To determine the risk of total knee replacement (TKR) for primary osteoarthritis (OA) associated with overweight/obesity in the Australian population. This population-based study analyzed 191,723 cases of TKR collected by the Australian Orthopaedic Association National Joint Registry and population data from the Australian Bureau of Statistics. The time-trend change in incidence of TKR relating to BMI was assessed between 2015-2018. The influence of obesity on the incidence of TKR in different age and gender groups was determined. The population attributable fraction (PAF) was then calculated to estimate the effect of obesity reduction on TKR incidence. The greatest increase in incidence of TKR was seen in patients from obese class III. The incidence rate ratio for having a TKR for obesity class III was 28.683 at those aged 18-54 years but was 2.029 at those aged >75 years. Females in obesity class III were 1.7 times more likely to undergo TKR compared to similarly classified males. The PAFs of TKR associated with overweight or obesity was 35%, estimating 12,156 cases of TKR attributable to obesity in 2018. The proportion of TKRs could be reduced by 20% if overweight and obese population move down one category. Obesity has resulted in a significant increase in the incidence of TKR in the youngest population in Australia. The impact of obesity is greatest in the young and the female population. Effective strategies to reduce the national obese population could potentially reduce 35% of the TKR, with over 10,000 cases being avoided

Abstract. Objectives. Obesity is prevalent with nearly one third of the world's population being classified as obese. Total knee arthroplasty (TKA) is an effective treatment option for high BMI patients achieving similar outcomes to non-obese patients. However, increased rates of aseptic loosening in patients with a high BMI have been reported. In patients with high BMI/body mass there is an increase in strain placed on the implant fixation interfaces. As such component fixation is a potential concern when performing TKA in the obese patient. To address this concern the use of extended tibial stems in cemented implants or cementless fixation have been advocated. Extend tibial stems are thought to improve implant stability reducing the micromotion between interfaces and consequently the risk of aseptic loosening. Cementless implants, once biologic fixation is achieved, effectively integrate into bone eliminating an interface. This retrospective study compared the use of extended tibial stems and cementless implants to conventional cemented implants in high BMI patients. Methods. From a prospectively maintained database of 3239 primary Attune TKA (Depuy, Warsaw, Indiana), obese patients (body mass index (BMI) >30 kg/m²) were retrospectively reviewed. Two groups of patients 1) using a tibial stem extension [n=162] and 2) cementless fixation [n=163] were compared to 3) a control group (n=1426) with a standard tibial stem cemented implant. All operations were performed by or under the direct supervision of specialist arthroplasty surgeons. Analysis compared the groups with respect to class I, II, and III (BMI >30kg/m², >35 kg/m², >40 kg/m²) obesity. The primary outcome measures were all-cause revision, revision for aseptic loosening, and revision for tibial loosening. Kaplan-Meier survival analysis and Cox regression models were used to compare the primary outcomes between groups. Where radiographic images at greater than 3 months post-operatively were available, radiographs were examined to compare the presence of peri-implant radiolucent lines. Results. The mean follow-up of 4.8, 3.4, and 2.5 years for cemented, stemmed, and cementless groups respectively. In total there were 34 all-cause revisions across all the groups with revision rates of 4.55, 5.50, and 0.00 per 1000-implant-years for cemented, stemmed, and cementless groups respectively. Survival Analysis did not show any significant differences between the three groups for all-all cause revision. There were 6 revisions for aseptic loosening (5 tibial and 1 femoral); all of which were in the standard cemented implant group. In contrast there were no revisions in the stemmed or cementless implant groups, however, this was not significant on survival analysis. Analysis looking at class I, II, and III obesity also did not show any significant differences in survival for all cause revision or aseptic loosening. Conclusion. This retrospective analysis showed that there were no revisions required for aseptic loosening when either a cemented stemmed or cementless implant were used in obese patients. These findings are in line with other studies showing that cementless fixation or extended stem implants are a reasonable option in obese patients who represent an increasing cohort of patients requiring TKR. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Obesity is associated with poor outcomes and increased risk of failure after rotator cuff (RC) repair surgery. The effect of diet-induced obesity (DIO) on enthesis healing has not been well characterised and whether its effects can be reversed with dietary intervention is unknown. We hypothesised that DIO would result in inferior enthesis healing in a rat model of RC repair and that dietary intervention in the peri-operative period would improve enthesis healing. A total of 78 male Sprague-Dawley rats were divided into three weight-matched groups from weaning and fed either: control diet (CD), high-fat diet (HFD), or HFD until surgery, then CD thereafter (HF-CD). After 12 weeks the left supraspinatus tendon was detached, followed by immediate surgical repair. At 2 and 12 weeks post-surgery, animals were cullers and RCs harvested for biomechanical and histological evaluation. Body composition and metabolic markers were assessed via DEXA and plasma analyses, respectively. DIO was established in the HFD and HF-CD groups prior to surgery, and subsequently reversed in the HF-CD group after surgery. At 12 weeks post-surgery, plasma leptin concentrations were higher in the HFD group compared to the CD group (5.28 vs. 2.91ng/ml, P=0.003). Histologically, the appearance of the repaired entheses was poorer in both the HFD and HF-CD compared to the CD group at 12 weeks (overall histological score 6.20 (P=0.008), 4.98 (P=0.001) and 8.68 out of 15, respectively). The repaired entheses in the HF-CD group had significantly lower (26.4 N, P=0.028) load-at-failure 12 weeks post-surgery compared to the CD group (34.4 N); while the HFD group was low, but not significantly different (28.1 N, P=0.096). Body mass at the time of surgery, plasma leptin and body fat percentage were negatively correlated with histological scores and plasma leptin with load-at-failure 12 weeks post-surgery. DIO impaired enthesis healing in this rat RC repair model, with inferior biomechanical and histological outcomes. Restoring normal weight with dietary change after surgery did not improve healing outcomes. Exploring interventions that improve the metabolic state of obese patients and counselling patients appropriately about their modest expectations after repair should be considered

