Loss Of Correction Research Articles

Impact of support instruments in medial closed-wedge distal femoral osteotomy: a finite element analysis.

Medial closed-wedge distal femoral osteotomy (MCWDFO) is a valuable treatment approach for lateral knee osteoarthritis with femoral valgus deformity. Improved results have been reported with the upgrade of surgical techniques and locking plates. However, the risk of nonunion and loss of correction increases in cases of lateral hinge fractures. This study aimed to evaluate the mechanical impact of hinge fractures and support instruments in MCWDFO using finite element analysis (FEA). Five femur models were developed using Mechanical Finder 11.0 FEA software. We simulated the following models: only a medial locking plate (MLP) (group A); an MLP with a lateral support screw (group B); and an MLP with a lateral support plate (group C). The equivalent stress around the hinge was evaluated and the percentage of the plastic deformation zone was calculated for the hinge area in the no-hinge fracture model. The equivalent stress of the MLP and the degree of displacement were calculated using the hinge fracture model. The percentages of the plastic deformation zone in groups A, B, and C were 18.0 ± 11.7%, 3.3 ± 2.4%, and 2.3 ± 2.8%, respectively. The percentages tended to be lower in groups B and C than in group A. In the hinge fracture model, the mean equivalent stress of the MLP in group C was significantly less than that in group A. In terms of the mean degree of displacement, group A showed more than 1mm of displacement, which was significantly larger than that of the other groups. The support instruments provided stability to the hinge site and reduced the equivalent stress of the main plate in the MCWDFO with hinge fractures. No significant difference was observed between the two instruments in terms of stability.

Analysis of the factors affecting the loss of correction effect in patients with congenital scoliosis after one stage posterior hemivertebrae resection and orthosis fusion

BackgroundTo analyze the factors affecting the loss of correction effect in patients with congenital scoliosis after one stage posterior hemivertebra resection, orthosis, fusion and internal fixation.MethodsThirty-nine patients with congenital scoliosis (CS) who underwent one-stage posterior hemivertebra resection, orthosis, fusion and internal fixation were retrospectively included in Hebei Children’s Hospital General demographic information of patients was collected. Preoperative and postoperative imaging indicators were compared, Including cobb Angle of the main curvature of the spine, segmental Cobb Angle, compensatory cephalic curve, compensatory curve on the caudal side, segmental kyphosis, coronal balance, sagittal balance, thoracic kyphosis, lumbar lordosis, and apical vertebra translation. Correlation analysis is used to evaluate the factors affecting the loss of judgment and correction effect, and the correlation indicators are included in the multi-factor Logistics regression.ResultsIn terms of radiographic indicators in the coronal plane, compared to preoperative values, significant improvements were observed in postoperative Cobb Angle of main curve (8.00°±4.62° vs. 33.30°±9.86°), Segmental Cobb angle (11.87°±6.55° vs. 31.29°±10.03°), Compensatory cephalic curve (6.22°±6.33° vs. 14.75°±12.50°), Compensatory curve on the caudal side (5.58°±3.43° vs. 12.61°±8.72°), coronal balance (10.95 mm ± 8.65 mm vs. 13.52 mm ± 11.03 mm), and apical vertebra translation (5.96 mm ± 5.07 mm vs. 16.55 mm ± 8.39 mm) (all P < 0.05). In the sagittal plane, significant improvements were observed in Segmental kyposis Angle (7.60°±9.36° vs. 21.89°±14.62°, P < 0.05) as compared to preoperative values. At the last follow-up, Segmental kyphosis Angle (6.09°±9.75° vs. 21.89°±14.62°, P < 0.05), Thoracic kyphosis (26.57°±7.68° vs. 24.06°±10.49°, P < 0.05) and Lumbar lordosis (32.12°±13.15° vs. 27.84°±16.68°, P < 0.05) had statistical significance compared with the preoperative department. The correlation analysis showed that the correction effect of the main curve Cobb angle was correlated with fixed segment length (rs=-0.318, P = 0.048), postoperative segment Cobb angle (rs=-0.600, P < 0.001), preoperative apical vertebra translation (rs = 0.440, P = 0.005), and spinal cord malformation (rs=-0.437, P = 0.005). The correction effect of segmental kyphosis was correlated with age (rs = 0.388, P = 0.037). The results of the multivariate logistic regression analysis revealed that postoperative segmental Cobb angle > 10° (OR = 0.011, 95%CI:0.001–0.234, P = 0.004), associated spinal cord anomalies (OR = 24.369, 95%CI:1.057-561.793, P = 0.046), and preoperative apical translation > 10 mm (OR = 0.012, 95%CI:0.000-0.438, P = 0.016) were influential factors in the progression of the main curve Cobb angle.ConclusionThe one-stage posterior hemivertebra resection and short-segment corrective fusion with internal fixation are effective means to treat congenital scoliosis. However, attention should be paid to the loss of correction and curve progression during follow-up. Patients with spinal cord malformation and a large preoperative apical vertebra translation have a greater risk of losing the correction after surgery.

