Beneficial effect of risedronate for preventing recurrent hip fracture in the elderly Japanese women

SUMMARY

A 36-month observational study compared the incidence of unaffected side hip fracture in Japanese female osteoporosis patients with a history of hip fracture between 173 patients receiving risedronate and 356 risedronate-untreated controls. New hip fractures were significantly less frequent in the risedronate group, suggesting a preventive effect in high-risk patients.

INTRODUCTION

The purpose of this study was to investigate the preventive effect of risedronate on second hip fracture immediately following a first hip fracture in Japanese female osteoporosis patients with unilateral hip fracture.

METHODS

We conducted a prospective matched cohort study in 184 patients treated with risedronate and 445 patients not receiving risedronate after discharge from hospital. Both groups were followed-up for 36 months, and the incidence of unaffected side hip fracture and the frequency of adverse events were assessed.

RESULTS

Efficacy could be investigated in 173 patients from the risedronate group and 356 patients from the control group. Hip fracture was detected in 5 and 32 patients, respectively. Kaplan-Meier estimates of the 36-month fracture incidence were 4.3% in the risedronate group and 13.1% in the control group (P = 0.010, log-rank test). The hazard ratios (95% confidence intervals) obtained by univariate and multivariate analysis were 0.310 (0.121-0.796) and 0.218 (0.074-0.639), respectively, indicating a significantly lower incidence of unaffected side hip fracture in the risedronate group. Adverse events occurred in 38 patients (48 events) from the risedronate group and 94 patients (108 events) from the control group, with serious adverse events in 21 patients (26 events) and 78 patients (88 events), respectively.

CONCLUSIONS

No significant differences were observed between the two groups. The incidence of unaffected side hip fracture was significantly lower in the risedronate group. Accordingly, risedronate may have a preventive effect on hip fracture in high-risk Japanese female osteoporosis patients for fracture with a history of unilateral hip fracture.

Osteoporotic changes of subchondral trabecular bone in osteoarthritis of the knee: a 3-T MRI study

SUMMARY

Subchondral trabecular bone structure was analyzed in knee osteoarthritis (OA) patients using 3-T MRI to investigate structural features of subchondral trabecular bone of knee OA. With OA progression, osteoporotic changes were observed in the lateral joint, showing a higher correlation than sclerotic changes in the medial joint.

INTRODUCTION

To investigate structural features of subchondral trabecular bone of knee osteoarthritis (OA).

METHODS

Sixty knees with KL grade 0-4 (all female) were examined. Fast imaging employing steady-state acquisition-cycled phases (FIESTA-c) and FatSat Spoiled gradient recalled acquisition in the steady state (SPGR) images were acquired by 3-T MRI. At four sites (the medial femur, medial tibia, lateral femur, and lateral tibia), subchondral trabecular bone structure was analyzed by FIESTA-c imaging, cartilage area was measured by SPGR imaging, and their correlation was analyzed. In addition, the subjects were classified into four groups from the cartilage area measured by SPGR imaging, and subchondral trabecular bone structure in each group was compared.

RESULTS

As cartilage area decreased in the medial joint, bone volume fraction and trabecular thickness in the medial tibia increased, and bone volume fraction, trabecular thickness, number, and connectivity in the lateral femur and lateral tibia decreased (r ≥ 0.4 or ≤-0.4, p ≤ 0.001). Compared to medially, the changes laterally showed a higher correlation. When the medial-lateral ratio of trabecular thickness in the tibia was determined, it had the highest correlation coefficient (r=-0.7, p < 0.001). These changes were not significantly detected in the early stage.

CONCLUSIONS

To more sensitively detect OA changes in subchondral trabecular bone structure, a focus on osteoporotic changes in the lateral joint and the medial-lateral ratio would be useful. Detectability of early OA remains unknown, but based on a strong correlation with the degree of OA progression, trabecular structural analysis of subchondral bone may be a useful parameter to evaluate OA severity and evaluate treatment.

