Different intraoperative joint laxity patterns do not impact clinical outcomes in robotic-assisted medial unicompartmental knee replacement with 1-to-1 surface reconstruction.

PURPOSE: Robotic-assisted technology in medial unicompartmental knee arthroplasty (mUKA) allows for customized adjustments of joint laxity through virtual preoperative component positioning before bone preparation. Nevertheless, the optimal balancing curve has yet to be delineated. This study sought to investigate if varying intraoperative knee laxity patterns had any impact on postoperative patient outcomes. MATERIALS AND METHODS: A retrospective analysis was conducted on prospectively collected data from 326 fixed-bearing RAUKA procedures performed between 2018 and 2022 with a minimum 2-year follow-up. Patients were categorized into three cohorts based on intraoperative joint laxity patterns (millimetres of joint gap during valgus stress) imparted at 20°, 60°, 90° and 120° of knee flexion: cohort 1 < +0.5 mm (tight); cohort 2 between 0.6 and 1.9 mm (physiologic); cohort 3 > 2 mm (loose). Wilcoxon and Kruskal-Wallis tests were conducted to assess patient-reported outcome measure (PROM) improvements and preoperative and postoperative differences across the cohorts. A Spearman's test evaluated the correlation between knee balance at all degrees of flexion and preoperative and postoperative HKA. RESULTS: No differences in preoperative and postoperative PROMs were identified across the cohorts (p > 0.05). All three cohorts with different joint laxity patterns showed a significant improvement in the postoperative PROMS (p < 0.05). The preoperative or postoperative limb alignment did not significantly affect clinical outcomes relative to different laxity patterns. CONCLUSION: No differences were found in the outcomes across different joint laxity patterns in robotic-assisted medial UKA using fixed-bearing mUKAs. There was no evident advantage for maintaining a closer to physiologic laxity compared to tighter or looser balancing. LEVEL OF EVIDENCE: Level III therapeutic study.

Long-term outcomes of sequential chemotherapy in epithelioid sarcoma.

Our study was carried out to define the efficacy of treatment with sequential chemotherapy lines in patients with epithelioid sarcoma (ES) at referral centres for sarcoma. From 1998 to 2023, 22 patients with ES were treated with chemotherapy and included in the analysis. The median age at the start of palliative treatment was 35 (20-68). The median follow-up was 22.1 months. In the first line, 13 patients (59%) received anthracycline-based chemotherapy and 6 (27%) high-dose ifosfamide. One patient (4.5%) achieved PR, 15 (68%) SD, and 6 (32%) PD as the best response. The median progression-free survival (PFS) in the first line was 6.4 months (95% CI: 3.02-12.9), but 9.7 months (95% CI: 4.37-NR) for chemotherapy based on anthracycline, indicating a more favourable PFS (p = 0.027). Twenty (90%) patients received second-line treatment, and eleven received third-line chemotherapy. The median OS from the start of first-line palliative chemotherapy was 22.1 months (95% CI: 10.5-41.4) and 14.7 months from the beginning of the second line. Perioperatively, patients pretreated with anthracycline had a median PFS of 2.9 months in the M1 setting. Second-line long-time responses were achieved with pazopanib or vincristine with actinomycin D. Despite chemoresistance, an advantage associated with anthracycline-based chemotherapy was confirmed in the ES cohort. Poor responses underscore the need for further research on targeted therapies for ES. Second-line chemotherapy or clinical trials should be offered to all eligible patients.

Ectomesenchymal Chondromyxoid Tumor of the Anterior Tongue: A Case Image.

Ectomesenchymal chondromyxoid tumor (ECT) is a rare soft tissue tumor with peculiar histogenesis, exhibiting a predilection for the dorsum of the tongue. Molecular evidence suggests that it may originate from the migration of ectomesenchymal pluripotent cells from the neural crest to the tongue, where these cells may eventually proliferate and undergo myxoid and chondroid differentiation. This article illustrates a case of a 16-year-old female patient who presented with a nodule on the dorsum of her tongue, which had been present for four years. Surgical excision was performed, and histopathological analysis revealed a myxoid neoplasia composed of polygonal and spindle cells within a loose stroma containing chondroid areas. Tumor cells were positive for GFAP and S-100 proteins on immunohistochemical study, confirming the diagnosis of ECT. After a 5-year follow-up, the patient has shown no evidence of recurrence. Although rare, ECT can be diagnosed straightforwardly due to its distinctive clinical, histopathological, and immunohistochemical features. Clinicians and pathologists should become familiar with this tumor in order to avoid misdiagnosis.

