Neck Deformity Research Articles

Spiral Oblique Retinacular Ligament Procedure Using Flexor Digitorum Profundus Hemi-Tendon Transfer: Anatomical Basis and Clinical Application

The spiral oblique retinacular ligament (SORL) procedure acts as a dynamic tenodesis to restore distal interphalangeal joint (DIP) extension and restrain proximal interphalangeal hyperextension. Despite the ingenious technique based on the oblique retinacular ligament anatomy, obtaining strong internal fixation remains an issue during the SORL procedure. We present a modified technique using the flexor digitorum profundus (FDP) hemi-tendon transfer. We dissected 5 fresh cadaveric specimens to evaluate morphometric parameters of the SORL procedure using the hemi-FDP. The volar groove of the FDP tendon was identified in zone I of the flexor sheath and the tendon was divided into radial and ulnar bundles. The selected hemi-tendon was divided at the proximal edge of the A1 pulley and a SORL procedure was performed through a transosseous tunnel in the distal phalanx. This technique was used in 3 patients with swan neck deformity. The optimal distance between the DIP joint and the anterior drill hole of the transosseous tunnel was 7.6 mm (range, 6.8-8.5 mm). The relative loss of length of the tendon owing to the SORL path was 25.8 mm (range, 19.6-29.9 mm). In the clinical cases, the procedure improved DIP joint extension lag and prevented proximal interphalangeal joint hyperextension. Preserving one-half of the FDP allowed complete flexion of the DIP joint. The procedure is technically feasible. Its main advantages are that a distal suture is not required and that the substantial length of the tendon allows sturdy proximal internal fixation. Therapeutic V.

Features of free skin grafting to correct post-burn neck deformities in children

BACKGROUND: In the literature, various methods of reconstructive plastic surgery for neck cicatricial contractures, from free skin grafting to expander dermotension and microsurgical tissue complex autotransplantation, are widely covered. However, very little attention has been paid to conservative measures aimed at stabilizing surgical treatment results.
 AIM: This study aims to evaluate the long-term results of free skin grafting of neck granulating wounds after burns and secondary relapsing scar contracture correction. The study also aims to analyze the causes of poor results and demonstrate the possibility of using free skin grafting to correct neck contractures with basic preventive measures.
 MATERIALS AND METHODS: Forty-six patients with neck burn cicatricial sequelae were treated at the clinic of trauma sequelae in H. Turner National Medical Research Center from 2017 to 2019. The patients were divided into two groups: group 1 patients with neck contractures after plasty of granulating wounds with free skin autografts, and group 2 patients with a relapse of neck contracture after corrective reconstructive surgery.
 Anamnestic data analysis enabled establishing the actual volume of preventive rehabilitation measures in both patient groups. The classification by N.E. Povstyany (1973) was used to determine the severity of contracture.
 RESULTS: The most severe neck contractures, grade III and IV, developed in group 1 patients (grade III 41.2%). In group 2 patients, there was a limitation of neck extension, corresponding to grades I (33.3%) and II (58.3%).
 Conservative preventive measures as immobilization and compression therapy were absent in group 1 in 100% of cases. The most common preventive measure was the prescription of topical anti-scar drugs.
 Two-stage skin grafting with full-thickness skin autografts combined with conservative measures made it possible to correct neck contractures of grade I-IV completely and obtain good aesthetic results.
 CONCLUSION: The main reason for neck contractures development is the retraction of skin autografts, which inevitably develops in the absence of appropriate preventive measures.
 Correction of neck contractures using free skin grafting combined with preventive immobilization using a Schantz collar and a compression half-mask allows obtaining good functional and aesthetic results.