Obese patients show a higher incidence of tendon-related pathologies. These patients present a low inflammatory systemic environment and a higher mechanical demand which can affect the tendons. In addition, inflammation might have a role in the progression of the disease as well as in the healing process. A systematic review was performed by searching PubMed, Embase and Cochrane Library databases. Inclusion criteria were studies of any level of evidence published in peer-reviewed journals reporting clinical or preclinical results. Evaluated data were extracted and critically analysed. PRISMA guidelines were applied, and risk of bias was assessed, as well as the methodological quality of the included studies. We excluded all the articles with high risk of bias and/or low quality after the assessment. Due to the high heterogeneity present among the studies, a metanalysis could not be done. Thus, a descriptive analysis was performed. After applying the previously described criteria, thirty articles were included, assessed as medium or high quality. We analysed the data of 50865 subjects, 6096 of which were obese (BMI over 30 accordingly to the WHO criteria). The overall risk of re-tear after surgery is about the 10% more than normal BMI subjects. The rupture risk fluctuates in the studies without showing a significant trend. Obese subjects have a higher risk to develop tendinopathy and a worse outcome after surgery as confirmed in several human studies. The obesity influence on tendon structure and mechanical properties may rely on the fat tissue endocrine proprieties and on hormonal imbalance. Clinicians should consider obesity as a predisposing factor for the development of tendinopathies and for a higher risk of complications in patients who underwent surgical repair of tendons

Osteoarthritis is one of the major causes of immobility. Most commonly, osteoarthritis manifests at the knee joint. Prevalence of knee osteoarthritis (KNOA) increases with age. Another important risk factor for KNOA is obesity. Research has shown that obese subjects have almost four times the risk of developing KNOA, which may be explained by both an increased knee loading. In medial compartment KNOA, the knee adduction moment (KAM) during gait is considered a marker for disease severity. KAM is dependent of the magnitude of the ground reaction force and its moment arm relative to the knee joint centre. In addition, obesity has been reported to augment KAM during gait. However, after removal of the direct contributions of body weight, KAM parameters may be different due to obesity-related gait adaptations to limit knee loading. While KAM has been thoroughly investigated during gait, little is known about KAM during stair negotiation, during which knee loads are higher compared to gait. The aim of the current study is therefore to compare normalized KAM during the stance phase of stair negotiation between lean KNOA patients, obese KNOA patients, and healthy controls. This case control study included 20 lean controls, 14 lean KNOA patients, and 16 obese KNOA patients. All subjects ascended and descended a two-step staircase at a self-selected, comfortable speed. Radiographic imaging and MRI were used to evaluate knee cartilage and KNOA status. Motion analysis was performed with a three-dimensional motion capture system. Kinetic data were obtained by one force platform. The parameters of study included: stance phase duration, toe-out angle, KAM peaks and KAM impulse. During stair ascent obese KNOA patients showed a longer stance phase than healthy controls (P 0.050). Despite high between-subject variability, KAM impulse was found 45% higher in the obese KNOA group during stair descent, when compared to healthy controls (P =0.012). The absence of a significant effect of groups on the normalized KAM during stair negotiation may be explained by a lower ambulatory speed in the obese KNOA group, that effectively lowers GRFz. Decreasing ambulatory speed may be an effective strategy to lower KAM during stair negotiation

