Incidence of recreational snowboarding-related spinal injuries over an 11-year period at a ski resort in Niigata, Japan.

BACKGROUND: There is limited knowledge regarding the incidence of recreational snowboarding-related spinal injuries. OBJECTIVE: This study investigated the incidence and characteristics of recent recreational snowboarding-related spinal injuries and discussed possible preventive measures to reduce the risk of spinal injuries. METHODS: This descriptive epidemiological study was conducted to investigate the incidence and characteristics of snowboarding-related spinal injuries at the Myoko ski resort in Niigata Prefecture, Japan, between 2006 and 2017. The incidence of spinal injuries was calculated as the total number of spinal injuries divided by the number of snowboarding visitors, which was estimated based on the ticket sales and estimates regarding the ratio of the number of skiers to the number of snowboarders reported by seven skiing facilities. RESULTS: In total, 124 (72.5%) males and 47 (27.5%) females suffered spinal injuries. The incidence of spinal injuries was 5.1 (95% CI 4.4 to 5.9) per 100 000 snowboarder visitors. Jumps at terrain parks were the most common factor in 113 (66.1%) spinal injuries, regardless of skill level (29/49 beginners, 78/112 intermediates, 6/10 experts). Overall, 11 (including 9 Frankel A) of 14 (78.6%) cases with residual neurologic deficits were involved with jumps. CONCLUSIONS: In recreational snowboarding, jumping is one of the main causes for serious spinal injuries, regardless of skill level. The incidence of spinal injuries has not decreased over time. Individual efforts and educational interventions thus far have proven insufficient to reduce the incidence of spinal injury. Ski resorts and the ski industry should focus on designing fail-safe jump features to minimise the risk of serious spinal injury.

Age at the time of hip fracture in patients with rheumatoid arthritis is 4 years greater than it was 10 years before, but is still younger than that of the general population.

Objective: To investigate the characteristics of hip fractures in patients with rheumatoid arthritis (RA).Methods: Between 2012 and 2015, 789 hip fractures were treated at our hospital. Patients with RA were checked and their characteristics were compared with data recorded 10 years before, and with the general population.Results: There were 11 patients with RA, who were all female, and the mean age was 76 ± 7.0 years. The age at the time of hip fracture was 4 years older than that recorded 10 years before (72 ± 4.5 years, p < .05), but was younger than that of the general population (84 ± 8.0 years, p < .001). The mean prednisolone dose of 2.5 ± 2.6 mg/day was lower than that recorded 10 years before (4.8 ± 2.9 mg/day, p < .05). The rate of patients treated with anti-osteoporotic medications at fracture (73%) was higher than 10 years before (42%); however, the difference was not significant. The incidence of secondary fracture was not high compared to the general population. No mortality was recorded at 1 year, and no infective complications occurred.Conclusion: The age at the time of hip fracture in RA patients is increasing, but is still younger than that of the general population.

Clinical outcome of Niigata-Senami-Kyocera modular unconstrained total elbow arthroplasty for destructive elbow in patients with rheumatoid arthritis.

BACKGROUND: Total elbow arthroplasty (TEA) is a treatment option for destructive and painful unstable elbows in rheumatoid arthritis (RA). We evaluated the clinical outcomes of unconstrained TEA (Niigata-Senami-Kyocera modular system). METHODS: Seventy-five unconstrained TEAs were performed in patients with RA (mean age, 64 years; age range, 41-79 years; follow-up rate, 97%). Outcome measures included the Japanese Orthopaedic Association (JOA) functional evaluation score for the elbow joint (JOA score), range of motion, and arc. Bone ingrowth of the humeral component, the incidence of stress shielding around the humeral component, the incidence of loosening of the ulnar component, complications, and the survival rate were investigated. RESULTS: The mean follow-up period was 5.2 years (range, 2-11.3 years). The JOA elbow score improved from 42 points preoperatively to 87 points postoperatively (P < .0001). Each specified item improved (P < .0001). Flexion improved from 109° to 134°; the flexion-plus-extension arc improved from 70° to 108° (P < .0001). Bone ingrowth of the humeral implant was achieved in all elbows. Stress shielding of the humeral component was detected in 11 elbows (14%); it was significantly higher in 10- and 9-mm-diameter humeral stems than in 8-mm-diameter humeral stems (P = .008). The ulnar component showed no loosening except in 1 elbow owing to infection. Complications were detected in 9 patients (9 elbows, 12%): periprosthetic infection (3), fracture (4), and dislocation (2). The survival rates were 97% at 5 years and 93% at 10 years postoperatively. DISCUSSION: The Niigata-Senami-Kyocera modular system for patients with RA showed good outcomes. Stress shielding can be avoided by using an 8-mm-diameter humeral stem.

