Results of Using a Novel Percutaneous Pedicle Screw Technique for Patients with Diffuse Idiopathic Skeletal Hyperostosis-The Single or Double Endplates Penetrating Screw (SEPS/DEPS) Technique

Introduction

We have developed the single or double endplates penetrating screw (SEPS/DEPS) technique, which is a novel percutaneous pedicle screw (PPS) insertion technique suitable for osteoporotic vertebral body fracture (OVF) patients with diffuse idiopathic skeletal hyperostosis (DISH). This study aims to compare the effectiveness of this SEPS/DEPS technique with the conventional pedicle screw technique.

Methods

The screw is inserted upward from the outer caudal side of the pedicle toward the inner cranial side. Vertebrae affected with DISH were inserted with screws using the SEPS/DEPS technique, whereas non-fused vertebrae were inserted with screws using the conventional PPS technique. Twelve OVF patients with DISH were included in this study; three with SEPS/DEPS technique only and nine with a hybrid of both the DEPS and the conventional PPS techniques. As a control group, 12 OVF patients with DISH treated by conventional PPS. The rates of implant failures and of surgical complications were compared between the SEPS/DEPS group and the control group. The insertion torque was measured and compared between DEPS and conventional PPS in three hybrid patients.

Results

In the SEPS/DEPS group, 70 screws were inserted with the SEPS/DEPS technique and 56 screws were inserted with the conventional PPS technique. In the control group, 116 screws were inserted using the conventional PPS and the PS techniques. The loosening of screws was significantly less in screws inserted with the SEPS/DEPS technique (0/70 screws, 0%) than with screws inserted with the conventional technique (12/116 screws, 10.3%). The average insertion torque of DEPS was 2.25 Nm, which was 134% higher than that of conventional PPS which was 1.64 Nm (p = 0.04).

Conclusions

This novel SEPS/DEPS technique has a higher insertion torque compared with the conventional PPS techniques and demonstrated itself to be an effective option for patients with concomitant bone fragility due to DISH.

P5650Improvement in ejection fraction predicts heart failure after catheter ablation for atrial fibrillation in patients with left ventricular systolic dysfunction: from the KPAF registry

Introduction

The presence of atrial fibrillation (AF) in patients with reduced left ventricular ejection fraction (LVEF) is associated with increased risks of mortality and hospitalization for heart failure (HF). Although prior studies reported that catheter ablation (CA) for AF in low LVEF patients reduced risks of all-cause mortality and HF hospitalization, the predictors of worsening HF after ablation has not been adequately evaluated.

Purpose

The purpose of this study was to investigate the impact of improvement in LVEF after AF ablation on the incidence of subsequent HF hospitalization in patients with low LVEF.

Methods

The Kansai Plus Atrial Fibrillation (KPAF) Registry is a multicenter registry enrolling 5,013 consecutive patients undergoing first-time ablation for AF. The current study population consisted of 1,031 patients with reduced LVEF of <60%. We divided the study population into 3 groups according to LVEF at follow-up; 678 patients (65.8%) with improved LVEF (≥5 U change in LVEF), 288 patients (27.9%) with unchanged LVEF (−5 U ≤ change in LVEF <5 U) and 65 patients (6.3%) with worsened LVEF (<−5 U change in LVEF).

Results

During the median follow-up of 1067 [879–1226] days, patients improved LVEF had lower rate of HF hospitalization, compared with those with unchanged and worsened LVEF (2.1%, 8.0%, and 21.5%, respectively, P<0.0001). Recurrent atrial tachyarrhythmias were documented in 43.5%, 47.2% and 67.7%, respectively (P=0.0008).

Figure 1

Conclusion

Among patients with reduced LVEF undergoing AF ablation, patients with subsequently improved LVEF in association with maintained sinus rhythm had markedly lower risk of HF hospitalization during follow-up as compared with those with unchanged or worsened LVEF.

Mechanism of forelimb motor function restoration in rats with cervical spinal cord hemisection-neuroanatomical validation

Purpose

The purpose of this study is neuroanatomical validation of forelimb motor function restoration in rats with cervical spinal cord injury.