Perforator-based local flaps for cutaneous facial reconstruction.

BACKGROUND: Despite the advancement of reconstructive surgical techniques, facial defect reconstruction has been always very challenging, aesthetic satisfaction has often been difficult to achieve due to the unique characteristics and complexity of the facial tissue. There have been various options regarding reconstruction and compensation of soft tissue loss all over the body rather than the face. Regardless of whether skin grafts, local flaps, and free flaps were used in the reconstruction process, each of them has its limitations. Beginning with skin grafts results could not always be satisfactory due to contracture, color, and lack of texture Additionally, local flaps have limitations due to mobility and the availability of overlapping skin and tissue, as well as the bulkiness of the pedicle which may need a second staged surgery and lately the difficulty of the free flaps and being a major surgery. RESULTS: Patients ages ranged between 23 and 77 years old, with a mean age of 58.33 ± 12.47. As regards the patients' sex, 63.3% of our patients were males and 36.7% were females. Co-morbidities were found in 60% of cases (DM 23.3%, HTN 20%, HCV 3.3%, cardiac 3.3%). Most flaps were facial artery perforator flaps 53.3%, then transverse facial artery 26.7%, superficial temporal artery 10%, angular artery 6.7%, and supra-trochlear artery 3.3%. Twenty-ix cases representing 86.7% of cases went uneventful, while complications showed in 4 cases representing 13.3% of cases, 1 case (3.3%) showed venous congestion that was relieved within 24 h after 2 suture releases, another case (3.3%) showed wound dehiscence that was improved after 2 days with regular dressings, the third patient (3.3%) had recurrence after 4 months that was treated by excision and grafting, while last patient (3.3%) had inadequate excision that was treated by radiotherapy. No bleeding or infection occurred. Also, we observed no correlation between flap length and complications. As regards the functional point of view, all patients showed no functional impairment at the donor site, and only one case showed functional impairment at the recipient site. As regards patient satisfaction, all 30 patients achieved positive satisfaction scores using the Likert scale, 18 cases were satisfied, and 12 cases were very satisfied. CONCLUSION: The use of perforator-based flaps can provide a more effective and aesthetically pleasing solution for the reconstruction of small to moderate facial defects, provided that a reliable Perforator is accurately identified and executed by an experienced surgeon.

Minimally Invasive Surgery For Management of Bunionette Deformity (Tailor's Bunion) Using Fifth Metatarsal Osteotomies: A Systematic Review and Meta-Analysis.

Background: There has been increasing interest in the use of percutaneous or minimally invasive osteotomy techniques for bunionette correction. The aim of this systematic review was to investigate the clinical and radiographic outcomes following percutaneous or minimally invasive surgery for bunionette deformity correction. Methods: A systematic review following PRISMA guidelines was undertaken. All clinical studies published in MEDLINE, Embase, PubMed, and the Cochrane Library Database from inception until December 2023 reporting on the use of percutaneous or minimally invasive osteotomy techniques for bunionette deformity correction were included. The primary outcome was radiographic deformity correction. A meta-analysis of clinical and radiographic outcomes was performed to assess the mean difference following surgery. Risk of bias was assessed using the ROBINS-I tool. Results: A total of 942 potential studies were identified, of which 18 were included encompassing 714 feet in 580 patients. There were no comparative studies identified. The majority of studies (n = 14/18) used an unfixed distal osteotomy technique. All studies showed a statistically significant improvement in clinical outcomes (American Orthopaedic Foot & Ankle Society ankle-hindfoot score and visual analog scale for pain) and radiologic outcomes (fourth-fifth intermetatarsal angle and fifth metatarsophalangeal angle). Complication rates ranged from 0% to 21.4%. The nonunion rate was 0% to 5.6%. Overall risk of bias was low to moderate. The most common complication was development of a hypertrophic callus that tended to resorb over time without needing further surgical intervention. Conclusion: The results of this systematic review must be considered in light of the methodologic limitations of the studies analyzed-including additional procedures performed at the same time as the bunionette correction, lack of comparative studies, and heterogeneity of the case series included. Despite these limitations, our review suggests that percutaneous techniques for bunionette deformity correction are generally clinically safe and associated with improvement in radiographic alignment and patient-reported outcome measures.

