Ns/purposes The aim of this study was to validate the MSTS scoring system for the upper extremity (MSTS-UE) in Japanese patients with musculoskeletal tumors for use by others in research. Does the MSTS-UE have: (1) sufficient reliability and internal consistency; (2) adequate construct validity; and (3) reasonable criterion validity in comparison to the Toronto Extremity Salvage Score (TESS) or SF-36? Methods Reliability was performed using test-retest analysis, and internal consistency was evaluated with Cronbach's alpha coefficient. Construct validity was evaluated using a scree plot to confirm the construct number and the Akaike information criterion network. Criterion validity was evaluated by comparing the MSTS-UE with the TESS and SF-36. Results The test-retest reliability with intraclass correlation coefficient (0.95; 95% CI, 0.91-0.97) was excellent, and internal consistency with Cronbach's α (0.7; 95% CI, 0.53-0.81) was acceptable. There were no ceiling and floor effects. The Akaike Information Criterion network showed that lifting ability, pain, and dexterity played central roles among the components. The MSTS-UE showed substantial correlation with the TESS scoring scale (r = 0.75; p < 0.001) and fair correlation with the SF-36 physical component summary (r = 0.37; p = 0.007). Although the MSTS-UE showed slight correlation with the SF-36 mental component summary, the emotional acceptance component of the MSTS-UE showed fair correlation (r = 0.29; p = 0.039). Conclusions We can conclude that the MSTS is not an adequate measure of general health-related quality of life; however, this system was designed mainly to be a simple measure of function in a single extremity. To evaluate the mental state of patients with musculoskeletal tumors in the upper extremity, further study is needed....

Lubricin encoded by the proteoglycan 4 (Prg4) gene is produced from superficial zone (SFZ) cells of articular cartilage and synoviocytes, which is indispensable for lubrication of joint surfaces. Loss‐of‐function of human and mouse Prg4 results in early‐onset arthropathy accompanied by lost SFZ cells and hyperplastic synovium. Here, we focused on increases in the thickness of articular cartilage in Prg4‐knockout joints and analyzed the underlying mechanisms. In the late stage of articular cartilage development, the articular cartilage was thickened at 2–4 weeks and the SFZ disappeared at 8 weeks in Prg4‐knockout mice. Similar changes were observed in cultured Prg4‐knockout femoral heads. Cell tracking showed that Prg4‐knockout SFZ cells at 1 week of age expanded to deep layers after 1 week. In in vitro experiments, overexpression of Prg4 lacking a mucin‐like domain suppressed differentiation of ATDC5 cells markedly, whereas pellets of Prg4‐knockout SFZ cells showed enhanced differentiation. RNA sequencing identified matrix metalloproteinase 9 (Mmp9) as the top upregulated gene by Prg4 knockout. Mmp9 expressed in the SFZ was further induced in Prg4‐knockout mice. The increased expression of Mmp9 by Prg4 knockout was cancelled by IκB kinase (IKK) inhibitor treatment. Phosphorylation of Smad2 was also enhanced in Prg4‐knockout cell pellets, which was cancelled by the IKK inhibitor. Expression of Mmp9 and phosphorylated Smad2 during articular cartilage development was enhanced in Prg4‐knockout joints. Lubricin contributes to homeostasis of articular cartilage by suppressing differentiation of SFZ cells, and the nuclear factor‐kappa B‐Mmp9‐TGF‐β pathway is probably responsible for the downstream action of lubricin.

Has not yet been validated. Questions/purpose We sought to determine whether a Japanese-language translation of the MSTS scoring system for the lower extremity had (1) sufficient reliability and internal consistency, (2) adequate construct validity, and (3) reasonable criterion validity compared with the Toronto Extremity Salvage Score (TESS) and SF-36 using psychometric analysis. Methods The Japanese version of the MSTS scoring system was developed using accepted guidelines, which included translation of the English version of the MSTS into Japanese by five native Japanese bilingual musculoskeletal oncology surgeons and integrated into one document. One hundred patients with a diagnosis of intermediate or malignant bone or soft tissue tumors located in the lower extremity and who had undergone tumor resection with or without reconstruction or amputation participated in this study. Reliability was evaluated by test-retest analysis, and internal consistency was established by Cronbach's alpha coefficient. Construct validity was evaluated using the principal factor analysis and Akaike information criterion network. Criterion validity was evaluated by comparing the MSTS scoring system with the TESS and SF-36. Results Test-retest analysis showed a high intraclass correlation coefficient (0.92; 95% CI, 0.88-0.95), indicating high reliability of the Japanese version of the MSTS scoring system, although a considerable ceiling effect was observed, with 23 patients (23%) given the maximum score. Cronbach's alpha coefficient was 0.87 (95% CI, 0.82-0.90), suggesting a high level of internal consistency. Factor analysis revealed that all items had high loading values and communalities; we identified a central role for the items “walking” and “gait” according to the Akaike information criterion network. The total MSTS score was correlated with that of the TESS (r = 0.81; 95% CI, 0.73-0.87; p < 0.001) and the physical component summary and physical functioning of the SF-36. Conclusions The Japanese-language translation of the MSTS scoring system for the lower extremity has sufficient reliability and reasonable validity. Nevertheless, the observation of a ceiling effect suggests poor ability of this system to discriminate from among patients who have a high level of function....

Necrotising soft-tissue infections (NSTIs) of the upper limb are uncommon, but potentially life-threatening. We used a national database to investigate the risk factors for amputation of the limb and death. We extracted data from the Japanese Diagnosis Procedure Combination database on 116 patients (79 men and 37 women) who had a NSTI of the upper extremity between 2007 and 2010. The overall in-hospital mortality was 15.5%. Univariate analysis of in-hospital mortality showed that the significant variables were age (p = 0.015), liver dysfunction (p = 0.005), renal dysfunction (P < 0.001), altered consciousness (p = 0.049), and sepsis (p = 0.021). Logistic regression analysis showed that the factors associated with death in hospital were age over 70 years (Odds Ratio (OR) 6.6; 95% confidence interval (CI) 1.5 to 28.2; p = 0.011) and renal dysfunction (OR 15.4; 95% CI 3.8 to 62.8; p < 0.001). Univariate analysis of limb amputation showed that the significant variables were diabetes (p = 0.017) mellitus and sepsis (p = 0.001). Multivariable logistic regression analysis showed that the factors related to limb amputation were sepsis (OR 1.8; 95% CI 1.5 to 24.0; p = 0.013) and diabetes mellitus (OR 1.6; 95% CI 1.1 to 21.1; p = 0.038). For NSTIs of the upper extremity, advanced age and renal dysfunction are both associated with a higher rate of in-hospital mortality. Sepsis and diabetes mellitus are both associated with a higher rate of amputation. Cite this article: Bone Joint J 2014;96-B:1530–4.