Anterior Head Research Articles

Comparison of [99mTc]Tc-tilmanocept with [99mTc]Tc-sulphur colloids and [99mTc]Tc-albumin colloids for sentinel lymph node detection in patients with cutaneous malignancies of the head

PurposeSentinel lymph node (SLN) biopsy is a staging procedure in the management of cutaneous malignancies of the head. The ideal radiopharmaceutical is controversial. This study aimed to compare [99mTc]Tc-tilmanocept (TcTM) with [99mTc]Tc-sulphur colloid (TcSC) and [99mTc]Tc-albumin colloid (TcAC) for SLN detection in the head and neck region.MethodsData from 62 patients with cutaneous malignancies of the head who were injected with TcTM, TcSC, or TcAC before SLN imaging (SLN-I) and SLN excision (SLN-E) between 2012 and 2021 were retrospectively analysed. SLN-I was performed using planar lymphoscintigraphy and SPECT/CT, and a gamma probe was used for SLN-E. The SLN-I localisation rate (patients with SLNs) and degree (SLN number) and SLN-E relocalisation rate (patients with SLNs) and ratio (SLN number in SLN-E/SLN number in SLN-I) were compared between TcTM, TcSC, and TcAC.ResultsTcTM showed similar SLN-I localisation rates for primaries in the anterior and posterior head region compared with TcSC (84.6% vs. 72.4%, p=0.680; both 100.0%) and TcAC (84.6% vs. 75.0%, p=1.000; both 100.0%). The SLN-I localisation degree for TcTM was higher for primaries in the anterior head region and similar for primaries in the posterior head region compared with TcSC (3.2 vs. 2.3, p=0.034; and 1.8 vs. 2.2, p=0.506) and TcAC (3.2 vs. 2.0, p=0.038; and 1.8 vs. 2.7, p=0.329). The SLN-E relocalisation rates and ratios were similar for all.ConclusionOn the basis of a limited study design that compared three different tracers in three different patient groups, TcTM showed comparable overall performance to TcSC and TcAC.

How much force is acting on the shoulder joint to create a Hill-Sachs Lesion or reverse Hill-Sachs Lesion?

BackgroundIt has not been clarified yet how much force is acting on the shoulder joint to create Hill-Sachs/reverse Hill-Sachs lesions which are commonly observed in patients with anterior or posterior shoulder instability. The purpose of this study was to determine the magnitude of force to create these bony lesions using cadaveric shoulders. MethodsFourteen fresh-frozen cadaveric shoulders were used. Compression tests were performed using the universal testing machine. The specimens were randomly divided into two groups. In group A, the posterior humeral head (the bare area and articular cartilage) was first compressed against the anterior glenoid rim to simulate a Hill-Sachs lesion, followed by the anterior humeral head being compressed against the posterior glenoid rim. In group B, the same procedure was repeated in the reverse order. X-ray microcomputed tomography (microCT) was also performed. ResultsThe maximum compression force to create a Hill-Sachs lesion was 771 ± 214 N (mean ± SD) on the articular cartilage of the posterior humeral head, which was significantly greater than the force of 447 ± 215 N to create it on the bare area (P = 0.0086). Regarding the reverse Hill-Sachs lesions, the maximum compression force was 840 ± 198 N when it was created on the articular cartilage of the anterior humeral head, which was significantly greater than the force of 471 ± 100 N when it was created at the footprint of the subscapularis tendon (P = 0.0238). MicroCT showed multiple breakage of the trabecular bone. ConclusionA force to create a Hill-Sachs lesion or a reverse Hill-Sachs lesion was significantly greater when it was created on the humeral articular cartilage than at the non-cartilage area. Also, the force to create a reverse Hill-Sachs lesion was significantly greater than the one to create a Hill-Sachs lesion.