An iterative loss correction method for deep learning with noisy labels

Noisy labelling is a prevalent issue in real-world data, often causing deep neural networks (DNNs) to overfit. Prior research in this area primarily relies on the accurate estimation of noise transition matrices, which is contingent on identifying anchor points in the clean data domain. However, current methods typically estimate the anchor points using information from the noisy labels, potentially resulting in poor estimation. In contrast, our novel method aims to enhance precision by developing an estimator that jointly learns the transition matrices and anchor points through iterative learning. Our approach is validated on the IMDB and MNIST datasets, proving to be more precise and effective than previous methods.

Early Short Segment Pedicle Screw Fixation Including Fractured Vertebra of Thoracolumbar Burst Fracture with Incomplete Spinal Cord Injury

Background: Fractures of the thoracolumbar region are the most common injuries of the vertebral column; among them burst fractures are the most frequent. Several studies were done to see the surgical outcome of thoracolumbar burst fracture hence surgery was recommended for a better outcome. So, the current study aimed to evaluate the clinical, functional, and radiological outcome of short-segment pedicle screw fixation including the fractured vertebral body. Objectives: The primary aim of this study is to comprehensively evaluate the functional and radiological outcomes of early short-segment pedicle screw fixation, particularly in cases involving fractured vertebrae in thoracolumbar burst fractures accompanied by incomplete spinal cord injuries. Materials &amp; Method: In this prospective observational study, 31 cases were included between April 2017 and July 2018 through non-randomized purposive sampling. All patients, aged 15 to 60 years, underwent posterior decompression and short-segment pedicle screw fixation, including the fractured vertebral body, within 21 days of the fracture. Postoperative functional outcomes were clinically assessed using the Oswestry Disability Index (ODI), Visual Analog Scale (VAS), American Spinal Injury Association (ASIA) scale, Denis Work Scale, and radiologically evaluated by Cobb's kyphotic angle, kyphotic deformation, Beck index, and Bridwell criteria. Postoperative follow-ups were conducted at the 6th, 12th, and 24th weeks. Results: In this study, 31 cervical spinal injury patients underwent operative treatment with a 3 to 12-month follow-up. Most were day laborers (35.48%), experiencing falls from height (80.65%), mainly at L1 (54.84%). Initial ASIA grade D improved to E (54.58%). Postoperatively, significant improvements in kyphotic angles, Beck index, and vertebral height were noted, with some correction loss at the final follow-up. Complications occurred in 22.58% of cases, including per-operative hemorrhage, dural tear, .......

Fracturing the Lateral Hinge Improves Radiographic Alignment and Does Not Affect Clinical Outcomes of the Minimally Invasive Akin Osteotomy.

