Neck Deformity Research Articles

Advanced Simultaneous Isolation, Culture, and Identification of Myoblasts and Fibroblasts From Sternocleidomastoid Muscle of Congenital Muscular Torticollis.

Congenital muscular torticollis (CMT) is a common pediatric disease caused by contracture of sternocleidomastoid muscle (SCM) that leads to neck stiffness and deformity. Based on the adhesion characteristics of different cells in affected SCM of CMT, myoblasts and fibroblasts can be isolated simultaneously by advanced culture conditions. Our study aimed to explore and optimize the isolation, culture, and identification of myoblasts and fibroblasts in SCM of CMT. Myoblasts and fibroblasts were separated by combined digestion with trypsin and collagenase. With this improved method, the morphology of isolated myoblasts and fibroblasts was observed under the microscope, the cell growth curve was drawn, and the purity of myoblasts and fibroblasts was determined by immunofluorescence. The method allowed to satisfactorily culture myoblasts and fibroblasts. The cells could stably grow and be passaged, provided they were at least 80% confluent. Immunofluorescence of myoblasts and fibroblasts showed high rate of positive staining, and cell count showed excellent growth state. Moreover, according to the growth curve, fibroblasts grew at a higher rate than myoblasts. The isolated myoblasts and fibroblasts have high purity, intact structure, and relatively high vitality. This method can be used to establish a cell model with myoblasts and fibroblasts, which can be applied to investigate etiology of CMT or mechanisms of drug action.

Twin boundary sliding in single crystalline Cu and Al nanowires

Twin boundary sliding (TBS) is a deformation mode that is typically observed in nanocrystalline metals and usually occurs at multiple locations in the twinned region, including twin boundaries, of a crystal in a situation in which additional deformation via twinning is limited. Unlike the well-established dislocation slip and necking deformation process that occurs in large crystals, recent theories that explain TBS are often controversial, and much remains unsettled. Herein, we develop a factor that enables the prediction of deformation pathways by quantitatively analyzing the relative tendency for the formation of partial dislocations based on the dislocation and fault energy theories. The developed factor considers the effects of static/extrinsic features, such as the stacking fault energy (SFE) as well as the crystal size and orientation, and dynamic structural states characterized by the various fault energies of a material. The factor is initially validated using a Cu crystal exhibiting low SFE for various orientations and sizes. To determine whether the proposed factor can be generically extended to crystals with high SFE, we perform micro-mechanical tensile tests and molecular dynamics simulations on Al nanowires. The developed factor produces self-consistent results even for metals exhibiting different SFE values. The observations can be used as a guideline to design nanoscale structures for load-carrying applications.

Modified Medial and Lateral Platysmaplasty.

In our previous anatomic study, the authors could pull the platysma effectively in the medial direction, lateral direction, or both the medial and lateral directions. In this paper, the authors analyzed the results of our series of modified medial and lateral platysmaplasties, in which the technique was based on Hamra's platysmaplasty, modified in light of Feldman's corset platysmaplasty and Mendelson's concepts.In medial platysmaplasty, subcutaneous dissection was performed from the mandibular border to 2 or 3 finger breadths above the xiphoid process. Lateral platysmaplasty required only peri-lobular subcutaneous dissection for exposing and anchoring the lateral border of the platysma to the preauricular platysma auricular fascia (PAF). Lateral dissection does not go beyond the occipital hairline. During dissection, the zygomatic retaining ligaments were detached and repositioned and anchored to the lateral side of the PAF using 4-0 sutures. One hundred sixty-eight patients underwent platysmaplasty (87 medial platysmaplasty, 76 lateral platysmaplasty, 3 isolated neck lift).The follow-up period ranged from 1 month to 156 months. In general, medial platysmaplasty was more efficacious than simple lateral pulling back for various conditions involving neck deformities, especially midline bands and severe submental fullness with skin laxity. The complications were 1 case of neuropraxia of the cervical branch (0.6%), 3 cases of hematoma (1.8%), 2 cases of seroma (1.2%), and 2 cases of submental depression (1.2%). All patients had temporary paresthesia around the periauricular area, but fully recovered by 6 months.Using this modified medial and lateral platysmaplasty, we obtained satisfactory results with low complications.