The Protective Effect of Chicoric Acid on the Mancozeb-induced Male Reproductive Damage in Mice:

Background and Aim: This study aimed to evaluate the protective effect of chicoric acid (CA) on mancozeb-induced male reproductive damage in mice. Methods: 65 NMRI male mice were randomly divided into 7 groups (n=8); 1: control group, 2: MZB–induced toxicity 3: MZB+ atropine (0.25 mg/kg daily), groups 4, 5, and 6: MZB+25, 50 and 100 mg/kg of CA respectively. 7: CA (100 mg). The mice were sacrificed thirty-five days later and blood and testis samples were obtained. Testosterone levels, sperm parameters, protamine deficiency, and sperm chromatin dispersion (SCD) were used to evaluate the reproductive system function. Results: The sperm count and sperm viability decreased in the MZB-intoxicated group; the sperm DNA fragmentation and protamine deficiency increased in this group. Head and neck deformity decreased in MZB+ CA groups (p<0.05). In MZB+ CA groups, the sperm motility type A, and B increased than the MZB group, abnormal sperm morphology within 100 mg/kg CA groups was less than 50 and 25 mg/kg. The groups pretreated with CA showed a significant increase in Leydig cells. Conclusion: The results revealed that chicoric acid has a protective effect on testis tissue damage induced by MZB. So, this is a promising therapeutic choice for the treatment of male infertility. *Corresponding Author: Hakimeh Akbari; Email: akbarih@gerums.ac.ir Please cite this article as: Forouzandeh H, Ahmadi I, Akbari H. The Protective Effect of Chicoric Acid on the Mancozeb-induced Male Reproductive Damage in Mice. Arch Med Lab Sci. 2021;7:1-10 (e6). https://doi.org/10.22037/amls.v7.33149

Effect of macrophages in semen on sperm quality

BackgroundThis was a cross-sectional study in China which analyzed the levels of macrophages (Mφ) in semen and evaluated the influence of Mφ levels in semen on sperm quality.MethodsThe subjects involves 78 males, 25- to 35-year old. The samples were divided into a low group (Mφ < 6 × 105/ml) and a high group (Mφ > 6 × 105/ml). Evaluation included consideration of the influencing factors of male semen quality, macrophage concentration, sperm motility, morphology, membrane integrity DNA fragmentation index (DFI), anti-sperm antibodies (AsAb), IL-10, and IL-12 in semen.ResultsThere was no difference in the physical or chemical indices of the semen, sperm concentration, AsAb, IL-10, or IL-12 between the two groups (P > 0.05). The percentage of sperm forward motility (PR%), the rate of normal sperm shape, and the integrity of cell membranes in the low group were higher than those in the high group (P < 0.05), while the percentage of sperm inactivity (IM%), the rate of sperm head deformity, the rate of deformity in the neck and middle segment, the sperm deformity index (SDI), the teratozoospermia index (TZI), and the sperm DFI in the low group were lower than those in the high group (P < 0.05). The concentration of Mφ in the semen was linearly correlated with sperm concentration, sperm PR%, IM%, sperm normal shape rate, head deformity rate, neck and middle deformity rate, SDI, TZI, sperm DFI, and sperm cell membrane integrity (P < 0.05), but there was no linear correlation with IL-10 or IL-12 (P > 0.05).ConclusionsThe Mφ concentration in semen is not significantly correlated with semen volume or sperm concentration, but negatively correlated with sperm motility, morphology, cell membrane integrity, and DNA damage rate. There is no significant correlation between the macrophages and the concentration of IL-10 or IL-12.

Correction of deformity associated with healed slipped capital femoral epiphysis by Imhäuser osteotomy

Slipped Capital Femoral Epiphysis is the leading cause of limp in the adolescent population. This study aimed to discuss that intertrochanteric Imhauser osteotomy led to an improved functional outcome, and discussing indications, contraindications and surgical technique of Imhauser osteotomy.In moderate and severe slips, residual growth and remodeling after in situ stabilization are unable to compensate for the remaining femoral neck deformity. In these slips, a modified Dunn procedure might be more effective in order to reduce the risk of early onset hip osteoarthritis but carries high risk for avascular necrosis.Subtrochentric Imhauser osteotomy provides excellent option for correction of the residual deformities in chronic or healed SCFE.The Imhauser osteotomy is Subtrochentric valgus, flexion and internal rotation so correct the deformities in the chronic cases of SCFE. In consideration of our 23-year follow-up and in regard to other studies, we still consider the Imhauser ¨user osteotomy to be indicated for SCFE with angles of displacement >40°.