Objectives. Given the function of adiponectin (ADIPOQ) on the inflammatory condition of obesity and osteoarthritis (OA), we hypothesized that the ADIPOQ gene might be a candidate gene for a marker of susceptibility to OA. Methods. We systematically screened three tagging polymorphisms (rs182052, rs2082940 and rs6773957) in the ADIPOQ gene, and evaluated the association between the genetic variants and OA risk in a case-controlled study that included 196 OA patients and 442 controls in a northern Chinese population. Genotyping was performed using the Sequenom MassARRAY iPLEX platform. Results. The single nucleotide polymorphism (SNP) rs182052 was found to be potentially associated with knee OA risk (additive model: odds ratio = 1.38; 95% confidence interval 1.07 to 1.76; p = 0.012). Furthermore, a non-significant association was observed for rs182052 and body mass index with regard to OA risk in interaction analyses (p = 0.063). Similarly, no significant interaction was detected for rs182052 and age with regard to OA risk (p = 0.614). Conclusion. These findings suggest that the SNP rs182052 in the ADIPOQ gene may potentially modify individual susceptibility to knee OA in the Chinese population. Further studies are warranted to investigate our findings in more depth. Cite this article: L. Jiang, X. Zhu, J. Rong, B. Xing, S. Wang, A. Liu, M. Chu, G. Huang. Obesity, osteoarthritis and genetic risk: The rs182052 polymorphism in the ADIPOQ gene is potentially associated with risk of knee osteoarthritis. Bone Joint Res 2018;7:494–500. DOI: 10.1302/2046-3758.77.BJR-2017-0274.R1

Obesity decreases patellar tendon stiffness in females but not males Introduction Patellar tendon (PT) injuries are frequent due to excessive mechanical loading during strenuous physical activity. PT injury incidence is higher in females and obese individuals. The reason behind higher tendon injury incidence in females and obese individuals might be structural changes in tendons such as stiffness or elasticity. Tendon stiffness can recently be quantified using shear wave elastography (SWE). We aimed to examine the stiffness of PT in healthy sedentary participants using this new technology. This prospective study was carried out with 58 (34 female, 24 male) healthy sedentary participants between the ages of 18–44 years (27.5±7.7 years). Body mass and body fat percentage were measured with the Bioelectrical Impedance method using Tanita BC-418 MA Segmental Body Composition Analyser (Tanita Corporation, Tokyo, Japan). Participants were subsequently categorized into ‘normal-weight’ (BMI < 23 kg/m2) and ‘obese’ (BMI>27.5 kg/m2). SWE of the PT was measured with the ACUSON S3000 (Siemens Medical Solution, Mountain Wiew, CA, USA) ultrasound device using the Siemens 9L4 (4–9 MHz) linear-array probe with the Virtual Touch Imaging Quantification® method. The measurement was performed by placing the US probe longitudinally on patellar tendon with knee flexed at 30°. The region between about 1 cm distal of patellar bone-tendon junction and 1 cm proximal of bone-tendon junction of tibia was used for PT stiffness measurement (Figure 1). Average of three successive measurements at 10 sec intervals was recorded as PT stiffness. PT stiffness was quantified with MATLAB Version 2015 (Mathworks, Massachusetts, USA) by converting colour data into numbers. PT stiffness, in males, in females, in normal males, in obese males, in normal females, and in obese females was 8.6±1.0 m/sec, 7.4±1.1 m/sec, 8.6±1.1 m/sec, 8.5±1.0 m/sec, 7.9±0.9 m/sec, and 6.2±0.9 m/sec, respectively. Average body fat percentage in males, in females, in normal males, in obese males, in normal females, and in obese females was 20.1±7.4 kg/m2, 30.1±8.1 kg/m2, 15.4±5.2 kg/m2, 24.7±4.6 kg/m2, 25.6±5.5 kg/m2, and 38.1±5.0 kg/m2, respectively. Males PT stiffness was higher when compared to that of females (p=0.000). PT stiffness was similar in obese and normal males (p=0.962) but obese females had lower PT stiffness compared to normal females (p=0.001). PT stiffness of females was lower than males and obesity decreased PT stiffness in females but not in males. The possible explanation of lower PT stiffness in females might be due to their higher estrogen levels that lead to a decrease in estradiol level and collagen synthesis. Lower tendon stiffness in obese females might be metabolic effects due to the increased adipose tissue that contains proteins such as adipokinome, chemerin, lipocalin 2, serum amyloid A3 and adiponectin. These proteins lead to disturbance of tendon homeostasis and decreased collagen content. Altered tendon homeostasis and decreased collagen content may lead to a decrease in tendon stiffness. Decreased PT stiffness in especially in obese women might be associated with increased risk of PT injury

