Irregularity in Plantar Fascia, Muscle Edema and Tendon Thickness in Patients with High-Risk for Diabetic Foot

Aim To investigate the alterations in the plantar fascia (PF), intrinsic muscles, and tendons in the feet of patients at high risk for developing diabetic foot. Methods The healthy feet of 22 patients with type 2 diabetes, who had developed diabetic foot ulcers on a single foot without any pathology on the contralateral extremity, and those of 22 healthy volunteers were evaluated by magnetic resonance imaging. The volume of the Achilles tendon (AT), the surface area of the PF, the thickness of AT, flexor hallucis longus, flexor digitorum longus, tibialis posterior, and peroneus longus tendons, irregularity in the PF, and edema of intrinsic foot muscles were examined. Results Nineteen patients (86%) had irregularity in the PF, whereas none of the healthy controls had any (p<0.001). Intrinsic muscle edema was more common in the group with diabetes (p=0.006). The volume of AT and the surface area of PF were decreased in patients with peripheral arterial disease (PAD) (p<0.05). Patients with diabetes mellitus but without PAD had a larger surface area of PF than that of controls (p<0.05). There were no differences in the volume of AT, the surface area of the PF, and other tendon thickness between the groups. Conclusion Irregularity in the PF and muscle edema may indicate a high risk for the diabetic foot. The presence of PAD may lead to regression in the structure of AT and PF.

Screening power of STIR muscle MRI in Critical illness myo-neuropathy and GBS in the ICU

Introduction; Critical illness myo-neuropathy [CIMN] or ICU acquired weakness [CIMN] is a common cause of weakness in ICU patients. It is diagnosed by clinical features, nerve conduction studies and muscle/nerve biopsies. Methods; The MRI muscle STIR images of 7 patients with suspected CIMN and 7 GBS patients were reviewed. Results; All 7 patients with CIMN showed diffuse muscle edema, predominating in the lower limbs. Only one patient with GBS showed abnormal MRI changes (14%) and MRI was normal in 86%. The sensitivity of MRI to detect CIMN was 100%, whereas the specificity was 85.7%. Thus, the positive predictive value of MRI in this situation was 87.5% and the negative predictive value was 100%. Conclusions; Muscle STIR imaging may help to differentiate between CIMN and GBS and can modify the diagnostic algorithm of CIMN.

MRI and muscle enzymes do not support the diagnosis of local anesthetic myotoxicity: a descriptive case series

BackgroundThe presence of thigh muscle edema as characterized by increased signal intensity on MRI has been used to support the diagnosis of presumed local anesthetic-induced myotoxicity reported after total knee arthroplasty (TKA) with continuous adductor canal block (CACB). However, neither postoperative baseline imaging appearance nor muscle enzyme values have been described in conjunction with this clinical scenario. Thus, the usefulness of MRI or enzymatic biomarkers of muscle injury for supporting the diagnosis of local anesthetic myotoxicity is unknown.MethodsThis descriptive case series documents postoperative MRI appearance of the ipsilateral upper leg, plus preoperative and postoperative creatine phosphokinase and aldolase values in volunteer patients who underwent uncomplicated TKA with CACB.ResultsIn 27 volunteer patients with no postsurgical evidence of clinically relevant myotoxicity, anterior thigh muscle edema was universally evident on imaging (n=12) and muscle enzyme values (n=19) were normal or only slightly elevated.ConclusionsThe non-specificity of these findings suggests that MRI and near normal muscle enzyme levels are of limited diagnostic value when there is clinical suspicion of local anesthetic myotoxicity in the setting of TKA with CACB.Trial registration numberNCT04821245.

Radiological Spectrum of Active Sacroiliitis by Conventional Radiography and MRI

Introduction: The aim of the present study was to compare the role of Conventional Radiography and Magnetic Resonance Imaging (MRI), in diagnosis of active sacroiliitis and differentiation between inflammatory and infective sacroiliitis.Methods: Fifty two cases of active sacroiliitis diagnosed on MRI from August 2017 to August 2019 were included in study. All the patients were subjected to conventional radiology, MRI and findings were co-related with clinical and laboratory findings. Conventional radiography was used to evaluate structural changes. MR images were evaluated for bone lesions (extent and distribution of bone marrow edema and presence of bone erosions), soft-tissue lesions (capsulitis, extra capsular fluid collections, and peri-articular muscle edema) and joint space reduction for differentiation between infective and inflammatory etiology.Results: Conventional radiography showed sclerosis, erosion, partial and complete ankylosis. Thick capsulitis, extra capsular fluid collection, and peri-articular muscle edema were all more frequently observed in infective sacroiliitis (p<0.001). Iliac-dominant bone marrow edema more common in spondyloarthritis (p<0.001). When periarticular muscle edema was the sole predictor, unilateral sacroiliitis in spondyloarthritis was correctly identified in 79.16% of cases, and infectious sacroiliitis was correctly identified in 82.14% of cases.Conclusions: MRI is the optimum imaging modality to diagnose active sacroiliitis. MRI plays an essential role in better demonstrating early alterations and inflammatory activity and aid in differentiation of infective and inflammatory sacroiliitis. Conventional radiography with low sensitivity can be used as a screening tool and follow-up of patients with sacroiliitis.