Right Arm Pain—Football

HISTORY: A 16-year-old right-hand dominant male football lineman presents for acute on chronic R anterior shoulder pain. 7 days prior to presentation he hit a blocking dummy and felt his R shoulder “pop in and out” and subsequently had a “dead arm”. Today his R shoulder feels stiff and aches with overhead activities. He has rested since the injury. No neck pain or numbness/tingling. He previously had episodes of feeling his shoulder shift out of place, none of which required formal reduction. PHYSICAL EXAMINATION: Musculoskeletal: R shoulder.Inspection: R biceps appears smaller than L; no deformity. Palpation: nonspecific tenderness over anterior shoulder. ROM: full FLEX/EXT/ABD/ER/IR; slight pain with ER and ABD. Strength: 5-/5 biceps; 5-/5 shoulder FLEX; all rotator cuff muscles are strong. Special Tests: O’Brien’s test +; apprehension/relocation test +; posterior load and shift causes pain. Neurovascular: sensation intact in all UE dermatomes; radial artery pulses 2+. Neck exam: no midline tenderness; full ROM. DIFFERENTIAL DIAGNOSIS: glenoid labral tear; glenohumeral dislocation and subsequent instability; long head biceps tendon (LHBT) dislocation; congenital absence or anomalous origin of LHBT. TEST AND RESULTS: MR shoulder arthrogram: anterior and posterior humeral head impaction fractures consistent with recent anterior and posterior shoulder dislocation; anterior and posterior labral tears; absence of long head of biceps. Diagnostic US of the R shoulder was performed after MRI reported absent LHBT. US revealed medial dislocation of the long head of the biceps located directly lateral to the coracoid process and passing over the lesser tuberosity. The bicipital groove is shallow and without overlying tendon. FINAL WORKING DIAGNOSIS: dislocation of long head of biceps; anterior and posterior glenoid labrum tear; Hill-Sachs and reverse Hill-Sachs lesion. TREATMENT AND OUTCOMES: The patient was referred to orthopedic surgery and subsequently scheduled for R shoulder arthroscopy with labral repair/capsulorrhaphy. LHBT will be evaluated and tenotomy or tenodesis will be performed depending on operative findings. The planned surgery is scheduled for after the date of abstract submission, and final treatment and outcome will be updated.

Larval Gnathostoma: morphological identification and probable source of a case of human eye infection in Assam, India

The present communication deals with morphological identification of a parasite specimen sent from a private eye hospital at Guwahati, Assam after its extraction alive from the aqueous humor in the right eye of a non-tribal rural woman from Assam. The parasite 3 mm X 0.3 mm in size, characterized by the presence of a distinct anterior head bulb armed with four rows of hooklets numbering less than 40 per row and spination along the transverse striations present throughout the body was identified as the third stage larva of a pig gnathostome, Gnathostoma doloresi. Interview based investigation to ascertain the source of G. doloresi infection reported here for the first time in the 32 year old non-vegetarian house wife having no history of raw fish consumption revealed water used for domestic purpose from a pond adjacent to domestic pig pastured swampy area and the fresh water fishes as the possible sources of infection which might have occurred by accidental ingestion of infected cyclops present in pond water or by direct skin penetration of the larval stage of the parasite during descaling and evisceration of infected fishes prepared for cooking and consumption.

Cd248a and Cd248b in zebrafish participate in innate immune responses.

CD248, also known as endosialin or tumor endothelial marker 1, is a type I single transmembrane glycoprotein. CD248 has been demonstrated to be upregulated in cancers, tumors and many fibrotic diseases in human and mice, such as liver damage, pulmonary fibrosis, renal fibrosis, arthritis and tumor neovascularization. However, no definite CD248 orthologs in fish have been documented so far. In this study, we report the identification of cd248a and cd248b in the zebrafish. Both the phylogenetic analysis and the conserved synteny strongly suggested that zebrafish cd248a and cd248b are orthologs of the human CD248. Both cd248a and cd248b exhibited similar and dynamic expression pattern in early development, both genes had weak maternal expression, the zygotic transcripts were first seen in anterior somites and head mesenchyme, then shifted to eyes and head mesenchyme, later expanded to branchial arches, and gradually declined with development. The expression profiles of cd248a and cd248b were upregulated upon LPS (Lipopolysaccharide) challenge. Both Cd248a protein and Cd248b protein were localized on the cell membrane and cytoplasm, and overexpression of cd248a and cd248b induced the expression of pro-inflammatory cytokines, in vitro and in vivo. Moreover, deficiency of cd248a or cd248b both downregulated the expression of pro-inflammatory cytokines and upregulated anti-inflammatory cytokine. Additionally, loss of cd248a or cd248b both downregulated the expression of pro-inflammatory cytokines after LPS treatment. Taken together, these results indicated that cd248a and cd248b in zebrafish were involved in immune response and would provide further information to understand functions of Cd248 protein in innate immunity of fish.