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

The purpose of this study was to evaluate the effect of body mass index (BMI) on patients undergoing primary total knee arthroplasty for osteoarthritis. Data was collected on 664 patients at 4 centres all of whom received a Depuy PFC Sigma prosthesis. Data collected included patient demographics, Oxford Knee Score (OKS), American Knee Society Score, SF-12, complications of surgery and the need for revision. 14% of patients had a BMI<25, 35% were overweight (BMI-25–30), 32% suffered from Grade 1 obesity (BMI-30–35) and 19% had grade 2 obesity (BMI>35). Obese patients were more likely to be female, have a higher ASA grade, present at a younger age and do sedentary work or no work at all. Pre-operative Oxford knee score was significantly worse in the BMI>35 group (p<0.001). After surgery there was a significant improvement in functional outcome measures at 5 years post-operatively with all BMI groups improved by an average of 18 or 19 points in the OKS. However because those patients with high BMI have poorer pre-operative Oxford scores their post-operative scores were lower compared to patients with a normal BMI. Similar findings were noted with range of motion of the knee joint. Overall complication rates were found to be significantly higher in obese patients and both revision surgery and deep infection rates increased stepwise with increasing BMI levels. Deep Infection rates were as follows: BMI<25 0%, BMI-25–30 1.3%, BMI-30–35 1.4%, BMI-35–40 3.2% and BMI>40 6.1%. Revision rates were as follows: BMI<25 0%, BMI-25–30 0.9%, BMI-30–35 0.9%, BMI-35–40 3.2% and BMI>40 6.1%. Although obese patients with knee osteoarthritis do benefit from joint arthroplasty, they suffer from an increased rate of complications and need for revision surgery

Obese patients undergoing total knee arthroplasty (TKA) face increased risks of complications such as joint infection and early revision. However, the influence of obesity on measures of patient function following TKA is poorly defined. Knee arthroplasty outcome data for procedures carried out over an eight month period was extracted from a regional database in the UK. We analysed the impact of weight categories (BMI<30, BMI=30–34.9, and BMI≥35) on the Forgotten Joint Score – 12 (FJS-12) and Oxford Knee Score (OKS). Data was available preoperatively and 12 months postoperatively. Physical and mental health was assessed with the SF-12 one year after surgery. Data from 256 patients were available. 49.6% had a BMI<30, 27.4% had a BMI 30–34.9 and 23.1% had a BMI≥35. Mean FJS-12 results at 1-year were 48.7 points for patients with a BMI<30, 40.7 points for patients with a BMI=30–34.9 and 34.0 points for patients with a BMI≥35. Effect sizes for change from baseline to 12-month post-op were 3.0 (Cohen's d) in patients with BMI<30 and d=2.2 in patients with BMI≥35. Mean OKS results at 1 year were 36.9 (BMI<30), 33.7 (BMI=30–34.9) and 32.0 (BMI≥35) respectively. Effect sizes for change from baseline to 12-month was d=2.1 (BMI<30) and d=1.9 (BMI≥35). Differences between BMI groups with regard to post-operative change were statistically significant for the FJS-12 (p=0.038) but not for the OKS (p=0.229). This study highlights that outcome scores may differ in their ability to capture the impact of obesity on patient function following TKA. The FJS-12 showed significant differences in outcome based on patient obesity category, whereas the OKS did not detect between group differences

