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《The spine journal》2022,22(4):660-676
BACKGROUND CONTEXTPrevious studies have proposed that there is a relationship between low back pain (LBP) and morphology and composition of paraspinal muscles. However, results have been conflicting, especially regarding fatty infiltration of muscles.PURPOSEThe primary goal of this study was to review and analyze results from imaging studies which investigated morphological and composition changes in the multifidus, erector spinae and psoas major muscles in people with LBP.STUDY DESIGN/SETTINGSystematic review with meta-analysis.PATIENT SAMPLEA patient sample was not requiredOUTCOME MEASURESThis review did not have outcome measures.METHODSPubMed, Scopus, Web of Sciences, EMBASE and ProQuest were searched for eligible studies up to 31st July 2020 (all languages). A systematic search of electronic databases was conducted to identify studies investigating the association between the morphology and fat content of lumbar muscles in people with LBP compared with a (no LBP) control group. 13,795 articles were identified. Based on the screening for inclusion/ exclusion, 25 were included. The quality of the studies was evaluated using the Newcastle-Ottawa Scale. From the 25 articles, 20 were included in the meta-analysis.RESULTSResults showed that the total cross-sectional area of the multifidus was smaller in people with LBP (Standardized mean difference, SMD = -0.24, 95% CI = -0.5 to 0.03). Combined SMDs showed a medium effect of LBP on increasing multifidus muscle fat infiltration (SMD = 0.61, 95% CI = 0.30 to 0.91). There were no LBP related differences identified in the morphology or composition of the lumbar erector spine and psoas major muscles.CONCLUSIONSPeople with LBP were found to have somewhat smaller multifidus muscles with a significant amount of intramuscular fat infiltration. Varying sample size, age and BMI of participants, quality of studies and the procedures used to measure fat infiltration are possible reasons for inconsistencies in results of previous studies.  相似文献   
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IntroductionReverse shoulder arthroplasty (RSA) alters normal anatomic relationships and results in increased deltoid forces. Which alter physiologic stress patterns in the acromion resulting in fractures. The purpose of this study was to evaluate the effect of acromion anatomy on the stress levels and risk of acromial fracture after RSA.MethodsA lateralization onlay design of the Exactech Equinoxe RSA standard stem was used for all four different acromial sizes (ranging from −5.0 mm to +5.0 mm) and compared to standard normal shoulder model (acromial size 0). A finite element analysis (FEA) model was then constructed for each case and quasi-static analysis was carried out to determine the highest minimum principal stress (HMPS) for each case and this was used to predict fatigue life percentage (FLP) of the acromion.ResultsFor smaller acromion sizes of −5 mm and -2.5 mm, the HMPS was found to be 1.87 and 1.24 times higher than the standard, respectively. The HMPS for the +2.5 mm acromial size was 0.95 times compared to the standard and 1.04 times higher for the +5 mm acromial size. According to our model, the highest FLP was seen when the acromion size was +2.5 mm (case 4 - 178%) and the lowest FLP was seen when it was -5 mm (−0.06%).ConclusionOur results suggest that there is an optimal acromion size (+2.5 mm from normal male) that leads to the lowest fracture risk in RSA. Surgeons must be aware of acromion size as a critical factor in deltoid tensioning, acromial stress, and risk of acromial fracture when selecting optimal implant designs and sizes for RSA.Level of evidence: Basic Science Study  相似文献   
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Abstract

Supporting patients in making informed healthcare decisions is a cornerstone of ethical medical practice. Surgeons frequently draw for and show images to patients when consenting them for operations but the value of this practice in informed decision-making is unclear. An audit was conducted in a General Surgery Department. 244 patients completed questionnaires on the value of visual materials when giving consent for surgery. The complexity of the operations was classified into “simple”, “moderate” or “complex”. 100% of patients felt they had given informed consent to surgery. 62% of patients received at least one form of visual material during the consenting process. All patients who received a drawing, and 99% of those provided with other images, valued these resources. Visual materials were considered more useful to patients when giving consent for moderate or complex operations than simple ones. Approximately one third of patients who did not receive visual materials would have appreciated these when making an informed decision. This research highlights the value of surgeons drawing for, and providing other visual resources to, their patients as part of the consent process. There is a role for further research and training materials in drawing skills for surgeons.  相似文献   
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BackgroundsPreoperative widespread pain sensitization or pain catastrophizing could be associated with chronic pain after total knee arthroplasty (TKA). The aim of the present study was to examine the association between postoperative pain in patients undergoing TKA and preoperative factors, including patient characteristics and preoperative central sensitization as well as pain catastrophizing.MethodsPreoperative TKA patients were evaluated using the Central Sensitization Inventory (CSI)-9 and Pain Catastrophizing Scale (PCS). Postoperative knee pain was evaluated using a numerical rating scale (NRS) 6 months after TKA. Statistical analyses were performed to assess the relationship between NRS 6 months after TKA and preoperative factors, including patient characteristics, CSI-9, and PCS.ResultsWe enrolled 58 consecutive patients with osteoarthritis who underwent TKA. Using cutoff of 14, postoperative NRS was higher in the patients with ≥14 than the patients with <14 in CSI (p = 0.025). Postoperative NRS was higher in the patients with ≥30 than the patients with <30 in PCS (p = 0.043). Preoperative PCS was a significant risk factor of postoperative pain using a multivariate analysis.ConclusionsSurgeon should recognize preoperative PCS could affect postoperative pain 6 months after TKA.  相似文献   
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《Arthroscopy》2022,38(2):323-324
The surgical management of elbow contracture remains a challenging proposition, and both open and arthroscopic approaches have been described with varying degrees of success. In particular, previous series involving severe cases have left much to be desired in terms of clinical outcomes and complication rates. Herein lies an opportunity for innovation via alternative, arthroscopic approaches. In the hands of a single senior surgeon, arthroscopic elbow contracture release can be accomplished, even in the setting of severe, post-traumatic cases, with an expectation for substantial improvements in the arc of motion and comparable, if not better, complication rates than reported previously in other series. However, concerns regarding the reproducibility of these results persist and should compel future efforts to prove that these techniques can yield similar results among a group of surgeons.  相似文献   
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