Leg Length Research Articles

Early results of primary total hip arthroplasty performed in young adults at a regional Saudi-Arabian orthopedics center: a prospective observational study

Background. Younger patients undergoing primary total hip arthroplasty (THA) have different indications and outcomes than elderly patients. Furthermore, studies reporting the results of THA in young patients are scarce in our area. The aim of the study is to report the early experience and clinical results after total hip arthroplasty in patients ≤40 years old from a regional Saudi-Arabian hospital as a representative of the Arab (Middle Eastern) population. Methods. We conducted a prospective observational study over one year by following all patients (≤40 years) who underwent primary THA at a regional Saudi-Arabin orthopedics center. Twenty-five patients (a mean age of 31.60±6.07 years, and 14 (56%) were males) were eligible for final inclusion. The functional assessment was performed according to the Harris Hip Score (HHS), leg length discrepancy (LLD) was evaluated, and complications at any point were reported. Results. The commonest indication was advanced avascular necrosis (28%) followed by post-traumatic osteoarthritis (24%) and rheumatoid arthritis (24%). Cementless fixation was utilized in 20 (80%) THAs, and the bearing surface was either metal- or ceramic-on-polyethylene in 92% of THAs. After a mean follow up of 20.0±4.5 months, HHS improved from a pre-operative mean of 29.20±5.29 to 85.48±7.18 (p = 0.0001). Excellent and good results were reported in 84%. All working patients (52%) returned to their jobs after THAs. The leg length discrepancy improved significantly from a pre-operative mean of 2.12±1.01 cm to the last follow up mean of 0.72±0.4 cm, p = 0.0001. Two (8%) patients had superficial wound infections at the time of suture removal, which were treated successfully by daily dressing and antibiotics. None required revision. Conclusions. Primary total hip arthroplasty is the option for managing end-stage hip disease, even in younger patients when hip preservation surgeries are invalid. Our results showed improved functional outcomes and a return to pre-disease daily activities in most patients, with considerably lower complication incidence.

Modular Stems in Revision Hip Arthroplasty: A Three-Step Technique

Background: Complications such as periprosthetic fractures necessitate challenging revision surgeries. In particular, femoral stem revisions can be complicated by poor bone quality, making primary stability and leg length restoration difficult to achieve. Modular fluted tapered stems (MFTSs) have emerged as a viable option for these complex cases. This study aims to describe a reproducible three-step technique for femoral stem revision using MFTSs. The technique focuses on (1) obtaining distal primary stability, (2) restoring leg length, and (3) ensuring overall implant stability. Materials and methods: We conducted a retrospective analysis of ten patients who underwent revision THA using this three-step technique, with a minimum follow-up of 12 months. The mean patient age was 70.7 years, and the average follow-up was 24.2 months. Limits were the small sample size, the lack of clinical outcomes and the short-term follow-up. Results: There was no subsidence, a mean leg length discrepancy of 4 mm (p: 0.604), and no dislocations. However, heterotopic ossifications (HOs) were observed in 25% of patients, although no trochanteric migrations occurred. One patient experienced an intraoperative femoral fracture, which was successfully treated. Conclusions: This three-step approach can break down the revision procedure, making it more accessible to surgeons. The findings suggest that this technique is effective in achieving reliable outcomes in femoral stem revisions, potentially improving the standard of care for patients requiring complex THA revisions.

Predicting Willow Planting Events by Conventional Machine Learning from GPS Data: Accuracy, Generalization Ability, and Potential for Improvement

Willow cultivation is an important activity that can provide greater amounts of cleaner and renewable energy. To support the development of this farming sector, data is required on the spatial distribution of planted plots, as well as on the performance of operations typically required in willow crop management. Unfortunately, this kind of data is largely unavailable, while documenting it is a challenging task. GPS data, which may be feasibly collected during operations, may be a good carrier of information not only to document the spatial location of plots, but also to learn about the frequency of typical events as specific to willow operational management. Based on a GPS dataset characterizing two plots, which was collected during planting operations and labelled manually (8,385 observations), a neural network was used in this study to spatially classify events such as driving (hereafter called D), maneuvering (hereafter called M), planting (hereafter called P), and being stopped (hereafter called S). Three models were trained and validated based on features such as GPS speed (hereafter called model S), GPS speed and leg length (hereafter called model S&L), and GPS speed, leg length, and heading (hereafter called model S&L&H), respectively. Classification performance was found to be impressive, with an overall accuracy of 92.0 (S), 92.1 (S&L), and 93.3% (S&L&H), respectively. The quality of the models was then checked visually using a dataset containing unseen data characterizing two plots of different cardinal orientation, indicating an acceptable generalization ability. The methods described in the paper may be useful when dealing with large datasets and limited resources and expertise in labelling the data manually, as they provide location and event specific data with high accuracy. Improvements in accuracy are possible by integrating the raw data in deep learning, an approach that should be explored further.