48,XXYY syndrome presenting with long-term infertility and newly observed neck deformities: a case report

BackgroundLong-term infertility can be attributed to many factors, with the genetic factor being the most overlooked due to its many nonspecific morphological or endocrine signs. We present a rare case of a patient with progressive testicular failure associated with 48,XXYY syndrome.Case presentationA 39-year-old Arab man presented to our fertility clinic for fertility treatment. He was diagnosed with primary infertility, which had been present for 20 years at the time of presentation. Our patient had nonspecific morphological features of an abnormally wide neck with front slouching neck posture, clinodactyly of the third finger, and had moderate hypoandrogenemic features. A semen analysis revealed azoospermia. Genetic tests for azoospermia, including sex-determining region Y (SRY) detection and chromosome Y microdeletion, revealed no deletion present on the Y chromosome. Karyotyping was used and our patient was diagnosed with 48,XXYY syndrome.ConclusionGenetic testing (karyotyping and so on) played a key role in the diagnosis of our patient with long-term primary infertility secondary to 48,XXYY syndrome, and should play a vital role in all cases of long-term infertility, especially when presentation is accompanied by endocrine, skeletal, or morphological symptoms, signifying an underlying genetic factor.

Diagnosis of Stage II Rheumatoid Arthritis through Functional Evaluation of Wrist and Hand among Adult Females

Background: Rheumatoid arthritis (RA) is a commonly prevailing disease among women. Disease progression deformities such as ulnar and radial shift of the wrist, Boutonnière, swan neck deformity and mallet finger become evident, which results in marked limitation of hand function. Patients usually lose the ability to hold, grasp and pinch thus activities of daily living are compromised. This study aimed to diagnose stage II Rheumatoid Arthritis through assessing the limitations of hand functions in adult females. Methods: A sample of 37 adult females with Stage II RA presenting to the rheumatology department of National hospital, Lahore and Combined Military Hospital, Lahore were recruited in the study. Patients with clinically diagnosed Stage II RA presenting with pain and dysfunction of the hands and wrist joints were included. Patients with any traumatic condition or any other bone disease that limits hand function were excluded from the study. The scale used for the assessment was Patient Rated Wrist/Hand Evaluation (PRWHE) with the reliability of >0.75 and validity of 0.7. Results: In a sample of adult women with a mean age of 42, 39% reported moderate pain and 61% had severe pain whereas the functional limitations was reported to be moderate in 47.3% while 52.7% had severe limitation of hand function. These results prove that there is a negative impact of hand malformations on hand function. Conclusion: The adult females with stage II Rheumatoid Arthritis had severely limited hand function. The functional limitations of hand were increased with disease progression especially in adult females.

STRUCTURALAND FUNCTIONAL CHANGES OF HEART IN DEPENDENCE OF GALLBLADDER CONDITION IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION

According to the literature data, gallbladder (GB) condition influences the course of coronary heart disease (CHD) and parameters of heart structure and function. The aim of this work was to estimate the peculiarities of heart condition in patients with CHD (acute myocardial infarction) in dependence of GB condition. We held a retrospective analysis of data of 142 patients. Results. It was revealed that in 83.7 % patients GB was changed: cholelithiasis (34.5 %), past cholecystectomy due to cholelithiasis (7.0 %), sludge and poliposis (17.6 %), bent GB body (13.4 %), neck deformations and signs of past cholecystitis (14.8 %). GB changes were accompanied by significant increase of heart rate, which was the most prominent in case of cholelithiasis, neck deformations and past cholecystitis signs. Conclusions. Pathological conditions of GB were accompanied by left ventricle dilatation, aortic distension, significant decrease of ejection fraction and systolic dysfunction, whereas after GB removal sizes of heart chambers were close to optimal values, although the systolic function did not normalize. Keywords: gallbladder, coronary heart disease, sludge, cholecystitis, heart structure.