A single K-wire to prevent poor outcomes in closed soft-tissue mallet finger management due to patient non-compliance.

Soft-tissue mallet finger occurs due to loss of terminal extensor tendon secondary to rupture of distal phalanx. Although using noninvasive splints for 6-8weeks is the gold standard for conservative treatment of closed soft-tissue mallet injuries, patient compliance is an important factor impacting on patient outcomes. In this study, we used a single Kirschner Wire (K-W) to fix the distal interphalangeal (DIP) joint in extension in those patients failed to comply with routine splinting. In this prospective study, 190 patients with Doyle type 1 closed soft-tissue mallet finger deformity were included in four groups between 2011 and 2015. These groups were determined according to treatment modalities. Patients in the first group were treated with a finger splint (n = 109). Patients in the second group first received a finger splint and then K-W was applied due to lack of adequate compliance (n = 23). Patients in the third group were treated with K-W only (n = 47), and the fourth group did not accept surgical treatment nor conservative treatment (n = 11). After 20weeks of follow up, we evaluated the results with functional measurements according to Crawford criteria and patient satisfaction. Additionally, the mid-term outcome was assessed with a follow-up at 2years. At 20th week postoperatively, average DIP extension lag was 6 degrees (0-30) for the first group, 6.1 degrees (0-30) for the second group, 3.8 degrees (0-25) for the third group, and 17.3 degrees (7-30) for the fourth group. Total patient satisfaction was 85%, which was considered excellent or good. Swan neck deformity was observed in 11% of patients. Osteomyelitis and KW related complications were not observed. There were no statistically significant differences between short-term and mid-term results. Internal fixation via K-W may be a suitable treatment option compared to splint therapy for management of closed soft-tissue mallet finger in noncompliant patients. Using this treatment approach, the success rate for patients could satisfactorily be improved.

A Sudanese Male with Jaccoud’s Arthropathy; Case Report

JA is a non-erosive deforming form of arthropathy that is characterized by correctable joint deformities such as ulnar deviation, thumb subluxation and swan neck deformity...

Tumescent local anesthesia as an alternative to general anesthesia in release of post-burn neck contracture and skin graft harvesting: A comparative study

Background: Anesthetic management of severe post burn neck contracture is difficult, demanding due to fixed flexion deformity of neck, incomplete oral occlusion and insufficient mouth opening leading to difficulty in intubation. Patients undergoing contracture release, skin graft harvest under general anesthesia (GA) were compared with patients undergoing the same surgery under tumescent local anesthesia (TLA) technique.&#x0D; Methodology: Twenty-one patients with post burn neck contracture undergoing contracture release with split skin grafting under GA were compared with twenty-one patients undergoing the same surgery under TLA. Post-operative pain and satisfaction were assessed using 10 cm VAS (Visual Analogue Scale).&#x0D; Results: Demographic profile was comparable in both groups. Changes in intra-operative vital parameters remained insignificant. The average volume of tumescent solution used was 254.76 + 49.05ml. Blood loss was significantly decreased, postoperative pain relief was more than sixteen hours in thirteen patients and extended beyond twenty-four hours in six patients in the TLA group. Time for the first rescue analgesia was significantly lesser in the GA group and the average dose of injection tramadol used in the GA group was significantly higher within the first 24 h. Overall satisfaction in the TLA group was significantly higher than in the GA group.&#x0D; Conclusion: TLA can be used as sole technique for release of post burn neck contracture and harvest of split skin grafts with less blood loss and significantly better postoperative pain relief avoiding complications of general anesthesia.&#x0D; Key words: Tumescent local anesthesia; Post burn neck contracture; Skin graft harvest; General anesthesia&#x0D; Citation: Prasad MK, Jain P, Varshney RK, Khare A, Jheetay GS. Tumescent local anesthesia as an alternative to general anesthesia in the release of post-burn neck contracture and skin graft harvesting: A comparative study. Anaesth. Pain intensive care 2021;25(1):34–39.&#x0D; DOI: 10.35975/apic.v25i1.1434&#x0D; Received: 18 February 2020, Reviewed: 16 March 2020, Accepted: 30 April 2020

