Search

Inadequate stem version might lead to impingement and instability after cementless total hip arthroplasty (THA). We evaluated (1) the distribution of short-stem anteversion, (2) the proportion of stems with an anteversion less than 5° or larger than 25°, (3) combined cup and stem anteversion, and (4) dislocation rate. We evaluated the native femoral anteversion and stem anteversion in 340 patients (340 THAs): 144 men and 196 women. Their mean age was 56.2 (22–87) years and mean body mass index was 25.1 (15.2–40.7) kg/m2. The femoral neck anteversion was measured on pre-operative CT scan and the stem anteversion was obtained during the operation. The safe zone of the stem anteversion was defined as 5 to 25°. The femoral neck anteversion ranged from −15 to 61° (mean, 15.0°; SD, ±10.6°). The stem anteversion ranged −7 to 50° (mean, 15.7°; SD, ±9.5°). It was optimal (5–25°) in 71.2% (242/340), insufficient ( 25°) in 15.6% (53/340). The stem anteversion had a medium correlation with the femoral neck anteversion (correlation coefficient = 0.449). The combined anteversion was 42.0° (range, 35.2–52.3°; SD, ±2.8°). During two to four year follow-up, no hip dislocated. Short-length stem had a great variability in the anteversion and considerable portion (28.9%, 98/340) of stems had an anteversion outside the safe zone. Surgeons should be aware of this variability of stem anteversion to compensate for abnormal stem anteversion, which might lead to impingement and instability after THA.

Sarcopenia, loss of muscle mass and strength, leads to functional dependence and disability. To date, no study reported the postoperative change of sarcopenia prevalence after hip fractures. Thus, we assessed postoperative changes in the prevalence of osteoporosis and sarcopenia in hip fracture patients.Among 1159 patients, who underwent surgery for low-energy hip fractures between May 2012 and December 2019, 224 patients (38 men and 186 women with a mean age of 76.8 ± 8.7 years) were studied with preoperative and follow-up dual-energy X-ray absorptiometry (DXA). Bone mineral density (BMD) and skeletal muscle mass were measured on DXA scans. The postoperative changes in the prevalence of osteoporosis and that of the sarcopenia were evaluated as well as Koval grade of the hip fracture patients.While there was no significant change in BMD, SMI significantly decreased postoperatively. Mean decrease of the SMI was 0.53 kg/mAfter hip fracture, osteoporosis seemed to be well managed and the prevalence of osteoporosis did not increase. However, SMI decreased and the prevalence of sarcopenia increased. More active measures are warranted to prevent sarcopenia in elderly hip fracture patients.

The results of total hip arthroplasty (THA) with use of Delta ceramic articulation were successful at medium term follow-up. The use of this newest ceramic has markedly reduced the incidence of ceramic head fractures, but not the incidence of ceramic liner fractures. We tested a hypothesis that the ceramic fractures are prevented by use of a metal shell with 18° inner taper angle and a stem design with a reduced neck geometry. We conducted a prospective multicenter study of cementless THA with use of 32/36-mm Delta ceramic bearing, Exceed ABT metal shell and Taperloc stem. We evaluated ceramic fracture, noise, clinical results, radiological changes and survival rate at a minimum of 5-year follow-up. From April 2010 to February 2012, 246 patients (274 THAs) were enrolled. Among them, 224 patients (130 men and 94 women, 250 hips) were followed-up for 5–8 years (mean 6.0 years). Ceramic malseating or fracture did not occur in any patient. Eight patients (8 hips, 3.2%) reported noise. Mean Harris hip score was 84 points at the latest follow-up. All acetabular and femoral components had bone-ingrown stability. Two hips were revised due to recurrent dislocation and periprosthetic fracture. The survival rate was 99.6% at 8 years postoperatively. Ceramic fractures can be prevented by a use of (1) 32/36-mm Delta ceramic bearing, (2) metal shell with 18° taper angle, and (2) stem with a reduced neck geometry. However, noise remains a concern of the Delta ceramic bearing. Therapeutic level II.

