Ossification of the posterior longitudinal ligament (OPLL) can be defined as an ectopic ossification in the tissues of spinal ligament showing a hyperostotic condition. OPLL is developed mostly in the cervical spine and clinical presentations of OPLL are majorly myelopathy and/or radiculopathy, with serious neurological pathology resulting in paralysis of extremities and disturbances of motility lowering the quality of life. OPLL is known to be an idiopathic and multifactorial disease, which genetic factors and non-genetic factors including diet, obesity, physical strain on the posterior longitudinal ligament, age, and diabetes mellitus, are involved into the pathogenesis. Up to now, surgical management by decompressing the spinal cord is regarded as standard treatment for OPLL, although there might be the risk of development of reprogression of ossification. The molecular pathogenesis and efficient therapeutic strategy, especially pharmacotherapy and/or preventive intervention, of OPLL has not been clearly elucidated and suggested. Therefore, in this review, we tried to give an overview to the present research results on OPLL, in order to shed light on the potential pharmacotherapy based on molecular pathophysiologic aspect of OPLL, especially on the genetic/genomic factors involved into the etiology of OPLL.

We evaluated the chondroprotective effects of wogonin by investigating its effects on the gene expression and production of matrix metalloproteinase-3 (MMP-3) in primary cultured rabbit articular chondrocytes, as well as on production of MMP-3 in the rat knee. Rabbit articular chondrocytes were cultured in a monolayer, and RT-PCR was used to measure interleukin-1β (IL-1β)-induced expression of MMP-3, MMP-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4), and type II collagen. In rabbit articular chondrocytes, the effects of wogonin on IL-1β-induced production and proteolytic activity of MMP-3 were investigated using western blot analysis and casein zymography, respectively. The effect of wogonin on MMP-3 protein production was also examined in vivo. In rabbit articular chondrocytes, wogonin inhibited the expression of MMP-3, MMP-1, MMP-13, and ADAMTS-4, but increased expression of type II collagen. Furthermore, wogonin inhibited the production and proteolytic activity of MMP-3 in vitro, and inhibited production of MMP-3 protein in vivo. These results suggest that wogonin can regulate the gene expression and production of MMP-3, by directly acting on articular chondrocytes.

We investigated whether prunetin affects the proteolytic activity, secretion, and gene expression 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 eff ect of prunetin. Rabbit articular chondrocytes were cultured in a monolayer, and reverse transcription-polymerase chain reaction (RT-PCR) was used to measure interleukin-1β (IL-1β)-induced expression of MMP-3, MMP-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4), and ADAMTS-5. In rabbit articular chondrocytes, the effects of prunetin on IL-1β-induced secretion and proteolytic activity of MMP-3 were investigated using western blot analysis and casein zymography, respectively. The eff ect of prunetin on MMP-3 protein production was also examined in vivo. The results were as follows: (1) prunetin inhibited the gene expression of MMP-3, MMP-1, MMP-13, ADAMTS-4, and ADAMTS-5; (2) prunetin inhibited the secretion and proteolytic activity of MMP-3; (3) prunetin suppressed the production of MMP-3 protein in vivo. These results suggest that prunetin can regulate the gene expression, secretion, and proteolytic activity of MMP-3, by directly acting on articular chondrocytes.

Purpose: The aim of this study was to evaluate the correlation between the 3-dimensional (D) notch volume and the 2D notch width and notch shape as measured on magnetic resonance imaging (MRI), between subjects with anterior cruciate ligament (ACL) injury and those without ACL injury. Materials and Methods: Knee MRI images were taken from 72 subjects with ACL injury and 80 subjects without ACL injury (January 2007 to January 2012; Gyeongsang National University Hospital, Jinju, Korea). We measured 3D notch volume and 2D notch width and notch shape. The measured values from MRI figures between ACL-injured subjects and non-ACL-injured subjects were compared and analyzed. These measurements (notch width, notch ratio) were correlated to notch volume. Both intra-observer reliability and inter-observer reliability were calculated. Results: Notch width differed significantly between ACL injured subjects and non-injured subjects (p<0.001), while no significant differences in notch volume and notch shape were observed between the groups (male: p=0.43, female: p=0.22). Conclusion:The results of this study might suggest that certain 2D measurements (notch width) of the notch could be better than notch volume for prediction of ACL rupture risk.