Improvement of a compressed inferior vena cava due to IgG4-related retroperitoneal fibrosis with steroid therapy

A 79-year-old man had a 3.5-year history of edema of the lower extremities of unknown etiology. Abdominal computed tomography showed a soft tissue mass around the abdominal aorta, and the biopsy revealed dense fibrosis with abundant infiltration of IgG4-positive plasma cells. His serum IgG4 level was increased to 188 mg/dL. His lower extremity edema was induced by stenosis of the inferior vena cava (IVC) due to the mass. With a diagnosis of IgG4-related retroperitoneal fibrosis, he was treated with steroid, and the leg edema decreased with improvement of patency of the IVC and reduction of the soft tissue mass.

In vivo structural analysis of subchondral trabecular bone in osteoarthritis of the hip using multi-detector row CT

OBJECTIVE

With developments in clinical computed tomography (CT), in vivo analysis of patients' bone microstructure has become increasingly possible. We analyzed the subchondral trabecular bone of hip osteoarthritis (OA) patients using multi-detector row CT (MDCT) to closely examine the structural changes that occur as OA progresses.

DESIGN

47 female hip joints were studied: 20 with OA secondary to hip dysplasia (11 advanced OA, nine early-moderate OA), seven with hip dysplasia without OA, and 20 normal. The images' maximal spatial resolution was 280 × 280 × 500 μm. Regions of interest (ROIs) were the subchondral trabecular bones of the acetabulum and femoral head. Measurement parameters were bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), structure model index (SMI), trabecular bone pattern factor (TBPf), Euler's number, and degree of anisotropy (DA). Relationships between joint space volume and these parameters were analyzed.

RESULTS

With decreasing joint space, Tb.Th and BV/TV increased, and Tb.Sp, Tb.N, SMI, TBPf, and DA decreased significantly. The microstructures were significantly different between the early to advanced OA groups and the normal and dysplasia groups; there was no significant difference between the normal and dysplasia groups.

CONCLUSIONS

Changes of subchondral trabecular bone structure in OA could be evaluated using MDCT, despite imperfect spatial resolution and limited accuracy. Trabecular bone thickening and associated structural changes may be closely related to OA. Changes were observed in early to advanced OA, but not in dysplasia. This method may help to further elucidate OA pathogenesis, determine the therapeutic strategy, and evaluate therapy.

GRIP1 enhances estrogen receptor alpha-dependent extracellular matrix gene expression in chondrogenic cells

OBJECTIVE

The role of postmenopause on the pathogenesis of cartilage degeneration has been an open question. We assessed cartilage degeneration in estrogen receptor (ER)alpha null mice and examined the role of glucocorticoid receptor-interacting protein 1 (GRIP1) in the ERalpha-dependent transcription of a type II collagen gene (col2a1) with special reference to a crosstalk with the transforming growth factor (TGF)-beta signaling pathway.

METHODS

The vertebral cartilaginous endplate from female ERalpha null mice was subjected to histological analyses. Col2a1 expression of primary chondrocytes (PCs) obtained from ERalpha null mice after 17beta-estradiol (E(2)) and TGF-beta1 stimulation was examined by reverse transcription polymerase chain reaction (RT-PCR). Estrogen response element (ERE) or col2a1 promoter-enhancer luciferase reporter system was used to investigate the crosstalk among ERalpha, GRIP1, and MKK6. Col2a1 expression and glycosaminoglycan (GAG) content were measured in ATDC5 cells treated with GRIP1 small interfering RNA (siRNA).

RESULTS

ERalpha deficiency clearly accelerated impairment of the vertebral cartilaginous endplate. E(2) and TGF-beta1 stimulation increased col2a1 expression in PC from wild-type mice, but not that from ERalpha null mice. The same stimulation increased the col2a1 promoter-enhancer reporter activity, and the elevated activity was decreased by dominant-negative ERalpha and p38 mitogen-activated protein kinase (MAPK) inhibitor. GRIP1 increased the E(2)-dependent ERE activation in the presence of ERalpha and constitutive-active MKK6. GRIP1 siRNA repressed col2a1 expression and GAG production in ATDC5 cells.

CONCLUSIONS

Crosstalks between ERalpha/GRIP1 and TGF-beta/MKK6/p38 MAPK pathway have protective roles on cartilage metabolism via regulating the extracellular matrices expression. The finding may lead to the development of a novel therapeutic approach for cartilage degeneration.