Two major challenges in arthroplasty are obesity and antibiotic resistance. This study was performed to characterise the organisms responsible for deep infection following total hip arthroplasty and to determine if obesity affected the microbiology profile. A retrospective analysis of the national surgical site infection register was made to obtain data regarding deep infection following 10948 primary total hip arthroplasty (THA) from 1998–2013, with a minimum of 2 year follow-up. Of all the primary THAs performed, there were 108 deep infections (56 patients had a BMI >30 (obese) and 52 patients <30). There were no significant differences between cardio-respiratory disease, smoking and alcohol status, and diabetes between the 2 groups. Over the last 15 years, staphylococcus aureus continues to be the most frequently isolated organism. Infection with multiple organisms was found exclusively in obese patients. Furthermore, in obese patients, there was a linear increase with methicillin resistant staphylococcus aureus (MRSA) infections and streptococcus viridans. On this basis, we recommend careful selection of antibiotic therapy in obese patients, rather than empirical therapy, which can be especially important if there is no growth in an infected THA. In addition, a preoperative discussion regarding dental prophylaxis against streptococcus viridans may be warranted

Introduction. Precision error (PE) in Dual Energy X-Ray Absorptiometry (DXA) is important for accurate monitoring of changes in Bone-Mineral-Density (BMD). It has been demonstrated that BMD PE increases with increasing BMI. In vivo PE for the Trabecular-Bone-Score (TBS) has not been reported. This study aimed to evaluate the short-term PE (STPE)) of BMD and TBS and to investigate the effect of obesity on DXA PE. Method. DXA lumbar spine scans (L1–L4) were performed using GE Lunar Prodigy. STPE was measured in 91 women (Group A) at a single visit by duplicating scans with repositioning in-between. PE was calculated as the percentage coefficient of variation (%CV). Group A was sub-divided into four groups based on BMI (A.1. <25kg/m2, A.2. 25–29.9kg/m2, A.3. 30–35kg/m2 and A.4. >35kg/m2) to assess the effect of obesity on STPE. Abnormally different vertebrae were excluded from the analysis in accordance with The International Society for Clinical Densitometry (ISCD) recommendations. Results. The Group A STPE was 1.26 % for BMD and 2.04% for TBS. Short-term PE for BMD and TBS respectively in the BMI subgroups was: A.1. 1.07% and 1.82%, A.2. 1.34% and 2.26%, A.3. 1.25% and 2.35%, A.4. 1.68% and 1.82%. Conclusion. The results show that STPE is higher for TBS than for BMD. Short-term PE for both BMD and TBS are adversely affected by increasing BMI but this effect is mitigated in the highest BMI category where use of the ‘thick’ scanning mode improves signal to noise ratio

Osteoarthritis (OA) of the knee joint is a complex peripheral joint disorder with multiple risk factors. We aimed to examine the relationship between the grade of knee OA and anterior thigh length (ATL). A total of 64 geriatric patients who had no total hip or knee replacement with a BMI of ≥30 were evaluated. Patients' OA severity was determined by two independent experts from bilateral standing knee radiographs according to the Kellgren-Lawrence (KL) grade. Joint cartilage structure was assessed using ultrasonography (US). The ATL, the gastrocnemius medialis (GC), the rectus femoris (RF) and the rectus abdominis (RA) skeletal muscle thicknesses as well as the RF cross-sectional area (CSA) were measured with US. Sarcopenia was diagnosed using the handgrip strength (HGS), 5× sit-to-stand test (5xSST) and bioelectrical impedance analysis. The median (IQR) age of participants was 72 (65–88) years. Seventy-one per cent of the patients (n=46) were female. They were divided into the sarcopenic obese (31.3 %) and the non-sarcopenic obese (68.8%) groups. KL grade of all patients correlated negatively with the ATL (mm) and the thickness of GC (mm) (r= -0,517, p<0.001 and r= -0.456, p<0.001, respectively). In the sarcopenic obese and the non-sarcopenic obese groups, KL grade of the all patients was negatively correlated with ATL (mm) and thickness of GC (mm) (r= -0,986, p<0.001; r= -0.456, p=0.05 and r= -0,812, p=0.002; r= −0,427, p=0.006). KL grade negatively correlated with the RF thickness in the sarcopenic obese group (r= -0,928, p=0.008). In conclusion, OA risk may decrease as the lower extremity skeletal muscle mass increases. Acknowledgments: Feza Korkusuz MD is a member of the Turkish Academy of Sciences (TÜBA)

