The October 2024 Arthroplasty Roundup³⁶⁰ looks at: Breaking the mould: female representation in arthroplasty surgery remains low, with elbow leading the way; Post COVID-19: where are we with the 'catch up' in England and Wales?; Prevalence and clinical impact of sarcopenia in patients undergoing total joint replacement: a systematic review and a meta-analysis; Total joint replacement and sleep: the state of the evidence.

Aims. This study aimed to determine the expression and clinical significance of a cartilage protein, cartilage oligomeric matrix protein (COMP), in knee osteoarthritis (OA) patients. Methods. A total of 270 knee OA patients and 93 healthy controls were recruited. COMP messenger RNA (mRNA) and protein levels in serum, synovial fluid, synovial tissue, and fibroblast-like synoviocytes (FLSs) of knee OA patients were determined using enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and immunohistochemistry. Results. COMP protein levels were significantly elevated in serum and synovial fluid of knee OA patients, especially those in the advanced stages of the disease. Serum COMP was significantly correlated with radiological severity as well as measures of body composition, physical performance, knee pain, and disability. Receiver operating characteristic curve analysis unveiled a diagnostic value of serum COMP as a biomarker of knee OA (41.64 ng/ml, area under the curve (AUC) = 1.00), with a sensitivity of 99.6% and a specificity of 100.0%. Further analysis uncovered that COMP mRNA expression was markedly upregulated in the inflamed synovium of knee OA, consistent with immunohistochemical staining revealing localization of COMP protein in the lining and sub-lining layers of knee OA inflamed synovium. Most notably, relative COMP mRNA expression in knee OA synovium was positively associated with its protein levels in serum and synovial fluid of knee OA patients. In human knee OA FLSs activated with tumour necrosis factor-alpha, COMP mRNA expression was considerably up-regulated in a time-dependent manner. Conclusion. All results indicate that COMP might serve as a supportive diagnostic marker for knee OA in conjunction with the standard diagnostic methods. Cite this article: Bone Joint Res 2024;13(6):261–271

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

We hypothesised that diet-induced obesity (DIO) would result in inferior enthesis healing in a rat model of rotator cuff (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 culled, 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 before surgery and subsequently reversed in the HF-CD group after surgery. Histologically, the appearance of the repaired entheses was poorer in both the HFD and HF-CD groups compared with the CD group at 12 weeks after surgery, with semiquantitative scores of 6.2 (P<0.01), 4.98 (P<0.01), and 8.7 of 15, respectively. The repaired entheses in the HF-CD group had a significantly lower load to failure (P=0.03) at 12 weeks after surgery compared with the CD group, while the load to failure in the HFD group was low but not significantly different (P=0.10). Plasma leptin were negatively correlated with histology scores and load to failure at 12 weeks after 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. Circulating levels of leptin significantly correlated with poor healing outcomes. This pre-clinical rodent model demonstrates that obesity is a potentially modifiable factor that impairs RC healing and increases the risk of failure after RC surgery

Aims

Sarcopenia is characterized by a generalized progressive loss of skeletal muscle mass, strength, and physical performance. This systematic review primarily evaluated the effects of sarcopenia on postoperative functional recovery and mortality in patients undergoing orthopaedic surgery, and secondarily assessed the methods used to diagnose and define sarcopenia in the orthopaedic literature.

Aims

The effect of the gut microbiota (GM) and its metabolite on bone health is termed the gut-bone axis. Multiple studies have elucidated the mechanisms but findings vary greatly. A systematic review was performed to analyze current animal models and explore the effect of GM on bone.

Background

Although there are predictive equations that estimate the total fat mass obtained from multiple-site ultrasound (US) measurements, the predictive equation of total fat mass has not been investigated solely from abdominal subcutaneous fat thickness. Therefore, the aims of this study were; (1) to develop regression-based prediction equations based on abdominal subcutaneous fat thickness for predicting fat mass in young- and middle-aged adults, and (2) to investigate the validity of these equations to be developed.

Aims

Previous research has demonstrated increased early complication rates following total hip arthroplasty (THA) in obese patients, as defined by body mass index (BMI). Subcutaneous fat depth (FD) has been shown to be an independent risk factor for wound infection in cervical and lumbar spine surgery, as well as after abdominal laparotomy. The aim of this study was to investigate whether increased peritrochanteric FD was associated with an increased risk of complications in the first year following THA.