Microendoscopic resection of lumbar discal cysts

INTRODUCTION

A lumbar discal cyst is a relatively rare cystic lesion that communicates with lumbar intervertebral discs. Surgical resection of the cyst is the reported treatment of choice. In this study, the authors report the minimally invasive surgical resection of lumbar discal cysts using a microendoscopy.

PATIENTS AND METHODS

Seven male patients with lumbar discal cysts underwent microendoscopic resections (mean age: 25.1+/-3.2 years and the mean follow-up period: 27.9 months). During the surgeries, the cysts were subtotally resected in a piecemeal fashion, and the fistulas forming the communications between the cysts and the corresponding intervertebral discs were coagulated using a bipolar coagulator.

RESULTS

All the patients obtained relief from their pain after surgery, and no recurrences occurred during a mean follow-up period of 28 months. The mean operation time was 72.6+/-20.2 min, and the mean blood loss was 44.4+/-13.7 grams. No intra- or peri-operative complications were noted in any of the patients.

CONCLUSIONS

Microendoscopic resection appears to be a minimally invasive and feasible surgical option for the treatment of lumbar discal cysts.

Anterior screw fixation for odontoid fracture: clinical results in 45 cases

Clinical results of anterior screw fixation in 45 patients with odontoid fractures were reviewed retrospectively. The patients were 36 males and 9 females, with fractures classified as 35 type II and 10 type III. There were 34 fresh and 11 old fractures. Neurological complications were present in 16 patients and 18 had associated injuries. All patients underwent single screw fixation. Postoperative immobilization, external support, and surgical trauma were minimal. In one patient a screw extruded from the dens and immediate posterior fusion was necessary. The overall rate of fracture union was 93% (41 out of 44 fractures). Fracture resolution averaged 5.2 months. There were two delayed unions and three nonunions, the causes of which were preoperatively established nonunion, severe osteoporosis, and inaccurate screw placement. Out of 11 old cases, 8 went on to union. Ninety-six percent of the patients recovered neurologically. The overall complication rate, including a misplaced screw, a retropharyngeal wall injury, and three nonunions, was 11%. Head rotation was preserved in 90% of the patients with fracture union according to clinical measurements. Anterior screw fixation is an excellent treatment for fresh type II and cephalad type III odontoid fractures, carrying a high union rate, preservation of the C1-2 motion segment, and minimal surgical trauma; it can be applied even to some old cases. Precise patient selection in regard to patient age, bone density, and time elapsed since injury as well as preoperative anatomical reduction and meticulous surgical technique with fine fluoroscopy are essential to avoid complications and nonunions.

[Paraplegia associated with acute aortic dissection complicated with pulmonary embolism and re-dissection]

Paraplegia associated with acute aortic dissection is one of the most serious complications. We experienced a case of Stanford type A acute aortic dissection with paraplegia and cardiac tamponade because the dissection was already thrombosed, conservative therapy was chosen. After drainage of pericardial effusion, a spinal drainage tube was inserted. Eleven days later, pulmonary embolism and re-dissection occurred, and an emergency operation was performed. Although the operation was successful, paraplegia did not improve. Even if type A acute aortic dissection is complicated with paraplegia, early surgical repair of aortic dissection should be considered, when paraplegia does not improve rapidly in spite of treatment.

Discovery of a potent, metabolically stabilized resorcylic lactone as an anti-inflammatory lead

With bioactivity-guided phenotype screenings, a potent anti-inflammatory compound f152A1 has been isolated, characterized and identified as the known natural product LL-Z1640-2. Metabolic instability precluded its use for the study on animal disease models. Via total synthesis, a potent, metabolically stabilized analog ER-803064 has been created; addition of the (S)-Me group at C4 onto f152A1 has resulted in a dramatic improvement on its metabolic stability, while preserving the anti-inflammatory activities.

[Ruptured aneurysm of the sinus of Valsalva with severe liver dysfunction; report of a case]

The patient is a 59-year-old male who complained of acute palpitation, shivering and chest oppression. His laboratory data showed severe liver dysfunction (AST 3,445 IU/l, ALT 2,937 IU/l, and LDH 3,200 IU/l). By echocardiography, abnormal shunt flow was detected in the right atrium, and it was diagnosed as a ruptured aneurysm of the Valsalva sinus (Konno type IV). Suture closure of the fistula was performed from the right atrial side, and then, patch closure was performed from the aortic side with auto-pericardium to cover the whole non-coronary sinus, which was heavily calcified. The liver function rapidly restored to a normal range postoperatively. In a case of severe liver dysfunction, such cardiac disease should also be considered.