Sacral Stress Fracture Complicated by L5 Radiculopathy in a Patient with Rheumatoid Arthritis.

A 60-year-old Japanese woman with severe osteoporosis presented with a history of right buttock pain and right lateral lower leg pain in an L5 distribution. She had been treated with methotrexate and methylprednisolone for rheumatoid arthritis (RA) and interstitial pneumonia. Computed tomography demonstrated a sacral stress fracture in the right sacral ala. The right L5 nerve root was compressed by the fracture site. This case is rare in that L5 radiculopathy was complicated by a sacral stress fracture. Clinicians should suspect sacral stress fractures when RA or osteoporosis is present in women who experiences lumbar pain and lumbar radiculopathy.

Challenges to prevent secondary fractures in patients with hip fractures in Joetsu Myoko, Japan through the increased use of osteoporosis treatment and collaboration with family doctors.

The Niigata Prefectural Central Hospital (NPCH) is one of the main hospitals for the cities of Joetsu and Myoko, Niigata Prefecture, Japan, an area with a population of 240,141, of whom 26.7 % were aged ≥65 years in 2009. In the NPCH, patients with hip fractures are admitted to an orthopedic ward within 4 h, 89.2 % of patients are operated on within 48 h during working hours, and the prevalence of pressure ulcers is 1.5 %. To reduce the incidence of hip fractures, two major challenges emphasizing secondary fracture prevention were initiated in 2012. The first challenge used a team approach-hospital pharmacists asked patients about their drug use histories, orthopedic surgeons began drug therapy for osteoporosis after explaining to patients its importance for the prevention of secondary hip fractures, nurses assessed the risk of falling, and physiotherapists conducted rehabilitation with the aim of preventing falls. The second challenge focused on maintaining treatment for osteoporosis after discharge, when patients were under the oversight of family doctors. The percentages of patients with primary hip fractures who were taking anti-osteoporosis medications at the time of discharge in 2009, 2012, 2013 and 2014 were 21, 33, 41, and 43 %, respectively. The 12-month incidences of hip fractures on the unaffected side in 2009, 2012, 2013 and 2014 were 7.4, 2.2, 0, and 2.4 %, respectively, and the 24-month incidences of such fractures in 2009, 2012 and 2013 were 12, 7.6, and 5.2 %, respectively. Our challenges were effective at decreasing the incidence of secondary fractures.

Bilateral atypical femoral subtrochanteric fractures in a premenopausal patient receiving prolonged bisphosphonate therapy: evidence of severely suppressed bone turnover.

We report a case of bilateral atypical femoral fractures that occurred in a patient who had been taking bisphosphonate long-term. A 36-year-old premenopausal female diagnosed with systemic lupus erythematosus and dermatomyositis had been treated with glucocorticoid and alendronate (5 mg/day) to prevent glucocorticoid-induced osteoporosis. She was taken to our hospital because she could not walk immediately after falling down from the standing position. A plain radiograph showed a subtrochanteric fracture of the left femur. Four months later, she fell again and sustained a contralateral subtrochanteric fracture. For each fracture, a femoral intramedullary nail was inserted. Delayed union was detected in both sides, and revision surgery with an iliac bone graft was required for implant breakage in the right side. Histomorphometric findings for the ilium revealed remarkably decreased osteoid volume with no osteoclasts and a minimally eroded surface, suggesting that bone turnover was severely suppressed. However, histology of the delayed union site revealed callus formation and some osteoclast appearance, suggesting that fracture healing was occurring. In total, it took 29 months (left) and 24 months (right) until fracture healing was achieved, showing delayed union. This case is extremely rare in that patient who presented with atypical femoral fractures in spite of her premenopausal status. The bone histomorphometric findings from this case suggest that severely suppressed bone turnover is associated with atypical femoral subtrochanteric fracture and can cause delayed union in patients treated with alendronate long-term.

Development and validation of a new radiographic scoring system to evaluate bone and cartilage destruction and healing of large joints with rheumatoid arthritis: ARASHI (Assessment of rheumatoid arthritis by scoring of large joint destruction and healing in radiographic imaging) study.