Ductility of an ultrastrong glass-crystal nano-dual-phase alloy in sub-micron

We report an excellent tensile property of the Mg-based nano-dual-phase glass-crystal alloy in sub-micro size. It shows room temperature large ductility (>50% true strain, resulted from the localized necking deformation) with ultrahigh tensile strength (2.4 GPa), compared with 1.4 GPa strength and limited ductility of its metallic glass counterpart. To unraveling the underlying reasons, we have made transmission electron microscope (TEM) in-situ tensile investigation and molecular dynamic (MD) simulation for the materials, showing that homogenous plastic flow of nano-sized metallic glass phase activated by strain non-localization mechanism is responsible for the large ductility.

Post burn neck contracture: an algorithm for choosing the ideal surgical method of management

Background: The aim of the study is to facilitate choosing the surgical technique that will be suitable for improving both function and aesthetics of each patient through this suggested algorithm system. Any post burn neck contracture usually causes severe impairment of function and aesthetics, which causes serous psychological and social problems. That’s why it is very important to sub-categorize this type of deformity by anatomical location and cause of burn to allow choosing the ideal method of surgical management.Methods: This is a prospective study which was performed in Plastic Surgery Department, Menoufia University Hospitals over the period from March 2017 to March 2019. The study included 30 patients suffering post burn neck contracture deformities.Results: Patients were carefully examined, and the post burn neck deformities were analyzed according to age, condition of skin at the contracture site, the range of sternomastoid muscles movement at both sides of the neck and patient's general condition. Patients were given scores and categorized into 4 grades. And according to each patient's grade, the suitable surgical technique was chosen and fulfilled. 25 patients showed great satisfaction to their post operative’s outcomes and the rest were poorly satisfied.Conclusions: Application of patients with post burn neck contractures to this algorithm system will make it easy to choose the ideal method of management and gain the best surgical results possible when performing surgical correction.

Twin Boundary Sliding in Single Crystalline Cu and Al Nanowires

Twin boundary sliding (TBS) is a deformation mode that is typically observed in nanocrystalline metals and usually observed during the final deformation stage when deformation via twinning is limited. Unlike the well-established dislocation slip and necking deformation process that occurs in large crystals, recent theories that explain TBS are often controversial, and much remains unsettled. Herein, we develop a theory that enables the prediction of deformation pathways by quantitatively analyzing the relative tendency for the formation of partial dislocations based on the dislocation and fault energy theories. The developed theory considers the effects of static features, such as the stacking fault energy (SFE) as well as the crystal size and orientation, and dynamic structural states characterized by the various fault energies of a material. The theory is initially validated using a Cu crystal exhibiting low SFE for various orientations and sizes. In addition, micro-mechanical tensile tests and molecular dynamics simulations are conducted on Al nanowires to determine whether the proposed theory can be generically extended to crystals with high SFE. The developed theory produces self-consistent results even for metals exhibiting different SFE values. The observations can be used as a guideline to design nanoscale structures for load-carrying applications.

Tensile Properties and Microstructural Evolution of an Al-Bearing Ferritic Stainless Steel at Elevated Temperatures