Effectiveness of Combined Intravenous and Periarticular Tranexamic Acid Compared to Intravenous Tranexamic Acid Alone for Decreasing Blood Loss in Simultaneous Bilateral Total Knee Arthroplasty

Background: There are advantages of simultaneous bilateral total knee arthroplasty (TKA), including reduced leg length discrepancy (LLD), better gait balance, and affordability. However, the main issue is excessive blood loss. Systemic effects are lessened by peri-articular injection of tranexamic acid (PA-TXA). Compared to the intravenous method (IV-TXA), it is claimed to produce better results. Objective: To evaluate the efficacy of IV-TXA + PA-TXA compared to IV-TXA alone in reducing blood loss during simultaneous bilateral TKA. Materials and Methods: Between December 2022 and April 2024, 60 simultaneous bilateral TKA procedures were enrolled at Charoenkrung Pracharak Hospital. The control group, which was IV alone, and the study groups, which was IV-TXA plus PA-TXA, were randomly assigned, and postoperative follow-up was conducted to monitor 24 hours blood draining and total blood loss at 72 hours, blood transfusion, and complications over a 3-month period. Results: The mean age was 68.28±6.97 years, and 95.0% of the participants were female. A body mass index (BMI) of 26.09±4.70 was the average. The data were evaluated by blood transfusion, complications, total blood loss at 72 hours, and 24-hour blood draining, respectively. Although there was no significant difference between the control and study groups (p=0.227 and 0.773, respectively), there was a decrease in 24-hour blood draining and total blood loss after 72 hours. The operating time and postoperative transfusion did not differ significantly. Neither group experienced infection or deep vein thrombosis (DVT). Conclusion: Although not statistically significant, the combination of IV-TXA and PA-TXA appears to have lower total blood loss in simultaneous TKA as compared to the IV-TXA route alone. Keywords: Total knee replacement; Bilateral total knee replacement; Tranexamic acid; Peri-articular injection; Intravenous tranexamic acid

Femoral shaft fractures in preschool children: external fixation and elastic intramedullary nail treatments in clinical practice.

Surgical intervention in preschoolers with femoral shaft fractures has increased due to the evolving lifestyle. This study aimed to analyze and compare the efficacy of elastic intramedullary nailing and external fixation in treating femoral shaft fractures in children aged 2-5. Ninety-nine pediatric patients were categorized into the external fixator (EF) and the elastic intramedullary nail (ESIN) group based on surgical techniques. Data on follow-up, intraoperative parameters, postoperative complications, fracture features, and demographics were gathered and compared. The mean duration of follow-up was 32 months, ranging from 25 to 48 months. All fractures had healed completely and no instances of nonunion were observed. At the latest follow-up, within the EF group, there were instances of malunion, delayed union, and refracture, each occurring once. One case in every group exhibited a leg length difference above 2 cm. The external fixation group had a shorter operation duration (P = 0.04), fewer intraoperative fluoroscopy times (P < 0.01), earlier partial weight-bearing time (P < 0.01), and full weight-bearing time (P < 0.01), while a greater complication rate (29.8 vs. 14.3%, P = 0.07) compared with the ESIN group. The incidence of pin tract infection in the EF group was 21.1% (12/57) compared with 2.4% (1/42) in the ESIN group (P = 0.07). Eighty percent of the patients' families expressed concern about the residual scar after removing the EF. The ESIN group encounters fewer complications and positive aesthetic effects, making it a preferable treatment option in this specific patient population and fracture pattern. Level of evidence: Class III, retrospective comparative study.

2D analysis of tokamak divertor-plasma detachment-bifurcation with operational parameters and geometries

UEDGE simulations with density scans for various input power, transport coefficients and outer poloidal leg length are performed to study the conditions for the existence of a bifurcation-like drop of Te at the outer strike point, commonly referred to as a detachment cliff, when transitioning to a detached plasma from an attached plasma in the outer divertor as the upstream density increases (McLean et al., 2015). The simulation results show that a detachment cliff tends to occur with a higher power input regardless of diffusivities and leg length. Further analysis of change of plasma profiles at a cliff indicate that, in addition to the sharp reduction of the E×B drift fluxes in the outer divertor studied in Jaervinen et al., (2018), the substantial change of the Mach number in the outer divertor and the decrease of the outer mid-plane Te due to the radiation front moving across the separatrix into the confinement region above the X-point consistently occur for all UEDGE density scans that have a detachment cliff. UEDGE time-dependent simulation of the evolution of a detachment cliff shows that the rapid increase of radiation above the X-point occurs in a time scale of ∼0.3−0.5ms, which could possibly be the trigger for the formation of a detachment cliff, quicker than the Mach number change in a time scale of ∼1ms and the drop of Te in a time scale of ∼2−3ms in the outer divertor.

