Cigarette smoking has a negative impact on the skeletal system by reducing bone mass and increasing the risk of fractures through its direct or indirect effects on bone remodeling. Recent evidence shows that smoking causes an imbalance in bone turnover, making bone vulnerable to osteoporosis and fragility fractures. In addition, cigarette smoking is known to have deleterious effects on fracture healing, as a positive correlation has been shown between the daily number of cigarettes smoked and years of exposure to smoking, although the underlying mechanisms are not fully understood. Smoking is also known to cause several medical and surgical complications responsible for longer hospital stays and a consequent increase in resource consumption. Smoking cessation is, therefore, highly advisable to prevent the onset of metabolic bone disease. However, some of the consequences appear to continue for decades. Based on this evidence, the aim of our work was to assess the impact of smoking on the skeletal system, particularly bone fractures, and to identify the pathophysiological mechanisms responsible for the impairment of fracture healing. Because smoking represents a major public health problem, understanding the association between cigarette smoking and the occurrence of bone disease is necessary in order to identify potential new targets for intervention

Abstract. OBJECTIVES. Bone health deterioration is a major public health issue. General guidelines for the limitation of bone loss prescribe a healthy lifestyle and a minimum level of physical activity. However, there is no specific recommendation regarding targeted activities that can effectively maintain lumbar spine bone health. To provide a better understanding of such influencing activities, a new predictive modelling framework was developed to study bone remodelling under various loading conditions. METHODS. The approach is based on a full-body subject-specific musculoskeletal model [1] combined with structural finite element models of the lumbar vertebrae. Using activities recorded with the subject, musculoskeletal simulations provide physiological loading conditions to the finite element models which simulate bone remodelling using a strain-driven optimisation algorithm [2]. With a combination of daily living activities representative of a healthy lifestyle including locomotion activities (walking, stair ascent and descent, sitting down and standing up) and spine-focused activities involving twisting and reaching, this modelling framework generates a healthy bone architecture in the lumbar vertebrae. The influence of spine-focused tasks was studied by adapting healthy vertebrae to an altered loading scenario where only locomotion activities were performed. RESULTS. The spine-focused activities were responsible for 57% of the overall bone mechanical stimulus of the five lumbar vertebrae. Cortical bone maintenance was more influenced by these activities in the superior vertebrae than in the inferior ones, with a stimulus degradation of 74% in L1 against 24% in L5 when adapted to the altered loading scenario. Trabecular bone stimulus degradation varied between 53% and 68%. CONCLUSION. The study suggests that locomotion activities are insufficient to maintain lumbar spine bone health. When appropriate, larger spine movements should be recommended as part of the minimum daily physical activities. 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

Femoral neck fractures account for half of all hip fractures and are recognized as a major public health problem associated with a high socioeconomic burden. Whilst internal fixation is preferred over arthroplasty for physiologically younger patients, no consensus exists about the optimal fixation device yet. The recently introduced implant Femoral Neck System (FNS) (DePuy Synthes, Zuchwil, Switzerland) was developed for dynamic fixation of femoral neck fractures and provides angular stability in combination with a minimally invasive surgical technique. Alternatively, the Hansson Pin System (HPS) (Swemac, Linköping, Sweden) exploits the advantages of internal buttressing. However, the obligate peripheral placement of the pins, adjacent to either the inferior or posterior cortex, renders the instrumentation more challenging. The aim of this study was to evaluate the biomechanical performance of FNS versus HPS in a Pauwels II femoral neck fracture model with simulated posterior comminution. Forty-degree Pauwels II femoral neck fractures AO 31-B2.1 with 15° posterior wedge were simulated in fourteen paired fresh-frozen human cadaveric femora, followed by instrumentation with either FNS or HPS in pair-matched fashion. Implant positioning was quantified by measuring the shortest distances between implant and inferior cortex (DI) as well as posterior cortex (DP) on anteroposterior and axial X-rays, respectively. Biomechanical testing was performed in 20° adduction and 10° flexion of the specimens in a novel setup with simulated iliopsoas muscle tension. Progressively increasing cyclic loading was applied until construct failure. Interfragmentary femoral head-to-shaft movements, namely varus deformation, dorsal tilting and rotation around the neck axis were measured by means of motion tracking and compared between the two implants. In addition, varus deformation and dorsal tilting were correlated with DI and DP. Cycles to 5/10° varus deformation were significantly higher for FNS (22490±5729/23007±5496) versus HPS (16351±4469/17289±4686), P=0.043. Cycles to 5/10° femoral head dorsal tilting (FNS: 10968±3052/12765±3425; HPS: 12244±5895/13357±6104) and cycles to 5/10° rotation around the femoral neck axis (FNS: 15727±7737/24453±5073; HPS: 15682±10414/20185±11065) were comparable between the implants, P≥0.314. For HPS, the outcomes for varus deformation and dorsal tilting correlated significantly with DI and DP, respectively (P=0.025), whereas these correlations were not significant for FNS (P≥0.148). From a biomechanical perspective, by providing superior resistance against varus deformation and performing in a less sensitive way to variations in implant placement, the angular stable Femoral Neck System can be considered as a valid alternative to the Hansson Pin System for the treatment of Pauwels II femoral neck fractures