BACKGROUND: This randomized control study was designed to compare the clinical and radiological outcomes, including periprosthetic bone mineral density (BMD) changes, between the short and standard stems after using cementless hemiarthroplasty in elderly patients with femur neck fractures. MATERIALS AND METHODS: From January 2013 to May 2017, 151 patients (aged ≥ 65 years) underwent hemiarthroplasties due to femoral neck fractures. Patients were randomized into two groups; 77 patients in Group A implanting the short femoral stem and 74 patients in Group B implanting the standard femoral stem. Clinical and radiographic evaluations were performed in all patients. RESULTS: 75 patients (40 patients in Group A and 35 patients in Group B) completed routine follow-up for a minimum of 2 years. The clinical outcomes, including ambulatory functions and thigh pain, were similar in both groups. All the femoral stems acquired radiologic stability. At postoperative one year, BMD values in Gruen zone (G) seven on the standard stem side were significantly lower than those on the short stem side (P = 0.038). At the second year of follow-up, the BMD values of Group A in G1, G3, G4, and G7 were significantly greater than those of Group B (P = 0.007, 0.032, 0.026, and P

Bone mineral density (BMD) is significantly decreased after gastrectomy in patients with gastric cancer. Calcium malabsorption, secondary hyperparathyroidism, and dominant bone resorption appear to contribute to bone loss in these patients. Patients should undergo early surveillance and nutritional or pharmacologic intensive interventions for bone health. Survivorship care, including bone health, has become an important issue in gastric cancer. We performed a meta-analysis of the available observational studies to determine whether and how osteoporosis risk is increased after gastrectomy in patients with gastric cancer. A total of 1204 patients (802 men) from 19 cohort studies were included. We evaluated the prevalence of osteoporosis in postgastrectomy patients, comparing the incidence according to the type of gastrectomy and sex. Additionally, we evaluated changes in bone mineral density (BMD) and bone metabolism-related markers pre- to postoperatively and between patients who underwent gastrectomy and matched controls. Proportion meta-analysis was performed and pooled odds ratios (ORs) were calculated. The pooled incidence estimate was 36% [95% confidence interval (CI), 32–40]. The incidence of osteoporosis was significantly higher in women than in men (OR = 1.90, p < 0.001) but was similar between partial and total gastrectomy groups (OR = 0.983, p = 0.939). BMD was significantly decreased, and calcium, phosphorous, and parathyroid hormone levels were significantly increased in patients after gastrectomy compared to those before gastrectomy. BMD and calcium and 25OH-vitamin D levels were significantly decreased, and parathyroid hormone and 1,25OH-vitamin D levels were significantly increased in the gastrectomy group compared to that in the control group. We found that BMD is significantly decreased after gastrectomy in patients with gastric cancer. Vitamin D deficiency and secondary hyperparathyroidism are suggested to be common mechanism underlying BMD impairment. After resection, patients should undergo long-term nutritional and bone health surveillance, in addition to their oncological follow-up.

Background The annual number of hip arthroplasties is increasing combined with the aging population worldwide. In accordance with the increasing number of primary hip arthroplasties, the number of revision total hip arthroplasties (THAs) is expected to increase. The incidence and burden of revision THAs in the United States and have been reported by registry studies. To identify potential differences according to ethnics and regional practice, it is important to obtain data from East Asia. Nevertheless, there has been a lack of studies on the burden and future projection of revision THA based on a large-scale database in East Asia. The purpose of this study was to evaluate annual incidence and burden of revision THAs and to project the future burden in South Korea. Methods We identified primary THAs, primary hemiarthroplasties (HAs) and revision THAs, which were performed from 2010 to 2018, using database of Health Insurance and Review and Assessment (HIRA); nation-wide medical claim system of South Korea. The annual incidence rates (per 100,000) of primary THA, primary HA and revision THA, and the annual burden of revision THA; the number of revision THAs divided by the sum of primary hip arthroplasties and revision THAs, were calculated. The future burden of revision THAs were projected through 2030 using generalized linear model with Quasi-poisson regression. Results During the 9-year period, the annual incidences of primary THA, primary HA and revision THA increased by 47, 29 and 3%, respectively, while the revision burden decreased from 0.13 to 0.10. Compared to 2018, the annual incidences of primary THA, HA, and revision THA were projected to increase by 7.2, 2.3 and 1.1% per year, respectively, whereas the burden of revision THA was projected to decrease to 0.07 in 2030. Conclusion Trends of revision THA in South Korea were similar with those of national registry studies from the United States. The annual incidence of revision THA has steadily increased, whereas its burden has decreased. Findings of our study could be used for epidemiological comparison between Western countries and East Asia as well as for the establishment of medical policies of revision THA in East Asian countries.