Intraoperative fracture of the lateral cortex is common during Akin osteotomy. In a recent study, lateral cortex fracture did not impede healing or result in loss of correction in a combined cohort of open and percutaneous osteotomies stabilized by K-wire fixation. We hypothesize that undesired lateral cortex fracture will not affect radiographic correction and patient-reported outcomes in a percutaneous cohort stabilized by permanent, rigid screw fixation. Consecutive patients with hallux valgus who underwent first metatarsal osteotomy and percutaneous Akin osteotomy stabilized by permanent, rigid screw fixation between May 2020 and January 2022 were retrospectively reviewed. Patients were stratified based on fractured lateral cortex (FC) or its absence (nonfractured cortex [NFC]). Visual analog scale (VAS) and Foot Function Index (FFI) were used to assess pain and patient-reported outcomes at 1-year follow-up. Patients were polled for satisfaction at 1-year follow-up by yes/no survey. Ninety-eight patients (89% female) were reviewed (98 feet; 43 NFC, 55 FC). Mean age was 48.3 years (range, 18-83 years). Mean preoperative VAS score was 7.5 and 7.7 in NFC and FC groups, which significantly decreased to 0.6 (P < .01) and 0.6 (P < .01), respectively. Mean total FFI was 53.9 and 54.2 and decreased to 17.9 (P < .01) and 17.2 (P < .01) in the NFC group and FC group, respectively. Overall, 97.8% of the NFC group and 96.4% of the FC group reported satisfaction.Mean HVA improved from 27.2 (16-42) degrees to 10.7 degrees (4-12) postoperatively in the NFC group. And in the FC group, HVA improved from 29.3 (19-39) degrees to 7.1 (4-12) degrees postoperatively. Postoperative HVA was significantly lower in the FC group (P < .05). In an exclusively percutaneous surgical cohort with correction maintained by rigid screw fixation, fracture of the lateral cortex is associated with improved postoperative radiologic alignment without detriment to patient-reported outcomes. Level III, retrospective cohort study.

Analysis of loss correction with the Gottesman-Kitaev-Preskill code

Analysis of loss correction with the Gottesman-Kitaev-Preskill code

Implant Removal After Medial Opening Wedge High Tibial Osteotomy Provides Implant-Related Pain Relief and Functional Improvement

PurposeTo (1) investigate the incidence of implant-related pain after medial opening wedge high tibial osteotomy (MOWHTO) using locking plate, (2) determine whether implant removal provides pain relief and functional improvement, and (3) evaluate bone healing and loss of correction after implant removal. Materials and MethodsBetween March 2014 and September 2017, MOWHTO was performed without bone graft. The inclusion criteria were patients who underwent implant removal after MOWHTO and were followed up for a minimum of 2 years. Patients were evaluated for implant removal one and two years after surgery. Clinical and functional evaluations were conducted to investigate implant-related pain using the visual analog scale, Lysholm score, and Tegner score. The radiographic indices measured were the gap-filling rate, weight-bearing line (WBL) ratio, hip-knee-ankle angle (HKAA), medial proximal tibial angle (MPTA), and posterior tibial slope angle (PTSA). ResultsA total of 55 patients were enrolled. Fifty-one (92.7%) patients experienced implant-related pain prior to implant removal, with 43 and eight patients reporting mild pain and moderate pain, respectively. At one and two years after implant removal, mild pain was six (10.9%) and five (9.1%) patients, respectively. The remaining patients reported no implant-related pain. Prior to implant removal and one year after implant removal, the Lysholm score improved from 77.0±5.6 to 86.8±5.7 (P<0.001), and the Tegner score improved from 3.3±1.2 to 3.9±1.3 (P<0.001). The mean gap-filling rate was 84.4%±9.6% at implant removal, and it significantly increased to 93.7%±5.4% and 97.4%±2.6% at one and two years after implant removal, respectively (P<0.001) For the WBL ratio, HKAA, MPTA, and PTSA, no statistical differences were found after implant removal. ConclusionThe incidence of implant-related pain after MOWHTO using medial proximal tibial locking plate was high. Implant removal provides pain relief and functional improvement (met minimal clinically important differences). Even after implant removal, bone healing progressed gradually without a loss of correction in all patients.

Rotational Changes Following Use of Direct Vertebral Rotation in Adolescent Idiopathic Scoliosis: A Long-Term Radiographic and Computed Tomography Evaluation.