Materials and methods

We used eight cervical hemisected rats and eight normal rats. We cut in half the C3/4 cervical spinal cord of 18-weeks-old normal rats. We used 24-weeks-old rats that had reached a nearly steady state of forelimb motor function after the hemisection (Hemisection group). Normal 24-week-old rats were used as Control group. To evaluate the corticospinal tracts, neuro-tracing by biotynirated dextran-amine (BDA) was used. BDA was injected into the damaged side of the cerebral primary motor cortex. In order to quantitatively analyze the specimen, we recorded a site where nerve fibers appear in each specimen in the image analysis (1) and defined the increase rate of immunostaining area using ImageJ in the image analysis (2). Based on the evaluation in the image analysis (1) and the image analysis (2), the Hemisection group and the Control group were compared.

Results

In the image analysis (1), a region with robust appearance of aberrant nerve fibers was observed in the cephalad side of the Hemisection site in Hemisection group than Control group. In the spinal cord caudal to the hemisection, such region was generally more in Hemisection group, however, disappeared or reduced appearance was observed in some regions. In the image analysis (2), no statistical significant difference was noted in each level.

Conclusion

There is a high probability that these aberrant nerve fibers beyond the midline could be involved in forelimb motor function restoration in rats with cervical cord hemisection.

Intratumoural immune cell landscape in germinoma reveals multipotent lineages and exhibits prognostic significance

AIMS

Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown.

METHODS

We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases.

RESULTS

Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression-free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in-situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte-lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD-L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%).

CONCLUSIONS

The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies.

Potential asbestos exposure among patients with primary lung cancer in Japan

Objective:

To investigate the extent of asbestos exposure among patients with primary lung cancer in Japan.

Methods:

A retrospective estimation of potential asbestos-exposed individuals, as determined by the presence of pleural plaques identified on chest computed tomography (CT), was conducted on 885 pathologically confirmed primary lung cancer patients (mean age 71.3 years, 641 males). All patients were diagnosed at 29 hospitals across Japan between 2006 and 2007. Since these hospitals belong to the Japan Federation of Democratic Medical Institutions (MIN-IREN), an organization of medical institutions for workers, the study subjects may contain a higher proportion of workers than the general population.

Results:

Pleural plaques were identified in 12.8% of subjects (15.8% in males and 4.9% in females), consisting exclusively of cases older than 50 years. They were found most frequently on the chest wall pleura (96.5%), followed by the diaphragm (23.9%) and mediastinum (9.7%). Calcifications were seen in 47 cases (41.6%). The highest prevalence of pleural plaques was seen among workers from construction-related fields (37.7%). No distinct lung cancer histology was observed in patients with pleural plaques. Coexistence of pleural plaques and small irregular opacities was observed in 2.5% of subjects.

Conclusion:

In a Japanese population representing more workers than general Japanese, 12.8% of patients with primary lung cancer may have experienced asbestos exposure at some time in the past. Special medical attention should be paid to individuals with a history of employment in construction-related occupations, as workers in this sector showed the highest prevalence of pleural plaques.

What Is the Best Multimodality Combination for Intraoperative Spinal Cord Monitoring of Motor Function? A Multicenter Study by the Monitoring Committee of the Japanese Society for Spine Surgery and Related Research

