The transition from enthesis physiological responses in health to aberrant responses that underpin spondyloarthritis mechanisms.

PURPOSE OF REVIEW: Despite immunology and translational therapeutics advances in inflammatory arthritis over the past two decades, the enthesis, which is the epicentric of the spondyloarthritis family pathological process, retains many mysteries because of tissue inaccessibility that hampers direct immune study. As entheses are subject to almost continuous mechanical stress and spondyloarthritis is linked to microdamage or injury and joint stress, it is cardinal to understand the physiological changes occurring within the entheses not only to be able to differentiate disease from health but also to understand the transition normal physiology break down and its merges into spondyloarthritis-related disease. RECENT FINDINGS: Imaging has played a major role in understanding the enthesis in human. Remarkable insights from enthesis functioning and microdamage in normal and with ageing including those linked to body mass index is emerging. The impact of mechanical stress and degenerative conditions on the development of the secondary entheseal vascular changes is not understood. Of note, ultrasound studies in psoriasis have shown higher power Doppler changes compared to controls pointing towards a role for vascular changes in the development of enthesitis in psoriatic arthritis. SUMMARY: The literature pertaining to normal entheses changes with age, microdamage and vascular changes in health is providing a roadmap for understanding of the enthesis and its potential role in evolution of spondyloarthritis including psoriatic arthritis.

Modeling of iterative time-reversed ultrasonically encoded optical focusing in a reflection mode.

Time-reversed ultrasonically-encoded (TRUE) optical focusing is a promising technique to realize deep-tissue optical focusing by employing ultrasonic guide stars. However, the sizes of the ultrasound-induced optical focus are determined by the wavelengths of the ultrasound, which are typically tens of microns. To satisfy the need for high-resolution imaging and manipulation, iterative TRUE (iTRUE) was proposed to break this limit by triggering repeated interactions between light and ultrasound and compressing the optical focus. However, even for the best result reported to date, the resolutions along the ultrasound axial and lateral direction were merely improved by only 2-fold to 3-fold. This observation leads to doubt whether iTRUE can be effective in reducing the size of the optical focus. In this work, we address this issue by developing a physical model to investigate iTRUE in a reflection mode numerically. Our numerical results show that, under the influence of shot noises, iTRUE can reduce the optical focus to a single speckle within a finite number of iterations. This model also allows numerical investigations of iTRUE in detail. Quantitatively, based on the parameters set, we show that the optical focus can be reduced to a size of 1.6 µm and a peak-to-background ratio over 104 can be realized. It is also shown that iTRUE cannot significantly advance the focusing depth. We anticipate that this work can serve as useful guidance for optimizing iTRUE system for future biomedical applications, including deep-tissue optical imaging, laser surgery, and optogenetics.

Ultrasonographic tissue perfusion analysis at implant and palatal donor sites following soft tissue augmentation: A clinical pilot study.

AIM: To describe the application of power Doppler Ultrasonography (US) for evaluating blood flow at implant and palatal donor sites following soft tissue augmentation with the connective tissue graft (CTG). MATERIALS AND METHODS: Five patients exhibiting a peri-implant soft tissue dehiscence received treatment with a coronally advanced flap and corresponding CTG. Power Doppler US was used for assessing blood volume at baseline, 1 week, 1 month, 6 months and 12 months post-surgery for assessing blood-flow dynamics at the implant and palatal donor sites. The speed-weighted and power-weighted colour pixel density (CPPD) were computed from colour velocity (CV) and colour power (CP), respectively. RESULTS: A mean increase in CV of 199.25% was observed at the midfacial region of the implant sites after 1 week compared to baseline. CV and CP were increased in all sites at 1 week and 1 month. At 6 and 12 months, the mean CV appeared lower than baseline at the implant sites. CCPD was increased at the palatal donor sites and at the great palatine foramen areas at the 1-week and 1-month post-operative evaluations. CONCLUSIONS: Power Doppler US is a non-invasive and valuable tool for estimating tissue perfusion and CPPD variation during different phases of intra-oral soft tissue graft healing.

Quantitative Assessment of the Apparent Diffusion Coefficient Values of the Inflammatory Connective Tissue Around the Mandibular Condyle in Rheumatoid Arthritis.