A retrospective cohort study. To evaluate long-term rotational changes in the vertebrae of patients with adolescent idiopathic scoliosis (AIS) who underwent direct vertebral rotation (DVR). DVR using thoracic pedicle screws, a rotational corrective maneuver used in the surgical treatment of AIS, was introduced in 2004. Although DVR is considered to be the main axial corrective maneuver, the long-term rotational changes of vertebrae following this treatment are not well understood. A total of 135 vertebrae that underwent DVR using thoracic pedicle screws with a minimum five-year follow-up were retrospectively assessed for the vertebral rotation angle. The vertebral rotation of the apical vertebra (AV) and distal end vertebra (EV) was evaluated using the Nash-Moe scale, the rotational angle to the sacrum (RAsac), and the Aaro and Dahlborn method. The Student t test (paired means) was used for continuous variables, and the χ 2 test was used for categorical variables, as appropriate. A comparison of two and three groups used a one-way repeated measures analysis of variance, and the post hoc analysis used the Bonferroni test. The mean Nash-Moe scale of distal EV showed statistically significant differences between preoperative and postoperative values ( P =0.034) and no statistically significant difference between postoperative and last follow-up values ( P =1.000). The last follow-up RAsac of AV did not differ significantly from the preoperative RAsac of AV ( P =0.515). The last follow-up RAsac of distal EV was significantly lower than the preoperative RAsac of distal EV ( P =0.001). The Pearson correlation analysis showed that the last follow-up RAsac of distal EV was correlated with the Cobb angle of the main curve ( r =0.459, P =0.004), loss of correction ( r =0.541, P =0.001), and lowest instrumented vertebra tilt angle ( r =0.504, P =0.001). The rotation regression phenomenon in AV and rotation maintenance in distal EV were observed after DVR over an average 10-year follow-up. These findings suggest that the DVR in the surgical treatment of AIS has a positive long-term effect on the stabilization of distal EV from the point of view of axial rotation. 4.

Current limitations of gene therapy for rare pediatric diseases: Lessons learned from clinical experience with AAV vectors

Gene therapy using adeno-associated viral (AAV) vectors is a promising therapeutic strategy for multiple inherited diseases. Following intravenous injection, AAV vectors carrying a copy of the missing gene or the genome-editing machinery reach their target cells and deliver the genetic material. Several clinical trials are currently ongoing and significant success has already been achieved with at least six AAV gene therapy products with market approval in Europe and the United States. Nonetheless, clinical trials and preclinical studies have uncovered several limitations of AAV gene transfer, which need to be addressed in order to improve the safety and enable the treatment of the largest patient population. Limitations include the occurrence of immune-mediated toxicities, the potential loss of correction in the long run, and the development of neutralizing antibodies against AAV vectors preventing re-administration. In this review, we summarize these limitations and discuss the potential technological developments to overcome them. © 2023 Published by Elsevier Masson SAS on behalf of French Society of Pediatrics.

Modified French Osteotomy for Cubitus Varus Correction: Our Experience

Background: Various fixation techniques have been described for osteotomy for correction of cubitus varus. Kirschner-wiring (K-wiring) was used in the past for fixation; however, rates of fixation failure and pin-track infection were high. Fixation with two screws and a figure-of-eight wiring provides a stable fixation in children younger than 15 years. Herein, we used a modified lateral approach and a figure-of-eight construct with two screws and evaluated the outcome.&#x0D; Methods: A case series comprising 35 patients out of the total of 54 patients who underwent modified French osteotomy between January 2013 to December 2021 was conducted retrospectively. Functional outcomes were assessed using the modified Mayo Elbow Performance Scoring (MEPS) system.&#x0D; Results: There were 22 male and 13 female subjects in the study group. We had excellent results in 16 cases, good outcomes in 13 cases, and fair outcomes in 6 cases. Superficial infection was seen in three patients and four patients had occasional negligible pain. In addition, there was no loss of correction or fixation failures in our study.&#x0D; Conclusion: Modified French osteotomy using two screws and figure-of-eight wiring is a simple and safe procedure that yields satisfactory outcomes. A careful preoperative planning, sufficient surgical technique, and stable fixation are key to achieving satisfactory functional outcomes.