The influence of temperature and strain rate on the hot tensile properties of 0Cr18AlSi ferritic stainless steel, a potential structural material in the ultra-supercritical generation industry, was investigated at temperatures ranging from 873 to 1123 K and strain rates of 1.7 × 10−4–1.7 × 10−2 s−1. The microstructural evolution linked to the hot deformation mechanism was characterized by electron backscatter diffraction (EBSD). At the same strain rate, the yield strength and ultimate tensile strength decrease rapidly from 873 K to 1023 K and then gradually to 1123 K. Meanwhile, both yield strength and ultimate tensile strength increase with the increase in strain rate. At high temperatures and low strain rates, the prolonged necking deformation can be observed, which determines the ductility of the steel to some extent. The maximum elongation is obtained at 1023 K for the strain rates of 1.7 × 10−3 and 1.7 × 10−2 s−1, while this temperature is postponed to 1073 K once decreasing the strain rate to 1.7 × 10−4 s−1. Dynamic recovery (DRV) and continuous dynamic recrystallization (CDRX) are found to be the main softening mechanisms during the hot tensile deformation. With the increase of temperature and the decrease of strain rate (i.e., 1123 K and 1.7 × 10−4 s−1), the sub-grain coalescence becomes the main mode of CDRX that evolved from the sub-grain rotation. The gradual decrease in strength above 1023 K is related to the limited increase of dynamic recrystallization and the sufficient DRV. The area around the new small recrystallized grains on the coarse grain boundaries provides the nucleation site for cavity, which generally results in a reduction in ductility. Constitutive analysis shows that the stress exponent and the deformation activation energy are 5.9 and 355 kJ·mol−1 respectively, indicating that the dominant deformation mechanism is the dislocations motion controlled by climb. This work makes a deeply understanding of the hot deformation behavior and its mechanism of the Al-bearing ferritic stainless steel and thus provides a basal design consideration for its extensive application.

Лечение пациента с сочетанием врожденной мышечной кривошеи и идиопатического сколиоза верхне-грудного отдела позвоночника

A clinical case of a combination of such pathologies of the musculoskeletal system as congenital muscular torticollis and idiopathic scoliosis in one patient, as well as stage surgical treatment with subsequent assessment of the results in dynamics is presented. We concluded that with timely treatment of neck deformity in early childhood, surgery on the thoracic spine could have been avoided

Вплив холецистектомії на стан серця, ліпідний метаболізм та активність запалення

Aim. Gallbladder disorders and ischemic heart disease share common etiopathogenetic factors of development and influence each other. Literature describes dependence of clinical presentation of ischemic heart disease on gallbladder condition, and improvement of heart condition after cholecystectomy. The aim of this study was to compare features of the heart condition, lipid metabolism parameters, inflammation activity, and their correlations in patients with ischemic heart disease after cholecystectomy and with different gallbladder conditions. Materials and Methods. We analyzed data of 197 patients with ischemic heart disease (namely, stable and unstable angina pectoris), which were diagnosed and treated according to the existing guidelines. These patients were divided into 6 groups: with intact gallbladder; with sludge, bile thickening, polyps, and cholesterosis; with bent gallbladder body and its deformations; with gallbladder neck deformations and signs of past cholecystitis; with cholelithiasis; and after cholecystectomy. Results and Discussion. It was revealed that cholecystectomy in chronic subtypes of ischemic heart disease was associated with minimal frequency of arrhythmias, and in acute subtypes - with maximal frequency. Structural and functional parameters of the heart were the best in patients with a history of cholecystectomy. This was reflected in the smallest sizes of the right ventricle (2.31 cm), the left atrium (3.95 cm), and the left ventricle (4.92 cm), along with the smallest thickness of the interventicular septum (1.14 cm) and the posterior wall of the left ventricle (1.11 cm). The patients with removed gallbladder were characterized by the lowest values of total cholesterol (4.41 mmol/L), triglycerides (1.37 mmol/L), cholesterol of low density lipoproteins (2.61 mmol/L) and the atherogenic index of plasma (2.77) among all the groups with different gallbladder condition. All the parameters were lower than the parameters of intact gallbladder group. Both Castellі indexes after cholecystectomy were lower than in the group with intact gallbladder. Conclusions. The patients with a history of cholecystectomy were characterized by better parameters of lipid metabolism than patients of the other groups with different gallbladder conditions. The cholecystectomy group was characterized by the lowest inflammation activity according to the band neutrophils count (1.77%), the neutrophils to lymphocytes ratio (3.01), and the total fibrinogen level (4.03 g/L). Key words: ischemic heart disease, cholecystectomy, echocardiography, gallbladder, lipidogram