Bone and Soft Tissue Sarcoma Epidemiology in Iranian Elderly Population; an Analysis of the Iranian National Registry for Cancer (2009-2014 Years).

Background: We aimed to investigate the patterns of incidence and prevalence of bone sarcoma (BS) and soft tissue sarcoma (STS), morphology as well as geographical distribution in the elderly in Iran. Methods: By the primary site of the tumor and the morphological types, whole cases of cancer were classified. Then, the WHO classification (2018) and the third revision of the standard International Classification of Diseases for Oncology (ICD-O-3) were used to assign a code to them. The estimated incidence rates were obtained as the frequency of the newly-diagnosed cases within one year divided by the calculated population of the mid-year Iranian residents as estimated by the Iranian Bureau of Statistics. The age-standardized incidence rates were also estimated for both bone and soft tissue sarcoma. Results: The annual crude incidence rates of sarcomas in males (0.80 per 100,000) were more than in females (0.55 per 100,000) in all years. The total combined crude incidence in 2014 years was obtained at 0.67 per 100,000 people. In terms of disease grade majority of the patients were of grade 3 (11.5 %). In terms of tumor location, the Lower extremity was 16.8%, the Visceral (including gastrointestinal & uterus) 15.8%, the Thoracic 12.8%, and the Pelvic & abdominal wall 9.7%. Conclusion: Even though such sarcoma is more prevalent in elderly men, its incidence was also observed in lower-aged female groups. In addition, the incidence rate of BS was lower in comparison with that of STS, and the patients often exhibited an unknown degree of sarcoma.

Correlation Between Planned and Executed Bone Cuts Using Robotics in Total Knee Arthroplasty: A Prospective Study of 500 Patients.

Objective: This study evaluated the precision of robotic-arm-assisted total knee arthroplasty (RATKA) in performing bone resection, predicting component size, managing soft tissue tension, and determining postoperative range of motion (ROM). Methods: A total of 500 participants were enrolled in this prospective cohort research. The procedures were conducted at a single facility, with a uniform method and implant design. The Cuvis system, a fully automated robot, was utilized for the study. The precise removal of bone at both the tibial and femur sites, the positioning of the implant, and the release of soft tissue were documented and then compared to the preoperative plan. Results: The distal (medial and lateral) femoral cuts had a mean absolute deviation from the plan of 0.23 mm, while the posterior (medial and lateral) femoral cuts had a mean absolute difference of 1 mm and 1.4 mm, respectively. The absolute discrepancies in the medial and lateral tibial cuts are 0.93 mm and - 0.06 mm, respectively. Out of 1000 bone resections, 980 (98%) were within < 1 mm from the preoperative plan. The predictions for the sizes of the tibial and femoral components had accuracies of 100% and 98.9%, respectively. Conclusion: These findings collectively underscore the effectiveness of the fully automated Cuvis robotic system in achieving consistent and accurate results in bone resections and implant sizing, highlighting its potential as a valuable tool in orthopedic surgery.

Tibiofemoral axial rotation in tibial plateau fractures: A retrospective radiographic assessment of 203 tibial plateau fractures.

