associated with patient satisfaction for PLIF: Patient satisfaction analysis

Introduction: Posterior lumbar interbody fusion (PLIF) has produced satisfactory clinical outcomes; however, all previous reports have only included evaluations by surgeon-based methods. The purpose of this study was to investigate patient-based surgical outcomes and the factors associated with patient satisfaction for PLIF. Methods: Patients who underwent PLIF for lumbar spondylolisthesis were reviewed (n=443). The average follow-up period was 8 years. Surgical outcomes were assessed using an original questionnaire, a numerical rating scale (NRS), the 36-Item Short Form Health Survey (SF-36), the Japanese Orthopedic Association (JOA) score, and the recovery rate. The original questionnaire consisted of five categories, with patient-evaluated score out of 100 points for surgery, satisfaction, improvement, recommendation to others, and willingness to undergo repeat surgery on a 5-point scale. According to the questionnaire responses, patient-based outcomes were divided into three groups: positive, intermediate, and negative and were compared with the NRS, SF-36, and JOA scores. Furthermore, factors associated with patient satisfaction were examined. Results: A total of 273 patients responded. Response rate was 62%. The average patient-evaluated score for surgery was 82 points. In terms of satisfaction section, positive, intermediate, and negative response rates were 82%, 7%, and 11%, respectively. With respect to other sections, positive, intermediate, and negative response rates were 87%, 7%, and 6% in improvement section; 66%, 23%, and 11% in recommending section; and 72%, 18%, and 10% in repeat section, respectively. The average pre- and postoperative JOA scores were 12 and 24, respectively. Significant correlations were detected between patient-based surgical outcomes and the NRS scores, physical component scores of the SF-36, and the JOA score. Postoperative permanent motor loss and multiple revision surgery were the major factors related to a negative response. Conclusions: High satisfaction rate to PLIF and significant correlation between patient- and surgeon-based surgical outcomes were detected. Postoperative permanent motor loss and multiple revision surgery were the major factors related to a negative response.

Radiculopathy Due to Fracture of an Inferior Articular Process Anomaly at the 5th Lumbar Vertebra: A Case Report

Radiculopathy Due to Fracture of an Inferior Articular Process Anomaly at the 5th Lumbar Vertebra: A Case Report This case report details lumbar radiculopathy due to fracture of an inferior articular process anomaly. The inferior articular process at the 5th lumbar vertebra bifurcated to both ventral and dorsal sides of the superior articular process at the sacrum. The ventral spur was fractured and lay just dorsal to the L5 nerve root. Although this anomaly could not be classified as congenital or acquired, this ventral spur was speculated to be fractured by high-energy trauma, resulting in compression of the nerve root.