-
Injury Jun 2024The majority of all proximal humeral fractures (PHFs) are treated non-surgically. Due to the risk of early secondary fracture displacement patients with non-surgically...
Low risk of early conversion to surgery in non-surgically treated proximal humeral fractures - An observational cohort study of 31,761 fractures from the Swedish Fracture Register.
INTRODUCTION
The majority of all proximal humeral fractures (PHFs) are treated non-surgically. Due to the risk of early secondary fracture displacement patients with non-surgically treated PHFs routinely undergo serial clinical and radiological evaluations. However, the value of these routine follow-up visits is unclear. This study aimed to examine the rate of early conversion to surgery in non-surgically treated PHFs. Moreover, the associations between patient and fracture characteristics and the risk of conversion to surgery were explored in order to assess the need for routine follow-ups.
METHODS
Data on all patients aged ≥18 years with a non-surgically treated PHF registered between 2013 and 2021 were extracted from the Swedish Fracture Register. Early change of treatment from non-surgical to surgical is an optional treatment modality in the SFR. The rate of early conversion to surgery within 60 days from injury was analyzed in relation to age and sex of the patient, energy level at injury and fracture morphology according to the AO/OTA classification.
RESULTS
A total of 31,761 primarily non-surgically treated PHFs (mean age 70 years: 76 % female) were included in the study. The overall rate of early conversion to surgery was 3.7 %. Younger age and increasing fracture severity were associated with a higher conversion rate to surgery. Patients ≥80 years and those with the three most common fracture types (A1, A2, and B1) had <2 % early conversion to surgery. In contrast, patients with C-type fractures, unstable/displaced fractures (A3, B2, and C2), or fracture dislocations (A1.3, B3, and C3) had a substantially higher risk (5.0-20 %) of early conversion.
CONCLUSION
The overall risk of early conversion to surgery in non-surgically treated PHFs is low and can be further predicted based on patient age and fracture morphology. These results could have implications regarding which patients are in need of routine follow-ups.
LEVEL OF EVIDENCE
Level II; Retrospective design; Prognosis study.
PubMed: 38897070
DOI: 10.1016/j.injury.2024.111679 -
European Journal of Radiology Jun 2024The trapeziometacarpal (TMC) joint is a complex joint, whose anatomy and function are different from the metacarpophalangeal joints of the long fingers. The stability of... (Review)
Review
INTRODUCTION
The trapeziometacarpal (TMC) joint is a complex joint, whose anatomy and function are different from the metacarpophalangeal joints of the long fingers. The stability of this joint is ensured at three levels by multiple structures: osteochondral, capsulo-ligamentous, and musculo-tendinous. The anatomical and biomechanical structures ensuring the stability of the TMC joint are perfectly evaluated on magnetic resonance imaging (MRI), with a high degree of confidence. All described ligaments are anatomically visible and perfectly assessed on MRI and ultrasound (US): the dorsoradial ligament, the posterior oblique ligament, the intermetacarpal ligament, the ulnar collateral ligament, the two bundles of the anterior oblique ligament (break ligament), as well as the superficial anterior oblique and deep anterior oblique ligaments.
METHODOLOGY
This educational review assesses the TMC joint anatomy using high-field MRI and US compared with cadaveric specimens as well the biomechanics of this joint. In addition, it highlights pathological patterns of traumatic (sprain, dislocation, and fractures) and degenerative diseases.
RESULTS AND CONCLUSION
Knowledge of TMC joint anatomy is crucial to the radiologists' understanding and assessment of various traumatic and degenerative pathologies, and thus helps clinicians and surgeons choose the appropriate treatment.
PubMed: 38897054
DOI: 10.1016/j.ejrad.2024.111561 -
Frontiers in Pediatrics 2024The role of cardiac left ventricle (LV) dysfunction in children with congenital diaphragmatic hernia (CDH) has gained increasing attention. The hernia allows abdominal...
INTRODUCTION
The role of cardiac left ventricle (LV) dysfunction in children with congenital diaphragmatic hernia (CDH) has gained increasing attention. The hernia allows abdominal mass to enter thorax and subsequently both dislocating and compressing the heart. The pressure on vessels and myocardium alters blood flow and may interfere with normal development of the LV. A dysfunctional LV is concerning and impacts the complex pathophysiology of CDH. Hence, assessing both the systolic and diastolic LV function in the newborn with CDH is important, and it may add value for medical treatment and prognostic factors as length of stay (LOS) in pediatric intensive care unit (PICU). LV strain is considered an early marker of systolic dysfunction used in the pediatric population. Left atrial (LA) strain is an echocardiographic marker of LV diastolic dysfunction used in the adult population. When filling pressure of the LV increases, the strain of the atrial wall is decreased. We hypothesized that reduced LA strain and LV strain are correlated with the LOS in the PICU of newborns with CDH.
