Objectives. Metabolic syndrome and low-grade systemic inflammation are associated with knee osteoarthritis (OA), but the relationships between these factors and OA in other synovial joints are unclear. The aim of this study was to determine if a high-fat/high-sucrose (HFS) diet results in OA-like joint damage in the shoulders, knees, and hips of rats after induction of obesity, and to identify potential joint-specific risks for OA-like changes. Methods. A total of 16 male Sprague-Dawley rats were allocated to either the diet-induced obesity group (DIO, 40% fat, 45% sucrose, n = 9) or a chow control diet (n = 7) for 12 weeks. At sacrifice, histological assessments of the shoulder, hip, and knee joints were performed. Serum inflammatory mediators and body composition were also evaluated. The total Mankin score for each animal was assessed by adding together the individual Modified Mankin scores across all three joints. Linear regression modelling was conducted to evaluate predictive relationships between serum mediators and total joint damage. Results. The HFS diet, in the absence of trauma, resulted in increased joint damage in the shoulder and knee joints of rats. Hip joint damage, however, was not significantly affected by DIO, consistent with findings in human studies. The total Mankin score was increased in DIO animals compared with the chow group, and was associated with percentage of body fat. Positive significant predictive relationships for total Mankin score were found between body fat and two serum mediators (interleukin 1 alpha (IL-1α) and vascular endothelial growth factor (VEGF)). Conclusion. Systemic inflammatory alterations from DIO in this model system may result in a higher risk for development of knee, shoulder, and multi-joint damage with a HFS diet. Cite this article: K. H. Collins, D. A. Hart, R. A. Seerattan, R. A. Reimer, W. Herzog. High-fat/high-sucrose diet-induced obesity results in joint-specific development of osteoarthritis-like degeneration in a rat model. Bone Joint Res 2018;7:274–281. DOI: 10.1302/2046-3758.74.BJR-2017-0201.R2

Introduction and Objective. Carpal tunnel syndrome (CTS) is a very common compressive neuropathy involving the median nerve. The typical symptoms are paraesthesia, dysesthesia and loss of strength; in severe case, this compression deteriorates the sensorimotor control of the hand and interferes with the adjustment of the forces at the level of the fingers, thus affecting the components that are the basis of dexterity and control of fine movements. For these reasons, the CTS has repercussions on various activities of daily life, including writing skills. Word processing via PC and mobile device (touch-typing) require a fine control of the hand-wrist movement and of the opposition of the thumb, while in handwriting, gripping and gripping movements are carried out in a protracted manner. In modern society, present skills play a role of fundamental importance from an educational, professional and social point of view. The aim of the study is to describe the effects of carpal tunnel release (CTR) on handwriting and digital writing performance. Materials and Methods. We recruited patients suffering from carpal tunnel syndrome (CTS) who were candidates for CTR surgery and collected clinical and demographic data, including age, occupation, duration of symptoms and electromyography outcomes. The first trial session was carried out before surgery and the subsequent ones at 1, 2, 3, 4, 8 and 12 weeks after the CTR. These trials involved copying a 500-character paragraph by handwriting, personal computer (PC) and mobile device, for which a dedicate Google Colab web page was computed. We used as parameters the speed, expressed in words per minute (wpm), and the accuracy of copying, which was measured in number of errors (en). Moreover in each session the patient filled in the QuickDASH (Disabilities of the Arm, Shoulder, and Hand) questionnaire. We used the one-way anova to evaluate the change in the three performances and in the QuickDASH score in follow-up sessions. We used the two-way anova to detect a possible interactions between speed improvement and groups of variables, namely gender, writing frequency, schooling, diabetes, dysthyroidism and metabolic syndrome. Results. We recruited 20 patients of whom 7 dropped out for personal reasons and 13 had completed all trial sessions. The PC writing performance had an average speed and accuracy of 15.1 ± 6.8 wpm and 13.1 ± 8.2 en, respectively, while post-operatively it returned values of 17.6 ± 5.0 wpm and 9.9 ± 5.6 en. Regarding touch-typing, a pre-operative average of 16.9 ± 5.8 wpm and 14.3 ± 14.4 en was recorded, while post-operatively an average of 21.7 ± 6.5 wpm and 11.5 ± 14.7 en was reported. Handwriting performance initially had a mean of 20.5 ± 7.1 wpm and 0.1 ± 0.6 en and after three months returned a mean of 22.4 ± 4.0 wpm and 0 ± 0 n. The QuickDASH score had a pre-operative mean of 39.1 ± 9.1 and post-operative mean of 17 ± 6 points. The only statistically significant improvements were those related to touch-typing (P = 0.022) and QuickDASH score (P < 0.001). There was no significant interaction between gender, comorbidity, writing frequency, level of schooling and recovery of writing ability. Conclusions. The data collected showed, in agreement with previous studies, that CTS has a significant impact on the patient's writing ability, who benefits from the surgical treatment, especially in terms of touch-typing and general manual dexterity. In addition, the recovery of writing ability did not show significant correlation with other variables