Patient-reported outcomes (PROs) provide practical guides for treatment; however, studies that have evaluated PROs of women in Korea with postmenopausal osteoporosis (PMO) are lacking. This cross-sectional, multi-center (29 nationwide hospitals) study, performed from March 2013 to July 2014, aimed to assess PROs related to treatment satisfaction, medication adherence, and quality of life (QoL) in Korean PMO women using osteoporosis medication for prevention/treatment. Patient demographics, clinical characteristics, treatment patterns, PROs, and experience using medication were collected. The 14-item Treatment Satisfaction Questionnaire for Medication (TSQM) (score-range, 0-100; domains: effectiveness, side effects, convenience, global satisfaction), Osteoporosis-Specific Morisky Medication Adherence Scale (OS-MMAS) (score-range, 0-8), and EuroQol-5 dimensions questionnaire (index score range, - 0.22 to 1.0; EuroQol visual analog scale score range, 0-100) were used. To investigate factors associated with PROs, linear (treatment satisfaction/QoL) or logistic (medication adherence) regression analyses were conducted. A total of 1804 patients (age, 62 years) were investigated; 60.1% used bisphosphonate, with the majority (67.2%) using weekly medication, 27.8% used daily hormone replacement therapy, and 12.1% used daily selective estrogen receptor modulator. Several patients reported gastrointestinal (GI) events (31.6%) and dental visits due to problems (24.1%) while using medication. Factors associated with the highest OS-MMAS domain scores were convenience and global satisfaction. GI events were associated with non-adherence. TSQM scores for effectiveness, side effects, and GI risk factors were significantly associated with QoL. Our study elaborately assessed the factors associated with PROs of Korean PMO women. Based on our findings, appropriate treatment-related adjustments such as frequency/choice of medications and GI risk management may improve PROs.

BackgroundPostoperative delirium (POD) is a common clinical syndrome with significant negative outcomes. Thus, we aimed to evaluate the feasibility and effectiveness of a delirium screening tool and multidisciplinary delirium prevention project.MethodsA retrospective cohort study was conducted at a single teaching center in Korea. A cohort of patients who underwent a delirium prevention program using a simple delirium screening tool from December 2018 to February 2019 (intervention group,N = 275) was compared with the cohort from the year before implementation of the delirium prevention program (December 2017 to February 2018) (control group,N = 274). Patients aged ≥65 years who were admitted to orthopedic wards and underwent surgery were included. The incidence rates of delirium before and after implementation of the delirium prevention program, effectiveness of the delirium screening tool, change in the knowledge score of nurses, and length of hospital stay were assessed.ResultsThe sensitivity and specificity of the screening tool for the incidence of POD were 94.1 and 72.7%, respectively. The incidence rates of POD were 10.2% (control group) and 6.2% (intervention group). The odds ratio for the risk reduction effect of the project related to the incidence of POD was 0.316 (95% confidence interval: 0.125–0.800,p = 0.015) after adjustment for possible confounders. The delirium knowledge test score increased from 40.52 to 43.24 out of 49 total points (p p = 0.062).ConclusionThe screening tool successfully identified patients at a high risk of POD at admission. The POD prevention project was feasible to implement, effective in preventing delirium, and improved knowledge regarding delirium among the medical staff.Trial registrationNone.