BACKGROUND: Defining the injury-force mechanism in tibial plateau fractures (TPFs) could help define implant type and position, as well as soft tissues at risk. The aim of this study was to provide an analysis of injury-force-mechanisms in TPFs, including axial rotation. METHODS: The injury-force mechanism was determined for 203 fractures that presented over a period of 3.5 years. Fractures were classified as flexion-varus/valgus/neutral or (hyper)-extension-varus/valgus/neutral by observing articular depression area on CT/MRI. Fractures were subclassified into rotation-neutral, internal- or external-rotation according to the Gerdy-tibial-tuberosity-surgical-epicondylar-axis (GTT-SEA) angle. Soft-tissue injury was documented if MRI was performed. RESULTS: Flexion-valgus was the most common injury-force mechanism (n = 85, 41.9%), followed by extension-valgus (n = 57, 28.1%). Other mechanisms were less common (9.4% extension-varus, 5.9% flexion-neutral, 4.9% flexion-varus, 3.9% hyperextension-valgus, 3.4% extension-neutral and 2.5% hyperextension-varus). The GTT-SEA angle could be measured in 194 (95.6%) of 203 classified patients, revealing internal rotation in 83 (42.8%) and external rotation in 53 (27.3%). No significant difference was found between injury-force mechanism type and axial rotation group (P = 0.964) or extent of rotation (H(8) = 7.116, P = 0.524). Only 41 (21.1%) of 194 fully classified fractures underwent MRI, all revealing soft-tissue injury to some extent. High-grade posterolateral injuries occurred mainly in rotated TPF. CONCLUSION: Our results describe the common forms of axial rotation present in TPF and explore their association with injury-force mechanism and soft-tissue injury. Applying the injury-force mechanism patterns and addressing rotational forces could, together with preoperative MRI and intra-operative stability assessment, help determine the need to surgically address associated soft-tissue injury.

Artificial dermal repair for larger finger pulp defects: Satisfactory coverage with limitations in sensation and inevitable scar formation.

BACKGROUND: This prospective study aimed to evaluate the outcomes of the use of dermal templates for lengthy volar soft tissue defects (1.5-4 cm) in the fingers. METHODS: The volar soft tissue defects of 15 patients (19 fingers) were treated with Lando dermal template coverage between June 2022 and November 2022. We evaluated sensory recovery, scar formation, and overall appearance of the repair site at an average of 13 months (range, 12-17 months) of follow-up. RESULTS: The defect healed in all cases. We found an average static 2-point discrimination of 7 mm (range 4 to 14 mm). Scar formation was evident in all cases. The repair did not restore the bulkiness of the volar finger, especially in the finger with the bony exposure. Nail deformities and joint contracture were observed in some cases. CONCLUSION: Dermal template repair does not restore normal sensation and inevitably leads to scar formation when the defect is longer (>1.5 cm). Bulkiness of the volar finger is not restored in most patients, especially when there was bone or tendon exposure in the initial wound site.

A preliminary investigation into the impact of soft tissue augmentation-based periodontal phenotype modification therapy for patients exhibiting class III decompensation.

BACKGROUND: Patients with skeletal angle Class III malocclusion usually have inadequate hard and soft tissue volume at the mandibular anterior teeth. The labial proclination at the teeth may lead to gingival recession. The purpose of this study was to explore whether periodontal phenotype modification therapy with soft tissue augmentation (PhMT-s) can prevent gingival recession in these patients. METHODS: Four patients with skeletal Class III malocclusion and a thin periodontal phenotype underwent surgical-orthodontic treatment. Prior to tooth movement, they underwent a minimally invasive vestibular incision with subperiosteal tunnel access combined with autogenous connective tissue grafts for periodontal phenotype modification with soft tissue augmentation (PhMT-s). The labial gingival thickness of the anterior mandibular teeth was measured at three distinct levels: at the cementoenamel junction (GT0), 3 mm apical to the CEJ (GT3), and 6 mm apical to the CEJ (GT6). These measurements were taken at baseline, three months following PhMT-s, and after tooth decompensation. Additionally, a biopsy sample was obtained from the PhMT-s site of one patient. All sections were subsequently stained using hematoxylin and eosin, Masson trichrome, Sirius Red, and immunohistochemistry. RESULTS: The thickness of the labial gingiva was increased about 0.42 to 2.00 mm after PhMT-s. At the end of pre-orthognathic surgical orthodontic treatment, the thickness of the labial gingiva was increased about - 0.14 to 1.32 mm compared to the baseline and no gingival recession occurred after the pre-orthognathic surgical orthodontic treatment. The histologic results demonstrated that the grafts obtained from the PhMT-s site exhibited increased deposition of collagen fibers. Moreover, the proportion of type III collagen increased and the grafts displayed significantly reduced positive expression of CD31 and OCN. CONCLUSIONS: PhMT-s increased the thickness of the soft tissue, stabilizing the gingival margin for teeth exhibiting a thin periodontal phenotype and undergoing labial movement. This is attributed to the increased deposition of collagen fibers.

