Yuichirou Yokoyama

Ligamentum flavum haematoma: a report of two cases

We present 2 cases of ligamentum flavum haematoma causing root compression. Magnetic resonance imaging showed an epidural mass linked to the ligamentum flavum. The mass was isointense in T1-weighted images, and was centrally hyperintense and peripherally hypointense in T2-weighted images. Surgical removal of the ligamentum flavum achieved resolution of the symptoms. The definitive diagnosis could only be confirmed by histopathological examinations. The differential diagnoses include lumbar disc herniation and lumbar spinal canal stenosis caused by neoplasm, infection, epidural haematoma, or facet cyst.

Spontaneous Symptomatic Pseudoarthrosis at the L2-L3 Intervertebral Space with Diffuse Idiopathic Skeletal Hyperostosis: A Case Report

Pseudoarthrosis at the intervertebral space in patients with ankylosing spondylitis has occasionally been reported, but symptomatic pseudoarthrosis at the intervertebral disc level is rare in patients with diffuse idiopathic skeletal hyperostosis (DISH). Here, we report a case of symptomatic pseudoarthrosis at the L2-L3 intervertebral space that was diagnosed based on clinical history. We first performed L1–L5 fixation, but back-out of the pedicle screw occurred in the early postoperative phase and may have been caused by a short fixation range and concomitant Parkinsons disease. However, the prognosis of the case was favorable after a second surgery. This case indicates that a fixation range of at least 3 above and 3 below is necessary for bone fracture of a thoracolumbar vertebra and pseudoarthrosis in patients with DISH.

Solitary Spinal Epidural Metastasis from Gastric Cancer

Solitary epidural space metastasis of a malignant tumor is rare. We encountered a 79-year-old male patient with solitary metastatic epidural tumor who developed paraplegia and dysuria. The patient had undergone total gastrectomy for gastric cancer followed by chemotherapy 8 months priorly. The whole body was examined for suspected metastatic spinal tumor, but no metastases of the spine or important organs were observed, and a solitary mass was present in the thoracic spinal epidural space. The mass was excised for diagnosis and treatment and was histopathologically diagnosed as metastasis from gastric cancer. No solitary metastatic epidural tumor from gastric cancer has been reported in English. Among the Japanese, 3 cases have been reported, in which the outcome was poor in all cases and no definite diagnosis could be made before surgery in any case. Our patient developed concomitant pneumonia after surgery and died shortly after the surgery. When a patient has a past medical history of malignant tumor, the possibility of a solitary metastatic tumor in the epidural space should be considered.

Comparison of the invasiveness of conventional discectomy and microendoscopic discectomy for lumbar disc herniation: Differences in the methods of approach.

The aim of this study was to investigate whether differences in the methods of approach to the vertebral arch influence the invasiveness of conventional discectomy and microendoscopic discectomy (MED).

Use of intrawound vancomycin powder against postoperative infection after spine surgery

Local application of vancomycin has recently become widely used in spine surgery. However, local application is not included in the indication and has not been approved by the US Food and Drug Administration (FDA). Thus, we searched for reports with “intra wound-vancomycin” and “SSI” as keywords in the MEDLINE database, and investigated the efficacy, problems with use, and future prospects based on these reports. Intrawound vancomycin was described as effective in most of the reports, but was found to have no effect or to aggravate the condition in some reports. A toxic effect on osteoblasts due to a high local concentration was described in some reports, whereas local application was found to be safe in other studies. The amount of vancomycin used and the administration method varied among the reports. Overall, the results suggest that intrawound vancomycin is clinically effective, but this has yet to be established in a randomized controlled trial. There is a need to identify cases that should be selected for this treatment and to investigate the dose and optimum concentration of vancomycin for clinical use.

Evaluation of antimicrobial prophylaxis against postoperative infection after spine surgery: Limit of the first generation cephem.

In our department, first-generation cephem (CEZ) are generally administered for 2 days as antimicrobial prophylaxis (AMP) for spinal surgery. However, the incidence of surgical site infection (SSI) has recently increased, particularly cases involving coagulase-negative Staphylococci (CNS) as an etiologic agent. The objective was to elucidate the problems with the current AMP and the risk factors of SSI through a retrospective investigation of affected cases. The subjects were patients who underwent spine surgery at our department between August 2007 and June 2013. The subjects were divided into those who developed SSI (S group) and who did not develop SSI (non-SSI (N) group), patients who developed CNS infection in the S group was subdivided as C group, and the risk factors were investigated. The significance of each factor was analyzed using cross tabulation, and multivariate logistic regression analyses were performed with 22 of the investigation factors as explanatory variables. The incidence of SSI was 2.55%, and the etiologic agent was CNS in 17 patients. Upon comparison between the S and N groups, the presence of 3 or more underlying diseases and blood loss were extracted as significant risk factors. Upon comparison between the C and N groups, emergency surgery and intra- and postoperative steroid administration were extracted as significant risk factors, in addition to the presence of 3 or more underlying diseases and blood loss. The effect of the current AMP using first generation cephem is limited, and reconsideration of the protocol may be necessary.

Surgical Strategy for a Retro-Odontoid Pseudotumor

Surgical Strategy for a Retro-Odontoid Pseudotumor Retro-odontoid pseudotumors that are not associated with rheumatoid arthritis or hemodialysis are clinically rare. A pseudotumor is a non-neoplastic mass in the retro-odontoid region that can occur in elderly people. Retro-odontoid pseudotumors are regarded as non-neoplastic masses that arise as a result of instability of the atlantoaxial joint. However, Retro-odontoid pseudotumor has occasionally been reported without instability on dynamic radiography.