PURPOSE: Magnetic resonance imaging can detect soft- and hard-tissue abnormalities and has become the primary imaging modality for temporomandibular joints. However, few studies have quantitatively evaluated rheumatoid arthritis (RA) in temporomandibular joints using diffusion-weighted imaging. The purpose of this study was to assess the apparent diffusion coefficient (ADC) values of the inflammatory connective tissue around the mandibular condyle in RA. METHODS: This was a retrospective cohort study. We analyzed the magnetic resonance imaging studies of patients with suspected temporomandibular joint disorders performed between April 2008 and August 2020. The predictor variable was disease status (RA-y/n). The primary outcome variable was the mean of ADC values of the connective tissue around the mandibular condyle. The other variables were age and sex. Furthermore, the ADC values were compared between the 2 groups. Data were analyzed using a Mann-Whitney U test, Spearman's correlation coefficient, and a receiver operating characteristic curve. P < .05 was considered to indicate statistical significance. RESULTS: In total, 35 patients (18 normal patients and 17 patients with RA) were included. The mean ADC values were 1.26 ± 0.11 × 10-3 mm2/s and 1.60 ± 0.19 × 10-3 mm2/s in the control and RA groups, respectively (P < .001). Receiver operating characteristic analysis revealed that a cutoff of 1.37 for ADC values for RA provided an accuracy of 0.86. The sensitivity and specificity of ADC values were 0.94 and 0.83, respectively. CONCLUSIONS: ADC values of the inflammatory connective tissue around the mandibular condyle in RA were significantly higher in the RA group than those in the control group. This parameter might be useful for the quantitative evaluation of RA.

Randomized controlled clinical trial comparing implant sites augmented with a volume-stable collagen matrix or an autogenous connective tissue graft: 3-year data after insertion of reconstructions.

AIM: To assess mid-term clinical, radiographic and profilometric outcomes at implant sites, previously grafted with a volume-stable collagen matrix (VCMX) or an autogenous subepithelial connective tissue graft (SCTG). METHODS: VCMX or SCTG were randomly applied to single implant sites in 20 patients. Following abutment connection and insertion of final reconstructions (baseline), patients were re-examined at 6 months (6M), at 1 year (FU-1) and at 3 years (FU-3). Measurements included the following: clinical data, radiographic measurement of first bone to implant contact (fBIC), soft tissue thickness and volumetric outcomes. Non-parametric tests and estimates were applied for the statistical analysis. RESULTS: The median buccal mucosal thickness increased by 0.5 mm (Q1: -0.5; Q3: 1.25) (VCMX) (p = .281) and by 0.8 mm (Q1: 0.0; Q3: 2.5) (SCTG) (p = .047) between BL and FU-3 (intergroup p = .303). The profilometric changes of the buccal soft tissues demonstrated a median decrease between BL and FU-3 of -0.2 mm (Q1: -0.5; Q3: -0.1) (p = .039) for VCMX and a decrease of -0.1 mm (Q1: -0.8; Q3: 0.1) (p = .020) for SCTG, respectively (intergroup p = .596). Peri-implant soft tissues and bone levels remained healthy throughout the entire study period. PROMs did not show any significant differences between the groups nor significant changes over time. CONCLUSION: Minimal changes of the peri-implant tissue contour as well as of the soft tissue thickness were observed at implant sites previously grafted with VCMX or SCTG.

A novel, fully digital approach to quantifying volume gain after soft tissue graft surgery. A pilot study.

OBJECTIVE: Measuring soft tissue thickness after mucogingival surgery has traditionally been performed by means of a calibrated transgingival probe. The main aim of this study was to apply a non-invasive technique based on digital images formatted as Standard Tessellation Language (STL) files to quantify soft tissue volume after connective tissue grafting. CLINICAL INNOVATION REPORT: Ten patients who presented Cairo Class I gingival recession were selected for connective tissue grafting using the tunnel technique. In all patients, the initial position of the gingiva and quantity of keratinized tissue were recorded, and gingival recession was scanned with an intra-oral scanner. Six months after surgery, the same intra-oral parameters were recorded and compared with the initial registers using digital volumetric analysis software. RESULTS: Complete root coverage was obtained in most patients (90%), mean coverage being of 2.70 mm with a mean increase in volume of 115.49 mm3 in the treated areas. No pattern was identified that indicated a statistically significant relation between gingival recession and coverage volume in mm3 . CONCLUSIONS: Digital processing of pre- and post-treatment images makes it possible to measure the volume of tissue gained after tissue graft surgery simply and non-invasively. The technique is an objective and reproducible method for measuring soft tissue thickness.