Neutrophil to lymphocyte ratio in the diagnosis of viscero-visceral cardioneuropathy in patients with gallbladder disorders

Summary. Neutrophils to lymphocytes ratio (NLR) reflects the activity of systemic nonspecific inflammation and immune system answer. NLR can be influenced by the change of gallbladder condition. It’s a pity, but the diagnostic and prognostic opportunities of NLR are not properly used in routine clinical practice. The aim of this paper was to estimate the NLR value in the assessment of heart condition in the diagnostics of viscero-visceral cardioneuropathy in dependence of gallbladder condition in patients with cardiorheumatic disorders. We analyzed data of 506 inpatients with cardiorheumatic diseases, which were divided into groups according to gallbladder condition: intact gallbladder; sludge, polips and cholesterosis; various deformations of gallbladder body; gallbladder neck deformations and sonographic signs of past cholecystitis; cholelithiasis; anamnesis of cholecystectomy. It was established that NLR levels, revealed in this study, exceeded the levels of healthy people according to our previous studies (1.8±0.46) and literature data (1.65-1.86). NLR was dependent of gallbladder condition: maximal levels always accompanied pathological changes of the latter. On the background of active inflammatory phase of rheumatic diseases NLR was higher, than in case of stable and acute forms of ischemic heart disease. NLR correlations depended on gallbladder condition, and were the most numerous in case of intact gallbladder. NLR was associated with age, heart rate, acute phase inflammatory markers, parameters of endogenous intoxication, cytolysis and structural heart parameters (sizes of chambers, thicknesses of walls, ejection fraction). Ranking analysis of NLR of all included patients showed that its levels were maximal in case of cholecystitis in anamnesis and in patients after cholecystectomy. All other values can be clearly divided into 2 groups: intact gallbladder plus bent gallbladder body and, apart of it, other pathological conditions (sludge, signs of cholecystitis in anamnesis, cholelithiasis and cholecystectomy in anamnesis). Conclusions: NLR was the highest in case of active inflammatory process in hemorrhagic vasculitis (3.66) and rheumatic fever (3.24) than in the stable ischemic heart disease (2.47) and myocardial infarction (1.85), all р<0.05. Regardless of the disorder, NLR was dependent on the gallbladder condition and reached the maximal values in case of gallbladder changes. Taking into account the big amount of NLR correlations with clinical and laboratory parameters, and the results of instrumental diagnostics methods, we can say that NLR may be used in the diagnostics of viscero-visceral cardioneuropathy.

Platysmaplasty: Is it Possible to Pull the Platysma Effectively in the Medial or Lateral Direction?

The aim of this study was to investigate whether it is possible to pull the platysma effectively in the medial or lateral direction (medial platysmaplasty and lateral platysmaplasty) and to explore the anatomical basis of those findings.Six hemifaces from 3 fresh cadavers were dissected. After skin removal, the platysma was pulled upward and in the medial or lateral direction with the ulnar side of the palm. Its mobility was checked. In 2 volunteers, using wooden bar, the skin overlying platysma was pulled in superomedial and superolateral direction.The platysma ran diagonally from the acromio-deltoid region to the perioral and submental area. In all hemifaces, the platysma was attached to the mandible along its course. The platysma inserted into the mandibular body. At its medial portion (approximately halfway medially from the mentum to the angle; 4-5 cm), the attachment was so firm that it could not be moved horizontally. The posterolateral portion of the platysma was indirectly attached to the mandible and movable. In cadaver, platysma did not move much when it was pulled in the medial direction. In the lateral direction, however, platysma did move well. In living body, when skin overlying platysma was pulled in superomedial direction and superolateral direction, 3 points marked on mandibular border moved about 1.5-2.0 cm and 2.0-2.5 cm respectively.It is thought that medial platysmaplasty can correct anterior neck deformities and redistribute neck skin mainly in the submental area, while that lateral platysmaplasty can pull the cheek skin in superolateral direction.