Background and purpose. Over the past decade, it has become apparent that more often than not musculoskeletal pain occurs in more than one site in an individual, and traditional approaches, where pain has been studied as a narrow site-specific problem, are often not feasible. The overall aim of this study is to describe clusters of pain using a large population-based sample. This presentation will focus specifically on musculoskeletal co-complaints in back pain sufferers. Methods and results. The Danish National Institute of Public Health has since 1987 conducted national representative health interview surveys of the adult Danish population some of which have included questions on musculoskeletal complaints. We used latent class analysis to identify latent classes of musculoskeletal complaints that occurred alongside a primary complaint of back pain. In addition, probabilities that specific sites occurred as co-complaints were determined. Three latent classes were identified and they exhibited quite different patterns of musculoskeletal co-complaints. The most commonly occurring class had a low probability of any co-complaints, the second most commonly occurring class had a high probability of pain in the neck, shoulders and mid-back, while the least commonly occurring class had very high probabilities of pain at all other body sites. Conclusions. Latent class analysis can be used to identify distinctly different groups of pain patterns in persons primarily complaining of back pain. The three groups identified likely have very different prognoses. Conflicts of Interest. None. Source of Funding. None. This abstract has not been previously published in whole or substantial part nor has it been presented previously at a national meeting

Introduction. Low back pain is a major public health problem in our society. Degeneration of intervertebral disc (IVD) appears to be the leading cause of chronic low-back pain [1]. Mechanical stimulations including compressive and tensional forces are directly implicated in IVD degeneration. Several studies have implicated the cytoskeleton in mechanotransduction [2, 3], which is important for communication and transport between the cells and extracellular matrix (ECM). However, the potential roles of the cytoskeletal elements in the mechanotransduction pathways in IVD are largely unknown. Methods. Outer annulus fibrosus (OAF) and nucleus pulposus (NP) cells from skeletally mature bovine IVD were either seeded onto Flexcell¯ type I collagen coated plates or seeded in 3% agarose gels, respectively. OAF cells were subjected to cyclic tensile strain (10%, 1Hz) and NP cells to cyclic compressive strain (10%, 1Hz) for 60 minutes. Post-loading, cells were processed for immunofluorescence microscopy and RNA extracted for quantitative PCR analysis. Results. F-actin reorganisation was evident in OAF and NP cells subjected to tensile and compressive strain respectively and is likely due to load-induced differential mRNA expression of actin-binding proteins. The vimentin network was also more intricately organised in loaded NP cells. Compressive strain increased type II collagen and aggrecan transcription in NP cells, whereas levels decreased in OAF cells under tension. mRNA levels of ECM-degrading enzymes were significantly reduced in both cell populations after loading. Conclusion. Tensile and compressive strains induce different mechano-responses in the organisation/expression of cytoskeletal elements and on markers of IVD metabolism. Differential mechano-regulation of anabolic and catabolic ECM components in the OAF and NP populations reflects their respective mechanical environments in situ

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.

Osteoporosis is a systemic skeletal disorder characterized by reduced bone mass and deterioration of bone microarchitecture, which results in increased bone fragility and fracture risk. Casein kinase 2-interacting protein-1 (CKIP-1) is a protein that plays an important role in regulation of bone formation. The effect of CKIP-1 on bone formation is mainly mediated through negative regulation of the bone morphogenetic protein pathway. In addition, CKIP-1 has an important role in the progression of osteoporosis. This review provides a summary of the recent studies on the role of CKIP-1 in osteoporosis development and treatment.

Cite this article: X. Peng, X. Wu, J. Zhang, G. Zhang, G. Li, X. Pan. The role of CKIP-1 in osteoporosis development and treatment. Bone Joint Res 2018;7:173–178. DOI: 10.1302/2046-3758.72.BJR-2017-0172.R1.

Objectives

This study reports on a secondary exploratory analysis of the early clinical outcomes of a randomised clinical trial comparing robotic arm-assisted unicompartmental knee arthroplasty (UKA) for medial compartment osteoarthritis of the knee with manual UKA performed using traditional surgical jigs. This follows reporting of the primary outcomes of implant accuracy and gait analysis that showed significant advantages in the robotic arm-assisted group.

Objectives

This study looked to analyse the expression levels of microRNA-140-3p and microRNA-140-5p in synovial fluid, and their correlations to the severity of disease regarding knee osteoarthritis (OA).

Objectives

Temperature is known to influence muscle physiology, with the velocity of shortening, relaxation and propagation all increasing with temperature. Scant data are available, however, regarding thermal influences on energy required to induce muscle damage.

Reported rates of dislocation in hip hemiarthroplasty (HA) for the treatment of intra-capsular fractures of the hip, range between 1% and 10%. HA is frequently performed through a direct lateral surgical approach. The aim of this study is to determine the contribution of the anterior capsule to the stability of a cemented HA through a direct lateral approach.

A total of five whole-body cadavers were thawed at room temperature, providing ten hip joints for investigation. A Thompson HA was cemented in place via a direct lateral approach. The cadavers were then positioned supine, both knee joints were disarticulated and a digital torque wrench was attached to the femur using a circular frame with three half pins. The wrench applied an external rotation force with the hip in extension to allow the hip to dislocate anteriorly. Each hip was dislocated twice; once with a capsular repair and once without repairing the capsule. Stratified sampling ensured the order in which this was performed was alternated for the paired hips on each cadaver.

Comparing peak torque force in hips with the capsule repaired and peak torque force in hips without repair of the capsule, revealed a significant difference between the ‘capsule repaired’ (mean 22.96 Nm, standard deviation (sd) 4.61) and the ‘capsule not repaired’ group (mean 5.6 Nm, sd 2.81) (p < 0.001). Capsular repair may help reduce the risk of hip dislocation following HA.

Cite this article: Bone Joint J 2015;97-B:141–4.

Objectives

To assess the sensitivity and specificity of self-reported osteoporosis compared with dual energy X-ray absorptiometry (DXA) defined osteoporosis, and to describe medication use among participants with the condition.