Aims. To examine the relationship of sex steroid hormones with osteopenia in a nationally representative sample of men in the USA. Methods. Data on bone mineral density (BMD), serum sex hormones, dairy consumption, smoking status, and body composition were available for 806 adult male participants of the cross-sectional National Health and Nutrition Examination Survey (NHANES, 1999-2004). We estimated associations between quartiles of total and estimated free oestradiol (E2) and testosterone (T) and osteopenia (defined as 1 to 2.5 SD below the mean BMD for healthy 20- to 29-year-old men) by applying sampling weights and using multivariate-adjusted logistic regression. We then estimated the association between serum hormone concentrations and osteopenia by percentage of body fat, frequency of dairy intake, cigarette smoking status, age, and race/ethnicity. Results. Men in the lowest quartile of total E2 concentrations (< 21.52 pg/ml) had greater odds of osteopenia compared with men in the highest quartile (odds ratio (OR) 2.29, 95% confidence interval (CI) 1.11 to 4.73; p-trend = 0.030). Total and free T were not associated with osteopenia. Low total E2 concentrations were associated with greater odds of osteopenia among non-daily dairy consumers (p-trend = 0.046), current or former smokers (p-trend = 0.032), and younger men (p-trend = 0.031). No differences were observed by race/ethnicity and obesity. Conclusion. In this nationally representative study of the USA, men with lower total E2 were more likely to have osteopenia, which was particularly evident among younger men, men with less-than-daily dairy consumption, and current or former smokers. Cite this article:Bone Joint Res. 2020;9(3):139–145

Objectives. Insufficient protein ingestion may affect muscle and bone mass, increasing the risk of osteoporotic fractures in the elderly, and especially in postmenopausal women. We evaluated how a low-protein diet affects bone parameters under gonadal hormone deficiency and the improvement led by hormone replacement therapy (HRT) with 17β-oestradiol. Methods. Female Wistar rats were divided into control (C), ovariectomized (OVX), and 17β-oestradiol-treated ovariectomized (OVX-HRT) groups, which were fed a control or an isocaloric low-protein diet (LP; 6.6% protein; seven animals per group). Morphometric, serum, and body composition parameters were assessed, as well as bone parameters, mechanical resistance, and mineralogy. Results. The results showed that protein restriction negatively affected body chemical composition and bone metabolism by the sex hormone deficiency condition in the OVX group. The association between undernutrition and hormone deficiency led to bone and muscle mass loss and increased the fragility of the bone (as well as decreasing relative femoral weight, bone mineral density, femoral elasticity, peak stress, and stress at offset yield). Although protein restriction induced more severe adverse effects compared with the controls, the combination with HRT showed an improvement in minimizing these damaging effects, as it was seen that HRT had some efficacy in maintaining muscle and bone mass, preserving the bone resistance and minimizing some deleterious processes during the menopause. Conclusion. Protein restriction has adverse effects on metabolism, leading to more severe menopausal symptoms, and HRT could minimize these effects. Therefore, special attention should be given to a balanced diet during menopause and HRT. Cite this article: Bone Joint Res 2019;8:573–581

Aims

To date, no study has demonstrated an improvement in postoperative outcomes following elective joint arthroplasty with a focus on nutritional intervention for patients with preoperative hypoalbuminaemia. In this prospective study, we evaluated differences in the hospital length of stay (LOS), rate of re-admission, and total patient charges for a malnourished patient study population who received a specific nutrition protocol before surgery.

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

Thigh-calf contact force is the force acting on posterior side of the thigh and calf during deep knee flexion. It has been reported the force is important to analyze the kinetics of a lower limb and a knee joint. Some previous researches reported the measured thigh-calf contact force, however, the values varied among the reports. Furthermore, the reports indicated that there were large variations even in a single report. One of the reports tried to find the relationship between the magnitude of thigh-calf contact force and anthropometric measurement as height, weight or perimeter of the lower limb, however, there could not found clear correlations. We considered that the cause of the variations might be the difference of the posture. At heel-rise squatting posture, we can bend or stand upright the upper body. Therefore we tried to create the equation to estimate the thigh-calf contact force by multiple regression analysis, using the anthropometric and posture parameters as explanatory variables. We performed the experiment to measure thigh-calf contact force, joint angles and anthropometric information. Test subjects were 10 healthy male. First we measured their height, weight, perimeter of the thigh and muscle mass of the legs and whole body. Muscle mass was measured by body composition meter (BC-118E, Tanita Co., Japan). Then, test subjects were asked to squat with their heels lifted and with putting the pressure distribution sensor between thigh and calf. And they bent their upper body forward and backward. The pressure sensor to be used was ConfroMat System (Nitta Co., Japan). After that, we measured the joint angles of the hip, knee and ankle, and the angle between the floor and upper body using the videos taken during the experiment. Then, we created the equation to estimate the thigh-calf contact force by linear combination of the anthropometric values and joint angles. The coefficients were settled as to minimize the average error between measured and estimated values. Results are shown in Fig.1. Forces were normalized by the body weight of the test subjects. Because the horizontal axes show the measured and vertical axis show the estimated values, the estimation is accurate when the plots are near the 45-degree line. Average error was 0.11BW by using only physical values, 0.15BW by angles and 0.06BW using both values. And the maximum error was 0.69BW, 0.43BW and 0.32BW respectively. Thus we could estimate the thigh-calf contact force by multiple regressions, using both physical parameters and angles to indicate the posture. Using the equation, we would be able to analyze the kinetics of a lower limb by physical and motion measurement. Our future work might be increasing the number of subjects to consider the appropriateness, because the test subjects of this study were very limited

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