Interdepartmental Spread of Innovations: A Multicentre Study of the Enhanced Recovery After Surgery Programme

World Journal of Surgery - Spread of evidence-based innovations beyond pioneering settings is essential to improve quality of care. This study aimed to evaluate the influence of a national project...     

Knee Implant Loosening Detection: A Vibration Analysis Investigation

Knee implant loosening is mainly caused by the weakness of the prosthesis-bone interface and is the main reason for surgical revisions. However, pre-operative diagnosis is difficult due to lack of accurate tests. In this study, we developed a vibration-based system to detect the loosening of the tibial implant of an instrumented knee prosthesis. The proposed system includes an instrumented vibrator for transcutaneous stimulation of the bone in a repeatable manner, and accelerometer sensors integrated into the implants to measure the propagated vibration. A coherence-based detection technique was proposed to distinguish the loosened implants from the secure ones. Fourteen ex vivo lower limbs were used, on which the knee prosthesis was implanted, and harmonic-forced vibration was applied on the tibia. The input–output coherence measure provided 92.26% accuracy, a high sensitivity (91.67%) and specificity (92.86%). This technique was benchmarked against power spectrum based analysis of the propagated vibration to the implant. In particular, loosening detection based on new peak appearance, peak shift, and peak flattening in power spectra showed inferior performance to the proposed coherence-based technique. As such, application of vibration on our instrumented knee prosthesis together with input–output coherence analysis enabled us to distinguish the secure from loose implants.     

How chromosomal deletions can unmask recessive mutations? Deletions in 10q11.2 associated with CHAT or SLC18A3 mutations lead to congenital myasthenic syndrome

A congenital myasthenia was suspected in two unrelated children with very similar phenotypes including several episodes of severe dyspnea. Both children had a 10q11.2 deletion revealed by Single Nucleotide Polymorphisms array or by Next Generation Sequencing analysis. The deletion was inherited from the healthy mother in the first case. These deletions unmasked a recessive mutation at the same locus in both cases, but in two different genes: CHAT and SLC18A3.     

Biochemical MRI Predicts Hip Osteoarthritis in an Experimental Ovine Femoroacetabular Impingement Model

BackgroundCam-type femoroacetabular impingement (FAI) resulting from an abnormal nonspherical femoral head shape leads to chondrolabral damage and is considered a cause of early osteoarthritis. A previously developed experimental ovine FAI model induces a cam-type impingement that results in localized chondrolabral damage, replicating the patterns found in the human hip. Biochemical MRI modalities such as T2 and T2* may allow for evaluation of the cartilage biochemistry long before cartilage loss occurs and, for that reason, may be a worthwhile avenue of inquiry.Questions/purposesWe asked: (1) Does the histological grading of degenerated cartilage correlate with T2 or T2* values in this ovine FAI model? (2) How accurately can zones of degenerated cartilage be predicted with T2 or T2* MRI in this model?MethodsA cam-type FAI was induced in eight Swiss alpine sheep by performing a closing wedge intertrochanteric varus osteotomy. After ambulation of 10 to 14 weeks, the sheep were euthanized and a 3-T MRI of the hip was performed. T2 and T2* values were measured at six locations on the acetabulum and compared with the histological damage pattern using the Mankin score. This is an established histological scoring system to quantify cartilage degeneration. Both T2 and T2* values are determined by cartilage water content and its collagen fiber network. Of those, the T2* mapping is a more modern sequence with technical advantages (eg, shorter acquisition time). Correlation of the Mankin score and the T2 and T2* values, respectively, was evaluated using the Spearman’s rank correlation coefficient. We used a hierarchical cluster analysis to calculate the positive and negative predictive values of T2 and T2* to predict advanced cartilage degeneration (Mankin ≥ 3).ResultsWe found a negative correlation between the Mankin score and both the T2 (p < 0.001, r = −0.79) and T2* values (p < 0.001, r = −0.90). For the T2 MRI technique, we found a positive predictive value of 100% (95% confidence interval [CI], 79%–100%) and a negative predictive value of 84% (95% CI, 67%–95%). For the T2* technique, we found a positive predictive value of 100% (95% CI, 79%–100%) and a negative predictive value of 94% (95% CI, 79%–99%).ConclusionsT2 and T2* MRI modalities can reliably detect early cartilage degeneration in the experimental ovine FAI model.

Clinical Relevance

T2 and T2* MRI modalities have the potential to allow for monitoring the natural course of osteoarthrosis noninvasively and to evaluate the results of surgical treatments targeted to joint preservation.     

COVID-19-related severe MS exacerbation with life-threatening Takotsubo cardiomyopathy in a previously stable patient and interference of MS therapy with long-term immunity against SARS-CoV-2

Journal of Neurology -     

A web‐based survey to identify current practice in skeletal pin site management

Infections associated with percutaneous pins and wires are common complications which can have a significant impact on patient outcomes. A survey was undertaken to identify current practice and gain insight into variations of clinical practice. Invitations were sent by email to complete an electronic questionnaire using SurveyMonkey. The survey was left open for 100 days. The single largest group of respondents (37.4%, n = 120) cleansed pin sites daily, with significant differences identified between medical and nursing professions (P = 0.02), and country of practice (P < 0.001). Significant differences were also identified in the use of different cleansing solutions between medical and nursing professions (P < 0.001) and country (P < 0.001). The majority group preferences were saline 30% (n = 96) and alcoholic chlorhexidine 29.6% (n = 95). Pin site crusts were routinely removed by 57.9% (n = 186). Pin sites were left exposed by 50.3% (n = 160). Dry gauze was identified as the most common dressing used to dress pin sites, however, substantial variation was identified in the types of dressings used. Compression was not routinely applied to pin sites by 51.6% (n = 165). There remains considerable diversity of practice when caring for pin sites. Further research is required to identify the most effective methods in preventing pin site infection.