Validation of the Western Ontario and McMaster Universities Arthritis Index Short Form (WOMAC-SF) and Its Relevance to Disability and Frailty

PURPOSE: This study aimed to evaluate the validity of the Western Ontario and McMaster Universities Arthritis Index Short Form (WOMAC-SF) for the assessment of musculoskeletal disorders. We evaluated whether WOMAC-SF correlated with the World Health Organization Disability Assessment Schedule 12 (WHODAS-12) and Kaigo-Yobo questionnaires for assessing health-outcomes in Korea.MATERIALS AND METHODS: This cross-sectional study used data from the Namgaram-2 cohort. WOMAC, WOMAC-SF, WHODAS-12, and Kaigo-Yobo questionnaires were administered to patients with musculoskeletal disorders, including radiology-confirmed knee osteoarthritis (RKOA), sarcopenia, and osteoporosis. The relationships among WOMAC-SF, WHODAS-12, and Kaigo-Yobo scores were analyzed by stepwise multiple regression analysis.RESULTS: WOMAC-SF was associated with the WOMAC questionnaire. The results of confirmatory factor analysis for the hypothesized model with two latent factors, pain and function, provided satisfactory fit indices. WOMAC-SF pain and function were associated with RKOA. Kaigo-Yobo was associated with WOMAC-SF pain (B=0.140, p=0.001) and WOMAC-SF function (B=0.042, p=0.004). WHODAS-12 was associated with WOMAC-SF pain (B=0.679, p=0.003) and WOMAC-SF function (B=0.804, p<0.001).CONCLUSION: WOMAC-SF was validated for the evaluation of low extremity musculoskeletal disorders and health-related quality of life in a community-based population. Furthermore, we confirmed that WOMAC-SF were reflective of disability and frailty, which affect health outcomes.

A Review of the Literature on Culture-Negative Periprosthetic Joint Infection: Epidemiology, Diagnosis and Treatment

PURPOSE: The prevalence of periprosthetic joint infection (PJI) has increased with the increasing incidence of arthroplasty surgery. Considering identification of causative microorganisms is crucial for treatment of PJI, culture-negative (CN) PJI is a significant clinical issue. The purpose of the present study is to describe epidemiology, diagnosis and treatment of CN PJI based on review of the literature to help prevent delayed diagnosis and improve clinical outcomes of CN PJI. METHODS: MEDLINE, EMBASE, Cochrane Library and Scopus databases were searched for articles on CN PJI. Only clinical studies written in English were included. Basic science studies, letters to the editor, case reports and review articles on PJI were excluded. RESULTS: Seven studies were included in this study. The prevalence of CN PJI ranged from 0% to 42.1%. The major risk factors for CN PJI were prior antibiotic use and presence of postoperative wound drainage. Vancomycin and cephalosporins were the most commonly used antibiotics for CN PJI. Two-stage revision arthroplasty followed by 6 weeks of antibiotic therapy produced the most successful treatment outcomes. CONCLUSIONS: In most clinical studies on CN PJI, a definite diagnostic method for identifying causative microorganisms or optimal treatment strategy for CN PJI were not clearly described. Therefore, further studies are needed to establish standard diagnostic methods for identifying infecting organisms and treatment strategies for CN PJI.

Betulin suppressed interleukin-1β-induced gene expression, secretion and proteolytic activity of matrix metalloproteinase in cultured articular chondrocytes and production of matrix metalloproteinase in the knee joint of rat

We investigated whether betulin affects the gene expression, secretion and proteolytic activity of matrix metalloproteinase-3 (MMP-3) in primary cultured rabbit articular chondrocytes, as well as in vivo production of MMP-3 in the rat knee joint to evaluate the potential chondroprotective effect of betulin. Rabbit articular chondrocytes were cultured and reverse transcription-polymerase chain reaction (RT-PCR) was used to measure interleukin-1β (IL-1β)-induced gene expression of MMP-3, MMP-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4), ADAMTS-5 and type II collagen. Effect of betulin on IL-1β-induced secretion and proteolytic activity of MMP-3 was investigated using western blot analysis and casein zymography, respectively. Effect of betulin on MMP-3 protein production was also examined in vivo. The results were as follows: (1) betulin inhibited the gene expression of MMP-3, MMP-1, MMP-13, ADAMTS-4, and ADAMTS-5, but increased the gene expression of type II collagen; (2) betulin inhibited the secretion and proteolytic activity of MMP-3; (3) betulin suppressed the production of MMP-3 protein in vivo. These results suggest that betulin can regulate the gene expression, secretion, and proteolytic activity of MMP-3, by directly acting on articular chondrocytes.

Erratum to: Betulin suppressed interleukin-1b-induced gene expression, secretion and proteolytic activity of matrix metalloproteinase in cultured articular chondrocytes and production of matrix metalloproteinase in the knee joint of rat

Due to an oversight of the editorial team, the original version of this article contained an error in the list of authors.