Microendoscopic discectomy for lumbar disc herniation with bony fragment due to apophyseal separation

The purpose of this study was to elucidate the feasibility of microendoscopic discectomy (MED) for the treatment of lumbar disc herniation with a bony fragment due to apophyseal separation. Eighteen patients with low back pain and unilateral sciatic pain due to lumbar disc herniation with a bony fragment were treated by MED using the unilateral approach (15 males and three females; mean age, of 28.9 years; mean follow-up period, 21.1 months); 18 age-and sex-matched patients with lumbar disc herniation without a bony fragment treated by MED served as the control group. The clinical outcomes were evaluated using the Japanese Orthopedic Association Score for Low Back Pain (JOA scores; maximum score, 29 points). Evaluation of the results revealed that good surgical outcomes equivalent to those in the control group were obtained in the subjects of LDH with a bony fragment (JOA scores; 14.1+/-3.5 in the patient group vs.15.4+/-2.6 in the control group before surgery; 26.3+/-1.8 in the patient group vs. 26.9+/-1.3 at follow-up after the surgery). Although the mean surgical time was significantly longer in the patient group, there were no intra- or postoperative complications in either group. We conclude that MED using the unilateral approach is a feasible minimally invasive surgical option for patients of lumbar disc herniation with an apophyseal bony fragment.

Surgical treatment of intramedullary spinal cord tumors: prognosis and complications

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To evaluate our recent treatment strategy for intramedullary spinal cord tumors.

SETTING

Department of Orthopaedic Surgery, Keio University, Japan.

METHODS

We reviewed 68 cases of intramedullary tumors (ependymoma, 33; astrocytoma, 23; hemangioblastoma, 12), treated surgically between 1994 and 2003. There were 42 males and 26 females whose mean age at the time of surgery was 43 years. The mean follow-up period was 6.2 years. The tumor malignancy grade according to the WHO classification was astrocytoma grade I, 3; grade II, 8 (low-grade: 11 cases); grade III, 10; grade IV, 2 (high-grade: 12 cases). All ependymomas were grade II. Three of the 12 hemangioblastomas were associated with von Hippel-Lindau disease.

RESULTS

Total excision was achieved in 90% of the ependymomas and functional improvement was obtained when the preoperative neurological deficit was mild. Approximately 50% of low-grade astrocytomas could be totally excised with favorable survival outcomes, suggesting that total excision should be attempted for low-grade astrocytomas. However, total excision of high-grade tumors was difficult and the functional outcomes were poor. Cordotomy should be considered in patients with a thoracic high-grade astrocytoma. Total resection was possible in 92% of hemangioblastoma, and the functional outcomes were good, however, more attention should be paid for tumors with feeding arteries on the ventral side and for those associated with von Hippel-Lindau disease.

CONCLUSIONS

Predictors of good surgical outcome for intramedullary spinal cord tumors were histological grades of the tumors, surgical margins, and neurological status of the patient before surgery.

134 CONCEPTION RATES OF IN VITRO-PRODUCED BOVINE EMBRYOS CRYOPRESERVED IN 6% GLYCEROL AND TRANSFERRED BY THE DIRECT METHOD