Malignant Transformation of Plexiform Neurofibroma Due to Neglected Giant Soft Tissue Swelling of the Back: A Case Report.

Neurofibromatosis type 1 can be severe and associated with malignant transformation. Proper follow-up and monitoring are very important in preventing the malignant transformation of neurofibromatosis. We encountered a case of malignant transformation of plexiform neurofibroma into neurofibrosarcoma (also known as malignant peripheral nerve sheath tumor). She had been presenting with a large mass on her back for a few years, which was also associated with an ulcer. She underwent a wide-excision biopsy of her back, and the histopathology examination (HPE) came back with a malignant peripheral nerve sheath tumor. This case concludes that any patient with a known case of neurofibromatosis should undergo follow-up to detect any malignant transformation of the disease. Early detection of the malignant transformation of neurofibromatosis can help prevent the disease's progression. The main treatment is surgical resection; however, the risk of local recurrence is higher, especially in patients with neurofibromatosis type 1.

Patient-Reported Outcomes After Periodontal Surgical Procedures.

Background Patient satisfaction is the primary focus of the healthcare system. Patient-reported outcome measures (PROMs) are standardized and valid measures obtained directly from the patients and are used to assess and compare the efficacy of healthcare services. This can help improve the service provided by the healthcare system. Therefore, this study aimed to assess PROMs during the first week post-surgery across different periodontal surgical procedures and explore their correlation with surgical duration. Furthermore, the study sought to evaluate the occurrence of postoperative complications. Methodology A total of 30 healthy patients with no systemic history, requiring periodontal surgical procedures such as crown lengthening (CLP), open flap debridement (OFD), and soft tissue grafting (STG) were included in the study. The Visual Analog Scale (VAS) was utilized for gathering PROMs concerning bleeding, swelling, bruising, and pain at intervals of days zero, three, five, and seven after the surgical procedure. Results On the surgical day and over seven days, VAS scores were the lowest for CLP and highest for STG procedures. This result is in accordance with the duration required for surgery. VAS scores for OFD were intermediate. Prevalence of 20% soft tissue graft dehiscence and 40% tenderness on palpation was observed. Swelling and bleeding were noticed in 10% and 20% of OFD cases. Conclusions One week post-surgically, the mean VAS scores were minimum for CLP, whereas maximum for STG procedures. As CLP and OFD require less duration compared to STG, duration plays a significant role in post-surgical outcomes. Prevalence of the post-surgical complications is also related to the duration of the surgery.

Relation between soft tissue energy dissipation and leg stiffness in running at different step frequencies.

This study aims to investigate the relationship between soft tissue energy dissipation and leg stiffness during running. Eight recreational healthy male runners (age: 22.2 ± 1.0 years; height: 1.84 ± 0.03 m; mass: 73.7 ± 5.7 kg) were asked to run at different speeds and step frequencies. Their soft tissue energy dissipation was estimated by the difference between the total mechanical work of the body, measured as the work done to move the body centre of mass relative to the surroundings plus the work to move the limbs relative to the body centre of mass, and lower-limb joint work. A mass-spring model with an actuator was used to analyse the force-length curve of the bouncing mechanism of running. In this way, the stiffness and damping coefficient were assessed at each speed and step frequency. Pearson's correlations were used to describe the relationship between the deviation from the spring-mass model and soft tissue energy fluctuations. The soft tissue dissipation was found to be significantly influenced by step frequency, with both positive and negative work phases decreasing when step frequency increases. Moreover, deviation from a spring-mass model was positively associated with the amount of soft tissue dissipation (r > 0.6). The findings emphasize the substantial role of soft tissues in dissipating or returning energy during running, behaving in a damped-elastic manner. Also, we introduce a novel approach for evaluating the elastic rebound of the body during running. The insights gained may have broad implications for assessing running mechanics, with potential applications in various contexts.