Paper 72: How Much Glenoid Bone Loss Needs to be Restored with a Latarjet?

Objectives:Significant anterior glenoid bone loss in the setting of recurrent instability may warrant a coracoid transfer (Latarjet). However, the amount of glenoid width that must be restored with a Latarjet in order to reestablish glenohumeral stability has not been studied.We hypothesize that restoration of greater than 90% of glenoid width with a Latarjet will be necessary to restore glenohumeral stability. We also hypothesize that there will be significant increases in anterior humeral head translation when 90% or less of the native glenoid width is restored and that contact pressures on the coracoid graft will increase.Methods:Seven cadaveric specimens were prepared and mounted on an established shoulder simulator, which loads shoulder tendons through a system of pulleys and weights. A motion tracking system to record glenohumeral translations was placed on the scapula and humerus and registered based on a computed tomography (CT) scan. Contact pressures were mapped and recorded using a TekScan secured to the glenoid face and coracoid graft transfer (Figure 1). The humerus was placed in 90 degrees of humerothoracic abduction.Coracoid osteotomy was performed, and the coracoid graft was sized to a depth of 10mm. A lesser tuberosity osteotomy (LTO) was performed to allow accurate removal of glenoid bone. The amount of bone loss needed to re-establish 110%, 100%, 90% and 80% of native glenoid width after Latarjet was calculated by directly measuring the widest point of the glenoid and confirming accuracy based on the CT scan. Glenoid bone loss was established using a burr and the coracoid graft transfer was secured to the anteroinferior glenoid with two screws. The conjoined tendon was passed through a subscapularis split and the LTO was repaired with multiple Kirshner wires prior to each testing condition (Figure 2). Additionally, the rotator interval was closed and the capsule was repaired prior to each testing condition.The supraspinatus, subscapularis, infraspinatus and conjoined tendons were each loaded with 22N. Testing conditions included native glenohumeral joint, LTO, Bankart tear, and then 110%, 100%, 90% and 80% of glenoid width restoration with Latarjet. Glenohumeral translations and contact pressures were recorded with an anteroinferior load of 0 or 44N at 0 degrees of glenohumeral external rotation.Results:Progressive increases in anterior humeral head translation occurred with an anteroinferior load as the amount of glenoid width restored decreased (Figure 3). An anteroinferior load created an average of 5.5mm, 9.6mm, 3.3mm, 3.6mm, 9.2mm and 10.2mm of anterior translation in the LTO, Bankart, 110%, 100%, 90% and 80% of glenoid restoration cohorts, respectively. Greater glenoid bone loss also led to more contact pressure on the coracoid graft after Latarjet (Figure 4). An anteroinferior load produced 26.4%, 46.9%, 86.2% and 94.4% of the contact pressures on the coracoid graft relative to the native glenoid with glenoid width restored to 110%, 100%, 90% and 80%, respectively.Conclusions:There is an increase in anterior humeral head translation and contact pressure on the coracoid graft when 90% or less of the native glenoid width is restored with Latarjet. By determining the goals for glenoid width restoration after Latarjet, the findings of this study may provide guidance for patient-specific size requirements for the coracoid based on preoperative imaging. When greater than 90% of glenoid width cannot be restored with a Latarjet, surgeons may consider alternative graft sources.

Ultrasound Assessment of Anterior Humeral Head Translation in Patients With Anterior Shoulder Instability: Correlation With Demographic, Radiographic, and Clinical Data.

Background:Ultrasonography can be used to quantitatively assess anterior humeral head translation (AHHT) at different degrees of shoulder abduction. Risk factors for recurrent shoulder instability have been identified.Hypothesis:It was hypothesized that the number of dislocations or glenoid or humeral bone loss would be associated with more AHHT as measured using ultrasound.Study Design:Cross-sectional study; Level of evidence, 3.Methods:A total of 39 patients who underwent surgery for anterior shoulder instability were prospectively studied. Ultrasound assessment of AHHT was performed immediately after general anesthesia was induced. The upper arm was placed at 0°, 45°, and 90° of abduction, and a 40-N anterior force was applied to the proximal third of the arm. The distance from the posterior edge of the glenoid to that of the humeral head was measured at each abduction angle using ultrasound with and without a 40-N anterior force, and the AHHT was calculated. The differences in translation at each shoulder angle were compared. Additionally, the authors investigated the association between AHHT and demographic, radiographic, and clinical data.Results:Compared with the AHHT at 0° of abduction (5.29 mm), translation was significantly larger at 45° of abduction (8.90 mm; P < .01) and 90° of abduction (9.46 mm; P < .01). The mean translation was significantly larger in female patients than in male patients at all degrees of abduction (P ≤ .036 for all). There was no correlation between AHHT at any abduction angle and number of dislocations, clinical data, or radiographic data (including bone loss).Conclusion:Ultrasound assessment of AHHT showed larger amounts of laxity at 45° and 90° than at 0° of abduction. Anterior glenohumeral laxity was greater in female than male patients. Glenoid or humeral bone loss did not correlate with AHHT, thereby clarifying that bone loss has no direct effect on measurements of capsular laxity in neutral rotation.