Core decompression (CD) has been used to treat early-stage (pre-collapse) osteonecrosis of the femoral head (ONFH) in an attempt to prevent collapse. Recently, other adjunctive treatments including bone grafting (BG) and bone marrow mononuclear cells (BMMC) were combined to traditional CD to improve the results. We assessed the efficacy of various CD modalities and non-operative treatment through a network meta-analysis (NMA). Nine randomized controlled trials with a minimum two year follow-up were retrieved from PubMed, Embase, and Cochrane Library search. Treatment modalities categorized into five; (1) traditional CD alone, (2) CD combining BG, (3) CD combining BMMC, (4) CD combining BG and BMMC, and (5) non-operative treatment. The rate of conversion to total hip arthroplasty (THA) and the radiologic progression were compared among the five treatments. A total of 453 hips were included in our NMA; 151 hips in CD, 70 hips in CD combining BG, 116 hips in CD combining BMMC, 25 hips in CD combining BG and BMMC, and 91 hips in non-operative treatment. There were no differences in the rate of THA conversion across all five treatment modalities. The pooled risk ratio compared with non-operative treatment for THA conversion was 0.92 (95% CI, 0.19–4.43; p = 0.915) in traditional CD; 4.10 (95% CI, 0.37–45.42; p = 0.250) in CD combining BG; 0.30 (95% CI, 0.04–2.49; p = 0.267) in CD combining BMMC; and 1.78 (95% CI, 0.05–63.34; p = 0.750) in CD combining BG and BMMC. No significant differences were found in terms of the radiologic progression across all treatments. In the current NMA, we did not find any differences in the rates of THA conversion and radiologic progression across all CD modalities and non-operative treatment. These results question the assumption that CD changes the natural course of ONFH. Considering that size of necrotic portion is the major determinant of future collapse of the necrotic femoral head and the collapse does not occur in small lesions even without any treatment, a large-scale randomized controlled trial is necessary to confirm the effectiveness of CD. Level I, meta-analysis.

Osteonecrosis of the femoral head (ONFH) is commonly detected in young patients and most surgeons tend to delay total hip arthroplasty (THA) until the end stage of the disease. We hypothesised that post-operative range of motion (ROM) of the hip as well as baseline ROM at the time of surgery decreases with the disease progression. The purpose of this study was to determine whether patients, who were operated at an advanced stage, have pre- and post-operative hip ROM similar to ROM of patients, who were operated at earlier stages. Eight hundred and fifty patients (850 hips) treated with THA for ONFH were classified according to pre-operative stages of Association Research Circulation Osseous (ARCO). Fifty-six patients were operated at stage 2, 458 at stage 3, and 336 at stage 4. Pre-operative and one year post-operative ROM was compared among the stages. Pre-operative sum of hip ROM decreased with the progression of ARCO stage (P

This study examined differences between men and women in factors affecting anti-osteoporosis drug treatment after osteoporotic fracture. Using a national claims database, we analyzed patients aged 50 years and older who experienced their first osteoporotic fracture between January 1, 2008, and December 31, 2012. We examined whether patients were prescribed anti-osteoporosis drugs within 6 months post-fracture. Factors associated with treatment status were identified using multivariate logistic regression. Among a total of 556,410 patients aged 50 and older, only 37% were prescribed anti-osteoporosis drugs within 6 months post-fracture. Female patients with fractures were more likely to receive pharmacotherapy than male patients (41.7 vs. 19.3%). Older age significantly increased the likelihood of receiving anti-osteoporosis drugs after osteoporotic fracture. For men, the adjusted odds ratio for receiving therapy was greatest in those aged 80 years and older (OR 6.4), and for women, it was largest in those aged 70-79 (OR 3.33). Both men and women were more likely to be prescribed drugs after a spine fracture, with men having significantly greater odds of receiving drug therapy (men, OR 7.1, 95% CI 6.5-7.9; women 4.79, CI 4.63-4.96). Patients with rheumatic disease or other osteoporosis-inducing comorbid disease were more likely to be prescribed anti-osteoporosis drugs. Our findings indicate that a lack of anti-osteoporosis pharmacotherapy after fracture remains a problem in Korea, especially among men, highlighting the need for effective quality improvement interventions to maximize post-fracture treatment rates.