OBJECTIVE: To assess the reliability and sensitivity of a novel scoring method to evaluate the radiographic appearance of and longitudinal changes including joint remodeling in large joints with early and established rheumatoid arthritis (RA). METHODS: The ARASHI study group devised new radiographic scoring systems (Status score; range 0-16 points, and Change score; range -11 to 12 points) for evaluation of large joints with RA. Radiographs showing anterior/posterior views of large joints (shoulder, elbow, hip, knee, and ankle joints) taken at two time points (mean interval 2.3 years) were collected from 25 patients with established RA (5 patients for each of the 5 joints, 50 films in total), and an additional 5 films of each joint with severe joint destruction were collected from 5 different sets of RA patients. After consensus on the definition of each component and reader training, images were evaluated using the Larsen's grading system and the ARASHI Status and Change score by 9 independent senior orthopedic surgeons. The reliability was estimated by intra-class correlation coefficients (ICCs) and measurement error by 95% confidence intervals of minimum detectable change (MDC95). RESULTS: ARASHI Status score and Change score significantly correlated with Larsen's grade (r = 0.89, P < 0.0001) and follow-up-baseline differences in Larsen's grade (r = 0.83, P < 0.0001), respectively. Inter-reader ICCs were very high for both Status score (0.88, 95% confidence interval [CI], 0.83-0.92, P < 0.001) and Change score (0.92, 95% CI, 0.87-0.96, P < 0.001). Intra-reader ICCs were also very high for both Status score (0.92, 95% CI, 0.71-0.98, P < 0.001) and Change score (0.97, 95% CI, 0.91-0.99, P < 0.001). The MDC95 for inter-reader agreement were 4.18 (25% of maximum obtainable score, MOS) and 4.99 (21% of MOS) for Status score and Change score, respectively. The MDC95 for intra-reader agreement was acceptable with 2.82 (17% of MOS) and 3.02 (13% of MOS) for Status score and Change score, respectively. CONCLUSION: The ARASHI scoring method showed good inter-/intra-reader reliability with high ICCs and acceptable MDC95 with respect to each large joint and the components of both Status and Change scores. The results suggest that the ARASHI scoring method might be useful for the assessment of status, as well as longitudinal monitoring of destruction and remodeling of large joints with RA.

Osteoconductive action of alendronate after implantation of beta tricalcium phosphate in rat adjuvant-induced arthritis.

The aim of the study was to determine the effect of alendronate on resorption of ß-tricalcium phosphate (ß-TCP) and bone formation in rats with adjuvant-induced arthritis (AIA). After preparation of a model of AIA in rats (day 0), alendronate or vehicle was injected intraperitoneally once daily five times in a week. Cylindrical ß-TCP was implanted into the rat femoral condyle on day 7. Rats were killed on days 12, 15, and 21, and specimens and serum samples were collected. Specimens were analyzed by tartrate-resistant acid phosphate (TRAP) staining, immunohistochemistry of the ED1 protein, and in situ hybridization with digoxigenin-labeled α1 chain of type I procollagen (COL1A1). Mineralized bone sections were analyzed by Villanueva bone stain. The serum osteocalcin level was measured using an enzyme-linked immunosorbent assay kit. Alendronate decreased the number of TRAP-positive cells attached to ß-TCP, the numbers of ED1-positive multinucleated giant cells, and resorption of ß-TCP. In AIA rats treated with alendronate, COL1A1 mRNA-positive cells adhered to ß-TCP were round or cuboid whereas the cells in untreated AIA rats were fibroblast-like cells. Alendronate increased calcification of newly formed bone whereas it did not restore the bone formation suppressed with inflammation. These results suggest that alendronate has the potential to conduct mature bone after implantation of ß-TCP in AIA. Alendronate may help to reduce insufficiency of newly formed bone after implantation of ß-TCP in diseases characterized by increased bone resorption such as rheumatoid arthritis.

Revision metacarpophalangeal joint replacement 30 years after primary swanson flexible silicone implant arthroplasty in a rheumatoid patient: a case report.

We report a case of a patient with rheumatoid arthritis undergoing revision surgery 30 years after primary metacarpophalangeal joint arthroplasty using a Swanson implant. Removal and replacement of the implant were successfully performed, and the patient was satisfied with the revision surgery.

Tight control is important in patients with rheumatoid arthritis treated with an anti-tumor necrosis factor biological agent: prospective study of 91 cases who used a biological agent for more than 1 year.

The purpose of this study is to identify the factors that require arthroplasty due to the progression of joint destruction, even when an anti-tumor necrosis factor (TNF) biological agent is used for rheumatoid arthritis (RA). Among 91 cases that used the anti-TNF biological agent for more than 1 year, two groups of 21 cases that resulted in arthroplasty (surgery group) and 70 cases that did not result in arthroplasty (non-surgery group) were compared and examined. When the anti-TNF biological agent was first administered, disease activity and internal use of glucocorticoid (PSL) were not different in these two groups. The average DAS28-CRP(4) (disease activity score including a 28-joint count/C-reactive protein) (p < 0.001) and the amount of internal use of PSL (p < 0.05) were significantly decreased in the non-surgery group compared with the surgery group at the final survey. To inhibit the need for joint surgery in patients using the anti-TNF biological agent, it is important to maintain tight control over RA activity.