Endogenous Intoxication in Patients with Coronary Heart Disease on the Background of Different Gallbladder Condition

The endogenous intoxication syndrome (EIS) is one of the leading syndromes of many pathological processes. EIS is a result of the accumulation of harmful substances. This accumulation depends on formation and excretion of bile, and gallbladder (GB) condition, because intrahepatic and intraductal bile stasis, provoked by cholelithiasis, strictures and deformations of bile ducts, cellular and enzymatic dysfunctions, worsens the detoxifying function of bile system. Together with this, persistent inflammation increases the amount of proinflammatory mediators.The objective: was to estimate EIS activity according to hematological indexes in patients with coronary heart disease (CHD), namely, non-stable angina pectoris, with various GB condition.Material and methods. We analyzed the data of 116 patients, which were divided into groups according to GB condition: intact GB; sludge, cholesterosis and GB polyps; GB body deformations; GB neck deformations and cholecystitis in anamnesis; cholelithiasis; cholecystectomy in anamnesis. According to blood analysis, we counted the cellular indexes of EIS: index of neutrophils’ reactive answer, leucocytic index of intoxication in modification of B.A. Reys, hematologic index of intoxication, intoxication marker. Results were processed by variation statistics methods. Data were considered significant if р<0,05.Results. Groups with different GB conditions were significantly different according to absolute levels of index of neutrophils’ reactive answer and both leucocytic indexes of intoxication. GB neck deformations, cholecystitis and cholelithiasis (both at the moment or in anamnesis) in patients with CHD were accompanied by activation of EIS. This tendency continued after cholecystectomy.Conclusion. Hematologic markers of intoxication directly correlated with biochemical parameters of inflammation, intoxication, lipid metabolism, and cytolysis. Increase of the former was associated with distension of mitral and aortic valves, and systolic dysfunction. In case of minimal EIS its markers did not correlate with inflammatory parameters. The biggest amount of correlations was revealed in case of present of past cholecystitis.

Effect of axial flap of adjacent artery perforator with vascular pedicle in repairing facial and cervical scar deformity in patients

Objective: To explore the effect of axial flap of adjacent artery perforator with vascular pedicle in repairing scar deformity of face and neck in patients. Methods: From January 2010 to June 2018, 38 patients with cicatricial deformity of face and neck after deep burn were admitted to author's unit, including 22 males and 16 females, aged 5-56 years. The time of admission was 7 months to 19 years after burn injury. The size of wounds ranged from 7.0 cm×4.0 cm to 20.0 cm×10.0 cm after scar tissue was released. Nineteen patients were treated by upper thoracic internal artery perforator flap with size ranged from 7.0 cm×5.0 cm to 18.0 cm×8.5 cm. Among them, 16 cases were preexpanded with expanders at thorax whose rated capacity ranged from 300 to 500 mL and times of water injection of 1.8 to 3.1, and 3 cases were directly used. Twelve patients were treated by transverse carotid artery perforator flap with size ranging from 7.0 cm×4.5 cm to 11.0 cm×8.5 cm, of which 8 patients were preexpanded and 4 cases were directly used. The rated capacity of expander placed at the supraclavicular region ranged from 200 to 350 mL with times of water injection from 1.5 to 2.0. Seven patients were treated by preexpanded superficial temporal frontal branch artery perforator flap with size of 5.5 cm×3.8 cm to 8.0 cm×5.0 cm. The rated capacity of expanders placed at forehead was 150 to 300 mL with times of water injection of 1.5 to 2.0. Donor sites were directly sutured or reversely repaired by pedicled skin tube plasty. After operation, operation times and treatment time were recorded. The survival condition and complications of flaps and follow-up were observed. Results: The patients each received 1 to 4 operation (s) with treatment time of 5 to 11 months. All flaps survived after operation. Among them, three flaps with perforating branches of internal thoracic artery had slight blood circulation disturbance at the distal end and were healed after conservative dressing change, etc. Pigment changes were observed at the distal end of thoracic internal artery perforator flaps in two patients in the later stage and was resected and repaired in the second stage. The patients were followed up for 5 to 18 months. The appearance and function of operation area were good with high satisfaction of patient. Conclusions: The axial flap of adjacent artery perforator with vascular pedicle for repairing scar deformity of face and neck used directly or preexpanded can solve the problem of lack of normal skin around scar deformity without vascular anastomosis during the operation and with better appearance and function after operation. The donor site often can be directly sutured, but many operations often need to be completed for finishing whole treatment.