Hard and soft tissue alterations during the healing stage of immediate implant placement and provisionalization with or without connective tissue graft: A randomized clinical trial.

AIMS: To evaluate the hard and soft tissue alterations of immediately placed and provisionalized implants with or without connective tissue graft (CTG). MATERIALS AND METHODS: Single unsalvageable maxillary incisors were replaced with immediately placed and provisionalized implants in 42 participants. The patients were randomly assigned to receive simultaneous CTG (test group) and not receive CTG (control group). Digital impression and cone-beam computed tomography images were obtained before extraction and after 6 months. Mid-facial gingival margin migrations, soft tissue contour changes and hard tissue remodelling were analysed and compared between the two groups using three-dimensional superimposition method. RESULTS: Forty participants completed the study. The test group showed significantly less buccal tissue collapse in the area 2-5 mm apical to the gingival margin. In both groups, the mid-facial gingival margin migrated in an apico-palatal direction and the socket void, except for a triangular space in the bucco-coronal region, demonstrated radiographic new bone formation without statistically significant differences. CONCLUSIONS: The CTG used with immediate implant placement and provisionalization could compensate for the facial tissue collapse, but it did not benefit maintenance of the mid-facial gingival margin position during the 6-month follow-up. New bone formation observed radiographically can be expected in most areas of the socket void, regardless of CTG use (ChiCTR-1900028494).

Utilization of MR imaging in myodural bridge complex with relevant muscles: current status and future perspectives.

The aim of this study is to review and discuss the literature on the utilization of magnetic resonance imaging (MRI) in investigating the structure and feasible function of the myodural bridge complex (MDBC) with relevant muscles, which will be useful to understand the function of the MDB. The myodural bridge (MDB) is a soft tissue connective bridge that provides a fascial continuity between the musculature/ligament and cervical spinal dura mater (SDM) in the suboccipital areas. All of these involved structures are referred to as the MDBC. It would transfer tensile forces effectively from involved suboccipital muscles/ligament to SDM during head movement. Despite present achievements, its anatomic and functional role is still unclear. MRI enables not only in vivo visualization of ligaments, musculature and spinal dura with conventional T1W, T2W and PDW imaging, but also functional evaluation of MDBC with relevant muscles, such as muscles' fatty infiltration, cross-sectional area changes and injuries. Though some functional MRI techniques have not been used for the MDBC with relevant muscles now, these techniques have great potential to better understand function of MDBC including its suspected clinical role. MRI is likely the most powerful tool to study MDBC and relevant muscles with only limited exploration so far.

Efficacy of Peak Hounsfield Units of the Visceral Fat Area in Predicting Postoperative Complications after Pancreaticoduodenectomy.

BACKGROUND: Morbidity following pancreaticoduodenectomy (PD) has been reported to remain high. This study sought to measure the peak Hounsfield units (HUs) of visceral attenuation in patients undergoing PD and to assess the quality of adipocytes by comparing these measurements with perioperative factors. METHODS: Patients undergoing PD were retrospectively identified (n = 108). Abdominal perimeter, subcutaneous fat area (SFA), visceral fat area (VFA), and peak HU of the VFA were measured. Logistic regression analysis was used to identify independent predictors of postoperative pancreatic fistula (POPF) or complications. Histopathological examination was performed for qualitative diagnosis of the stromal tissue. RESULTS: The overall rate of POPF was 16%, and severe complications occurred in 23% of the cases. A criterion for peak HU of the VFA only independently predicted POPF (p = 0.007) in the multivariate analysis. A criterion for peak HU of the VFA (p = 0.015) was associated with an increased rate of postoperative severe complications in the univariate analysis. The peak HU of the VFA was significantly correlated with abdominal perimeter (p < 0.001) and VFA (p < 0.001). The peak HU of the VFA was significantly correlated with adipocyte diameter (p < 0.001) and the ratio of stromal connective tissue area around the adipocytes (p < 0.001). CONCLUSION: The peak HU of the VFA was an independent factor contributing to severe complications, including POPF after PD. It reflects the amount of stromal connective tissue around the adipocytes.