Getting it Right the First Time: Frozen Sections for Diagnosing Necrotizing Soft Tissue Infections

Background The aim of this study was to investigate which histopathologic findings are most indicative for necrotizing soft tissue infections (NSTIs) in ambivalent cases. Methods Patients undergoing surgical exploration for suspected NSTIs with obtainment of incisional biopsies for histopathological assessment were included from January 2013 until August 2019. The frozen sections and formalin-fixed paraffin-embedded (FFPE) samples were retrospectively re-assessed. The primary outcome was the discharge diagnosis. Results Twenty-seven (69%) biopsies of the 39 included samples were from patients with NSTIs. Microscopic bullae (p = 0.043), severe fascial inflammation (p < 0.001) and fascial necrosis (p < 0.001) were significantly more often present in the NSTI group compared to the non-NSTI group. Muscle edema (n = 5), severe muscle inflammation (n = 5), muscle necrosis (n = 8), thrombosis (n = 10) and vasculitis (n = 5) were most frequently only seen in the NSTI group. In thirteen tissues samples, there were some discrepancies between the severity of findings in the frozen section and the FFPE samples. None of these discrepancies resulted in a different diagnosis or treatment strategy. Conclusion Microscopic bullae, severe fascial or muscle inflammation, fascial or muscle necrosis, muscle edema, thrombosis and vasculitis upon histopathological evaluation all indicate a high probability of a NSTI. At our institution, diagnosing NSTIs is aided by using intra-operative frozen section as part of triple diagnostics in ambivalent cases. Based on the relation between histopathologic findings and final presence of NSTI, we recommend frozen section for diagnosing NSTIs in ambivalent cases.

Diagnostic Value of Muscle Ultrasound for Myopathies and Myositis

Purpose of Review The purpose of this review is to critically discuss the use of ultrasound in the evaluation of muscle disorders with a particular focus on the emerging use in inflammatory myopathies. Recent Findings In myopathies, pathologic muscle shows an increase in echogenicity. Muscle echogenicity can be assessed visually, semi-quantitatively, or quantitatively using grayscale analysis. The involvement of specific muscle groups and the pattern of increase in echogenicity can further point to specific diseases. In pediatric neuromuscular disorders, the value of muscle ultrasound for screening and diagnosis is well-established. It has also been found to be a responsive measure of disease change in muscular dystrophies. In chronic forms of myositis like inclusion body myositis, ultrasound is very suitable for detecting markedly increased echogenicity and atrophy in affected muscles. Acute cases of muscle edema show only a mild increase in echogenicity, which can also reverse with successful treatment. Summary Muscle ultrasound is an important imaging modality that is highly adaptable to study various muscle conditions. Although its diagnostic value for neuromuscular disorders is high, the evidence in myositis has only begun to accrue in earnest. Further systematic studies are needed, especially in its role for detecting muscle edema.

Homoplasmic mitochondrial tRNAPro mutation causing exercise-induced muscle swelling and fatigue

ObjectiveTo demonstrate the causal role in disease of the MT-TP m.15992A>T mutation observed in patients from 5 independent families.MethodsLactate measurement, muscle histology, and mitochondrial activities in patients; PCR-based analyses of the size, amount, and sequence of muscle mitochondrial DNA (mtDNA) and proportion of the mutation; respiration, mitochondrial activities, proteins, translation, transfer RNA (tRNA) levels, and base modification state in skin fibroblasts and cybrids; and reactive oxygen species production, proliferation in the absence of glucose, and plasma membrane potential in cybrids.ResultsAll patients presented with severe exercise intolerance and hyperlactatemia. They were associated with prominent exercise-induced muscle swelling, conspicuous in masseter muscles (2 families), and/or with congenital cataract (2 families). MRI confirmed exercise-induced muscle edema. Muscle disclosed severe combined respiratory defect. Muscle mtDNA had normal size and amount. Its sequence was almost identical in all patients, defining the haplotype as J1c10, and sharing 31 variants, only 1 of which, MT-TP m.15992A>T, was likely pathogenic. The mutation was homoplasmic in all tissues and family members. Fibroblasts and cybrids with homoplasmic mutation had defective respiration, low complex III activity, and decreased tRNAPro amount. Their respiratory complexes amount and tRNAPro aminoacylation appeared normal. Low proliferation in the absence of glucose demonstrated the relevance of the defects on cybrid biology while abnormal loss of cell volume when faced to plasma membrane depolarization provided a link to the muscle edema observed in patients.ConclusionsThe homoplasmic MT-TP m.15992A>T mutation in the J1c10 haplotype causes exercise-induced muscle swelling and fatigue.

Experience in the use of magnetic resonance imaging in the diagnosis of professional myofibrosis

The analysis showed that the absolute prognostic criterion for the initial stage of the disease is muscle edema and the optimal impulse sequence for its visualization - diffuse-weighted image and a post-contrast T1-weighted image for revealing the disturbance of the histo-hematic barrier penetration.