Study Design Surgeon survey. Objective To analyze multimodal intraoperative monitoring (MIOM) for different combinations of methods based on the collected data and determine the best combination. Methods A questionnaire was sent to 72 training institutions to analyze and compile data about monitoring that had been conducted during the preceding 5 years to obtain data on the following: (1) types of monitoring; (2) names and number of diseases; (3) conditions of anesthesia; (4) condition of stimulation, the monitored muscle and its number; (5) complications; and (6) preoperative and postoperative manual muscle testing, presence of dysesthesia, and the duration of postoperative motor deficit. Sensitivity and specificity, false-positive rates, and false-negative rates were examined for each type of monitoring, along with the relationship between each type of monitoring and the period of postoperative motor deficit. Results Comparison of the various combinations showed transcranial electrical stimulation motor evoked potential (TcMEP) + cord evoked potential after stimulation to the brain (Br-SCEP) combination had the highest sensitivity (90%). The TcMEP + somatosensory evoked potential (SSEP) and TcMEP + spinal cord evoked potential after stimulation to the spinal cord (Sp-SCEP) combinations each had a sensitivity of 80%, exhibiting little difference between their sensitivity and that obtained when TcMEP alone was used. Meanwhile, the sensitivity was as low as 50% with Br-SCEP + Sp-SCEP (i.e., the cases where TcMEP was not included). Conclusions The best multimodality combination for intraoperative spinal cord monitoring is TcMEP + Br-SCEP, which had the highest sensitivity (90%), the lowest false-positive rate (6.1%), and the lowest false-negative rate (0.2%).

Development of Stemness in Cancer Cell Lines Resistant to the Anticancer Effects of Zoledronic Acid

BACKGROUND

Drug resistance is closely related to cancer cell stemness, that is acquired along with resistance to various anticancer agents. However, this has not been investigated as a potential mechanism underlying cancer cell resistance to zoledronate, that is used to suppress bone metastasis.

MATERIALS AND METHODS

Zoledronate-resistant A549 lung cancer and MG63 osteosarcoma cell lines were established by repeated treatment with sub-lethal concentrations of zoledronate. Expression levels of the stem cell marker NANOG, cMYC, octamer-binding transcription factor 4, and sex-determining region Y-box 2 were evaluated and sphere formation was compared between parental and resistant cell lines. Tumourigenicity was assessed in vivo.

RESULTS

Stem cell marker expression was up-regulated and sphere formation was enhanced in resistant compared to parental cells and showed greater tumour formation capacity in mice.

CONCLUSION

Repeated treatment of malignant tumour cell lines with zoledronate, induces the development of drug resistance and stemness.

Physical Function Traits of Long-term Officially Acknowledged Victims of Pollution-related Illnesses Compared with Elderly Patients with Chronic Obstructive Pulmonary Disease

[Purpose] To examine the long-term effects of air pollution on the physical functioning of a group of officially acknowledged victims of pollution-related illnesses (Victims group) who were exposed to air pollution more than 50 years ago, we compared them with age-matched patients with chronic obstructive pulmonary disease (COPD group). [Subjects and Methods] The Victims group comprised 34 subjects and the COPD group 24, all of whom were aged over 65 years. Respiratory function, muscle strength, exercise capacity and physical activity were measured and compared between the groups. [Results] The Victims group had significantly higher forced expiratory volume in the first second (FEV1), proportion of predicted FEV1, proportion of predicted vital capacity (VC), and ratio of FEV1 to forced VC than the COPD group. Surprisingly, the muscle strength of the Victims group was significantly weaker, their incremental shuttle walking test distance was significantly shorter, and their physical activity was significantly less than those of the COPD group. [Conclusion] Although the pulmonary function of Victims was better than that of the COPD group, their physical functioning was worse. Exposure to air pollution 50 years ago appears to continue to adversely affect their physical function. It is particularly important to offer Victims rehabilitation to improve their exercise performance and physical activity.

D-dimer levels in the differential diagnosis between lipoma and well-differentiated liposarcoma

BACKGROUND

Lipoma and well-differentiated liposarcoma (WDLS) are two representative lipogenic soft tissue tumors that have similar clinical, radiological, and pathological characteristics. Accordingly, it is difficult to distinguish these tumors preoperatively. Plasma D-dimer levels are associated with the status of tumor progression, and we hypothesized that D-dimer levels could contribute to differential diagnosis. The D-dimer levels of these two entities have not yet been reported.

PATIENTS AND METHODS

We investigated 43 cases of lipoma and 14 cases of WDLS. We evaluated the utility of D-dimer levels and other clinicopathological factors for preoperative differential diagnosis between the two entities.