Role of prenatal imaging in the diagnosis and management of fetal facio-cervical masses

Congenital facio-cervical masses can be a developmental anomaly of cystic, solid, or vascular origin, and have an inseparable relationship with adverse prognosis. This retrospective cross-sectional study aimed at determining on the prenatal diagnosis of congenital facio-cervical masses, its management and outcome in a large tertiary referral center. We collected information on prenatal clinical data, pregnancy outcomes, survival information, and final diagnosis. Out of 130 cases of facio-cervical masses, a total of 119 cases of lymphatic malformations (LMs), 2 cases of teratoma, 2 cases of thyroglossal duct cyst, 4 cases of hemangioma, 1 case of congenital epulis, and 2 cases of dermoid cyst were reviewed. The accuracy of prenatal ultrasound was 93.85% (122/130). Observations of diameters using prenatal ultrasound revealed that the bigger the initial diameter is, the bigger the relative change during pregnancy. Magnetic resonance imaging (MRI) revealed that 2 cases of masses were associated with airway compression. In conclusion, ultrasound has a high overall diagnostic accuracy of fetal face and neck deformities. Prenatal US can enhance the management of ambulatory monitoring and classification. Furthermore, MRI provided a detailed assessment of fetal congenital malformations, as well as visualization of the trachea, presenting a multi-dimensional anatomical relationship.

Ellis-Van-Creveld Syndrome and Congenital Cardiac Anomaly: Common Atrium with Atrioventricular Canal Septal Defect

Background: Children presenting with physical features of chondro-ectodermal dysplasia (Ellis-Van Creveld syndrome) such as skeletal and joint abnormalities often have concomitant congenital cardiac anomalies. Presence of cardiorespiratory symptoms in children with Ellis-Van Craved syndrome warrants a thorough cardiologic evaluation to recognize and treat underlying congenital heart anomaly. Aim: A child with physical stigmata of Ellis-Van-Creveld syndrome is evaluated to detect an associated congenital cardiac anomaly and accomplish successful repair of the underlying cardiac lesion to reduce the cardiac related morbidity and improve the patient survival. Case Presentation: Ten years old boy with chondroectodermal dysplasia (dental anomalies, genu valgum and other skeletal abnormalities) presented with dyspnea and cyanosis. Cardiac evaluation by 2D echo revealed an atrioventricular (AV) canal septal defect with AV valve regurgitation and a common atrium. Angiocardiography showed a goose neck deformity of the left ventricular outflow tract. The Qp/Qs was 3.4: 1, with systemic arterial oxygen desaturation (SaO2 of 0.7) and O2 saturation in the common atrium was 0.7. The pulmonary venous connections to the common atrium were anomalous. Atriotomy on cardiopulmonary bypass and on a cardioplegic arrest discerned a partial AV canal septal defect with a common bridging leaflet, clefts in septal leaflets of tricuspid and mitral vlalves, an incompletely closed interventricular communication, and a common atrium with highly anomalous pulmonary venous insertions well anterior (8 cm) to vena caval orifices. Intracardiac repair was performed with two patches of Goertex to partition the common atrium into the pulmonary and systemic venous chambers after repair of the partial AV canal septal defect. Patient required only a temporary afterload reduction with enalapril; otherwise patient had an uneventful postoperative course. At a 2-year follow-up, the child was well without AV valve regurgitation and had normal biventricular function. Conclusion: A child with Ellis-Van-Creveld syndrome with skeletal abnormalities and dental anomalies had manifested with cardio-respiratory symptoms. Preoperative cardiac and intraoperative evaluation showed a common atrium with severely anomalous pulmonary venous connection and partial AV canal septal defect. Successful biventricular repair was accomplished by repairing the partial AV canal septal defect and partitioning the common atrium into left and right atrium by a complex atrial routing technique with two patches of Gore-Tex. On a follow-up at 2 years, the patient had adequate biventricular function without AV valve regurgitation. 114264

PATIENT-REPORTED OUTCOMES FOR USE OF SILVERSPLINTS IN OSTEOARTHRITIS OF THE HAND.