Clinical and imaging features in fibro-adipose vascular anomaly (FAVA).

BACKGROUND: Fibro-adipose vascular anomaly (FAVA) is a rare and recently described complex vascular malformation. The clinical and imaging features and morphology can be confusing and often overlap with features of other vascular malformations and tumors. OBJECTIVE: To present the imaging characterization of FAVA in association with clinical features. MATERIALS AND METHODS: We retrospectively evaluated clinical and imaging (MRI, sonography and venography) findings in FAVA. We documented the clinical presentation, lesion morphology, imaging characteristics, tissue distribution, pattern of contrast enhancement and vascular characteristics. RESULTS: Thirty-eight people (31 female, 7 male) ages 1-30 years (mean 12 years) were diagnosed with FAVA based on clinical findings combined with imaging or histopathological findings (n=17). Most lesions were in the lower extremity (n=36). Three patterns were noticed: focal, focal infiltrative and diffuse. CONCLUSION: Fibro-adipose vascular anomaly, a rare and complex vascular malformation, has distinct clinical and imaging features that a radiologist should be familiar with to avoid delay in diagnosis and to direct appropriate management.

Serum Biomarkers for Connective Tissue and Basement Membrane Remodeling are Associated with Vertebral Endplate Bone Marrow Lesions as Seen on MRI (Modic Changes).

Vertebral endplate bone marrow lesions, visualized on magnetic resonance imaging (MRI) as Modic changes (MC), are associated with chronic low back pain (cLBP). Since guidelines recommend against routine spinal MRI for cLBP in primary care, MC may be underdiagnosed. Serum biomarkers for MC would allow early diagnosis, inform clinical care decisions, and supplement treatment monitoring. We aimed to discover biomarkers in the blood serum that correlate with MC pathophysiological processes. For this single-site cross-sectional study, we recruited 54 subjects with 38 cLBP patients and 16 volunteers without a history of LBP. All subjects completed an Oswestry Disability Index (ODI) questionnaire and 10-cm Visual Analog Score (VAS) for LBP (VASback) and leg pain. Lumbar T1-weighted and fat-saturated T2-weighted MRI were acquired at 3T and used for MC classification in each endplate. Blood serum was collected on the day of MRI. Biomarkers related to disc resorption and bone marrow fibrosis were analyzed with enzyme-linked immune-absorbent assays. The concentration of biomarkers between no MC and any type of MC (AnyMC), MC1, and MC2 were compared. The Area Under the Curve (AUC) of the Receiver Operating Characteristics were calculated for each biomarker and for bivariable biomarker models. We found that biomarkers related to type III and type IV collagen degradation and formation tended to correlate with the presence of MC (p = 0.060-0.088). The bivariable model with the highest AUC was PRO-C3 + C4M and had a moderate diagnostic value for AnyMC in cLBP patients (AUC = 0.73, specificity = 78.9%, sensitivity = 73.7%). In conclusion, serum biomarkers related to the formation and degradation of type III and type IV collagen, which are key molecules in bone marrow fibrosis, correlated with MC presence. Bone marrow fibrosis may be an important pathophysiological process in MC that should be targeted in larger biomarker and treatment studies.

The myodural bridge complex defined as a new functional structure.