RESULTS

Receiver operating characteristic analysis revealed that the D-dimer level may contribute to differential diagnosis (area under the curve=0.73). Univariate and multivariate models demonstrated that plasma D-dimer levels (p=0.001 (univariate), and p=0.006 (multivariate)) and lower extremity location (p=0.006 (univariate), and p=0.03 (multivariate)) were independent risk factors for WDLS.

CONCLUSION

The D-dimer level may be a helpful marker for preoperative differential diagnosis between lipoma and WDLS.

Lung cancer cell line sensitivity to Zoledronic acid is BAX-dependent

BACKGROUND

Zoledronate (Zol), an anti-osteoclastic and anticancer drug, is used to control bone metastasis in several cancer types, including non-small cell lung cancer (NSCLC). However, the mechanisms behind Zol resistance in NSCLC are unclear.

MATERIALS AND METHODS

Zol-resistant cell lines were developed by repeated treatment of A549 and H1650 NSCLC cell lines with Zol. We measured cell proliferation and apoptosis following Zol treatment and also examined the BCL2 superfamily expression. RNAi was used to confirm the role of key molecules in development of resistance.

RESULTS

Repeated Zol treatment engendered resistance, in which apoptosis induction was attenuated. From the BCL2 superfamily, BAX was commonly down-regulated in resistant cells, and silencing of BAX in parental cell lines also induced drug resistance.

CONCLUSION

Repeated treatment of NSCLC cell lines with Zol leads to drug resistance, which is in part due to BAX down-regulation.

A new alarm point of transcranial electrical stimulation motor evoked potentials for intraoperative spinal cord monitoring: a prospective multicenter study from the Spinal Cord Monitoring Working Group of the Japanese Society for Spine Surgery and Related Research

OBJECT

Although multimodal intraoperative spinal cord monitoring provides greater accuracy, transcranial electrical stimulation motor evoked potential (TcMEP) monitoring became the gold standard for intraoperative spinal cord monitoring. However, there is no definite alarm point for TcMEPs because a multicenter study is lacking. Thus, based on their experience with 48 true-positive cases (that is, a decrease in potentials followed by a new neurological motor deficit postoperatively) encountered between 2007 and 2009, the authors set a 70% decrease in amplitude as the alarm point for TcMEPs.

METHODS

A total of 959 cases of spinal deformity, spinal cord tumor, and ossification of the posterior longitudinal ligament (OPLL) treated between 2010 and 2012 are included in this prospective multicenter study (18 institutions). These institutions are part of the Japanese Society for Spine Surgery and Related Research monitoring working group and the study group on spinal ligament ossification. The authors prospectively analyzed TcMEP variability and pre- and postoperative motor deficits. A 70% decrease in amplitude was designated as the alarm point.

RESULTS

There were only 2 false-negative cases, which occurred during surgery for intramedullary spinal cord tumors. This new alarm criterion provided high sensitivity (95%) and specificity (91%) for intraoperative spinal cord monitoring and favorable accuracy, except in cases of intramedullary spinal cord tumor.

CONCLUSIONS

This study is the first prospective multicenter study to investigate the alarm point of TcMEPs. The authors recommend the designation of an alarm point of a 70% decrease in amplitude for routine spinal cord monitoring, particularly during surgery for spinal deformity, OPLL, and extramedullary spinal cord tumor.

D-dimer levels as a prognostic factor for determining oncological outcomes in musculoskeletal sarcoma

Background

Plasma d-dimer levels have been associated with the status of tumor progression or oncological outcomes in cancer. Although there are many evidences suggesting the involvement of procoagulant trend in musculoskeletal sarcoma, no clinical data on d-dimer levels and oncological outcome of musculoskeletal sarcoma has been reported.

Methods

In this study, we included a total of 85 patients who were diagnosed with musculoskeletal sarcoma and treated at our institute. Plasma d-dimer levels were determined before performing any clinical intervention, including open biopsy, chemotherapy, radiotherapy or tumor resection. We evaluated the effect of d-dimer levels and other clinicopathological factors on oncological outcomes of patients.