Assessment of the talar deformity and alignment in congenital clubfoot using three-dimensional MRI after Ponseti method

BackgroundPonseti method have been widely accepted as the initial treatment of congenital idiopathic clubfoot because its excellent primary result. On the other hand, relapses after Ponseti method are not uncommon and the cause of relapses have not been fully elucidated. We investigated detailed morphology and alignment of tarsal bones in clubfoot after Ponseti method using three-dimensional MRI analysis. MethodsWe performed MRI with 10 patients of unilateral clubfoot at three months after Achilles tenotomy. Based on the MRI volume data, we reconstructed three-dimensional bone surface model using the marching cubes method. We evaluated the volume of the talus and navicular bone, medial and planter deviation of the talar head and neck, medial deviation of the navicular bone, and internal rotation angle of the distal tibiofibular joint. ResultsIn clubfoot, the volume of talus and navicular bone were significantly smaller compared with the contralateral side. Deviation of the talar head and neck varied from medially to almost the same as that on the contralateral side. The degree of deformity of the talus and alignment of the navicular bone and distal tibiofibular joint showed correlations. ConclusionsPatients with the medial deviated talar neck might have the alignment change of navicular bone and distal tibiofibular joint. Deformity of talar neck might to be compensated by talonavicular joint and distal tibiofibular joint through the manipulation of Ponseti method.

Coupling finite element method with large scale atomic/molecular massively parallel simulator (LAMMPS) for hierarchical multiscale simulations

In this work, we have developed a multiscale computational algorithm to couple finite element method with an open source molecular dynamics code --- the Large scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) --- to perform hierarchical multiscale simulations in highly scalable parallel computations. The algorithm was firstly verified by performing simulations of single crystal copper deformation, and a good agreement with the well-established method was confirmed. Then, we applied the multiscale method to simulate mechanical responses of a polymeric material composed of multi-million fine scale atoms inside the representative unit cells (r-cell) against uniaxial loading. It was observed that the method can successfully capture plastic deformation in the polymer at macroscale, and reproduces the double yield points typical in polymeric materials, strain localization and necking deformation after the second yield point. In addition, parallel scalability of the multiscale algorithm was examined up to around 100 thousand processors with 10 million particles, and an almost ideal strong scaling was achieved thanks to LAMMPS parallel architecture.

175. Intraoperative alignment goals for severe cervical deformity to achieve optimal improvements in health-related quality of life measures