Forward Head Posture in Young Adults: A Systematic Review

A recent study shows that almost 78% of population have its neck in working position within 24 hours causing continuous stress on neck and shoulders which is forcing the neck in anterior or forward head posture. This may lead to upper back tightness and muscle spasm causing nagging to sharp pain. Hence, cervical pain and neck pain getting more attention. This study is designed to narratively review the prevalence of forward head posture in young adults Methods: A structured search on literature was done through various electronic and print data bases such as: Pubmed, cinhal, google scholar, science direct, cochrane library and scopus. Those studies were included in which age ranged from 20 to 45 years. Young adults from any profession were included. Those studies were excluded in which forward head posture was reported due to any systemic issue Results: A total of 120 studies had gone through in which 65 studies were short listed and on further review only 4 studies were included as they fit in proper methodology and hence, reviewed and reported. Studies reported a considerable variation in the prevalence with the clear greater incidence Conclusions: Forward head posture is a commonly seen disorder among young adults. Investigations and interventions in time along with knowledge of postural correction can deal with this raising problem.

Immune Modulation Ability of Hepcidin from Teleost Fish.

Simple SummaryAntimicrobial peptides are part of the fish defense system, which can directly eliminate pathogenic microorganisms and, at the same time, regulate the immune response against them. This study evaluated the immunomodulatory effects of the antimicrobial peptide hepcidin in both juvenile fish and fish leukocyte cells. The results showed that hepcidin increased the expression of TNF-α, IL-1β, and IL-10 cytokines in leukocyte cells from trout. Moreover, the mRNA expressions of the same cytokines were up-regulated in different immune tissue of sea bass, confirming in vitro results. This study provides new insights into immunomodulatory function complementary to hepcidin’s previously established antimicrobial activity modulating the pro- and anti-inflammatory responses in teleost fish.Antimicrobial peptides (AMP) play an essential role in the innate immune system, modulating the defense response. In a previous study, we demonstrated the antimicrobial activity of synthetic hepcidin (hep20) from rainbow trout (Oncorhynchus mykiss), and its protective effect in European sea bass (Dicentrarchus labrax) challenged with Vibrio anguillarum. Additionally, we described the uptake and distribution of hep20 in different tissues and leukocyte cells. Interestingly, various AMPs characterized in high vertebrates, called host defense peptides (HDPs), also possess immunomodulation activity. For that reason, the present study explores the immunomodulatory abilities of hep20 through in vitro and in vivo studies. First, a monocyte/macrophage RTS-11 cell line from rainbow trout was used to evaluate hep20 effects on pro- and anti-inflammatory cytokines in fish leukocyte cells. Next, the European sea bass juveniles were used to determine if hep20 can regulate the expression of cytokines in fish immune tissues. The results show that hep20 was uptake inner to RTS-11 cells and was able to induce the expression of IL-10, IL-1β, and TNFα at transcriptional and protein levels. Then, the European sea bass juveniles were given intraperitoneal injections of the peptide. At 1, 3, 7, 14, and 21 days post-injection (dpi), IL-10, IL -1β, and TNFα mRNA were quantified in the anterior gut, spleen, and head kidney. The hep20 was able to up-regulate cytokine gene expression in these tissues, mainly in the head kidney. Furthermore, the evaluated cytokines showed a cyclical tendency of higher to lesser expression. Finally, a bioinformatics analysis showed that the structure adopted by hep20 is similar to the γ-core domain described for cysteine-stabilized AMP, defined as immunomodulatory and antimicrobial, which could explain the ability of hep20 to regulate the cytokine expression. This study provides new insights into immunomodulatory function complementary to the previously established antimicrobial activity of hep20, suggesting a role as an HDP in teleost fish. These facts are likely to be associated with molecular functions underpinning the protective effect of fish hepcidin against pathogens.