Pain, stiffness and joint deformity can result in significantly reduced hand function in people with osteoarthritis. Characteristic finger deformities in osteoarthritis are swan neck deformity and boutonnière deformity. Several studies have reported that an orthosis decreases pain and increases function during daily activities for patients with arthritis. The aim of this study was to review patient-reported outcomes of current conservative therapeutic management with silver ring splints (silversplints) for patients with osteoarthritis of the hand. There was a 76% improvement in overall daily functioning and a 74% reduction in pain. Several questions concerned daily activities with different types of hand function and with different types of grip and use of fingers. The results show a major improvement in both the more open grip of the hand and activities requiring fine motor skills. The ability to use force with the hand, even when wearing an orthosis, is an important result. Patients who experienced “no problems or minor problems” had significantly increased functioning in several activities of daily living, but the largest improvement in functioning was seen in “household chores” (243%), “opening jars” (150%) and “lifting groceries” (143%). Overall, silversplints appear to serve as a suitable support for the joints in osteoarthritis of the hand, providing pain relief by preventing the joint from moving through its full range of motion. Use of silversplints to treat patients with osteoarthritis of the hand should be considered as a useful, non-surgical method.LAY ABSTRACTThis study of patient-reported outcome measures regarding the use of silversplints for osteoarthritis of the hand provides insight into the additional care and quality of life provided by the use of an orthopaedic medical aid. The aims of this study are to measure the effectiveness of silversplints in daily life and to validate the efficacy of using orthopaedic medical aids. Between October 2018 and June 2020, a total of 2,231 patients with osteoarthritis were provided with silversplints and were asked about the effectiveness of the splints 3 weeks after they first started wearing them. This large-scale study found that the use of silversplints contributed to overall daily functioning, reduced pain, and increased the possibility of performing daily activities. Silversplints appear to serve as a suitable support for joints, providing pain relief and freedom of movement, but preventing the joint from moving through its full range of motion.

An overview of mallet finger injuries.

Mallet finger describes a fingertip deformity where the distal interphalangeal joint (DIPJ) of the affected digit is held in flexion, unable to extend the distal phalanx actively. The deformity is typically a consequence of traumatic disruption to the terminal extensor tendon at its insertion at the proximal portion of the distal phalanx or slightly proximally at the level of the DIPJ. Patients typically present with a history describing the event of injury with a typical mallet deformity. Common mechanisms include sport activities causing a direct blow to the finger, low energy trauma while performing simple tasks such as pulling up socks or crush injuries from getting the finger trapped in a door. The DIPJ can be passively extended, but this extension of the joint cannot be maintained once the passive extension is stopped. The Doyle classification can be used to categorise and dictate treatment. The extensor lag associated with the deformity does not improve spontaneously without treatment. Inappropriate management can lead to chronic functional loss and stiffness of the finger. The majority of closed mallet splints are Doyle type I, which can be managed non-surgically with external splints, worn full-time to keep the fingertip straight until the tendon injury or fracture heals. Surgical techniques is considered for other types of mallet injuries. Techniques used include closed reduction and Kirschner wire fixation, open reduction and internal fixation, reconstruction of the terminal extensor tendon and correction of swan neck deformity. (www.actabiomedica.it)

The Dynamic Thumb-in-Palm Pattern in Children with Spastic Cerebral Palsy and Its Effects on Upper Limb Function.