Proximal femoral fracture in patients with rheumatoid arthritis.

Hip fracture occurrence was examined cross-sectionally in Japanese patients with rheumatoid arthritis (RA). Between January 2005 and June 2006 we studied RA outpatients with a past history of hip fractures. Patients included 1 man and 25 women. As 3 women had bilateral hip fractures, the total number was 29. Age at the time of fracture was 72.1 +/- 4.5 years. Of the 29 fractures, 22 were cervical and 7 were trochanteric. Four fractures were spontaneous while the others occurred in falls. 24 fractures were associated with oral steroid administration. All 5 fractures unassociated with prednisolone were cervical. Of the 26 patients, 8 were taking bisphosphonate when fracture occurred. Cervical fracture was treated with total hip arthroplasty in 1 patient whose hip showed RA changes. In others whose hip joint lacked RA change, procedures included osteosynthesis in 2 patients with good function over 6 years; and hemiarthroplasty with a bipolar system in 19 displaced fractures, with good function over 4.1 years. Osteosynthesis was performed for all 7 trochanteric fractures. Trabeculae were thin, and fewer transverse trabeculae could be found in specimens from cervical fracture. Hip fracture in RA patients occurred 10 years earlier than in the general population, and many fractures were cervical.

High dose glucocorticoid hampers bone formation and resorption after bone marrow ablation in rat.

We analyzed the effect of glucocorticoid on bone regeneration after bone marrow ablation in tibiae of 8-week-old rats. Methylprednisolone sodium succinate (MPSS) was injected intramuscularly at a dose of 100 mg/kg/day for 3 days. Tibiae on days 1, 3, 5, 7, 10, 12, and 14 after ablation were subjected to tartrate-resistant acid phosphatase staining, immunohistochemistry, in situ hybridization, and transmission electron microscopy (TEM), and measurement of the volume of newly-formed bone and the osteoclast number. MPSS significantly decreased the newly-formed bone volume on day 7, and immature bone still remained on day 10 in the MPSS-treated group. The volume of this bone was significantly higher than that in the control group. However, there were no differences between the groups in the osteoclast number, the expression of mRNAs for osteoblast differentiation markers, and alkaline phosphatase and cathepsin K judged by immunohistochemistry. TEM findings showed no difference in the form of osteoblasts, whereas osteoclasts in the MPSS-treated group had less developed ruffled borders, compared to those in the control group. These results suggest that MPSS treatment affects neither the differentiation nor the shape of osteoblasts, and does not change the osteoclast number or the cathepsin K level. However, high dose MPSS inhibits both bone formation and resorption during bone regeneration after rat tibial bone marrow ablation, and inhibits ruffled border formation in osteoclasts. These data will be useful to develop bone regenerative therapies for bone diseases due to high dose steroid administration.

Osteoinduction with highly purified beta-tricalcium phosphate in dog dorsal muscles and the proliferation of osteoclasts before heterotopic bone formation.

The aim of the study was to examine the chronological histology of osteoinduction of highly purified beta-tricalcium phosphate (beta-TCP) implanted in dog dorsal muscles. Specimens were harvested on days 14, 28, 42, 56, 112 and 168 after implantation, and were analyzed by hematoxylin and eosin (HE) staining, tartrate-resistant acid phosphatase (TRAP) staining, immunohistochemistry, in situ hybridization, and silver impregnation. After day 28, abundant TRAP- and cathepsin K-positive multinucleated cells adhered to beta-TCP, suggesting that these cells are osteoclasts that can resorb beta-TCP. On day 56, new bone was formed and alpha1 chain of type I procollagen mRNA-positive osteoblasts lined the newly formed bone. Silver impregnation showed abundant collagen fibrils within the beta-TCP micropores. These results suggest that micropores function as a storage space for extracellular matrix components, including collagen. Newly formed bone never degenerated in the late stage, suggesting that beta-TCP has good biocompatibility and this material retains the conditions appropriate for osteointegration and bioresorption. In conclusion, beta-TCP has osteoinductivity after implantation in dog dorsal muscles without use of bone marrow cells or osteoinductive cytokines. The appearance of a large number of active osteoclasts precedes new bone formation.

Risk factors for vertebral fracture in menopausal or postmenopausal Japanese women with rheumatoid arthritis: a cross-sectional and longitudinal study.