The purpose of this study was to investigate the reasons for delayed surgery in patients with proximal hip fracture and to compare differences in mortality between delayed surgery cases and non-delayed surgery cases. In addition, we evaluated causal factors for delayed surgery that affected differences in mortality. From 2003 to 2013, 1290 patients (1290 hips) with unilateral femoral neck or intertrochanteric fractures who underwent surgery were categorized into Group Ia (402 patients, early surgery group) and Group Ib (888 patients, delayed surgery group). The delayed surgery group was categorized as Group IIa (270 patients, pre-hospital delay group) and Group IIb (618 patients, post-hospital delay group). Among 618 patients with post-hospital delay, 165 patients in Group IIIa were defined as delayed surgery cases due to patient factors, and 453 patients in Group IIIB were defined as delayed surgery cases due to hospital factors. Early and late mortality was compared between each group. Of 1290 patients, 888 patients underwent delayed surgery (mean 7.5 days, range 3–167 days) after hip fracture. The cumulative mortality rate at 30, 60 days, 3, and 12 months was 0.7, 2.0, 3.0, and 9.5% in Group Ia, respectively, and 2.4, 4.5, 5.2, and 14.5% in Group Ib, respectively (p = 0.047, p = 0.027, p = 0.078, and p = 0.012, respectively). Of 618 patients with post-hospital surgery delay, the cumulative mortality rate at 30 days and 12 months was 4.8 and 21.2% in Group IIIa, respectively, and 1.8, and 12.6% in Group IIIb, respectively (p = 0.033 and p = 0.008, respectively). After adjustments, patient factors for delayed surgery (HR 2.780; 95% CI 1.012–7.640, p = 0.047) were significantly associated with death after hip fracture. This study demonstrated that delayed surgery was significantly related to 30-day and 1-year mortality. Surgery delay due to drugs’ hold and medical comorbidity was related to 30-day mortality after adjustment.

We translated and adapted transculturally the Quality of Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO-41) for Korean patients. The translated Korean version of QUALEFFO-41 showed satisfactory reliability and validity. The aim of this study was to translate the QUALEFFO-41 for Korean patients and then validate the Korean version of QUALEFFO-41. Translation and transcultural adaptation of the QUALEFFO-41 was conducted according to the international recommendations. Ninety-seven patients (mean age, 73.6 years) with osteoporosis were participated in validating the Korean version of QUALEFFO-41. To test reliability, internal consistency was evaluated using Cronbach’s alpha coefficient. To test validity, convergent validity was assessed using correlation with the SF-12 and EQ-5D and discriminant validity was assessed using ROC curve analysis. The English version of QUALEFFO-41 was translated and adapted to Korean without notable discrepancies. The Korean QUALEFFO-41 had good reliability with Cronbach’s alpha ranging from 0.733 to 0.942. QUALEFFO-41 had good correlations to SF-12 and EQ-5D. Compared with subjects without history of vertebral fracture (VF), those with history of VF showed significantly worse scores according to QUALEFFO-41, but not according to SF-12 or EQ-5D. ROC curve analysis revealed that the physical function domain of QUALEFFO-41 had significant ability to discriminate between subjects with and without history of VF, while SF-12 or EQ-5D did not. The Korean version of QUALEFFO-41 demonstrated relevant internal consistency, convergent validity, and discriminant validity, which can be recommended to evaluate quality of life in Koreans.