Arthrodesis of the interphalangeal joints of the hand by two-dimensional intraosseous wiring

BackgroundNumerous techniques for arthrodesis have been described to fix interphalangeal (IP) joints, and the fixation method should be considered on a case-by-case basis. This study aimed to investigate the availability of IP joint arthrodesis of the hand, using a two-dimensional intraosseous wiring (two-DIOW) method.MethodsA total of 43 joints (19 thumb IP joints, 9 proximal finger interphalangeal (PIP) joints and 15 distal interphalangeal (DIP) joints in 29 patients with a mean age of 66 years (range, 24–85 y) were retrospectively analyzed. All operations were performed with two-DIOW method. We evaluated the bone union rate, correction loss, presence of any surgical complications, and oral steroid use in cases of joint fixation using the two-DIOW method.ResultsOf these 43 digits, 42 achieved bone union (97.7%). Non-union was seen in a thumb IP joint of mutilans rheumatoid arthritis. Mean correction loss of deviation was 1.0°, and flexion or extension angulation was 1.6° in the direction of extension. Surgical complications included mild nail deformity in 2 digits and wire irritation necessitating wire removal in 2 digits. Oral steroids were used for 18 of the 43 digits, including 2 digits complicated by nail deformities. There was no infection and skin necrosis in all digits with or without steroid use.ConclusionsThe two-DIOW method appears to offer an effective method of IP joint fixation, but caution should be exercised in digits of severe joint destruction and in the treatment of wire knot.

Constraint loss correction: Enhancing transferability of fracture toughness of Eurofer97 compact tension specimens between specimen sizes

This paper proposes and implements a constraint loss correction as a supplement to the ASTM correction factor for the master curve method (ASTM-E1921) for Eurofer97 reduced activation steel in order to enhance the transferability of results between compact tension (CT) specimen sizes. To facilitate the acquisition and scalability of reliable fracture toughness data from one specimen size to another and to apply the Master-Curve method with confidence when using small specimens, the difference in the structure of the crack tip stress field between large and small specimens was modeled. The stress intensity factors and critical volumes/stresses of two specimen sizes (1 T and 0.18 T) were calculated with 3D finite element simulations run over a large displacement range and at a temperature range of −120 to −80 °C and the results were compared with real data from a database of toughness tests of Eurofer97 steel. The K values from a miniaturized specimen without or with ASTM correction and with the proposed combined correction with constraint loss factor (which is variable over the entire loading range) were compared with simulated CT-1 T stress intensity values. It was found that this new correction factor was accurate up to a target toughness of 200 MPa.m1/2, which represents a major improvement on the current state of the art.

Is restoration of vertebral body height after vertebral body fractures and minimally-invasive dorsal stabilization with polyaxial pedicle screws just an illusion?

Thoracolumbar spine fractures often require surgical treatment as they are associated with spinal instability. Optimal operative techniques and treatment are discussed controversially. Aim of our prospective cohort study was to investigate the sagittal alignment after reduction, the secondary loss of reduction and the subjective outcome as well as the causal correlation of these parameters after minimally invasive stabilization of thoracic and lumbar fractures with polyaxial pedicle screws. In a single-center study, a total of 78 patients with an average age of 61 ± 17years who suffered a fracture of the thoracic or lumbar spine were included and subjected to a clinical and radiological follow-up examination after 8.5 ± 8months. The kyphotic deformity was measured by determining the vertebral body angle, the mono- and bi-segmental wedge angle at three time points. The patients' subjective outcome was evaluated by the VAS spine score. After surgical therapy, a significant reduction of the traumatic kyphotic deformity was shown with an improvement of all angles (vertebral body angle: 3.2° ± 4.4°, mono- and bi-segmental wedge angle: 3.1° ± 5.6°, 2.0° ± 6.3°). After follow-up, a significant loss of sagittal alignment was observed for all measured parameters with a loss of correction. However, no correlation between the loss of reduction and the subjective outcome regarding the VAS spine scale could be detected. The minimally invasive dorsal stabilization of thoracic and lumbar spine fractures with polyaxial pedicle screws achieved a satisfactory reduction of the fracture-induced kyphotic deformity immediately postoperatively with a floss of reduction in the further course. However, maybe the main goal of this surgical procedure should be the prevention of a complete collapse of the vertebral body instead of a long-lasting restoration of anatomic sagittal alignment. II.