The thumb-in-palm (TIP) pattern is one of the most common upper limb deformities in cerebral palsy (CP). This study was designed to investigate the effect of the dynamic TIP pattern on upper limb function in children with spastic CP. This prospective observational study included a total of 106 children with CP with dynamic TIP. The House TIP classification while grasping small or large objects, Melbourne Assessment of Unilateral Upper Limb Function (MUUL), Shriners Hospital Upper Extremity Evaluation (SHUEE), Zancolli classification for wrist–finger flexor deformity, and degree of swan neck deformity were assessed. Type I was the most common and highest functioning House TIP classification type. However, there were no significant differences in upper arm function between types II, III, and IV. The three components of the SHUEE showed stronger association with MUUL than House TIP and Zancolli classifications. After multivariable analysis, functional use of the wrist–finger and the thumb played a more significant role than the dynamic alignment of the thumb. In conclusion, the House TIP classification is useful to describe the TIP pattern. The SHUEE thumb assessment is a useful tool for reflecting upper arm function. The upper arm function was related more with the associated wrist flexor deformity than dynamic TIP.

Macroscopic and microscopic characterizations of Portevin-LeChatelier effect in austenitic stainless steel using high-temperature digital image correlation analysis

Using digital image correlation (DIC) analysis in an Fe-19Cr-13Ni-0.2C austenitic stainless steel (mass%), the tensile deformation behavior accompanied with the Portevin-LeChatelier (PLC) effect was investigated at high temperatures of 723-823 K under various applied strain rates of 10−4 s−1–5 × 10−3 s−1. With the help of the DIC analysis, the global strain in the gauge part of a tensile specimen and the local strain in a PLC band were precisely measured regardless of the lowering machine stiffness at a high temperature. The high-temperature DIC analysis could identify the critical strain and strain rate conditions where stress-strain curve indicated serrated flow. The analytical results revealed that dynamic strain aging in the austenitic stainless steel was controlled by the pipe diffusion of Cr atoms. Further, it was also confirmed that the local strain gently increased in a gauge part through a PLC band propagation, which promoted a repeatable A-type PLC band propagation in the same direction. Furthermore, the local strain was discontinuously developed by the repeatable formation of PLC bands; consequently, the local strain rate became remarkably high within a PLC band. In addition, the local strain rate in the PLC band monotonically increased with the increase in the number of PLC bands. From this viewpoint, it was discovered that necking deformation occurs suddenly at the PLC band, when the local strain rate exceeds the critical value, where dynamic strain aging is ineffective.

Development of an In Vitro Swan Neck Deformity Biomechanical Model.

Injury to the finger's extensor mechanism is a common cause of swan neck deformity (SND). Progression of extensor and flexor tendon imbalance negatively affects laxity of the volar plate, resulting in the inhibition of proper finger motion. The complexity of finger anatomy, however, makes understanding the pathomechanics of these deformities challenging. Therefore, development of an SND model is imperative to understand its influence on finger biomechanics and to provide an in vitro model to evaluate the various treatment options. The index, middle, and ring fingers from 8 cadaveric specimens were used in an in vitro active motion simulator to replicate finger flexion/extension. An SND model was developed through sectioning of the terminal extensor tendon at the distal insertion (creating a mallet finger) and transverse retinacular ligament (TRL). A strain gauge inserted under the volar plate measured laxity of the plate, and electromagnetic trackers recorded proximal interphalangeal joint (PIPJ) angles. Strain in the volar plate increased progressively with creation of the mallet and SND conditions (P = .015). Although not statistically significant, the mallet finger condition accounted for 26% of the increase, whereas sectioning of the TRL accounted for 74% (P = .031). As predicted, PIPJ hyperextension was not detectable by joint angle measurement; however, the PIPJ angle had a strong positive correlation with volar plate strain (R2 = 1.0, P < .001). Volar plate strain measurement, in an in vitro model, can detect an induced SND. Moreover, as a surrogate for PIPJ hyperextension, volar plate strain may be useful to evaluate the time-zero effectiveness of various surgical interventions.