Results

Upregulation of plasma d-dimer levels proved to be an independent risk factor for metastasis and lethal outcome of patients with musculoskeletal sarcoma.

Conclusions

Upregulation of plasma d-dimer levels were indicated poor oncological outcome in metastasis and total survival rate of musculoskeletal sarcoma patients. Hence d-dimer levels may be a helpful marker for evaluating the tumor progression status and prognosis of musculoskeletal sarcoma.

Functional assessment of proximal arm muscles by target-reaching movements in patients with cervical myelopathy

BACKGROUND CONTEXT

In animal studies, distal and proximal arm movements are differently affected by spinal pyramidotomy because of the contributions of spinal interneuronal systems. In animals, interneuronal systems are also suggested to contribute to the recovery of dexterous hand movements. However, no clinical tests to evaluate proximal arm movements and functions of interneuronal systems have been described.

PURPOSE

To compare parameters from proximal arm movements between patients and controls and in patients before and after decompression surgery.

STUDY DESIGN

A cross-sectional and longitudinal study performed at Kyorin University School of Medicine, Japan.

PATIENT SAMPLE

Patients with clinical features of cervical spondylotic myelopathy, without coexisting neurological abnormality.

METHODS

Twenty-eight patients and 15 age-matched controls performed reach-to-touch movements. Analysis of these movements identified several parameters, including time for online correction (correction time) induced by sudden target jump. Parameters were compared with scores from conventional tests, such as Japanese Orthopedic Association (JOA) score, 10-second grip-and-release test, manual muscle testing, and motor-evoked potential.

RESULTS

Preoperatively, patients showed long correction time and variable touch position, neither of which correlated with any scores from conventional tests. Reaching parameters recovered markedly immediately after decompression surgery, whereas conventional scores, which mainly assess hand functions, recovered much more slowly. Correction time and JOA score showed correlations when postoperative data were included, and long-term recovery of JOA score was more predictable with the inclusion of data for correction times from before and immediately after surgery.

CONCLUSION

Analysis of arm movements is useful to evaluate symptoms and predict recovery of hand functions after surgery in patients with cervical myelopathy. These results suggest the importance of interneuronal systems, in addition to the pyramidal tract, for motor control even in humans.

Malignant pigmented villonodular synovitis in the knee - report of a case with rapid clinical progression

Malignant pigmented villonodular synovitis (PVNS) (or malignant giant cell tumor of tendon sheath (GCTTS) is an extremely rare condition defined as a malignant lesion occurring with concomitant or previously documented PVNS at the same site. To date, only less than 20 cases have been reported in English literatures. We report a case of malignant PVNS in the knee in a 56-year-old woman with unpredictable rapid progression. This case raised a caution that when atypical components in specimens of recurrent benign PVNS are detected, even if low-grade or tiny, both pathologists and surgeons should consider the risk of malignant PVNS, which could display aggressive clinical progression.

Inhibition of heat-shock protein 27 expression eliminates drug resistance of osteosarcoma to zoledronic acid

BACKGROUND

Although zoledronic acid (ZOL) has been reported to show anti-tumour effects on various malignant tumours, few studies have reported the molecular mechanisms of resistance to ZOL.

MATERIALS AND METHODS

A drug-resistant cell line was developed by repeatedly treating human osteosarcoma cell line HOS with ZOL. Expression status of drug resistance-related molecules including ATP-binding cassette (ABC) and heat-shock protein 27 (HSP27) was confirmed in order to analyse molecular mechanisms of the drug resistance.

RESULTS

Repeated treatment with ZOL induced drug resistance with down-regulation of apoptosis in the resistant cell line. Although ABC expression was down-regulated, up-regulation of HSP27 in the resistant cell line was confirmed. The resistance was overcome by HSP27 silencing.

CONCLUSION

Resistance to ZOL in osteosarcoma cells may be induced by a molecular mechanism different from conventional efflux pump-based resistance. Up-regulation of HSP27 expression may play a role in the development of ZOL resistance in HOS cells.