Background Early detection followed by prompt intervention is essential for the treatment of periprosthetic joint infection (PJI). D-dimer, a fibrin degradation product, characteristically changes rapidly during early postoperative period and has a short half-life. The aim of this prospective study was to measure postoperative change of D-dimer level after joint arthroplasty in conjunction with ESR and CRP. Methods ESR, CRP, and D-dimer levels were measured on the day before surgery, postoperative days 1, 2, 3, and 5 and weeks 2 and 6 in 65 patients who underwent elective primary total hip arthroplasty (38 hips in 38 patients) or total knee arthroplasty (27 knees in 27 patients). We compared perioperative changes of the three biomarkers. Results ESR level was elevated from postoperative day 1 and reached a peak level of 45 mm/h at postoperative day 5. The elevation persisted until postoperative week 6. CRP level was elevated from postoperative day 1 and reached a peak level of 10 mg/dl between postoperative day 2 and day 3. The CRP level was decreased to the normal level around postoperative week 2. D-dimer level was sharply elevated and peaked to 4.5 μg/dl at postoperative day 1. At postoperative day 2, it decreased to baseline level. After then, it slowly elevated again and reached a second peak at postoperative week 2. Conclusion D-dimer showed a more rapid rise and fall than ESR and CRP in very early postoperative period. The D-dimer test might be effective in early detection of PJI, if combined with levels of ESR and CRP. The postoperative change of D-dimer in our study can serve as a baseline for early diagnosis of PJI.

We determined the incidence of second hip fracture and evaluated whether compliant users of bisphosphonate had a lower incidence of second hip fracture after prior hip fracture. Bisphosphonate has been used to prevent osteoporotic fracture and is recommended for the secondary prevention after hip fracture. However, little is known regarding secondary prevention after first hip fracture. Our purpose was to determine the incidence of second hip fracture and to evaluate whether compliant use of bisphosphonate can reduce the risk of second hip fracture. Eight hundred twenty-six patients who sustained the first hip fracture from May 2003 to October 2011 were retrospectively evaluated. The incidence of second hip fracture was compared between compliant users of bisphosphonate and nonusers. Seventy-one (8.6 %) patients suffered a second hip fracture at mean 30.0 months (SD 24.6, range 1 to 90 months) after the initial hip fracture. The cumulative incidence of second hip fracture was 5.1 % (42/826) at 2 years and 8.6 % (71/826) at 8 years. The incidence of second hip fracture was 4.2 % (12/283) in compliant users and 10.9 % (59/543) in nonusers (p = 0.001). Compliant use of bisphosphonate is effective in the prevention of second hip fractures.

We medicated teriparatide in three patients, who had a nonunion of the femur even after the initial surgical intervention. Teriparatide was administered for 3-9 months after a diagnosis of nonunion. A successful union was obtained in all three patients without further surgical intervention, and no adverse events related to the use of teriparatide were observed. Our report showed that teriparatide could be an alternative to surgical intervention in nonunion of the femur.

The purpose of this study was first, to determine the sensitivity, specificity, and accuracy of MDCT arthrography (CTA) for the diagnosis of acetabular labral tear and sulcus; second, to correlate tear types using the Lage classification system on CTA compared with the arthroscopic classification; and third, to correlate CTA localization with arthroscopic localization. Direct CTA was performed using 16- or 64-slice MDCT in 126 hips (124 patients) who had chronic groin pain and positive impingement test. Images were reviewed and evaluated by two experienced musculoskeletal radiologists preoperatively. CTA findings were compared with arthroscopic findings in 58 hips (56 patients) under consensus by two orthopedic surgeons. Forty-one of the 58 hips were diagnosed as labral tears on CT arthrography. Forty-three of the 58 hips were shown to have a labral tear on arthroscopy. Sensitivity, specificity, and accuracy for detecting labral tear and sulcus by CTA were 90.7%, 86.7%, and 89.7%, and 93.8%, 97.6% and 96.6% respectively for observer 1, and 90.7% and 80.0%, 87.9% and 87.5%, 95.2%, and 93.1 % respectively for observer 2. Thirty-five out of 41 hips (85%) that were diagnosed with labral tear on CTA correlated substantially with arthroscopic Lage classification (kappa coefficient = 0.65). CTA and arthroscopic findings showed similar distribution patterns of the tears with most lesions located in antero- and postero-superior areas (p = 0.013). Direct CT arthrography using MDCT may be a useful diagnostic technique in the detection of acetabular labral tear.