The anterior head of deltoid in relation to anterior clavicle plating: how much are we releasing?

Six right and 4 left cadaver shoulders were dissected, each from separate cadaveric specimens (6 male and 4 female). All measurements were made with digital calipers. The length of the clavicle was measured from the acromioclavicular joint to the sternoclavicular joint. The length of deltoid origin on the lateral clavicle was measured from the acromioclavicular joint to the most medial attachment of the deltoid on the clavicle. Percentage of clavicle with deltoid origin was subsequently calculated. The average length of the cadaveric clavicles was 164.4 mm with a range from 134.3 to 178.1 mm. The average amount of deltoid origin on the clavicle was 58.7 mm with a range from 43.4 to 69 mm. On average 35.5% of the clavicle had deltoid origin, with a range from 30.2% to 38.8%. On average, 35.5% of the clavicular osseous anatomy contains deltoid origin. This should be taken into consideration when performing anterior plating for clavicle fractures. With a significant portion of deltoid origin elevated, surgeons may consider altering postoperative protocols until some interval healing has occurred to this anterior head of the deltoid.

Short-term effects of instrument-assisted soft tissue mobilization compared to algometry pressure release in tension-type headache: a randomized placebo-controlled trial

ABSTRACT Purposes To compare the effectiveness of instrument-assisted soft tissue mobilization (IASTM) and pressure algometry with sham ultrasound (control group) on the clinical measures of headache, pressure pain threshold (PPT) of upper trapezius and suboccipital muscles and cervical alignment in patients with tension type headache (TTH). Methods Seventy-two patients with TTH of both genders were randomly allocated to 3 experimental groups: a) the IASTM group (n=24), b) pressure algometry group (n=24), and c) sham ultrasound control group (n=24). Headache frequency and disability, pressure pain threshold of upper trapezius and suboccipital muscles, cervical lordosis angle (CA) and anterior head translation (AHT) were measured four weeks before and after intervention. Moreover, headache frequency was followed up for two more weeks after intervention. Results Statistically significant improvements (P <0.05; effect size ranges 1.1-1.9) were observed in all outcome measures following IASTM compared to the other two intervention methods. In the IASTM group, the headache frequency decreased from 15 to 2 days/month. Also, headache disability decreased from 19 to 10. Further, CA increased from 17.5° to 31.4° and AHT decreased from 24.1 to 15.5 mm. The pressure algometry group showed significantly lower headache frequency at the follow-up (P < 0.01) than the sham ultrasound control group. However, Similar findings in the other evaluated outcomes were found between the pressure algometry and sham ultrasound control groups (P ˃ 0.05). Conclusion The results of the present study indicate the effectiveness of IASTM in improving headache symptoms and cervical alignment in patients with TTH.

The Influence of Different Rope Jumping Methods on Adolescents' Lower Limb Biomechanics during the Ground-Contact Phase.

As a simple and beneficial way of exercise, rope skipping is favored by the majority of teenagers, but incorrect rope skipping may lead to the risk of injury. In this study, 16 male adolescent subjects were tested for bounced jump skipping and alternating jump rope skipping. The kinematic data of the hip, knee, ankle and metatarsophalangeal joint of lower extremities and the kinetics data of lower extremity touching the ground during rope skipping were collected, respectively. Moreover, the electromyography (EMG) data of multiple muscles of the lower extremity were collected by Delsys wireless surface EMG tester. Results revealed that bounced jump (BJ) depicted a significantly smaller vertical ground reaction force (VGRF) than alternate jump (AJ) during the 11–82% of the ground-contact stage (p < 0.001), and the peak ground reaction force and average loading rate were significantly smaller than AJ. From the kinematic perspective, in the sagittal plane, when using BJ, the flexion angle of the hip joint was comparably larger at 12–76% of the ground-contact stage (p < 0.01) and the flexion angle of the knee joint was significantly larger at 13–72% of the ground-contact stage (p < 0.001). When using two rope skipping methods, the minimum dorsal extension angle of the metatarsophalangeal joint was more than 25°, and the maximum was even higher than 50°. In the frontal plane, when using AJ, the valgus angle of the knee joint was significantly larger during the whole ground-contact stage (p < 0.001), and the adduction angle of the metatarsophalangeal joint (MPJ) was significantly larger at 0–97% of the ground-contact stage (p = 0.001). EMG data showed that the standardized value of root mean square amplitude of the tibialis anterior and gastrocnemius lateral head of BJ was significantly higher than AJ. At the same time, that of semitendinosus and iliopsoas muscle was significantly lower. According to the above results, compared with AJ, teenagers receive less GRF and have a better landing buffer strategy to reduce load, and have less risk of injury during BJ. In addition, in BJ rope skipping, the lower limbs are more inclined to the calf muscle group force, while AJ is more inclined to the thigh muscle group force. We also found that in using two ways of rope skipping, the extreme metatarsophalangeal joint back extension angle could be a potential risk of injury for rope skipping.