The clinical effects of artificial dermis in the treatment of skin and soft tissue defects accompanied by bone or tendon exposure.

OBJECTIVE: The clinical effects of artificial dermis in treating skin and soft tissue defects accompanied by bone or tendon exposure were assessed. APPROACH: A retrospective analysis was conducted on the clinical data of 45 cases of skin and soft tissue defects accompanied by bone or tendon exposure admitted to the trauma surgery department of Fujian Provincial Hospital between February 2018 and August 2020. They were divided into the artificial dermis and control groups. The wound was assessed using the Vancouver Scar Scale (mVSS), and the postoperative visual analogue scale (VAS) scores were recorded at 3, 6, 9, and 12 months after surgery. At the 12-month after surgery, skin sensation recovery was evaluated using the criteria of the British Medical Research Council (BMRC). RESULTS: The cases included 26 males and 19 females, aged 50 to 85 years. All patients were followed up for an average of 13.8 months (range: 12-18 months). Compared with controls, the wound healing time of the observation group was longer (35.8 ± 10.6 vs. 28.5 ± 4.8, P = 0.007), without significant differences for the number of operations and length of hospitalization. The mVSS scores were not different between groups (Pgroup = 0.294), but the scores decreased with time (Ptime < 0.001), and the group×time interaction was significant (Pinteraction < 0.001). Similarly, the VAS scores were not different between groups (Pgroup = 0.667), but the scores decreased with time (Ptime < 0.001); the group×time interaction was not significant (Pinteraction = 0.274). At the 12-month mark following the operation, in the artificial dermis group, the MCRR score was S3+ in 23 patients, while it ranged from S0 to S3 in two patients; in the control group, S3+ was observed in 17 patients, and S0-S3 in three (P = 0.815). CONCLUSION: Artificial dermis treatment is considered a safe and effective alternative therapy for patients with skin and soft tissue defects accompanied by bone or tendon exposure who cannot tolerate or are unwilling to undergo autologous skin flap transplantation. It offers the advantages of minimal donor site trauma, simplicity in operation, and favorable postoperative functional recovery.

Lymphoma Mimicking Pyoderma Gangrenosum: A Case Report.

Some inflammatory conditions, such as pyoderma gangrenosum, and tumoral conditions, such as lymphoma, may appear as soft tissue infections. Herein, a cutaneous lymphoma patient who was hospitalized with a diagnosis of soft tissue infection and was considered to have pyoderma gangrenosum during follow-up is presented. Immediate histopathological examination should be recommended to diagnose skin soft tissue lesions, especially long-term and unresponsive to treatment.

Clinical characteristics and outcomes of adult alveolar rhabdomyosarcoma patients on first-line systemic therapies: A single-institution cohort.

Background: Rhabdomyosarcomas are the most common soft tissue sarcoma in children, and pediatric alveolar rhabdomyosarcoma (ARMS) prognosis has improved based on cooperative studies. However, in adults, ARMS is significantly rarer, has poorer outcomes, and currently lacks optimal treatment strategies. Objective: This study aimed to evaluate the clinical outcome of an adult ARMS population with different front-line systemic chemotherapies and determine if any chemotherapy regimen is associated with improved survival. Materials and methods: This is a retrospective study of histologically confirmed fusion-positive ARMS patients over 18 years of age, who were treated at MD Anderson Cancer Center (MDACC) from 2004 to 2021 and received systemic chemotherapy. Descriptive clinical statistics were performed, including staging, front-line chemotherapy, multimodal therapy usage, response rates, and survival analyses. Results: 49 ARMS patients who received upfront chemotherapy were identified. Locoregional treatments included radiotherapy (RT) alone (29%, n = 14), surgery alone (10%, n = 5), or both (45%, n = 22). Median overall survival (OS) for the entire cohort was 3.6 years, and the overall response rate to systemic therapy was 89%. No chemotherapy regimen showed OS benefit, specifically analyzing the pediatric-based vincristine, actinomycin-D, cyclophosphamide (VAC) or adult-based vincristine, doxorubicin, ifosfamide (VDI) regimens, even when controlled for other clinical risk factors. Conclusion: In this single-center contemporary series, adult ARMS patient outcomes remain poor. There was no statistically significant OS difference in patients who did or did not receive adult or pediatric based ARMS regimens, although a high overall response rate to chemotherapy was seen across the entire cohort. Based on these observations, further randomized prospective studies are necessary to delineate which frontline chemotherapy regimen is most beneficial in this rare adult cancer.