PURPOSE: The connective tissue between suboccipital muscles and the cervical spinal dura mater (SDM) is known as the myodural bridge (MDB). However, the adjacent relationship of the different connective tissue fibers that form the MDB remains unclear. This information will be highly useful in exploring the function of the MDB. METHODS: The adjacent relationship of different connective tissue fibers of MDB was demonstrated based upon three-dimensional visualization model, P45 plastinated slices and histological sections of human MDB. RESULTS: We found that the MDB originating from the rectus capitis posterior minor muscle (RCPmi), rectus capitis posterior major muscle (RCPma) and obliquus capitis inferior muscle (OCI) in the suboccipital region coexists. Part of the MDB fibers originate from the ventral aspect of the RCPmi and, together with that from the cranial segment of the RCPma, pass through the posterior atlanto-occipital interspace (PAOiS) and enter into the posterior aspect of the upper cervical SDM. Also, part of the MDB fibers originate from the dorsal aspect of the RCPmi, the ventral aspect of the caudal segment of the RCPma, and the ventral aspect of the medial segment of the OCI, enter the central part of the posterior atlanto-axial interspace (PAAiS) and fuse with the vertebral dura ligament (VDL), which connects with the cervical SDM. CONCLUSIONS: Our findings prove that the MDB exists as a complex structure which we termed the 'myodural bridge complex' (MDBC). In the process of head movement, tensile forces could be transferred possibly and effectively by means of the MDBC. The concept of MDBC will be beneficial in the overall exploration of the function of the MDB.

Collagen networks determine viscoelastic properties of connective tissues yet do not hinder diffusion of the aqueous solvent.

Collagen accounts for the major extracellular matrix (ECM) component in many tissues and provides mechanical support for cells. Magnetic Resonance (MR) Imaging, MR based diffusion measurements and MR Elastography (MRE) are considered sensitive to the microstructure of tissues including collagen networks of the ECM. However, little is known whether water diffusion interacts with viscoelastic properties of tissues. This study combines highfield MR based diffusion measurements, novel compact tabletop MRE and confocal microscopy in collagen networks of different cross-linking states (untreated collagen gels versus additional treatment with glutaraldehyde). The consistency of bulk rheology and MRE within a wide dynamic range is demonstrated in heparin gels, a viscoelastic standard for MRE. Additional crosslinking of collagen led to an 8-fold increased storage modulus, a 4-fold increased loss modulus and a significantly decreased power law exponent, describing multi-relaxational behavior, corresponding to a pronounced transition from viscous-soft to elastic-rigid properties. Collagen network changes were not detectable by MR based diffusion measurements and microscopy which are sensitive to the micrometer scale. The MRE-measured shear modulus is sensitive to collagen fiber interactions which take place on the intrafiber level such as fiber stiffness. The insensitivity of MR based diffusion measurements to collagen hydrogels of different cross-linking states alludes that congeneric collagen structures in connective tissues do not hinder extracellular diffusive water transport. Furthermore, the glutaraldehyde induced rigorous changes in viscoelastic properties indicate that intrafibrillar dissipation is the dominant mode of viscous dissipation in collagen-dominated connective tissue.

A new and simplified comprehensive ultrasound protocol of haemophilic joints: the Universal Simplified Ultrasound (US-US) protocol.

AIM: To present a new protocol to optimise ultrasound (US) assessment of haemophilic arthropathy. MATERIALS AND METHODS: Ultrasound of haemophilic arthropathy joints was performed using three different ultrasound protocols, namely, the Toronto-Vellore Comprehensive Ultrasound (TVC-US) protocol, the Haemophilia Early Arthropathy Detection with Ultrasound (HEAD-US), and the newly developed Universal Simplified Ultrasound (US-US) protocol. Synovial hypertrophy, haemosiderin deposition, effusion, erosion, and cartilage loss were evaluated in 20 joints. The reliability and diagnostic efficiency of these protocols was compared using magnetic resonance imaging (MRI). RESULTS: The correlation between the TVC-US and US-US protocols for synovial hypertrophy was excellent: kappa significance (KS) was 1, but was substantial (KS=0.65) with the HEAD-US protocol. For effusion, both the TVC-US and the HEAD-US protocols had substantial correlation with the US-US protocol (KS=0.7 and 0.6 respectively). The correlation for erosion and cartilage loss was excellent between the TVC-US and the US-US with MRI (KS=1), but poor (KS=0) with the HEAD-US protocol. The US-US protocol also had good interobserver agreement (KS=1). CONCLUSION: The accuracy of the US-US protocol is comparable to the TVC-US protocol and MRI and is superior to the HEAD-US protocol in the assessment of haemophilic arthropathy.

Ultrasound Features of Ankle Retinacula: Normal Appearance and Pathologic Findings.