Obesity is correlated with the development of osteoporotic diseases. Gut microbiota-derived metabolite trimethylamine-n-oxide (TMAO) accelerates obesity-mediated tissue deterioration. This study was aimed to investigate what role TMAO may play in osteoporosis development during obesity. Mice were fed with high-fat diet (HFD; 60 kcal% fat) or chow diet (CD; 10 kcal% fat) or 0.2% TMAO in drinking water for 6 months. Body adiposis and bone microstructure were investigated using μCT imaging. Gut microbiome and serum metabolome were characterized using 16S rRNA sequencing and liquid chromatography-tandem mass spectrometry. Osteogenic differentiation of bone-marrow mesenchymal cells was quantified using RT-PCR and von Kossa staining. Cellular senescence was evaluated by key senescence markers p16, p21, p53, and senescence association β-galactosidase staining. HFD-fed mice developed hyperglycemia, body adiposis and osteoporosis signs, including low bone mineral density, sparse trabecular microarchitecture, and decreased biomechanical strength. HFD consumption induced gut microbiota dysbiosis, which revealed a high Firmicutes/Bacteroidetes ratio and decreased α-diversity and abundances of beneficial microorganisms Akkermansiaceae, Lactobacillaceae, and Bifidobacteriaceae. Serum metabolome uncovered increased serum L-carnitine and TMAO levels in HFD-fed mice. Of note, transplantation of fecal microbiota from CD-fed mice compromised HFD consumption-induced TMAO overproduction and attenuated loss in bone mass, trabecular microstructure, and bone formation rate. TMAO treatment inhibited trabecular and cortical bone mass and biomechanical characteristics; and repressed osteogenic differentiation capacity of bone-marrow mesenchymal cells. Mechanistically, TMAO accelerated mitochondrial dysfunction and senescence program, interrupted mineralized matrix production in osteoblasts. Gut microbial metabolite TMAO induced osteoblast dysfunction, accelerating the development of obesity-induced skeletal deterioration. This study, for the first time, conveys a productive insight into the catabolic role of gut microflora metabolite TMAO in regulating osteoblast activity and bone tissue integrity during obesity

Introduction and Objective. Global prevalence of obesity has risen almost three-fold between 1975 and 2016. Alongside the more well-known health implications of obesity such as cardiovascular disease, cancer and type II diabetes, is the effect of male obesity on testosterone depletion and hypogonadism. Hypogonadism is a well-known contributor to the acceleration of bone loss during aging, and obesity is the single biggest risk factor for testosterone deficiency in men. Understanding the micro and macro structural changes to bone in response to testosterone depletion in combination with a high fat ‘Western’ diet, will advance our understanding of the relationship between obesity and bone metabolism. This study investigated the impact of surgically induced testosterone depletion and subsequent testosterone treatment upon bone remodelling in mice fed a high fat diet. Materials and Methods. Male ApoE. −/−. mice were split into 3 groups at 7 weeks of age and fed a high fat diet: Sham surgery with placebo treatment, orchiectomy surgery with placebo treatment, and orchiectomy surgery with testosterone treatment. Surgeries were performed at 8 weeks of age, followed by fortnightly testosterone treatment via injection. Mice were sacrificed at 25 weeks of age. Tibiae were collected and scanned ex-vivo at 4.3μm on a SkyScan 1272 Micro-CT scanner (Bruker). Left tibiae were used for assessment of trabecular and cortical Volumes of Interest (VOIs) 0.2mm and 1.0mm respectively from the growth-plate bridge break. Tibiae were subsequently paraffin embedded and sectioned at 4μm prior to immunohistochemical evaluation of alkaline phosphatase. Results. Trabecular bone volume and mineral density were significantly reduced in orchiectomised mice compared to sham-operated controls; and these parameters were normalised to control levels in orchiectomised mice treated with testosterone. In contrast, Trabecular thickness was significantly higher in testosterone depleted animals. Cortical bone parameters and body weights did not significantly differ between groups. Levels of alkaline phosphatase did not differ significantly in cortical or trabecular osteoblasts between groups. Conclusions. Findings suggest that testosterone deficiency significantly reduces trabecular bone parameters, and testosterone therapy may be a useful intervention for the loss of bone mass in testosterone deficient males. These results indicate that testosterone therapy may be useful for the treatment of trabecular bone frailty in testosterone deficient males. Observed changes in trabecular bone do not appear to be due to decreased mineralisation caused by osteoblast alkaline phosphatase. Ongoing work includes histology analysis to elucidate the mechanisms underpinning the changes seen in the bones of testosterone deficient animals

