Can decompression surgery relieve low back pain in patients with lumbar spinal stenosis combined with degenerative lumbar scoliosis?

Introduction

Decompression with fusion is usually recommended in patients with lumbar spinal stenosis (LSS) combined with degenerative lumbar scoliosis (DLS). However, elderly patients with LSS and DLS often have other comorbidities, and surgical treatment must be both safe and effective. The aim of this study was to investigate whether decompression surgery alone alleviates low back pain (LBP) in patients with LSS and DLS, and to identify the predictors of postoperative residual LBP.

Materials and methods

A total of 75 patients (33 males and 42 females) with a mean age of 71.8 years (range 53–86 years) who underwent decompression surgery for LSS with DLS (Cobb angle ≥ 10°) and had a minimum follow-up period of 1 year, were retrospectively reviewed using the Japanese Orthopaedic Association scoring system for the assessment of lumbar spinal diseases (JOA score). Radiographic measurements included coronal and sagittal Cobb angles, apical vertebral rotation (Nash-Moe method), and anteroposterior and lateral spondylolisthesis. Logistic regression analysis was performed to investigate the predictors of residual LBP after surgery.

Results

Forty-nine patients had preoperative LBP, of which 29 (59.1 %) experienced postoperative relief of LBP. Logistic regression analysis demonstrated that the degree of apical vertebral rotation on preoperative radiography was significantly associated with postoperative residual LBP (odds ratio, 8.16, 95 % confidence interval, 1.55–83.81, p = 0.011).

Conclusion

A higher degree of apical vertebral rotation may therefore be an indicator of mechanical LBP in patients with LSS and DLS. Decompression with fusion should be recommended in these patients.     

Lateral radiography of the knee with single-leg standing

The purpose of this investigation was to accomplish reproducible radiography of single-leg standing lateral radiography of the knee by adjusting lateral rotation using a ruler to measure foot position. After preliminary assessment of three-dimensional CT of the knees of normal volunteers, the best adjustment of external rotation was estimated. A ruler was made for use in adjusting the angle of knee rotation by measuring foot rotation. Based on the foot rotation measured by this ruler, the positioning of radiography was adjusted to correct rotation. Rotation was estimated by the distance between the posterior edges of the lateral and medial femoral condyles. Fifteen-degree and 17.5-degree rotations were used for correction. Correction of rotation was 17 degrees on average. This helped not only to correct external rotation in the initial radiography but also to correct rotation for repeat radiography. Our method is quantitative and highly reproducible, and it increases the success rate of lateral knee radiography.     

Detection of lung nodules on digital chest radiographs: potential usefulness of a new contralateral subtraction technique

PURPOSE: To evaluate the potential usefulness of a contralateral subtraction technique developed for radiologists' performance in the detection of subtle lung nodules on chest radiographs. MATERIALS AND METHODS: Fifty chest radiographs (25 normal and 25 abnormal with a subtle lung nodule) that were digitized with a 0.175-mm pixel size and 4,096 gray levels were used. Twelve radiologists (10 attending and two residents) participated in observer tests and read both original and contralateral subtraction images with a sequential testing method. Radiologists' performance was evaluated by means of receiver operating characteristic analysis with use of a continuous rating scale. The beneficial and detrimental effects of the contralateral subtraction technique on the radiologists' performance were also evaluated. RESULTS: The area under the receiver operating characteristic curve values obtained without and with contralateral subtraction images were 0.926 and 0.962, respectively. Results indicated that the contralateral subtraction images significantly (P <.05) improved diagnostic accuracy, particularly for radiologists with limited experience. CONCLUSION: The contralateral subtraction technique can assist radiologists in the correct identification of subtle lung nodules on chest radiographs.     

Surgical site infection in living-donor liver transplant recipients: a prospective study