BACKGROUND CONTEXT Patients with severe cervical deformity (CD) often have profound deficits in numerous activities of daily living. Association between health status and postoperative radiographic goals is difficult to quantify. PURPOSE Investigate the radiographic characteristics of patients who achieved optimal HRQOLs following surgery for CD. STUDY DESIGN/SETTING Retrospective review of prospective CD database. PATIENT SAMPLE Forty adult CD patients (C2-C7 Cobb>10°, CL>10°, cSVA>4cm, or CBVA>25°). OUTCOME MEASURES Health-related-quality of life (HRQL) scores, radiographic alignment. METHODS Surgical patients with severe CD were isolated based upon a previously presented combination of preop cSVA, T1 slope, maximum focal kyphosis in extension, C2 slope in extension, and number of kyphotic levels in extension. Those with available preop and 1-year postop HRQL data were included. Based on previous study, patients were grouped into 3 distinct patterns of CD: focal deformity (FD), flatneck (FN=large TS-CL and lack of compensation), or cervicothoracic (CT). Postoperative outcomes were defined as “good” if a patient had >2 of the 3 following criteria (1) NDI 2 points from baseline. Within each distinct deformity group, patients with good outcomes were compared to those with poor outcomes (ie, not meeting the criteria for good) for differences in demographics, HRQL scores, and alignment, via chi-squared or student's t-tests. RESULTS Overall, 83/153 patients met the criteria of severe CD and 40 patients had complete 1-year follow-up of clinical/radiographic data. Patient breakdown by deformity pattern was as follows: CT (N=13), FN (N=17), and FD (N=17), with 7 patients meeting criteria for both FD and FN deformities. Within the FD cohort, maximal focal kyphosis (ie, kyphosis at one level) was better corrected in patients with a “good” outcome (p = 0.03). In the FN cohort, patients who went on to have “good” outcomes presented with worse horizontal gaze (McGregor slope 21° vs 6°, p=0.061) and cSVA (72 mm vs 60 mm, p=0.030). “Good” outcome FN patients showed significantly greater postop correction of horizontal gaze (−25° vs −5°, p = 0.031). In the CT cohort, patients with “good” outcomes had superior global alignment both pre- (SVA: −17 mm vs 108 mm, p 0.050). CONCLUSIONS The results of this study highlight intraoperative goals for three distinct sagittal morphotypes of severe CD: cervicothoracic, flat neck, and focal deformity. Distinct deformity specific intraoperative goals include obtaining proper sagittal global/cervical alignment for cervicothoracic patients, correcting maximal focal kyphosis in focal deformity patients, and correcting horizontal gaze for flat neck patients. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Midterm Clinical and Radiographic Follow-Up of Pyrolytic Carbon PIP Arthroplasty

The use of pyrolytic carbon arthroplasty (PCA) for the proximal interphalangeal (PIP) joint is controversial. The goal of this study was to evaluate the clinical and radiographic midterm outcomes of PIP joint PCA. Patients were contacted after PIP PCA at 6.4 ± 1.9 years (mean ± SD). Evaluation included grip and pinch strength and digital range of motion (ROM). Radiographs and patient reported outcomes surveys were obtained. This study included 29 PIP joint PCA devices implanted in 23 hands among 19 patients. Seven devices underwent subsequent procedures. Three were removed and revised to silicone implants because of 2 dislocations and one implant migration. One underwent revision to a larger distal component. Three required soft tissue surgical revisions in which the implant was retained (one flexor digitorum superficialis tenodesis and 2 capsulectomies). At the time of latest follow-up, there was 86.2% original implant survivorship. The most recent radiographic review of the remaining 26 implants revealed 2 swan neck deformities and 2 implant migrations. Postoperative grip (38.4 ± 16.8 lb) and pinch (13.8 ± 2.7 lb) strength were 92% and 91%, respectively, of nonsurgical grip and pinch strength. Final mean ROM (range) for the metacarpophalangeal joint was 82.1° (60° to 100°) and for the PIP joint was 60.6° (20° to 110°). Mean outcome scores were: visual analog scale, 1.6 (± 2.4), Michigan Hand Questionnaire, 71.6 (± 17.6), and Disabilities of the Arm, Shoulder, and Hand, 24.7 (± 14.5). Midterm follow-up (mean, 6.4 years) for 29 PCA implants in 19 patients revealed a surgical revision rate of 24.1%. Of the 29 implants, 13.8% were removed at a mean of 4.6 years (range, 1.3-7.9 years). Strength, ROM, and pain relief were all satisfactory. Prognostic IV.