Hardening model of anisotropic sheet metal during the diffuse instability necking stage of uniaxial tension

In order to determine the stress–strain response in the diffuse necking for low carbon steels, the evolution of the diffuse necking region and the distributions of stress and strain in the narrowest cross-section are analyzed comprehensively based on 3D-DIC and FE simulation. Three parabolic functions are adopted to simplify the diffuse necking deformation: the shape of the necking region is parabolic, the distributions of stress and strain in the narrowest cross-section are also parabolic. A hardening model for solving the uniaxial tensile true stress and strain in the diffuse necking is established. Uniaxial tensile tests of four kinds of low carbon steel sheets and three typical anisotropic directions have been carried out to verify the reliability of the developed model. The numerical simulation results show that the uniaxial tensile load–elongation curves based on the hardening model are in good agreement with the experimental results, with an error of less than 1.3%. The true stress and strain in the diffuse necking can be determined easily by interpreting the tensile curve and measuring the shape of necking region. It avoids the difficulty and time-consuming of the inverse methods. This study can provide a valuable reference for establishing theoretical models to acquire true stress–strain curves over large range of strains for anisotropic sheet metals.

Preoperative Planning for the Foot and Ankle: A Technique Tip

Category:Other; Ankle; Midfoot/ForefootIntroduction/Purpose:Computed tomography (CT) advanced imaging techniques are a valuable tool for orthopedic surgeons when evaluating complex foot and ankle pathology. With advances in CT data processing, surgeons can create custom reformation of the imaging data in real time using postprocessing imaging tools. This article presents a technique describing how to manipulate CT data using two of these tools, multiplanar reformation (MPR) and maximal intensity projection (MIP), to better visualize pathology and allow a more definitive diagnosis preoperatively. Despite their availability on most modern picture archiving and communication systems, most surgeons across orthopaedics disciplines fail to utilize these powerful tools.Methods:Patients with complex midfoot deformities underwent CT scans for diagnosis and preoperative planning. Case 1 underwent percutaneous pinning of multiple metatarsal fractures. Post-operatively she had severe pain localized to the second and third metatarsals. A CT scan obtained in standard axes failed to interpret the multiplanar deformities when viewed initially on PACS. Using MPR/MIP, the axes were rotated to generate a detailed view of the deformities and subsequently template osteotomies. Case two underwent arthrodesis of the second and third tarsometatarsal (TMT) joints for an unstable Lisfranc injury. Post-operatively she presented with severe midfoot pain prohibiting her return to athletics. Radiographs demonstrated normal alignment with hardware obscuring the joints. Standard CT axes were difficult to interpret due to metal artifact and oblique planes of the TMT joints. MPR/MIP reformatting allowed metal artifact reduction through axes adjustment, improving visualization and facilitating diagnosis of nonunion of the second and third TMT fusions.Results:Case One:MIP/MPR allowed manipulation of the CT scan in the axial and coronal planes provided a sagittal reformat of the entire second and third metatarsals. The second metatarsal had a gradual plantarflexion malunion of the diaphysis. The third metatarsal had an acute plantarflexed deformity of the metatarsal neck. Reformatting provided an accurate preoperative template for planned dorsiflexion osteotomies. Case Two: Metal artifact and the oblique orientation of the TMT joints prevented evaluation of previous fusions. MIP/MPR reformatting provided axes which were perpendicular to the TMT joints decreased metal artifact and demonstrated nonunion of the previous fusions. Use of MIP/MPR in this case provided valuable diagnostic information regarding the source of pain and a plan for removal of hardware and revision TMT fusions.Conclusion:The MPR/MIP function is available in most PACS systems and allows customizable CT reformats. The technique is easy to learn and can be done quickly in the office or pre-operative setting. The technology has facilitated streamlined pre- operative planning and improvements in injury visualization numerous times, particularly in complex deformities and trauma. Using MIP/MPR reformats, the authors have been able to identify critical fracture lines and relationships between anatomic structures which may otherwise have been missed or less precisely understood. The authors hope that this article will enhance awareness and encourage others to utilize this powerful technology.