Two-year results of single-level fixation with lateral mass screws for cervical degenerative spondylolisthesis: patient series.

In surgery for cervical spondylotic myelopathy (CSM) with spondylolisthesis, there is no consensus on the correction and fixation for spondylolisthesis. The authors retrospectively studied whether the correction of single-level fixation with lateral mass screws (LMSs) could be maintained. The records of patients with CSM with spondylolisthesis who had been treated with posterior decompression and single-level fusion with LMSs from 2017 to 2021 were retrospectively reviewed. Radiographic measurements included cervical parameters such as C2-7 lordosis, T1 slope, and the degree of spondylolisthesis (percent slippage) before surgery, immediately after surgery, and at the final observation. Ten cases (mean age 72.8 ± 7.8 years) were included in the final analysis, and four cases (40%) were on hemodialysis. The median observation period was 26.5 months (interquartile range, 12-35.75). The mean percent slippage was 16.8% ± 4.7% before surgery, 5.3% ± 4.0% immediately after surgery, and 6.5% ± 4.7% at the final observation. Spearman's rank correlation showed a moderate correlation between preoperative slippage magnitude and correction loss (r = 0.659; p = 0.038). Other parameters showed no correlation with correction loss. For CSM with spondylolisthesis, single-level fixation with LMSs achieved and maintained successful correction in the 2-year observation.

Surgical management of neck of femur fractures in patients younger than sixty-five years: a comparative study of three fixation methods.

Several surgical implants have been used for the treatment of neck of femur fracture (NOF) in younger patients such as dynamic hip screw (DHS) and cannulated compression screw. However, the superiority of one or another osteosynthesis device remains a matter of debate. The aim of this work is to evaluate and compare three fixation modalities: Cannulated Hip Screws (CHS), DHS and DHS associated to anti-rotating screw for surgical treatment of femoral neck fracture in young adults. It is a retrospective comparative study of three series of NOF fractures treated surgically over a period of ten years; including young adult patients (age > 18 years and < 65 years) treated conservatively using closed or open reduction and internal fixation. All types of NOF fractures according to Garden classification were included. Pathological, basi-cervical fractures and fractures on previously operated hips were excluded. The minimum follow-up recommended was two years. Clinical evaluation was based on the Postel Merle d'Aubigné score (PMA), the visual analogue scale (VAS), the Parker score, and the Hip Disability and Osteoarthritis Outcome Score (HOOS score). Reduction quality was assessed on X-rays. Our series included 72 patients that were divided in three groups: Group A: Fixation using cannulated hip screws (33 patients). Group B: Fixation using DHS only (21 patients). Group C: Fixation using DHS associated to anti-rotation screw (18 patients). The patients of group A had better PMA and VAS scores, but there was no statistically significant difference. However, a significant difference (p=0.001) was found for the HOOS score. The fractures treated with DHS associated with anti-rotating screws, had the highest loss of reduction in the vertical axis (Yp) with the highest femoral head collapse (Zp) values. Group A had the lowest loss of reduction in the horizontal axis (Xp). There was no significant difference between the three methods of osteosynthesis in terms of loss of correction though. We found comparable results in terms of healing and complication rates and loss of reduction for the three groups with no significant difference. However, the HOOS score was significantly better in the cannulated hip screw group.