BACKGROUND: Infection is a constant threat for the living-donor liver transplantation (LDLT) recipients, although little information is available on the occurrence of infection in such patients. METHODS: One hundred and thirteen consecutive LDLT recipients were prospectively followed for the presence of surgical site infections (SSIs) defined by CDC from April 2001 to March 2002. Risk factors for SSIs were evaluated by univariate and multivariate analysis. RESULTS: Of the 113 LDLT recipients, 42 (37%) developed 57 episodes of SSIs (21 intraabdominal abscess, 20 peritonitis, 8 cholangitis, and 9 wound). Of the 57 episodes, 29 (51%) had secondary bacteremia in 19 patients. Causative pathogens, including 17 episodes of polymicrobial infections, were 37 gram-positive cocci (17 Staphylococcus aureus, 16 Enterococcus spp., and 4 others), 40 gram-negative rods (25 Enterobacteriaceae, 13 Pseudomonas aeruginosa, and 4 others), and 2 Candida albicans. Univariate analysis revealed that ABO incompatibility and repeat surgery were associated with the development of SSIs. Also, univariate analysis revealed that adult recipients, ABO incompatibility, total operation duration, repeat surgery, and NNIS risk index were associated with secondary bacteremia. Multivariate analysis revealed that ABO incompatibility (OR: 14.0; 95% CI, 2.52-77.2) and repeat surgery (OR: 9.29; 95% CI, 2.00-43.1) were independently associated with secondary bacteremia. Eleven of the 42 cases (26%) who developed SSIs died. Of these 11 cases, 5 (45%) developed secondary bacteremia within 30 days before death. CONCLUSION: SSIs occurred in 37% of LDLT recipients. ABO incompatibility and repeat surgery increased the risk of developing SSIs with secondary bacteremia, which correlated with poor prognosis.     

Regeneration of defects in articular cartilage in rat knee joints by CCN2 (connective tissue growth factor).

CTGF/CCN2, a hypertrophic chondrocyte-specific gene product, possessed the ability to repair damaged articular cartilage in two animal models, which were experimental osteoarthritis and full-thickness defects of articular cartilage. These findings suggest that CTGF/CCN2 may be useful in regeneration of articular cartilage. INTRODUCTION: Connective tissue growth factor (CTGF)/CCN2 is a unique growth factor that stimulates the proliferation and differentiation, but not hypertrophy, of articular chondrocytes in vitro. The objective of this study was to investigate the therapeutic use of CTGF/CCN2. MATERIALS AND METHODS: The effects of recombinant CTGF/CCN2 (rCTGF/CCN2) on repair of damaged cartilage were evaluated by using both the monoiodoacetic acid (MIA)-induced experimental rat osteoarthritis (OA) model and full-thickness defects of rat articular cartilage in vivo. RESULTS: In the MIA-induced OA model, quantitative real-time RT-PCR assays showed a significant increase in the level of CTGF/CCN2 mRNA, and immunohistochemical analysis and in situ hybridization revealed that the clustered chondrocytes, in which clustering indicates an attempt to repair the damaged cartilage, produced CTGF/CCN2. Therefore, CTGF/CCN2 was suspected to play critical roles in cartilage repair. In fact, a single injection of rCTGF/CCN2 incorporated in gelatin hydrogel (rCTGF/CCN2-hydrogel) into the joint cavity of MIA-induced OA model rats repaired their articular cartilage to the extent that it became histologically similar to normal articular cartilage. Next, to examine the effect of rCTGF/CCN2 on the repair of articular cartilage, we created defects (2 mm in diameter) on the surface of articular cartilage in situ and implanted rCTGF/CCN2-hydrogel or PBS-hydrogel therein with collagen sponge. In the group implanted with rCTGF/CCN2-hydrogel collagen, new cartilage filled the defect 4 weeks postoperatively. In contrast, only soft tissue repair occurred when the PBS-hydrogel collagen was implanted. Consistent with these in vivo effects, rCTGF/CCN2 enhanced type II collagen and aggrecan mRNA expression in mouse bone marrow-derived stromal cells and induced chondrogenesis in vitro. CONCLUSION: These findings suggest the utility of CTGF/CCN2 in the regeneration of articular cartilage.     

Simultaneous hepatic artery and portal vein thrombosis after living donor liver transplantation

Simultaneous hepatic artery and portal vein thrombosis rarely occurs after liver transplantation. The etiology is unknown. Of 213 patients (72 children and 141 adults) that underwent living donor liver transplantation (LDLT) from January 1996 to March 2003, 4 (2%) developed simultaneous thrombosis at 3 hours to 7 days (median, 4 days) after the operation. Emergent thrombectomy was performed in three patients; the remaining patient was registered in the Japan organ transplant network. All of the patients died due to hepatic failure (range, 18 hours to 6 days after the diagnosis; median, 2 days). Portal vein, hepatic artery, and hepatic vein velocity in the liver graft were measured every 12 hours by Doppler ultrasonography for 2 weeks after liver transplantation. These parameters were stable until just before the simultaneous thrombosis. These findings indicate that protocol Doppler ultrasonography can diagnose, but not predict, this fatal complication.     