Neodontobutis lani, a new sleeper fish of the family Odontobutidae (Teleostei: Gobiiformes) from Guangxi, southern China.

A new species, Neodontobutis lani (Odontobutidae) is described from the Zuojiang River, a tributary of the Xijiang River of the Pearl River basin, at Longzhou Town, Guangxi Zhuang Autonomous Region, Southern China. This species can be distinguished from other Neodontobutis species by following characters: anterior head flat, with interorbital width / eye diameter = 1.41.9 (vs. less than 1.4); several rows (vs. single row) of transforming ctenii on posterior edges of body scales; sensory papilla on lower jaw arranged in two oblong clusters (vs. two single lines). It can be distinguished from Odontobutis species by: separated right and left gill membrane (vs. joined); barbel-like projection present on sensory papillae. Molecular phylogenetic analysis of 2,076 nuclear coding loci indicates that N. lani is a sister species of N. hainanensis, the only Neodontobutis species that has been described from China.

How body patterning might have worked in the evolution of arthropods-Acase study of the mystacocarid Derocheilocaris remanei (Crustacea, Oligostraca).

Body organization within arthropods is enormously diverse, but a fusion of segments into "functional groups" (tagmatization) is found in all species. Within Tetraconata/Pancrustacea, an anterior head, a locomotory thorax region, and a posterior, mostly limbless tagma known as the abdomen is present. The posterior-most tagma in crustaceans is frequently confused with the malacostracan, for example,decapod pleon often misleadingly termed abdomen, however, its evolutionary and developmental origin continues to pose a riddle, especially the completely limbless abdomen of the "entomostracan morphotype" (e.g., fairy shrimps). Since the discovery of Hox genes and their involvement in specifying the morphology or identity of segments, tagmata, or regions along the anteroposterior axis of an organism, only a few studies have focused on model organisms representing the "entomostracan morphotype" and used a variety of dedicated Hox genes and their transcription products to shine light on abdomen formation. The homeotic genes or the molecular processes that determine the identity of the entomostracan abdomen remain unknown to date.This study focuses on the "entomostracan morphotype" representative Derocheilocaris remanei (Mystacocarida). We present a complete overview of development throughout larval stages and investigate homeotic gene expression data using the antibody FP6.87 that binds specifically to epitopes of Ultrabithorax/Abdominal-A proteins.Our results suggest that the abdomen in Mystacocarida is bipartite (abdomen I + abdomen II). We suggest that the limbless abdomen is an evolutionary novelty that evolved several times independently within crustaceans and which might be the result of a progressive reduction of former thoracic segments into abdominal segments.

A Study Comparing Gait and Lower Limb Muscle Activity During Aquatic Treadmill Running with Different Water Depth and Land Treadmill Running.

Aquatic treadmill running is a partial weight-bearing exercise for rehabilitation. The purpose of this study was to investigate the surface electromyography activities of the rectus femoris, tibialis anterior, biceps femoris and medial head of gastrocnemius, and gait kinematics during aquatic treadmill running in water levels at waist, mid-thigh and mid-shin and on land. Seventeen healthy subjects (9 males and 8 females) were recruited by convenience sampling. Participants performed 2-min aquatic treadmill running at a specific speed for each water depth. The test speed was selected based upon the speed that elicited 110 steps per min. The surface electromyography data of lower limb muscles and the joint angles at three different water depths and on land were collected to evaluate the muscle activity and gait kinematics using a waterproofed surface electromyography system and inertial measurement unit for each muscle. Results showed that rectus femoris electromyography was different between depths during the swing and stance phases. Likewise, biceps femoris and tibialis anterior electromyography were different between depths for the swing phase. However, it was not the case for gastrocnemius electromyography. Peak flexion angles in both left and right hips were different between depths. A significant increase in a stance/swing ratio was observed with rising water depths. Water depth influenced muscle activity as well as kinematics. Aquatic treadmill running in the mid-thigh level should be further evaluated for its effectiveness, training value and applicability.