Short-term postoperative mortality events in patients over 80 years of age with hip fracture: analysis at a single institution with limited medical resources

BACKGROUND

Lethal events represent the most important complication in the treatment of hip fracture in elderly patients. Despite the increasing chance for treatment of such conditions, few data regarding risk factors associated with lethal events have been determined for ordinary hospitals with limited medical and human resources, particularly in Japan.

METHODS

The incidence of postoperative lethal events and related preoperative risk factors in extremely elderly patients (>80 years) with hip fracture were retrospectively analyzed in our hospital for the past 2 years.

RESULTS

Lethal events occurred in 11 (10.7%) of 103 patients within 3 months postoperatively. In both univariate and multivariate analyses, an elevated number of co-morbidities and preoperative respiratory dysfunction were identified as significant risk factors. Delay in surgery was not a risk factor for lethal events.

CONCLUSIONS

A valid reason for delay is the need to stabilize concurrent medical conditions due to multiple co-morbidities in extremely elderly patients with hip fracture. Considering the limited resources and extreme age of the subjects, the mortality rate in the present study was quite acceptable. Patients, families of patients, and physicians should recognize the increased risk of mortality for patients with significant risk factors in the surgical treatment of hip fracture.

Postoperative deep infection in tumor endoprosthesis reconstruction around the knee

BACKGROUND

Although deep infection remains one of the most difficult complications to manage in the treatment of musculoskeletal tumor reconstructed with an endoprosthesis, limited information with respect to its incidence and risk factors has been reported.

METHODS

This multicenter, retrospective, uncontrolled study reviewed the medical records of 82 patients who underwent reconstruction with an endoprosthesis or temporary spacer for bone-immature patients after resection of malignant bone tumor around the knee. Risk factors for deep infection and the impact of deep infection on prosthesis survival and oncological outcomes were analyzed. Deep infection was defined according to the Centers for Disease Control and Prevention (CDC) guidelines with minor modification.

RESULTS

Deep infection occurred in 14 cases (17%), identified at a mean of 10.9 months (range <1 to 48 months) after initial surgery. Univariate analysis identified surface infection (P < 0.001) and skin necrosis (P < 0.001) as risk factors associated with deep infection. Conversely, tumor origin, chemotherapy, number of postoperative antibiotics, and length of bone resection were not associated with infection. Subclass analysis in femur cases identified a correlation between infection and the extent of partial resection of the quadriceps muscle (P = 0.04). In the multivariate analysis, surface infection represented an independent risk factor for deep infection (P = 0.03). Deep infection was a risk for endoprosthesis survival (P = 0.003) but did not affect the oncological outcome.

CONCLUSIONS

A strong correlation between the condition of soft tissue and establishment of deep infection is suggested in this study. Although practical options for preventing deep infection seem limited, the present data allow a form of perioperative evaluation for patients with a higher risk of deep infection.

[Effects of SERMs on bone health. The evaluation of raloxifene treatment for elderly women with osteoporosis using bone turnover markers]

The therapeutic effect of Raloxifene (RLX) on bone turnover markers was investigated in the elderly women with osteoporosis. The mean age of the control group (< 75 years old) was 67.0 years old, similar to a large-scale clinical trial (MORE study) , and that of the elderly group ( > or =years old) was 80.7 years old. The degrees of percentage change from baseline of serum NTX, urine NTX, and BAP in the elderly group were the same as in the control group. The interval of measurement to assess the effect of RLX seems to be appropriate 3 months after treatment in serum and urine NTX, and 6 months in BAP.

Continuous decompression using a cannulated ceramic pin for simple bone cysts

PURPOSE

To report the outcomes of continuous decompression using a cannulated ceramic pin for simple bone cysts (SBCs).

METHODS

Seven boys and 3 girls aged 7 to 16 (mean, 11) years with SBCs underwent curettage and continuous decompression using a cannulated ceramic pin. The pin was made of hydroxyapatite and tricalcium phosphate. The clinical course, radiological findings, and complications were retrospectively assessed.