Septic hip is rare in patients with femoral head osteonecrosis (FHON) and has been known to occur in those who are immune compromised. Thus, surgeons do not concern about the superimposed septic hip in immunocompetent patients. We report five patients who had FHON and concomitant septic arthritis of the hip. No patients were immune compromised. All patients had an elevation of ESR and CRP. Two patients had an otherwise unexplained fever preoperatively. Two patients had had a remote septic focus. When a patient with FHON has an unexplained elevation of ESR and CRP, concomitant septic arthritis of the hip should be suspected even though the patient is not immune compromised.

Although the Korean population does not have high risk for osteoporosis, the numbers of osteoporosis-related fractures represent a considerable economic burden to society. The purpose of this study was to determine the incidence and residual lifetime risk of osteoporosis-related fractures in Korea, using data from the Health Insurance Review and Assessment Service (HIRA), which includes nationwide information compiled by the Korean government. All new visits or admissions to Korean clinics or hospitals for fractures were recorded prospectively in a nationwide cohort by the Korean HIRA using the International Classification of Diseases, 10th revision, codes and procedure codes. These data were retrospectively evaluated to determine the incidence and residual lifetime risk of osteoporosis-related fractures (hip, spine, distal radius, and humerus fractures), in men and women aged 50 years or more between 2005 and 2008. The annual incidences of osteoporosis-related fractures were 1,661, 1,646, 1,623, and 1,614 per 100,000 person-years in men and women aged 50 years or more from the year 2005 to 2008. The annual incidence of osteoporosis-related fracture in women was three times that of men. The incidence of osteoporosis-related fractures increased with advancing age. In Korea, at the age of 50 years, the residual lifetime probabilities of osteoporosis-related fractures are 59.5% for women and 23.8% for men. This study presents the baseline data for treatment and research on osteoporosis and provides an estimate of osteoporosis-related fractures in Korea.

Lipid rafts are membrane platforms for signaling molecules that regulate various cellular functions. During osteoclastogenesis, lipid rafts also have been shown to play a crucial role for cell fusion upon RANK/RANKL interaction and further activation of osteoclasts, resulting in bone resorption. To investigate proteins that localize in lipid rafts, we conducted two-dimensional (2D) gel electrophoresis followed by MALDI-TOF mass spectrometry. We identified 12 functional proteins among 34 proteins that were detectable by silver staining of the 2D gel. Among them, a subunit of vacuolar H(+)-ATPase that is involved in resorption activity of osteoclasts was identified showing an approximate molecular weight of 56.94 kDa and pI of 5.4. The solubilization of osteoclast membrane proteins followed by sucrose density gradient fractionation confirmed that V-ATPase colocalized with flotillin-1, a marker of lipid rafts, in low-density detergent-insoluble fractions. Disruption of rafts with cholesterol-sequestering agents or introduction of a dominant-negative mutant of TRAF6 impaired V-ATPase activity. These data indicate that integrity of lipid rafts regulates the activity of V-ATPase in osteoclasts, suggesting that cholesterol-lowering agents might be useful for inhibiting osteoclast-dependent bone resorption.