Predicting Collapse in Osteonecrosis of the Femoral Head Using a New Method: Preserved Angles of Anterior and Lateral Femoral Head.

Femoral head collapse (FHC) is associated with a poor prognosis in osteonecrosis of the femoral head (ONFH). Preserved angles (PAs), including the lateral preserved angle (LPA), the anterior preserved angle (APA) and the combined preserved angle (CPA), can be used to quantify the extent of femoral head necrosis and predict the risk of femoral head collapse. The purpose of this retrospective cohort study was to assess the efficacy of these preserved angles in the prediction of femoral head collapse using plain radiographs. Patients with ONFH treated conservatively between January 2010 and January 2019 were analyzed retrospectively to assess the risk of FHC. A logistic regression model was used to evaluate the independent prognostic factors associated with FHC, including age, sex, etiology, onset of symptom, The Japanese Investigation Committee classification, and PAs (LPA, APA, and CPA). A total of 137 patients, with 180 hips, had follow-up of at least two years and were included. During the follow-up period, FHC occurred in 89 hips (49.44%) after the initial diagnosis. Multivariable analysis indicated that CPA (odds ratio [OR] = 0.95; 95%CI = 0.93-0.97; P < 0.01) was a stronger predictor of femoral head collapse compared with the Japanese Investigation Committee classification (OR = 2.40, 95%CI = 0.92-6.25; P > 0.01). The receiver operating characteristic and survival curve analyses revealed that the predictive cutoff point for the CPA was 118.7° (sensitivity = 96.70%, specificity = 79.78%, log-rank test: P < 0.01). Assessment of preserved angles on plain radiographs is a simple method to quantify the extent of lateral and anterior necrosis of the femoral head. Specifically, CPA has a potential value in predicting femoral head collapse.

Reduced Retinoic Acid Signaling During Gastrulation Induces Developmental Microcephaly.

Retinoic acid (RA) is a central signaling molecule regulating multiple developmental decisions during embryogenesis. Excess RA induces head malformations, primarily by expansion of posterior brain structures at the expense of anterior head regions, i.e., hindbrain expansion. Despite this extensively studied RA teratogenic effect, a number of syndromes exhibiting microcephaly, such as DiGeorge, Vitamin A Deficiency, Fetal Alcohol Syndrome, and others, have been attributed to reduced RA signaling. This causative link suggests a requirement for RA signaling during normal head development in all these syndromes. To characterize this novel RA function, we studied the involvement of RA in the early events leading to head formation in Xenopus embryos. This effect was mapped to the earliest RA biosynthesis in the embryo within the gastrula Spemann-Mangold organizer. Head malformations were observed when reduced RA signaling was induced in the endogenous Spemann-Mangold organizer and in the ectopic organizer of twinned embryos. Two embryonic retinaldehyde dehydrogenases, ALDH1A2 (RALDH2) and ALDH1A3 (RALDH3) are initially expressed in the organizer and subsequently mark the trunk and the migrating leading edge mesendoderm, respectively. Gene-specific knockdowns and CRISPR/Cas9 targeting show that RALDH3 is a key enzyme involved in RA production required for head formation. These observations indicate that in addition to the teratogenic effect of excess RA on head development, RA signaling also has a positive and required regulatory role in the early formation of the head during gastrula stages. These results identify a novel RA activity that concurs with its proposed reduction in syndromes exhibiting microcephaly.

Loss of Foxd4 Impacts Neurulation and Cranial Neural Crest Specification During Early Head Development.