Soft tissue aneurysmal bone cyst presenting as an enlarging neck mass: Case report and review of the head and neck literature.

Soft tissue aneurysmal bone cysts (STABCs) are rare neoplasms histopathologically identical to aneurysmal bone cysts. These benign lesions are characterized by thin, peripheral ossification and no skeletal continuity. STABC may be difficult to distinguish from myositis ossificans (MO) and malignant entities from imaging and fine needle aspiration, due to rarity and overlapping features. We present a case of a STABC occurring in the paraspinal cervical muscles. The imaging, histopathology, molecular analysis, and treatment are discussed. Four other published cases of STABC of the head and neck are reviewed.

Oral focal mucinosis: A systematic review.

Oral focal mucinosis (OFM) is a rare lesion first described in 1974, but the aetiology remains unknown. Clinically, OFM presents as an asymptomatic nodular lesion and the similarity of clinical features to other soft tissue injuries makes the diagnosis difficult. The aim of this study was to integrate the demographic, clinical, and histopathological characteristics from previously published cases of OFM into a systematic review. Electronic searches without publication date restriction were performed in the following databases: Embase, PubMed, Medline, Web of Science, and Scopus. Case reports or case series of OFM published in English and presenting enough clinical and histopathological information were included. This systematic review identified 42 studies from 12 countries, comprising 113 cases of OFM. This lesion affected more females than males, usually in the fourth decade of life. The gingiva was the most common anatomical location, followed by the palate. Clinical presentation was most often an asymptomatic nodule. Imaging exams revealed that most cases did not have bone involvement. Surgical removal was the treatment of choice for most cases and only one recurrent case was reported. In conclusion, OFM is an uncommon pathology, and its diagnosis depends on histopathological analysis. The lesion could be included as a differential diagnosis of benign soft tissue lesions of the oral cavity, especially those affecting the gingiva.

Visco-hyperelastic material model fitting to experimental stress-strain curves using a genetic algorithm and its application to soft tissue simulants.

Ballistic impacts on human thorax without penetration can produce severe injuries or even death of the carrier. Soft tissue finite element models must capture the non-linear elasticity and strain-rate dependence to accurately estimate the dynamic human mechanical response. The objective of this work is the calibration of a visco-hyperelastic model for soft tissue simulants. Material model parameters have been calculated by fitting experimental stress-strain relations obtained from the literature using genetic algorithms. Several parametric analyses have been carried out during the definition of the optimization algorithm. In this way, we were able to study different optimization strategies to improve the convergence and accuracy of the final result. Finally, the genetic algorithm has been applied to calibrate two different soft tissue simulants: ballistic gelatin and styrene-ethylene-butylene-styrene. The algorithm is able to calculate the constants for visco-hyperelastic constitutive equations with high accuracy. Regarding synthetic stress-strain curves, a short computational time has been shown when using the semi-free strategy, leading to high precision results in stress-strain curves. The algorithm developed in this work, whose code is included as supplementary material for the reader use, can be applied to calibrate visco-hyperelastic parameters from stress-strain relations under different strain rates. The semi-free relaxation time strategy has shown to obtain more accurate results and shorter convergence times than the other strategies studied. It has been also shown that the understanding of the constitutive models and the complexity of the stress-strain objective curves is crucial for the accuracy of the method.