Disorders of retinacula are frequent in acute and repetitive microtrauma of the ankle. Ultrasound (US), thanks to its spatial resolution and dynamic capabilities, is routinely used in the evaluation of the posttraumatic ankle for accurate delineation of ligaments and tendons. In addition, US can provide a depiction of normal retinacula and a detailed assessment of their pathologic changes. An accurate US assessment of ankle retinacula is helpful in choosing the proper treatment. In this pictorial essay, we briefly review the normal anatomy of ankle retinacula, describe their normal US appearance, and present a wide range of US pathologic abnormalities.

Radiographic Soft Tissue Thickness Differentiating Pyogenic Flexor Tenosynovitis From Other Finger Infections.

PURPOSE: Characteristic swelling has been described as a differentiating sign of pyogenic flexor tenosynovitis (PFT) but has not been validated. We conducted a retrospective study of adults with finger infections to compare radiographic parameters of soft tissue dimensions. Our hypothesis was that in patients with digit infections, radiographic soft tissue thickness measurement would differ between PFT and non-PFT infected digits. METHODS: Patients with a finger infection and radiographic evaluation were identified retrospectively at a large academic medical center and divided into 2 groups: PFT (n = 31) and non-PFT infections (n = 31). We defined PFT as purulence in the tendon sheath or positive culture growth from the sheath at surgery. Non-PFT infections included all other finger infections such as abscesses and cellulitis. A total of 15 radiographic measurements were made on all included digits. Ratios and differences were calculated to characterize the pattern of swelling for each infected finger. Bivariate analysis was performed to identify potential predictor variables between the PFT and non-PFT groups. Logistic regression was performed to reduce confounding and model potential relationships. RESULTS: Neither presence of diffuse swelling nor the shape of finger swelling distinguished PFT from non-PFT infections. All finger infections resulted in diffuse swelling. Pyogenic flexor tenosynovitis was distinguished by differential volar soft tissue thickness minus dorsal soft tissue thickness on radiographs at the proximal phalanx level (9 ± 1 mm for PFT vs 5 ± 1 mm for non-PFT). This was an independent predictor of PFT. The area under the receiver operating curve was 0.83 (95% confidence interval, 0.73-0.94). A difference between volar and dorsal soft tissue swelling of 7 mm or greater had a positive predictive value of 82% with a sensitivity of 84% and specificity of 74%. A difference of 10 mm predicted PFT infection with 76% probability (95% confidence interval, 73% to 99%). CONCLUSIONS: Pyogenic flexor tenosynovitis may result in uniform finger swelling, but this does not appear to distinguish PFT from other finger infections. Acute PFT swelling is distinguished by differential volar versus dorsal radiographic soft tissue thickness at the level of the proximal phalanx. The term "fusiform swelling" is a misnomer for the appearance of acute PFT because the finger is not spindle-shaped. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic IV.

Observation and determination of periodontal tissue profile using optical coherence tomography.

BACKGROUND AND OBJECTIVE: Diagnosis is a crucial step in periodontal treatment. The aim of this study was to evaluate the effectiveness of optical coherence tomography (OCT) for observation and determination of periodontal tissue profiles in vivo. MATERIAL AND METHODS: In experiment 1, refractive indices of purified water, porcine gingiva and human gingiva at 1330 nm were determined for the analysis of OCT images of periodontal tissues. In experiment 2, OCT examination was performed in the midlabial apico-coronal plane of mandibular anteriors in 30 Asian volunteers with healthy gingiva. Sulcus depth was measured on intra-oral photographs taken during probing. In the OCT images, the gingival, epithelial and connective tissue thickness, and the position of alveolar bone crest were determined and finally, the biologic width was measured. RESULTS: Refractive indices of purified water, porcine gingiva and human gingiva were 1.335, 1.393 and 1.397, respectively. Cross-sectional images of gingival epithelium, connective tissue and alveolar bone were depicted in real-time. The sulcular and junctional epithelium could be visualized occasionally. Laser penetration and reflection were limited to a certain depth with an approximate maximal imaging depth capability of 1.5 mm and OCT images of the periodontal structure were not clear in some cases. The average maximal thickness of gingiva and epithelium and biologic width at the mandibular anteriors were 1.06 ± 0.21, 0.49 ± 0.15 and 2.09 ± 0.60 mm, respectively. CONCLUSION: OCT has promise for non-invasive observation of the periodontal tissue profile in detail and measurement of internal periodontal structures including biologic width in the anterior region.