A lumped parameter model for strip-shaped dielectric elastomer membrane transducers with arbitrary aspect ratio

Dielectric elastomer (DE) membrane transducers allow to achieve large strain, low energy consumption, low-noise, and highly compact mechatronic devices. To optimize the design of membrane DEs via numerically efficient software tools, as well as to develop accurate control and self-sensing algorithms, a lumped parameter model is required. In the case of rectangular DE strips clamped at both ends and subject to a uniaxial in-plane load, the resulting necking and inhomogeneous deformation turn out to be challenging to be described via standard lumped models, thus making it necessary to rely on numerically involved finite element (FE) tools. In this paper, we present a novel modeling framework that permits to accurately describe clamped DE membranes with generic aspect ratio in a control-oriented fashion. The model is grounded on an anisotropic free-energy function, which maps the inhomogeneities due to clamping within the constitutive membrane behavior. In this way, a lumped description of the DE can be obtained in terms of average stress and stretch quantities. After presenting the model, an extensive validation is performed by means of comparative studies with FE simulations as well as experimental results. It is observed how the proposed model permits to accurately describe the electro-mechanical response of clamped DE membranes for a wide range of aspect ratios, including nearly-uniaxial, nearly-pure shear, as well as intermediate configurations.

A full-range stress-strain model for metallic materials depicting non-linear strain-hardening behavior

Ramberg-Osgood (R-O) type stress-strain models are commonly employed during elasto-plastic analysis of metals. Recently, 2-stage and 3-stage R-O variant models have been proposed to replicate stress-strain behavior under large plastic deformation. The complexity of these models increases with the addition of each stage. Moreover, these models have considered deformation till necking only. In this paper, a simplistic multi-stage constitutive model is proposed to capture the strain-hardening non-linearity shown by metals including its post necking behavior. The constitutive parameters of the proposed stress-strain model can be determined using only elastic modulus and yield strength. 3-D digital image correlation was used as an experimental tool for measuring full-field strains on the specimens, which were subsequently utilized to obtain the material parameters. Our constitutive model is demonstrated with an aerospace-grade stainless steel AISI 321 wherein deformation response averaged over the gauge length (GL) and at a local necking zone are compared. The resulting averaged and local material parameters obtained from the proposed model provide interesting insights into the pre and post necking deformation behavior. Our constitutive model would be useful for characterizing highly ductile metals which may or may not depict non-linear strain hardening behavior including their post necking deformations.

Study on the protective effect of hydroalcoholic Olive Leaf extract (oleuropein) on the testis and sperm parameters in adult male NMRI mice exposed to Mancozeb

This study aimed to assess the protective effects of the Olive Leaf Extract (OLE) against Mancozeb (MZB)-induced reproductive damage in male NMRI mice.In this experimental study, NMRI mice were randomly divided into 7 groups (n = 8) including 1: control, 2: MZB, 3: MZB + OLE (200 mg/kg), 4: MZB + OLE (400 mg/kg), 5: MZB + atropine (0.25 mg/kg), 6: OLE (200 mg/kg) and 7: OLE (400 mg/kg). Mice were sacrificed after 5 weeks, and blood samples were drawn to measure serum testosterone level. Sperm samples were collected and analyzed according to standard criteria. The left testis was removed to assess testicular parameters using H&E staining. The Protamine level and DNA fragmentation were determined by chromomycin A3 (CMA3) and SCD assays, respectively.Sperm viability decreased in MZB- induced groups. Also, the sperm's protamine deficiency (higher than 30%) and DNA fragmentation increased within MZB induced. There were significantly higher structural deformities of sperm's head, neck, and tail in MZB-treated groups as well (p < 0.05).Within treated groups with OLE, these sperm factors could repair defects versus MZB group. Furthermore, there were significant differences comparing sperm motility (type A, B, and D); protamine level, DNA fragmentation (SCD1, SCD3, and SCD4), and testosterone levels compared to the groups (p < 0.05). Sperm motility, seminiferous tubules diameter, the height of the germinal epithelium, and testosterone level within OLE 200 mg/kg was higher than other groups, while these factors in OLE 400 mg/kg was less than OLE 200 mg/kg.Results showed that oral administration of OLE could be useful in ameliorating MZB induced toxicity in the reproductive system of male mice within 200 mg/kg dosage; while OLE 400 mg/kg probably could exacerbate the harmful effects.