METHODS
This retrospective observational cohort study included data of 55 children born with CDH between 2018 and 2020 and treated at Karolinska University Hospital, Sweden. Overall, 46 parents provided consent. Echocardiograms were performed in 35 children <72 h after birth. The LA reservoir strain (LASr), LV global longitudinal strain, LV dimensions, and direction of blood flow through the patent foramen ovale (PFO) were retrospectively assessed using the echocardiograms.
RESULTS
Children with LASr <33% ( = 27) had longer stays in the PICU than children with LA strain ≥33% ( = 8) (mean: 20.8 vs. 8.6 days; < 0.002). The LASr was correlated with the LOS in the PICU (correlation coefficient: -0.378; = 0.025). The LV dimension was correlated with the LOS (correlation coefficient: -0.546; = 0.01). However, LV strain was not correlated to LOS.
CONCLUSION
Newborns with CDH and a lower LASr (<33%) had longer stays in the PICU than children with LASr ≥33%. LASr is a feasible echocardiographic marker of diastolic LV dysfunction in newborns with CDH and may indicate the severity of the condition.
PubMed: 38895191
DOI: 10.3389/fped.2024.1404350 -
Orthopaedic Journal of Sports Medicine Jun 2024Patellar fracture, femoral physis injury, and recurrent instability are concerning complications in medial patellofemoral ligament (MPFL) reconstruction (MPFLR)...
Outcomes of an All-Soft Tissue Fixation Technique for Reconstruction of the Medial Patellofemoral Complex Using Double-Bundle Quadriceps Tendon Autograft for Recurrent Patellar Dislocation in Skeletally Immature Patients.
BACKGROUND
Patellar fracture, femoral physis injury, and recurrent instability are concerning complications in medial patellofemoral ligament (MPFL) reconstruction (MPFLR) techniques for recurrent patellar dislocation in children and adolescents.
PURPOSE
To evaluate the outcomes of an anatomic all-soft tissue fixation technique for reconstruction of the medial patellofemoral complex (MPFC) using a double-bundle quadriceps tendon (QT) autograft for recurrent patellar dislocation in skeletally immature patients.
STUDY DESIGN
Case series; Level of evidence, 4.
METHODS
This retrospective study involved 24 skeletally immature patients (24 knees; 16 women and 8 men; age range, 9.5-15 years) with recurrent patellar dislocation who underwent MPFC reconstruction using a double-bundle QT autograft between September 2018 and January 2021. Only soft tissue suture fixation was used on the femoral and patellar sides of the 2 bundles of the QT. Radiographs, computed tomography, and magnetic resonance imaging were used to evaluate physeal status, lower limb alignment, patellar height and tilt, trochlear morphology, tibial tubercle-trochlear groove distance, and any associated knee pathology. Functional outcomes were assessed with the Kujala score, the visual analog scale (VAS) for pain, and the grading system of Insall et al..
RESULTS
The mean follow-up time was 40 ± 9.6 months (range, 28-56 months). At the final follow-up, the Kujala and VAS pain scores showed a significant improvement versus preoperative scores ( < .001), and the passive lateral patellar glide showed a significant reduction ( < .001). All patients had negative apprehension and J signs. Of the 24 patients, 23 regained full range of motion, while 1 patient had a knee flexion deficit. The patellar tilt angle improved significantly at the final follow-up ( < .001). There was no patellar fracture, femoral physis injury, or recurrence of patellar dislocation. According to the grading system of Insall et al, the results were excellent in 15 knees (62.5%), good in 8 knees (33.3%), fair in 1 knee (4.2%), and no knees showed poor results.
CONCLUSION
Reconstruction of the MPFC using a double-bundle QT autograft with an all-soft tissue fixation technique was an effective method for treating patellar instability in skeletally immature patients.
PubMed: 38895137
DOI: 10.1177/23259671241259051 -
Orthopaedic Surgery Jun 2024Total hip arthroplasty (THA) combined with proximal femoral reconstruction is a novel osteotomy technique developed to address severe hip deformities. There is a paucity...