Introduction and Objective. Type 2 diabetes mellitus (T2DM), and the often concurrent obesity, causes metabolic changes that affect many organs and tissues, including bone. Despite a normal or even higher bone mineral density (BMD), T2DM has often been associated with a higher fracture risk, indicating a compromised bone quality. In this work, we use a novel congenic leptin receptor-deficient BioBreeding Diabetes Resistant rat (BBDR.cg.lepr.cp) to investigate the impact of T2DM and obesity on bone morphology and architecture at the microscale. Materials and Methods. Two different anatomical locations, i.e., femur and cranium, were studied combining micro-computed X-ray tomography (micro-CT) with scanning electron microscopy (SEM). Micro-CT data were examined using advanced image analysis tools in three-dimensions (3D). Results. Both parietal bones and femurs were smaller, i.e., thinner and shorter, respectively, in diabetic animals compared to healthy controls. Image analysis of the sagittal suture revealed a reduced suture width and length in diabetic animals, suggesting an altered bone apposition rate. Histomorphometry analysis from micro-CT data highlighted differences in microstructure of both trabecular and cortical femur between diabetic and healthy rats. In particular, bone volume fraction (BV/TV) was lower in the T2DM group, while trabecular spacing (Tb.Sp) was increased, overall indicating a higher porosity in diabetic trabecular bone. SEM revealed the presence of extended portions of hyper-mineralized cartilage in the distal femur of the diabetic animals. Conclusions. Micro-CT analyses, combined with SEM imaging, suggest that T2DM impacts bone growth and remodelling, in turn leading to differences in the structural organization at the microscale

Introduction. Many patients with obesity experience knee pain. Excess body weight is a modifiable risk factor for osteoarthritis (OA) and weight loss is encouraged in patients with OA. Bariatric surgery could improve or limit the progression of these conditions through significant weight loss. The Oxford Knee Score (OKS) is a validated tool in the assessment of knee replacement surgery for OA. We present a novel application of the OKS to assess knee pain & function after weight loss surgery. The primary aim of this study was to assess whether there was a significant difference in mean OKS before and 24 months after weight loss surgery. Method. Eighteen female participants were included in this study. They underwent sleeve gastrectomy or Roux-en-Y gastric bypass. Patient demographics, body mass index (BMI) and OKS were collected pre- and 24 months post operatively. Result. There was an increase in the mean OKS from 31.8 (SD 11.8) pre surgery to 36.6 (SD 12.3) at 24 months. This was statistically significant (95% CI 0.99-10.5, p=0.02). Mean BMI reduced from 46.6 kg/m. 2. (SD 5.8) to 33.0 kg/m. 2. (SD 3.5). Conclusion. A significant improvement in mean OKS was seen after weight loss surgery. These findings demonstrate an improvement in knee pain & function with weight loss. This study contributes to a larger project evaluating the kinetic and kinematic changes to walking gait from weight loss