Ethylene glycol has been used as the standard cryoprotectant for direct transfer of bovine embryos due to its high permeability. But Merton et al. reported that cryoprotectivity of glycerol for bovine embryos was superior to that of ethylene glycol (2001 Theriogenology 55, 312 abst). We previously reported that nonsurgical transfer of in vivo-derived bovine embryos cryopreserved in a lower concentration (5%) of glycerol and thawed by stepwise method resulted in a 55.4% conception rate, whereas direct transfer without removal of cryoprotectant showed only a 45.1% conception rate (Takada et al. 2005 Jpn. J. Embryo Transfer 27, 59–64). In this experiment, survival and conception rates of in vitro-produced (IVP) bovine embryos cryopreserved in 6% glycerol solution (GLY) were compared to those of embryos cryopreserved in 10% ethylene glycol plus 0.1 M sucrose solution (EG). Cumulus–oocyte complexes were matured and fertilized according to Numabe et al. (2000 Theriogenology 54, 1409–1420). Presumed zygotes were cultured in mSOF supplemented with 5% calf serum (CS) and 0.25% linoleic acid albumin at 38.5�C under 5% CO2, 5% O2, 90% N2 for 7 days. At the expanded blastocyst stage, embryos were placed in GLY or EG in PBS supplemented with 20% CS for 15 min at room temperature and loaded into 0.25-mL straws. Straws were placed directly into an alcohol freezer. When the cryoprotectant was GLY, straws were seeded at -4.0�C, held for 10 min, cooled at 0.5�C min to -30.5�C, and then plunged into liquid nitrogen. When the cryoprotectant was EG, the seeding point was -7.5�C, and the plunging point was -34.0�C, but the rest of the protocol was the same as for GLY. In Exp. 1, thawing in both groups was done in a 30�C water bath, and the contents were directly rehydrated in PBS with 20% CS. Thawed embryos were cultured in mSOF with 5% CS for 24 h to assess embryo survival rate, based on the re-expansion of the blastcoele and on their hatching ability. In Exp. 2, embryos in both groups were thawed and transferred to synchronous recipients without removing the cryoprotectant. Data were analyzed using chi-square analysis. In Exp. 1, the developmental rates of post-thaw embryos were similar in GLY (46/52, 88.5%) and EG (45/52, 86.5%); however, the hatching rate was significantly higher (P &lt; 0.05) in embryos cryopreserved in EG (26/52, 50.0%) than in GLY (15/52, 28.8%). In Exp. 2, the conception rates of embryos were similar in both groups, GLY (7/15, 46.7%) and EG (6/15, 40.0%). In conclusion, after direct rehydration of embryos, the developmental ability of IVP bovine embryos cryopreserved in EG was superior to that of embryos cryopreserved in GLY in vitro. However, conception rates in vivo were similar in both groups. These results suggest that a lower concentration of glycerol might be still useful as a cryoprotectant for direct transfer of IVP bovine embryos.

No proarrhythmic properties of the antibiotics Moxifloxacin or Azithromycin in anaesthetized dogs with chronic-AV block

BACKGROUND & PURPOSE

The therapeutically available quinolone antibiotic moxifloxacin has been used as a positive control for prolonging the QT interval in both clinical and non-clinical studies designed to assess the potential of new drugs to delay cardiac repolarization. Despite moxifloxacin prolonging QT, it has not been shown to cause torsades de pointes arrhythmias (TdP). Azithromycin is a macrolide antibiotic that has rarely been associated, clinically, with cases of proarrhythmia. As there is a lack of clinical data available, the cardiac safety of these drugs was assessed in a TdP-susceptible animal model by evaluating their repolarization and proarrhythmia effects.

EXPERIMENTAL APPROACH & KEY RESULTS

In transfected HEK cells, the IC(50)s for I (hERG) were 45+/-6 and 856+/-259 microg ml(-1) for moxifloxacin and azithromycin, respectively. Intravenous administration of 2 and 8 mg kg(-1) moxifloxacin (total peak-plasma concentrations 4.6+/-1.5 and 22.9+/-6.8 microg ml(-1)) prolonged the QT(c) in 6 anaesthetized dogs with chronic AV block by 7+/-3 and 21+/-19%, respectively. Similar intravenous doses of azithromycin (total peak-plasma concentrations 5.4+/-1.3 and 20.8+/-4.9 microg ml(-1)) had no electrophysiological effects in the same dogs. The reference compound, dofetilide (25 microg kg(-1) i.v.) caused QT(c) prolongation (29+/-15%) and TdP in all dogs. Beat-to-beat variability of repolarization (BVR), quantified as short-term variability of the left ventricular monophasic action potential duration, was only increased after dofetilide (1.8+/-0.7 to 3.8+/-1.5 ms; P<0.05).

CONCLUSION & IMPLICATIONS

As neither moxifloxacin nor azithromycin caused TdP or an increase in the BVR, we conclude that both drugs can be used safely in clinical situations.

Surgical outcomes of spinal cord astrocytomas

STUDY DESIGN

Retrospective case series.

OBJECTIVES

To analyze prognostic factors for patients with spinal cord astrocytomas.