The specification of anterior head tissue in the late gastrulation mouse embryo relies on signaling cues from the visceral endoderm and anterior mesendoderm (AME). Genetic loss-of-function studies have pinpointed a critical requirement of LIM homeobox 1 (LHX1) transcription factor in these tissues for the formation of the embryonic head. Transcriptome analysis of embryos with gain-of-function LHX1 activity identified the forkhead box gene, Foxd4, as one downstream target of LHX1 in late-gastrulation E7.75 embryos. Our analysis of single-cell RNA-seq data show Foxd4 is co-expressed with Lhx1 and Foxa2 in the anterior midline tissue of E7.75 mouse embryos, and in the anterior neuroectoderm (ANE) at E8.25 alongside head organizer genes Otx2 and Hesx1. To study the role of Foxd4 during early development we used CRISPR-Cas9 gene editing in mouse embryonic stem cells (mESCs) to generate bi-allelic frameshift mutations in the coding sequence of Foxd4. In an in vitro model of the anterior neural tissues derived from Foxd4-loss of function (LOF) mESCs and extraembryonic endoderm cells, expression of head organizer genes as well as Zic1 and Zic2 was reduced, pointing to a need for FOXD4 in regulating early neuroectoderm development. Mid-gestation mouse chimeras harbouring Foxd4-LOF mESCs displayed craniofacial malformations and neural tube closure defects. Furthermore, our in vitro data showed a loss of FOXD4 impacts the expression of cranial neural crest markers Twist1 and Sox9. Our findings have demonstrated that FOXD4 is essential in the AME and later in the ANE for rostral neural tube closure and neural crest specification during head development.

Biomechanical engineering analysis of an acute papillary muscle rupture disease model using an innovative 3D-printed left heart simulator.

OBJECTIVESThe severity of acute papillary muscle (PM) rupture varies according to the extent and site of the rupture. However, the haemodynamic effects of different rupture variations are still poorly understood. Using a novel ex vivo model, we sought to study acute PM rupture to improve clinical management.METHODSUsing porcine mitral valves (n = 32) mounted within an ex vivo left heart simulator, PM rupture was simulated. The mitral valve was divided into quadrants for analysis according to the PM heads. Acute PM rupture was simulated by incrementally cutting from 1/3 to the total number of chordae arising from 1 PM head of interest. Haemodynamic parameters were measured.RESULTSRupture >2/3 of the chordae from 1 given PM head or regurgitation fraction >60% led to markedly deteriorated haemodynamics. Rupture at the anterolateral PM had a stronger negative effect on haemodynamics than rupture at the posteromedial PM. Rupture occurring at the anterior head of the anterolateral PM led to more marked haemodynamic instability than rupture occurring at the other PM heads.CONCLUSIONSThe haemodynamic effects of acute PM rupture vary considerably according to the site and extent of the rupture. Rupture of ≤2/3 of chordae from 1 PM head or rupture at the posteromedial PM lead to less marked haemodynamics effects, suggesting a higher likelihood of tolerating surgery. Rupture at the anterolateral PM, specifically the anterior head, rupture of >2/3 of chordae from 1 PM head or regurgitation fraction >60% led to marked haemodynamic instability, suggesting the potential benefit from bridging strategies prior to surgery.

Arthroscopic Removal of the Polyethylene Glenoid Component After Total Shoulder Arthroplasty: A Systematic Review

To identify prior studies of arthroscopic glenoid component removal after total shoulder arthroplasty (TSA) and understand indications, techniques and patient outcomes. A search of the English language literature on arthroscopic removal of the glenoid component (ARGC) after TSA published between 2005 and 2021 was performed from MEDLINE and EMBASE databases. Articles with ARGC after TSA were identified and we recorded article characteristics as well as patient demographics and outcomes contained within the studies. A total of six publications (two case reports and four retrospective case series) detailing the outcome of ARGC performed on twenty-five shoulders were identified. The average time from index procedure to glenoid removal was 117 months and mean age at time of ARGC was 75 years. Although patient reported outcomes measures (PROMs) varied in type and reporting style, all articles reported improvements in PROMs. Twenty patients in this systematic review were evaluated for post-operative complications and the complication rate was found to be 15% (n = 3). There were 2 cases (18%) of superior migration of the humeral head relative to the glenoid and no reported cases of anterior or posterior humeral head subluxation. Two of 25 patients (8%) underwent subsequent open revision procedures. The limited number of publications in this systematic review demonstrates that ARGC after TSA can result in improvements in both pain and PROMs. This less-invasive arthroscopic technique may be an alternative to open revision for lower demand patients; however, future prospective, comparative studies are necessary to better define indications.