The occurrence of vertebral fracture was examined cross-sectionally and longitudinally over a 4-year interval in 117 menopausal and postmenopausal Japanese women with rheumatoid arthritis (RA), whose ages ranged from 50 to 64 years. Patients treated with bisphosphonate were excluded. Vertebral fracture was diagnosed by lateral thoracic and lumbar spine radiography at the start and end of a 4-year period. Bone mineral density (BMD) at L2-L4 according to dual-energy X-ray absorptiometry (DXA), the administration of corticosteroids or methotrexate, and urinary excretion of N-telopeptide of type I collagen (NTx) were also recorded. In the cross-sectional study, the prevalence of vertebral fracture in the initial radiographs of RA patients was 21%, while it was 5% in healthy age-matched controls. Among RA patients treated with corticosteroids, 33% had vertebral fracture, which was a significantly higher prevalence than that in RA patients without steroid administration. In the longitudinal study, vertebral fracture prevalence was also increased in patients more than 60 years old. RA patients having steroid treatment and a BMD/YAM (young adult mean) ratio below 70% had higher risk of vertebral fracture than patients with a BMD/YAM ratio of 70%-80%, which in turn exceeded the risk with a BMD of 80% or more. No adverse effect of low-dose methotrexate on vertebral fracture was found. Urinary NTx was high in RA patients, as reported previously, and did not differ between patients with or without new fracture after 4 years. In conclusion, Japanese RA patients more than 60 years old who were treated with corticosteroid or had a BMD below 80% had high risk of vertebral fracture.

Bone formation and resorption of highly purified beta-tricalcium phosphate in the rat femoral condyle.

The aim of this study was to examine the chronological histology associated with highly purified beta-tricalcium phosphate (beta-TCP) implanted in the rat femoral condyle. Specimens were harvested on days 4, 7, 14, 28 and 56 after implantation, and were analyzed by tartrate-resistant acid phosphatase (TRAP) staining, immunohistochemistry of the ED1 protein as a marker of the phagocyte system, and in situ hybridization with digoxigenin-labeled alpha1 chain of type I procollagen (COL1A1), osteopontin and osteocalcin. beta-TCP was resorbed in a chronological manner. Although new bone was not observed on day 4, fibroblast-like cells around beta-TCP were positive for COL1A1 and osteopontin mRNA. New bone formation presented after day 7. In the double-staining for OPN and ED1 on day 7, most cells around beta-TCP were positive for either osteopontin mRNA or ED1 protein. However, there were some doubly positive multinucleated cells, suggesting that they belonged to the mononuclear phagocyte system. After day 28, the implanted region was replaced with bone marrow. Multinucleated TRAP-positive and ED1-positive cells which adhered to beta-TCP at all stages seemed to be osteoclasts and they continuously resorbed beta-TCP. beta-TCP has a good biocompatibility since both bioresorption and bone formation started at an early stage after implantation.

IP-10 and Mig facilitate accumulation of T cells in the virus-infected liver.

Viral infection of the liver causes accumulation of T cells in the infected organ, raising the question as to the signals that mediate this response. Employing an adenovirus induced hepatitis model in mice, we show that IP-10 and Mig are essential for T cell recruitment and that induction of the two chemokines occurs concomitant to production of IFNgamma. It is shown that while IFNgamma induces IP-10 and Mig in hepatocytes, for optimal chemokine induction, a co-stimulatory signal mediated by cross-linking of Fas on hepatocytes is required. Moreover, cross-linking of Fas by injection of anti-Fas antibody into mice triggers induction of IP-10 and Mig in the liver. The cells providing the two signals are shown to express NK1.1 and AsGM1; elimination of these cells leads to inhibition of IFNgamma and chemokine transcript induction. The conclusion is drawn that both NK cells and T cells provide the two signals for induction of IP-10 and Mig in the liver.

Fenofibrate inhibits reactive amyloidosis in mice.

OBJECTIVE: To examine the effects of the lipid-lowering agent fenofibrate on experimental AA amyloidosis and on serum amyloid A (SAA) levels. METHODS: Fenofibrate was administered orally in a mouse model of amyloidosis, which is induced by injections of amyloid-enhancing factor and Freund's complete adjuvant. Fenofibrate was given for 3 weeks, including a 1-week course before induction of amyloidosis. Splenic amyloid deposits were evaluated histologically, and SAA levels were measured. RESULTS: Fenofibrate inhibited the formation of splenic amyloid deposits and suppressed the elevation of SAA levels. CONCLUSION; Fenofibrate inhibits experimental amyloidosis by reducing levels of the precursor SAA.