RESULTS

The mean follow-up duration was 41 (range, 12-84) months. Five patients were evaluated as 'healed', 2 as 'healing with defect', one as 'persistent cyst', and 2 as 'recurrent cysts'. No peri-operative complications were encountered. One patient had a postoperative fracture at the pin insertion site. Seven patients had pain relief and good outcomes; 2 had a thin cortical rim and complained of occasional pain and their sports activities were restricted.

CONCLUSION

Decompression using a cannulated ceramic pin for SBCs is minimally invasive, highly osteoconductive, and does not require bone grafting or a second operation to remove the device.

Occult myofibroblastic sarcoma detected on FDG-PET performed for cancer screening

We present a rare case of occult low-grade myofibroblastic sarcoma (LGMFS) detected by marked 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) uptake on positron emission tomography (PET). A 46-year-old woman presented with abnormal FDG uptake in her back when FDG-PET was performed for cancer screening. The maximum standard uptake values (SUVmax) were 9.8. Physical examination and laboratory investigations revealed no abnormalities. Magnetic resonance images demonstrated an ill-defined 2 x 3 cm mass in the multifidus muscle. Excisional biopsy led to a pathological diagnosis of LGMFS. Additional wide resection was performed for local control. No local recurrence or distant metastasis was observed 12 months after the initial operation. This is the first report describing FDG-PET findings of LGMFS, suggesting a discrepancy between histological grade and SUV intensity in this low-grade entity.

Perioperative d-dimer levels in patients with musculoskeletal tumors

BACKGROUND

D-dimer (DD) levels have been reported as a sensitive but non-specific indicator for deep vein thrombosis (DVT) and pulmonary embolism (PE). Few reports have examined perioperative DD levels in musculoskeletal tumor.

MATERIALS/METHODS

Subjects comprised 77 patients who had undergone oncological resection of musculoskeletal tumor. DD levels were assessed preoperatively and on postoperative days 1 and 7. Multidetector-row computed tomography (MD-CT) was performed to detect DVT/PE for cases with DD level >10.0 microg/ml.

RESULTS

Mean preoperative DD level was 0.84 microg/ml. Significant elevation of postoperative DD levels was confirmed. DD levels were significantly changed by various clinical conditions, such as malignancy, age and prosthetic reconstruction. In 4 of 5 cases with postoperative DD levels >10.0 microg/ml, DVT/PE was detected.

CONCLUSION

Activation of the coagulation system by surgery and heterogeneity of DD levels under various clinical conditions in musculoskeletal tumor patients were suggested.

Development of a clinical diagnosis support tool to identify patients with lumbar spinal stenosis

No clinical diagnostic support tool can help identify patients with LSS. Simple diagnostic tool may improve the accuracy of the diagnosis of LSS. The aim of this study was to develop a simple clinical diagnostic tool that may help physicians to diagnose LSS in patients with lower leg symptoms. Patients with pain or numbness of the lower legs were prospectively enrolled. The diagnosis of LSS by experienced orthopedic specialists was the outcome measure. Multivariable logistic regression analysis identified factors that predicted LSS; a simple clinical prediction rule was developed by assigning a risk score to each item based on the estimated beta-coefficients. From December 2002 to December 2004, 104 orthopedic physicians from 22 clinics and 50 hospitals evaluated 468 patients. Two items of physical examination, three items of patients' symptom, and five items of physical examination were included in the final scoring system as a result of multiple logistic regression analysis. The sum of the risk scores for each patient ranged from -2 to 16. The Hosmer-Lemeshow statistic was 11.30 (P = 0.1851); the area under the ROC curve was 0.918. The clinical diagnostic support tool had a sensitivity of 92.8% and a specificity of 72.0%. The prevalence of LSS was 6.3% in the bottom quartile of the risk score (-2 to 5) and 99.0% in the top quartile (12 to 16). We developed a simple clinical diagnostic support tool to identify patients with LSS. Further studies are needed to validate this tool in primary care settings.