Recently, several new techniques for anatomic posterior cruciate ligament reconstruction (PCLR) have emerged and are believed to restore the normal anatomy of the posterior cruciate ligament more accurately. Despite the latest trend, the optimal methods for anatomic PCLR remain controversial. The purpose of this research is to review surgical techniques for PCLR in cadaver studies and suggest consistent and reproducible technical criteria. For the review of the literature, MEDLINE and EMBASE were screened for articles on anatomic PCLR. Only basic science studies on PCLR performed on human cadavers and written in English were included. Seventeen studies were included in this systematic review. Only the tunnel positions, graft types, and surgical techniques were reported in the majority of the studies. There were many variations of the reported tunnel positions, graft types, and surgical techniques among the studies. In most studies, surgical techniques for consistent and reproducible anatomic PCLR were not explained clearly. Therefore, high level medical research should be encouraged in order to establish standard surgical techniques for anatomic PCLR.

Age-related rotator cuff tendon degeneration is related to tenofibroblast apoptosis. Anthocyanins reduce oxidative stress-induced apoptotic cell death in tenofibroblasts. The current study investigated the presence of cell protective effects in cyanidin and delphinidin, the most common aglycon forms of anthocyanins. We determined whether these anthocyanidins have antiapoptotic and antinecrotic effects in tenofibroblasts exposed to H2O2, and evaluated their biomolecular mechanisms. Both cyanidin and delphinidin inhibited H2O2-induced apoptosis in a dose-dependent manner. However, at concentrations of 100 μg/ml or greater, delphinidin showed cytotoxicity against tenofibroblasts and a decreased antinecrotic effect. Cyanidin and delphinidin both showed inhibitory effects on the H2O2-induced increase in intracellular ROS formation and the activation of ERK1/2 and JNK. In conclusion, both cyanidin and delphinidin have cytoprotective effects on cultured tenofibroblasts exposed to H2O2. These results suggest that cyanidin and delphinidin are both beneficial for the treatment of oxidative stress-mediated tenofibroblast cell death, but their working concentrations are different.

PurposeUpper extremity musculoskeletal disorders (UEMDs), such as rotator cuff tear, epicondylitis, and hand osteoarthritis, have a negative impact on quality of life (QOL). In this study, we evaluated the prevalence of rotator cuff tear, lateral and medial epicondylitis, and hand osteoarthritis in the dominant side and the impact of these UEMDs on the disabilities of the arm, shoulder, and hand (DASH) outcome measure, which assesses upper extremity-related QOL.Materials and MethodsIn 2013–2015, 987 participants from rural areas completed a questionnaire and underwent physical examinations, laboratory tests, simple radiographic evaluations of bilateral upper extremities, and magnetic resonance imaging studies of bilateral shoulders. Based on data from these participants, researchers evaluated DASH and performed a functional assessment of each region of the dominant side and related UEMDs.ResultsThe prevalences of epicondylitis, rotator cuff tear, and hand osteoarthritis were 33.7%, 53.4%, and 44.6%, respectively. Univariate regression analysis results revealed that epicondylitis, epicondylitis+rotator cuff tear, epicondylitis+hand osteoarthritis, and epicondylitis+rotator cuff tear+hand osteoarthritis were significantly associated with DASH score. Multiple regression analysis, including DASH, UEMD, and regional functional assessments, showed that only epicondylitis and epicondylitis+rotator cuff tear were associated with DASH score.ConclusionEpicondylitis significantly affected QOL, while other UEMDs, such as hand osteoarthritis and rotator cuff tear, had no significant impact. When a patient's QOL is affected by a UEMD, there is an increased possibility of the simultaneous presence of other UEMDs.

Purpose:The purpose of this study is to evaluate risk factors for wrist stiffness after treatment of distal radius fractures. Materials and Methods: A total of 55 consecutive patients who were diagnosed with distal radius fracture at the current authors' institution and followed-up for at least 6 months were included in this retrospective study. Data on all factors related to wrist stiffness were considered. The degree of association for each of the factors was determined by calculation of the odds ratio (OR), with a 95% confidence interval. Logistic regression analyses were performed. p-value was set below 0.05. Results: Among radiologic indexes reflecting the degrees of fracture reduction, only ulnar variance showed significant association with wrist stiffness of distal radius fracture (p＜0.05). In univariate analysis, age (p=0.037; OR, 1.051) and diabetes mellitus (DM) (p=0.016; OR, 8.000) showed significant association with wrist stiffness. Various factors significant at the p-value less than 0.20 level in univariate analyses were included in the multivariate analyses. In multivariate analyses, only DM (p=0.034; OR, 6.588) showed significant association with wrist stiffness. Conclusion: Contraction of DM is critical to avoid wrist stiffness of distal radius fracture patients. In addition, ulnar variance was considered a significant factor of wrist stiffness in distal radius fracture patients, thus reduction of fracture could be done more in proximity to normal anatomy.