Evaluation of tissue changes following intramuscular infiltration of lidocaine in rainbow trout Oncorhynchus mykiss.

Rainbow trout Oncorhynchus mykiss were infiltrated with either saline or lidocaine adjacent to the dorsal fin to assess histopathological changes. Infiltration was done as if it were being used as a local anaesthetic. Tissue lesions and associated tissue healing were examined over a period of 30 days. Most changes occurred at the cranial site of where the solution was first infiltrated. The infiltration of a dose of 10 mg kg-1 of lidocaine appears to have damaged the skeletal muscle and connective tissues more than a similar volume of saline, especially during the first 15 days. The primary changes included haemorrhage, inflammation and muscle degeneration and necrosis. By day 30 post-infiltration inflammatory lesions were either nearly or completely absent, signs of myofibre regeneration were noted in only one fish. This experiment shows local anaesthetics and saline can produce localized tissue damage, especially during the first 2 weeks post infiltration. Care should be taken to allow the fish to heal for at least 30 days and probably more, no matter the solution administered, especially if giving repeated injections or infiltrations at the same site.

Characterization of the tissue crossing the supratrochlear aperture of the humerus using histochemical techniques.

INTRODUCTION: The supratrochlear aperture (STA) is the opening observed in the septum that separates the olecranon from the coronoid fossae. Numerous studies have shown that there is considerable variation in the occurrence of this feature within and among populations. MATERIALS AND METHODS: Cadavers (n = 43) were assessed for the presence of the STA by means of X-ray. Ten samples of STA-bearing bones and an equal number of controls without STA were obtained from cadavers using a hole saw. These samples were decalcified, fixed in formalin and processed for histological assessment in differing (ascending) grades of alcohol before being embedded in paraffin wax. Sections (10 µm thick) were stained with haematoxylin and eosin (H&E) for general architecture as well as the rapid one-step Mallory-Heidenhain stain for bone and connective tissue. RESULTS: The STA samples exhibited an abundance of connective tissue arranged in regular bundles of fibers across the STA. In contrast, the controls showed only bone tissue in the septum. DISCUSSION AND CONCLUSION: The arrangement of connective tissue fibers organized in regular bundles is a characteristic of strength, which may indicate that the STA is under sustained stress or pressure from the olecranon and coronoid processes of the ulna. It remains debatable whether the STA should continue to be considered as a foramen in life as we demonstrate that it is obliterated by connective tissue. It contains no neurovascular structures, making it unlike other structures defined as foramina.

Comparison of Pedal Soft Tissue Thickness Between Those With and Without Diabetes.

Ulceration is a serious consequence of diabetes that can lead to disability in patients with diabetes. One of the risk factors for ulceration is high foot pressure. The thickness of the pedal soft tissue is important because it has a cushioning effect. Soft tissue atrophy causes elevation in the plantar pressure, which, in turn, causes ischemia. Therefore, we investigated the severity of pedal soft tissue atrophy caused by diabetes and aging. From February 2009 to February 2016, we examined the feet of 261 patients treated in our hospital using magnetic resonance imaging. We divided the patients enrolled in the study into 2 groups. The first group included 52 patients with diabetes but without peripheral arterial disease and the second group included 47 patients without diabetes. We measured the vertical distances under all patients' metatarsal heads using T1-weighted magnetic resonance imaging and measured the pedal soft tissue thickness using the PACS workstation (m-view). We compared the soft tissue thicknesses of the 2 groups and performed statistical analyses of the relationships between these data and other parameters using 2-way analysis of variance. The soft tissue under the first to fourth metatarsal heads was thinner in the diabetic patients than in the nondiabetic patients (first metatarsal, 6.4 versus 8.69; second metatarsal, 8.85 versus 10.64; third metatarsal, 8.15 versus 9.21; fourth metatarsal, 7.38 versus 8.54; p < .05). Aging had no effect on pedal soft tissue atrophy in either group. In conclusion, our study confirmed that diabetic patients experience more severe plantar soft tissue atrophy than nondiabetic patients. We have developed a standard procedure to enable the prediction of pedal soft tissue atrophy severity in diabetic patients.