Significant Early Loss of Correction in Modified Lapidus Compared to Original Lapidus for Hallux Valgus

Category: Bunion; Other Introduction/Purpose: The Lapidus procedure (first tarsometatarsal joint (TMT1) fusion) is an established treatment for correcting hallux valgus with 1st ray hypermobility. The original Lapidus (OL) technique involves fusing the TMT1 joint and first metatarsal base to the second, while the modified Lapidus (ML) technique involves fusing only the TMT1 joint. The purpose of this study was to investigate whether the ML procedure results in an early loss of correction. Methods: This retrospective study analyzed the outcomes of 45 feet in 40 patients with hallux valgus who underwent either the ML (21 feet) or OL (24 feet) procedure between 2014 and 2022 at a single center. All fixations were performed with 3.5 cortical screws, except for 9 cases that were fixed with a plantar locking plate. Differences in the immediate postoperative (6 weeks) and postoperative (6 months) intermetatarsal angle (IMA) and hallux valgus angle (HVA) were analyzed using Mann-Whitney tests, and complications were reported. Results: The mean preoperative IMA and HVA for the OL were 15.8° ± 3.5° and 36.4° ± 9.5°, respectively, and 14.5° ± 2.3° and 33.0° ± 7.0° for the ML. The immediate postoperative IMA and HVA were similar for both procedures (7.2° ± 2.0° and 7.7° ± 4.3° for OL, 7.3° ± 2.1° and 8.5° ± 5.5° for ML). Although from 6 weeks to 6 months postoperatively, the loss of correction of the HVA did not differ between both procedures (4.2° for OL, 5,6° for ML), the IMA loss of correction was significantly higher in the ML (1.1° ± 1.4° vs 0.5° ± 1.1°) (p &lt; 0.05). One case of delayed union was reported in the OL group, but it did not require revision. Conclusion: The study results suggest that the ML procedure does not provide the same stability as the OL procedure in the early postoperative period, as there was a significantly greater early loss of correction of the IMA at 6 months postoperatively in the ML group compared to the OL group. Although there were no differences in the loss of correction of the HVA angle (HVA), an observed loss of 5 degrees remains a concern. Further studies are necessary to better understand the indications of the modified and original procedures.

Open reduction and Kirschner wire fixation method using a cylindrical block of unidirectional porous β-tricalcium phosphate for tongue-shaped calcaneal fracture: Report of three cases

The artificial bone grafts are performed on the defect after reduction of the calcaneal fracture. Generally, it is an artificial bone graft with an implant, and there are a few reports of an artificial bone graft without an implant. We report three cases (42-year-old male, 67-year-old male, 21-year-old female) of a tongue-shaped calcaneal fracture treated using a cylindrical unidirectional porous β-tricalcium phosphate artificial bone (Affinos®, Kurare co Ltd., Hyougo, Japan) to surgically repair bone defects after reduction. The bone defect is often observed when fracture is reduced in calcaneal fracture. There were significant bone defects, which were then fixed using Affinos® (forming a cylindrical shape block; diameter 10 mm x height 20 mm) to support the bone fragment, an artificial β-tricalcium phosphate bone with a porosity of 57 % (pore size 25–300 μm), characterized by a novel unidirectional porous structure. Postoperative early rehabilitation started with partial load from 5 weeks after surgery and was full weight bearing at 9 weeks after surgery. There was no correction loss and good bone fusion was obtained. By 12 months postoperatively, patients were able to be walking without pain and absorption and bone fusion around the artificial bone were observed maintaining the morphology immediately after reduction. The result was a good clinical result of one excellent (92 points) and two good (81 and 84 points) 1 year after surgery in the postoperative AOFAS Ankle-Hindfoot Scale. Affinos® has a frost-like structure, which endows it with good tissue invasive properties because of the capillary effect. Moreover, it has excellent osteoconduction capability. In these 3 cases, Affinos® showed good strength, affinity, absorption, and bone substitution in a tongue-shaped calcaneal fracture. Further prospective studies are required to confirm our findings.