Risk Factors of Cage Subsidence after Posterior Lumbar Interbody Fusion

STUDY DESIGN: Retrospective study. OBJECTIVES: The purpose of this study was to evaluate risk factors for subsidence after posterior lumbar interbody fusion (PLIF). SUMMARY OF LITERATURE REVIEW: Body mass index (BMI), bone mineral density (BMD), cage characteristics (titanium or poly-ether-ether-ketone (PEEK)) and degree of disc distraction are risk factors for cage subsidence after PLIF. MATERIALS AND METHODS: From January 2010 to January 2015, a total of 69 patients (93 segments) who were diagnosed with degenerative lumbar spine disease at the current authors' institution and underwent follow-up for at least 1 year were included in this retrospective study. Data on all factors related to cage subsidence were taken into consideration. The degree of association for each of the factors was determined through the calculation of odds ratios (ORs) with a 95% confidence interval. Logistic regression analyses were performed. The P-value that represented statistical significance was set below 0.05. RESULTS: There were no significant associations between fused segment level and cage subsidence (p=0.588), nor were there any significant associations between the kind of cage (titanium or PEEK) and cage subsidence (p=0.371). Using logistic regression, the factors with a P-value below the 0.20 level in univariate analyses were included in the multivariate analyses. In multivariate analyses, diabetes mellitus (DM) (p=0.029, OR, 4.524), osteoporosis (p=0.026, OR, 6.046), and degree of disc distraction (p=0.010, OR, 1.446) had significant associations with cage subsidence. In addition, there were significant associations between cage subsidence and instrument failure (p=0.008, OR, 8.235). CONCLUSIONS: DM and osteoporosis, which may affect bony structures, have significant associations with cage subsidence after PLIF. Cage insertion with excessive disc distraction during surgery may also affect cage subsidence after PLIF.

Risk Factors of Cervical Spondylosis in Workers Requiring Neck Flexion and Extension Actions in Farming and Fishing Communities / 대한정형외과학회잡지

PURPOSE: The purpose of this study is to determine the relationship between the repetitive flexion or extension posture on the cervical spine on labor and degenerative change of the cervical spine, and the factors affecting degenerative change of the cervical spine. MATERIALS AND METHODS: To determine the factors affecting degenerative change of the cervical spine, age, sex, height, weight, body mass index, smoking, diabetes mellitus (DM), time engaging in labor, and cervical spine posture (flexion or extension) required repetitively on labor were investigated in the subjects. In addition, to evaluate the level of degenerative change of the cervical spine on 83 people in the flexion group (flexion strain) and 83 people in the extension group (extension strain), cervical degenerative index (CDI) in the simple cervical spine lateral radiograph was used to score (0-60 points) the degenerative severity. RESULTS: A total of 166 subjects (flexion group: 83 people, extension group: 83 people) participated in this study, and for the CDI, the cervical spine flexion group scored 7.8±6.2 points, and the cervical spine extension group scored 12.2±6.0 points to show that the cervical spine extension group had significant degenerative change in the cervical spine. In the multiple linear regression test performed to verify the risk factors affecting the degenerative change of the cervical spine, age (p=0.004), contraction of DM (p=0.029), and extension posture of cervical spine (p<0.001) influenced the degenerative change of the cervical spine. CONCLUSION: Repetitive extension posture on the cervical spine on labor and contraction of diabetes affected degenerative change of the cervical spine, therefore, training in medical care and posture on labor are required to prevent the progression of degenerative change in the cervical spine.

Nonalcoholic Fatty Liver Disease Is Associated with the Presence and Morphology of Subclinical Coronary Atherosclerosis

PURPOSE: In this study, we aimed to evaluate whether nonalcoholic fatty liver disease (NAFLD) was associated with the presence and morphology of coronary atherosclerotic plaques shown by multidetector computed tomography (MDCT) in asymptomatic subjects without a history of cardiovascular disease. MATERIALS AND METHODS: We retrospectively enrolled 772 consecutive South Korean individuals who had undergone both dualsource 64-slice MDCT coronary angiography and hepatic ultrasonography during general routine health evaluations. The MDCT studies were assessed for the presence, morphology (calcified, mixed, and non-calcified), and severity of coronary plaques. RESULTS: Coronary atherosclerotic plaques were detected in 316 subjects (40.9%) by MDCT, and NAFLD was found in 346 subjects (44.8%) by hepatic ultrasonography. Subjects with NAFLD had higher prevalences of all types of atherosclerotic plaque and non-calcified, mixed, and calcified plaques than the subjects without NAFLD. However, the prevalence of significant stenosis did not differ between groups. After adjusting for age, smoking status, diabetes mellitus, hypertension, dyslipidemia, and metabolic syndrome, NAFLD remained a significant predictor for all types of coronary atherosclerotic plaque [odds ratio (OR): 1.48; 95% confidence interval (CI): 1.05-2.08; p=0.025] in binary logistic analysis, as well as for calcified plaques (OR: 1.70; 95% CI: 1.07-2.70; p=0.025) in multinomial regression analysis. CONCLUSION: Our study demonstrated that NAFLD was significantly associated with the presence and the calcified morphology of coronary atherosclerotic plaques detected by MDCT. Further prospective clinical studies are needed to clarify the exact physiopathologic role of NAFLD in coronary atherosclerosis.