Comparison of Near-Infrared Spectroscopy and Laser Doppler Flowmetry for Detecting Decreased Hepatic Inflow in the Porcine Liver

Hepatic artery and portal vein thrombosis are devastating complications of partial liver transplantation. Early detection of inflow complications is important, as re-reconstruction can salvage the graft. Near-infrared spectroscopy or laser Doppler flowmetry can be used to detect tissue oxygenation or microcirculation on the liver surface. The aim of this study was to examine which of these two methods better detects changes in hepatic inflow. Sangen-strain pigs (n = 5) were used. The tips of the near-infrared spectroscopy and laser Doppler flowmetry probes were placed separately on the surface of the right liver. Inflow to the liver was controlled during the following seven conditions: control (not clamped), half- and totally clamped portal vein, half- and totally clamped hepatic artery, and half- and totally clamped portal vein and artery. Tissue blood flow was calculated using laser Doppler flowmetry. Oxyhemoglobin, deoxyhemoglobin, and the tissue oxygenation index were measured and calculated using a near-infrared spectroscopy system. The tissue blood flow and oxygenation index could not be used to differentiate between the half-clamped portal vein, half-clamped hepatic artery, and totally clamped portal vein conditions. The oxyhemoglobin minus deoxyhemoglobin value was significantly decreased after half or total clamping of the portal vein or hepatic artery (p <. 001 for each condition). The findings of the present study indicate that near-infrared spectroscopy was more sensitive than Doppler flowmetry for detecting changes in hepatic tissue inflow from the liver surface.     

In situ imaging of the autonomous intracellular Ca(2+) oscillations of osteoblasts and osteocytes in bone

Bone cells form a complex three-dimensional network consisting of osteoblasts and osteocytes embedded in a mineralized extracellular matrix. Ca(2+) acts as a ubiquitous secondary messenger in various physiological cellular processes and transduces numerous signals to the cell interior and between cells. However, the intracellular Ca(2+) dynamics of bone cells have not been evaluated in living bone. In the present study, we developed a novel ex-vivo live Ca(2+) imaging system that allows the dynamic intracellular Ca(2+) concentration ([Ca(2+)](i)) responses of intact chick calvaria explants to be observed without damaging the bone network. Our live imaging analysis revealed for the first time that both osteoblasts and osteocytes display repetitive and autonomic [Ca(2+)](i) oscillations ex vivo. Thapsigargin, an inhibitor of the endoplasmic reticulum that induces the emptying of intracellular Ca(2+) stores, abolished these [Ca(2+)](i) responses in both osteoblasts and osteocytes, indicating that Ca(2+) release from intracellular stores plays a key role in the [Ca(2+)](i) oscillations of these bone cells in intact bone explants. Another possible [Ca(2+)](i) transient system to be considered is gap junctional communication through which Ca(2+) and other messenger molecules move, at least in part, across cell-cell junctions; therefore, we also investigated the role of gap junctions in the maintenance of the autonomic [Ca(2+)](i) oscillations observed in the intact bone. Treatment with three distinct gap junction inhibitors, 18α-glycyrrhetinic acid, oleamide, and octanol, significantly reduced the proportion of responsive osteocytes, indicating that gap junctions are important for the maintenance of [Ca(2+)](i) oscillations in osteocytes, but less in osteoblasts. Taken together, we found that the bone cells in intact bone explants showed autonomous [Ca(2+)](i) oscillations that required the release of intracellular Ca(2+) stores. In addition, osteocytes specifically modulated these oscillations via cell-cell communication through gap junctions, which maintains the observed [Ca(2+)](i) oscillations of bone cells.     

New hepatic vein reconstruction in left liver graft.

The incidence of hepatic venous stenosis is higher in partial liver transplantation. New methods for hepatic venous reconstruction in left liver transplantation, which secure wide anastomosis, were devised and are reported here. In the graft, the right side of the middle hepatic vein or the left side of the left hepatic vein was cut longitudinally and a rectangular-shaped vein patch was attached for venoplasty. In the recipient, after the left and middle hepatic veins were joined, the right side of the middle hepatic vein was cut toward the closed right hepatic vein, making a horizontal cavotomy for anastomosis. Of 92 patients who underwent conventional hepatic vein reconstruction, 3 were complicated by hepatic venous stenosis (median follow-up 43 months). By contrast, there were no hepatic vein complications in the 20 patients who underwent the new technique (7 months). The current method appears to be technically feasible for outflow reconstruction in left liver graft transplantation.