Midfoot and Hindfoot Charcot Deformity Correction is Well Maintained with Beam Fixation

Category: Midfoot/Forefoot; Diabetes Introduction/Purpose: Charcot arthropathy is a neurotraumatic foot disorder seen in patients with peripheral neuropathy. Surgical reconstruction via medial column arthrodesis with beams can restore plantigrade foot anatomy with decreased soft tissue dissection and improved bony compression. Methods: We identified 12 patients with midfoot (n=7) or hindfoot (n=5) Charcot who underwent medial column beaming arthrodesis between 2015 and 2021 b y one of two fellowship-trained foot and ankle surgeons at an academic medical center. Data collected from patient charts included demographics, medical history, complications, and reoperation rate. Meary’s angle was measured on lateral weightbearing radiographs preoperatively and up to two years postoperatively. Mean follow-up time was 2.50 (range, 1.04-6.98) years. Statistical analysis included correlation, two-tailed Student t-test, and Chi-squared test. Results: Meary’s angle was recorded preoperatively for 12 patients (19.3° ± 6.7°) and postoperatively at three months for 12 patients (4.0° ± 6.7°), at six months for 12 patients (7.1° ± 9.7°), at one year for 11 patients (6.1° ± 9.4°), and at two years for five patients (10.2° ± 6.4°). However, two (16.7%) patients showed a loss of deformity correction, which was demonstrated by a Meary’s angle that was greater at final follow-up than preoperatively. Overall complication, infection, reoperation rates were 50.0%, 41.7%, and 58.3%, respectively. Finally, dependent on preoperative ulceration, those with and without an ulcer did not differ in Meary’s angle at any time point, overall complication, infection, nor reoperation rate. Conclusion: Although the results showed a relatively high complication rate, the use of beaming arthrodesis was generally able to maintain a plantigrade foot and overall alignment, while decreasing the recurrence of plantar ulceration.

An inverse Jiles-Atherton model of nanocrystalline magnetic core for nanoseconds square pulsed magnetization.

The magnetic core is a key component of a linear transformer driver (LTD), and the accuracy of the core model affects the calculation of the LTD power flow and the prediction of the output waveform. In this paper, a magnetization model based on the inverse Jiles-Atherton (inverse J-A) model is developed and a particle swarm algorithm is used to identify the parameters and to obtain the variation of the parameters with the excitation characteristic. A nanoseconds square wave LTD magnetic core test platform was built to obtain the magnetization characteristics of nanocrystalline magnetic cores under different excitation characteristic parameters. Under square wave pulses, due to the presence of harmonic components, core loss is more complex. In view of the fitting deviation caused by the traditional J-A model not considering harmonic factors and anisotropy, a dynamic loss correction factor is proposed. Through a comparison of experimental and simulation results, this model can well reflect the magnetization process and has high accuracy in fitting dynamic hysteresis loops and predicting losses, which is important for guiding the design of a square pulse LTD.

Long-Term Results after Chiari Pelvic Osteotomy in the Skeletally Immature and the Role of the Anti-Chiari Effect.

Several authors observed a loss of correction after performing Chiari pelvic osteotomy (CPO) in young patients. Hence, the aim of this study was to answer two questions: (1) Does the Chiari pelvic osteotomy affect the development of the acetabulum in skeletally immature patients in the long term? (2) Is there any evidence of the previously described "Anti-Chiari" effect after a mean follow-up of 36 years? Data from 21 patients (27 hips) undergoing CPO before the age of 16 years were clinically assessed, and the evolution of radiological parameters over time was analyzed. The mean age at CPO was 11.2 years (±3; 4.4-15.7). The 20- and 30-year survival rates of the CPO were 100% and 92.6%, respectively. Mean postoperative medialization was 54% (±18; 23-99). The average osteotomy angle was 11° (±7; 2-28). No significant changes were found for the center-edge angle (CEA) and acetabular index (AI) over time; the angle of Idelberger and Frank (ACM) almost reached normal values at follow-up (FU); for the acetabular-head index (AHI), a slight shift toward the initial situation could be detected. The morphology of the acetabulum remained unchanged over time. The "Anti-Chiari effect" seems to be primarily caused by insufficient coverage of the femoral head rather than damage to the apophysis due to surgery.