Dear Editor, We read with great interest the article by Korthoewer and Chandran [1], in which the authors presented physicians’ attitudes regarding osteoporosis management in general and more specifically with respect to utilization of theWHOFracture Risk Assessment Tool (FRAX®) in the Asia-Pacific region. In Table 2, they showed the proportion of physicians in each country who had an awareness of FRAX, as well as the percentage who used the tool in practice. Some readers must be curious as to the reason for the low usage despite the fact that all of the respondents from Korea and Brunei were aware of the FRAX tool. We suggest that there are other considerations. The number of participants from Brunei and Korea was only two and one, respectively, which is too small to permit generalization of the results to the broader population. As such, the reasons for the lack of utilization of the tool in practice should be reevaluated before widespread adoption throughout Asia-Pacific. Ha et al. recently surveyed members of the Korean Society for Bone and Mineral Research (KSBMR) regarding contemporary issues, including use of the FRAX tool [2]. Their survey showed that most respondents in Korea (88 %) were aware of the tool, and that approximately 20 % of these participants also used the tool in their practice. The most common reasons for lack of use were “too busy and hence lack of time to perform a FRAX calculation” 76%, followed by the “feeling that the FRAX tool was not applicable to their practice” 13 %. A second factor to consider is the reimbursement system established by the Korean government. Reimbursement guidelines for osteoporosis treatment not yet include fracture risk assessment techniques such as FRAX, and currently require assessment of bone mineral density (BMD) using dual X-ray absorptiometry (DXA). According to the recent International Osteoporosis Foundation (IOF) audit, Korea has the highest number of DXA machines among all Asian countries 24.5 machines per one million population (http://www. iofbonehealth.org/sites/default/files/media/PDFs/Regional% 20Audits/2013-Asia_Pacific_Audit-Rep_Korea_0_0.pdf) These are two possible reasons for the low FRAX utilization rates in Korea. Although we do not know the exact situation in Brunei, there may be other similar or unique considerations. We suggest, therefore, that the status of osteoporosis management should be evaluated individually within each country, given that situations and circumstances may vary across the Asia-Pacific region.

Introduction: Although IL-1 beta is believed to be crucial in the pathogenesis of osteoarthritis (OA), the IL-1 beta blockade brings no therapeutic benefit in human OA and results in OA aggravation in several animal models. We explored the role of a cytokine signaling 1 (SOCS1) suppressor as a regulatory modulator of IL-1 beta signaling in chondrocytes. Methods: Cartilage samples were obtained from patients with knee OA and those without OA who underwent surgery for femur-neck fracture. SOCS1 expression in cartilage was assessed with immunohistochemistry. IL-1 beta-induced SOCS1 expression in chondrocytes was analyzed with quantitative polymerase chain reaction and immunoblot. The effect of SOCS1 on IL-1 beta signaling pathways and the synthesis of matrix metalloproteinases (MMPs) and aggrecanase-1 was investigated in SOCS1-overexpressing or -knockdown chondrocytes. Results: SOCS1 expression was significantly increased in OA cartilage, especially in areas of severe damage (P < 0.01). IL-1 beta stimulated SOCS1 mRNA expression in a dose-dependent pattern (P < 0.01). The IL-1 beta-induced production of MMP-1, MMP-3, MMP-13, and ADAMTS-4 (aggrecanase-1, a disintegrin and metalloproteinase with thrombospondin motifs 4) was affected by SOCS1 overexpression or knockdown in both SW1353 cells and primary human articular chondrocytes (all P values < 0.05). The inhibitory effects of SOCS1 were mediated by blocking p38, c-Jun N-terminal kinase (JNK), and nuclear factor.B (NF-kappa B) activation, and by downregulating transforming growth factor-beta-activated kinase 1 (TAK1) expression. Conclusions: Our results show that SOCS1 is induced by IL1-beta in OA chondrocytes and suppresses the IL-1 beta-induced synthesis of matrix-degrading enzymes by inhibiting IL-1 beta signaling at multiple levels. It suggests that the IL-1 beta-inducible SOCS1 acts as a negative regulator of the IL-1 beta response in OA cartilage.

In the fourth paragraph of the Discussion section of this article, the second sentence states: “One study reported a protective effect of bisphosphonate for the prevention of a second hip fracture.” This is incorrect. The sentence should read as follows, substituting the word “adverse” for “protective”: “One study reported an adverse effect of bisphosphonate for the prevention of a second hip fracture.” The authors apologize for this error.