SETTING

Department of Orthopaedic Surgery, Keio University, Japan.

METHODS

Seven patients received total excisions (group T), eight underwent partial excisions (group P), and 15 had excisional biopsies (group B). Impacts of the tumor histological grade, the level of the tumor, the types of surgical interventions, and the use of adjuvant radiotherapies on the survival and functional outcomes of 30 patients (18 in low-grade and 12 high-grade malignancy tumors) were analyzed.

RESULTS

The survival rate of the low-grade malignancy group was significantly higher than that of the high-grade group. The survival rate of the patients with thoracic astrocytomas was significantly higher than those with cervical astrocytomas. In both the low- and high-grade groups, the survival rates in groups P/T were significantly higher than those in group B. In the low-grade group, five patients, whose preoperative functional statuses were classified as 'fair' or better, remained 'fair' or better after surgery. In the high-grade group, the postoperative functional statuses were classified as 'no change' or 'aggravated' in all except two patients. No significant difference in the survival rates was detected between patients with and without adjuvant radiotherapy.

CONCLUSIONS

The tumor grade and the extent of tumor resection were significant prognostic factors for survival rate. In low-grade malignancy group, good motor function was retained when surgeries were performed before substantial neurological deterioration. The efficacy of postoperative radiotherapy has yet to be determined and needs further study.

Deep lamellar keratoplasty by deep parenchyma detachment from the corneal limbs

AIM

To improve the deep lamellar keratoplasty technique.

METHOD

For the easy and reliable perfomance of deep lamellar keratoplasty (DLKP), detachment of Descemet's membrane through the corneal limber flap was improved. To expose Descemet's membrane, the parenchyma was detached by hydrodelamination through a sclerocorneal flap made in the corneal limbs. The parenchyma was removed after the pseudochamber between it and Descemet's membrane was maintained with viscoelastic material. The corneal graft was placed with a running suture. 22 eyes were treated.

RESULTS

Complete exposure of Descemet's membrane was obtained in 20 of the 22 eyes (91%). The membrane was perforated in five of the 22 eyes (23%) during surgery, and two of the 22 eyes (9%) were converted to penetrating keratoplasty. These two eyes developed keratoconus after acute corneal hydrops.

CONCLUSION

Compared with the conventional procedure, this new method provides easy, reliable exposure of Descemet's membrane.

Ischemia-induced disturbance of neuronal network function in the rat spinal cord analyzed by voltage-imaging

Using a voltage-imaging technique, we analyzed the acute effect of ischemia, hypoxia and hypoglycemia on the neuronal network function of the rat spinal cord. Ischemic, hypoxic, or hypoglycemic stress was loaded to spinal cord slices with an oxygen- and glucose-free, oxygen-free, or glucose-free mock cerebrospinal fluid, respectively. Depolarizing signals in the dorsal horn, induced by dorsal root stimulation, consisted of fast (pre-synaptic) and slow (post-synaptic) components. The slow component was attenuated much more than the fast component under an ischemic condition (P<0.0002). Post-synaptic neuronal activities in lamina III-IV were suppressed earlier than those in lamina I-II. The nerve fiber was relatively resistant to ischemia. As long as the fast component was preserved in the dorsal horn, the suppression of the fast and slow components was reversible. There was a significant difference (P<0.05) in the recovered slow component sizes between the group in which the fast component was suppressed by more than 20% by ischemia and the group in which the suppression was less than 20%. Further prolonged stress irreversibly eliminated most of the slow component, and attenuated the fast component (to 59+/-8%) accompanied by cellular damage in histology. Suppression of neural activity by hypoxic or hypoglycemic stress was less prominent than that by ischemia. Prolonged ischemic stress suddenly and irreversibly eliminated depolarizing signals in the ventral horn accompanied by morphological damage of motoneurons. Immunohistochemical staining was negative for apoptosis. We have, for the first time, analyzed the processes of spinal cord disturbance induced by ischemia, hypoxia and hypoglycemia at the neuronal network level by directly observing the regional neuronal network activities within the spinal cord. We conclude that synaptic transmission in the dorsal horn, especially in deep regions, is vulnerable and first affected by these stresses. Severe ischemic stress induces irreversible dysfunction of neurons accompanied by eventual cell death in both dorsal and ventral horns.