OBJECTIVE
Total hip arthroplasty (THA) combined with proximal femoral reconstruction is a novel osteotomy technique developed to address severe hip deformities. There is a paucity of robust clinical and radiological evidence regarding the outcomes of this novel osteotomy technique. This study aimed to evaluate the clinical and radiological outcomes of THA combined with proximal femoral reconstruction during the early follow-up.
METHODS
This is a retrospective case series of 63 hips who underwent THA combined with proximal femoral reconstruction at a single institution between January 2020 and July 2023. The mean age of patients was 39.6 ± 12.6 years. The mean follow-up was 25.6 ± 3.8 months. Surgical characteristics and perioperative variables were evaluated to assess the efficacy of this technique. Harris hip score (HHS) was utilized to evaluate hip function. Leg length discrepancy (LLD) was evaluated in X-ray. The incidence of major adverse events including deep vein thrombosis (DVT), osteolysis, nonunion of the osteotomy, intraoperative femoral fracture, and infection was also evaluated. Paired-samples t-test was used to compare preoperative and postoperative HHS and LLD.
RESULTS
The mean operative time was 125.1 min. The mean size of the acetabular components used was 45.2 mm, and the stem size was 7.5. The primary friction interface was ceramic-on-ceramic, accounting for 92.1% of cases. The average length of hospital stay was 8.5 days. The mean cost of treatment was 46,296.0 Yuan. There was a significant improvement in postoperative HHS (p < 0.001) and LLD (p < 0.001) compared to preoperative values. The incidence of deep venous thrombosis was 4.8%; osteolysis rates for the cup and stem were 4.8% and 6.4%, respectively. The non-union and dislocation rates were 1.6% and 3.2%, respectively. There was no incidence of postoperative infection.
CONCLUSION
The novel osteotomy surgical procedure yields reliable and impressive clinical and radiological outcomes, with minimal complications. We advocate for its use in complex primary THA cases involving severe proximal femoral deformities.
PubMed: 38894527
DOI: 10.1111/os.14136 -
Materials (Basel, Switzerland) Jun 2024With the development of the petroleum industry, the demand for materials for oilfield equipment is becoming increasingly stringent. The strength increase brought about...
With the development of the petroleum industry, the demand for materials for oilfield equipment is becoming increasingly stringent. The strength increase brought about by time strengthening is limited in meeting the needs of equipment development. The GH3625 alloy with different strength levels can be obtained through cold deformation and heat treatment processes. A study should be carried out to further develop the potential mechanical properties of GH3625. In this study, the GH3625 alloy was cold drawn with different reductions in area (0-30%) and heat treated, and its mechanical properties were tested. The microstructure of the alloy during deformation and heat treatment was characterized by methods such as optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) based on the principles of physical metallurgy. The strength increase caused by dislocation strengthening was calculated from the dislocation density, tested by X-ray diffraction (XRD). The calculated value was compared to the measured value, elucidating the strengthening effect of cold deformation and heat treatment. The results showed that the yield strength and yield ratio of the cold-drawn alloy significantly reduced after aging at 650 °C and 760 °C. Heat treatment can make a cold-deformed material recover, ablate dislocations, and greatly reduce the dislocation density in the microstructure of the GH3625 alloy, which was the main factor in the decrease in yield strength. The work-hardening gradient of the cold-drawn material varied greatly with different reductions in area. When the reduction in area was small (10%), the hardness gradient was obvious. When it increased to 30%, the alloy was uniformly strengthened as the deformation was transmitted to the axis. This study can provide more mechanical performance options for GH3625 alloy structural components in the petrochemical industry.
PubMed: 38894018
DOI: 10.3390/ma17112754 -
Materials (Basel, Switzerland) Jun 2024Novel Nb-Si-based alloys with heterogeneous layers that have the same composition (Nb-16 at.%Si) but different phase morphologies were designed in this work....
Novel Nb-Si-based alloys with heterogeneous layers that have the same composition (Nb-16 at.%Si) but different phase morphologies were designed in this work. Heterogeneous layered structure (HLS) was successfully fabricated in Nb-16Si alloys by layering composite powders after various degrees of mechanical alloying (6 h, 12 h, 18 h, and 24 h) alternately and subsequent spark plasma sintering (SPS). The influence of HLS on the fracture behavior at both room and elevated temperature was investigated via single-edge notched bending (SENB) and high-temperature compression, respectively. The results show that the diversified HLS is obtained by combining hard layers containing fine equiaxed crystals and/or soft ones with coarse lamellar niobium solid solution (Nbss). By affecting the crack propagation in SENB, HLS is favorable for improving the fracture toughness and exhibits a significant increase compared with the corresponding homogenous microstructure. Moreover, for the same HLS, a more excellent performance is achieved when the initial crack is located in the soft layer and extended across the interface to the hard one through crack bridging, crack deflection, crack branching, and shielding effect. Fracture starts in the soft layer (from powders of ball-milled for 12 h) of a 12-24 alloy, and a maximum value (14.89 MPa·mm) is consequently obtained, which is 33.8% higher than that of the homogeneous Nb-16Si alloy. Furthermore, the heterogeneous layered alloys display superior high-temperature compression strength, which is attributable to the dislocation multiplication and fine-grained structure. The proposed strategy in this study offers a promising route for fabricating Nb-Si-based alloys with optimized and improved mechanical properties to meet practical applications.