Cervical spine facet tropism (CFT) defined as the facets’ joints angles difference between right and left sides of more than 7 degrees. This study aims to investigate the relationship between cervical sagittal alignment parameters and cervical spine facets’ tropism. A retrospective cross-sectional study carried out in a tertiary center where cervical spine magnetic resonance imaging (MRI) radiographs of patients in orthopedics/spine clincs were included. They had no history of spine fractures. Images’ reports were reviewed to exclude those with tumors in the c-spine. A total of 96 patients was included with 63% of them were females. The mean of age was 45.53± 12.82. C2-C7 cobb's angle (CA) and C2-C7 sagittal vertical axis (SVA) means were −2.85±10.68 and 1.51± 0.79, respectively. Facet tropism was found in 98% of the sample in at least one level on either axial or sagittal plane. Axial C 2–3 CFT and sagittal C4-5 were correlated with CA (r=0.246, P 0.043, r= −278, P 0.022), respectively. In addition, C2-C7 sagittal vertical axis (SVA) was moderately correlated with axial c2-3 FT (r= −0.330, P 0.006) Also, several significant correlations were detected in our model Cervical vertebral slopes and CFT at the related level. Nonetheless, high BMI was associated with multi-level and multiplane CFT with higher odd's ratios at the lower levels. This study shows that CFT at higher levels is correlated with increasing CA and decreasing SVA and at lower levels with decreasing CA. Obesity is a risk factor for CFT

Acetabular morphology and orientation differs from ethnic group to another. Thus, investigating the natural history of the parameters that are used to assess both was a matter of essence. Nevertheless, clarification the picture of normal value in our society was the main aim of this study. However, Acetabular head index (AHI) and center edge angle (CEA) were the most sensitive indicative parameters for acetabular dysplasia. Hence, they were the main variables used in evaluation of acetabular development. A cross-sectional retrospective study that had been done in a tertiary center. Computed tomography abdomen scouts’ radiographs of non-orthopedics patients were included. They had no history of pelvic or hips’ related symptoms or fractures in femur or pelvis. Images’ reports were reviewed to exclude those with tumors in the femur or pelvic bones. A total of 81 patients was included with 51% of them were males. The mean of age was 10.38± 3.96. CEA was measured using Wiberg technique, means of CEA were 33.71±6.53 and 36.50±7.39 for males and females, respectively. Nonetheless, AHI means were 83.81±6.10 and 84.66±4.17 for males and females, respectively. On the other hand, CEA was increasing by a factor 0.26 for each year (3-18, range). In addition, positive significant correlation was detected between CEA and age as found by linear regression r 2 0.460 (f(df1,79) =21.232, P ≤0.0001). Also, Body mass index (BMI) was positively correlated with CEA r 0.410, P 0.004). This study shows that obesity and aging are linked to increased CEA. Each ethnic group has its own normal values that must be studied to avoid premature diagnosis

Infections in spine surgery are relatively common and devastating complications, a significant burden to the patient and the healthcare system. Usually, the treatment of SSIs consists of aggressive and prolonged antibiotic therapy, multiple debridements, and in chronic cases, hardware removal. Infections are correlated with worse subjective outcomes and even higher mortality. Depending on the type of spine surgery, the infection rate has been reported to be as higher as 20%. Recently silver-coated implants have been introduced in spine surgery to reduce the incidence of post-operative infections and to improve implant survivorship. The aim of the present study is to evaluate complications and outcomes in patients treated with silver-coated implants because of spine infection. All consecutive patients who had spine stabilization with a silver-coated implant from 2018 to 2021 were screened for inclusion in the study. Inclusion criteria were: (1) six months of minimum follow-up; (2) previous surgical site infection; hematogenous spondylodiscitis requiring surgical stabilization. Demographic and surgical information were obtained via chart review, all the device-related complications and the reoperation rate were also reported. A total of 57 patients were included in the present study. The mean age was 63.4 years, and there were 36 (63%) males and 21 (37%) females. Among the included cases, 57% were SSIs, 33% were spondylodiscitis, and 9% were hardware mobilization. Comorbidities such as diabetes mellitus, obesity, smoke, and oncological history were significant risk factors. In addition, the organisms cultured were Staphylococcus species in most of the cases. At six months of follow-up, 40% of patients were considered free from infection, while 20% needed multiple surgeries. The present research showed satisfactory results of silver-coated implants for the treatment of spine infection