PubMed: 38894000
DOI: 10.3390/ma17112735 -
Materials (Basel, Switzerland) Jun 2024The microstructure and texture evolution of Cu-Ni-P alloy after cold rolling and annealing at 500 °C was studied by electron backscattering diffraction (EBSD). The...
The microstructure and texture evolution of Cu-Ni-P alloy after cold rolling and annealing at 500 °C was studied by electron backscattering diffraction (EBSD). The equiaxed grain is elongated and the dislocation density increases gradually after cold rolling. The grain boundaries become blurred and the structure becomes banded when the reduction in cold rolling reaches 95%. A typical rolling texture is formed with the increase in deformation amount in cold rolling. The deformation structure gradually disappeared and recrystallized new grains were formed after annealing at 500 °C. The recrystallization nucleation mechanism of Cu-Ni-P alloy at 60% reduction is mainly a bow nucleation mechanism. A shear band begins to form after annealing at 80% reduction. The shear band becomes the preferred nucleation location with the increase in reduction. Most adjacent recrystallized grains growing in the shear band have a twin relationship.
PubMed: 38893969
DOI: 10.3390/ma17112696 -
Materials (Basel, Switzerland) May 2024This study subjected nuclear-grade 20# pipeline steel to cyclic freeze-thaw ice plugging tests, simulating the plastic deformation experienced by pipes during ice plug...
This study subjected nuclear-grade 20# pipeline steel to cyclic freeze-thaw ice plugging tests, simulating the plastic deformation experienced by pipes during ice plug removal procedures. Subsequently, the dislocation morphology and mechanical properties of the specimens post cyclic ice plugging were examined. The cyclic ice plugging process led to an increase in the dislocation density within the specimens. After 20 and 40 cycles of ice plugging, the internal dislocation structures evolved from individual dislocation lines and dislocation tangles to high-density dislocation walls and dislocation cells. These high-density dislocation walls and cells hindered dislocation motion, giving rise to strain hardening phenomena, thereby resulting in increased strength and hardness of the specimens with an increasing number of ice plugging cycles. In addition, a large stress field was generated around the dislocation buildup, which reduced the pipe material's plastic toughness. The findings elucidate the effects of cyclic ice plugging on the microstructure and properties of nuclear-grade 20# pipeline steel, aiming to provide a theoretical basis for the safe and stable application of ice plugging technology in nuclear piping systems.
PubMed: 38893906
DOI: 10.3390/ma17112642 -
Materials (Basel, Switzerland) May 2024The short-chain forming process using rotary swaging (RS) is an important method of achieving the manufacturing of lightweight axles. Axle steel, like 42CrMo, is widely...
The short-chain forming process using rotary swaging (RS) is an important method of achieving the manufacturing of lightweight axles. Axle steel, like 42CrMo, is widely used in many types of axles and shafts; however, there is no existing research on rotary-swaged axle steel's mechanical properties. It makes sense to carry out a comprehensive study on the effect of RS on the mechanical behaviors of axle steel rods. In this study, a 42CrMo steel rod was processed by RS through ten passes. The tensile properties, torsion properties, compression properties, and fatigue properties were tested. There was an overall improvement in the torsional and fatigue performance after RS. Combined with a finite element analysis (FEM), the uneven distribution of the dislocations and existence of the elongation material were inferred to have caused the different modes of the mechanical behaviors. Fracture surfaces were analyzed and the results showed that the fracture pattern had changed. There existed a competitive relation between the internal fatigue cracks and external cracks, which could be attributed to uneven strain hardening. This research proved the advantages of RS in the processing of axle parts, which mainly benefitted the torsional working conditions, and provided evidence for a new processing route for lightweight axles with RS.
PubMed: 38893789
DOI: 10.3390/ma17112525