PHYSICS PERSPECTIVES ON HUMAN LOCOMOTION: INVESTIGATING THE MECHANICS OF WALKING PATTERNS

This study investigated the gait metric differences between males and females aged 18 to 22. Our investigation revealed some significant changes in gait metrics between the two genders. Firstly, males exhibited greater leg and step lengths than females. Males exhibited wider strides, suggesting typical anthropometric variations. Except for BMI and cadence, males had more variation in practically every other gait metric, whereas females had more variability. There was a non-significant positive connection between BMI and gait metrics such as height, stride length, and step width, with BMI having a minor effect on those measures. Overall, both genders showed a distinct pattern of variability, revealing individual variances in gait analysis across the same genders. A direct correlation was observed between the Froude number and height, indicating that individuals with a higher Froude number exhibit a more dynamic and faster walking style. This phenomenon can be ascribed to the biomechanical superiority that taller individuals may possess, enabling them to generate longer strides and achieve higher speeds. A thorough study of walking speed and gait parameters revealed difficulty in finding the right balance between stability, efficiency, and speed in human movement. Understanding these connections will help people develop more efficient training programs, assistive technologies, and more efficient and safe walking in general.

Forecasting Thermoelectric Power Generation through Utilization of Waste Heat from Building Cooling Systems based on Simulation

The transformation of sustainable energy use is one of the main challenges facing the world today. Waste heat from industrial processes and conventional power plants is one form of energy waste that is often wasted. In this context, research on thermoelectric energy conversion systems is a very relevant and important topic to research. This research investigates about the potential for utilizing thermoelectric elements with stacked materials that utilize waste heat from building cooling systems. Numerical simulation was chosen to carry out further analysis regarding the potential energy produced and the efficiency of the materials used. Three-dimensional design and ANSYS is used as a three-dimensional simulation analysis tool. The research results show that thermoelectric systems with stacked materials have the potential to produce energy from waste heat. Material (Cu2Se+, BiTe+) (Bi2S3-, CuFeS-) with 10mm legs has the highest output power of 32.82mW whereas (PbSe+, BiTe+) (Bi2S3-, AgInSe-) with a leg length of 20 mm has the highest efficiency value of 25.97%, and a power value of 6.92mW. Full system research can produce values ​​that more closely resemble actual conditions.

Greater Trochanter Tip as an Anatomical Reference to Minimize Leg Length Discrepancy following Hip Arthroplasty.

The objective of the current study is to introduce a proposed method and evaluate its efficacy using the greater trochanter (GT) tip rather than the lesser trochanter (LT) as an anatomical landmark to reduce leg length discrepancy (LLD) during performance of hip arthroplasty. Thirty-two patients who underwent hip arthroplasty were divided according to the GT group (n=17) and the LT control group (n=11); four patients were excluded. LLD was determined by assessing the vertical lengths parallel to the line connecting the lower margin of the teardrop to the most prominent part of the LT on a standing anteroposterior pelvic X-ray taken 30 days after the procedure. The mean and median LLD of the two groups were compared. Analysis of planning for femoral stem depth insertion and postoperative results was also performed. No significant differences in characteristics including age, sex, or body mass index were observed between the two groups. However, the type of arthroplasty differed significantly between groups (P=0.016). The mean postoperative LLD was significantly smaller in the GT group compared with the control group (P=0.004). The results of linear regression of femoral stem depth showed a significant association between intraoperative planning and postoperative measurement (t=2.705, r2=0.672, P=0.016). Preoperative measurement in determining femoral stem depth insertion using the GT tip as an anatomical reference can effectively minimize LLD in patients who underwent hip arthroplasty.

Evaluation of a deep learning software for automated measurements on full-leg standing radiographs

BackgroundPrecise lower limb measurements are crucial for assessing musculoskeletal health; fully automated solutions have the potential to enhance standardization and reproducibility of these measurements. This study compared the measurements performed by BoneMetrics (Gleamer, Paris, France), a commercial artificial intelligence (AI)-based software, to expert manual measurements on anteroposterior full-leg standing radiographs.MethodsA retrospective analysis was conducted on a dataset comprising consecutive anteroposterior full-leg standing radiographs obtained from four imaging institutions. Key anatomical landmarks to define the hip–knee–ankle angle, pelvic obliquity, leg length, femoral length, and tibial length were annotated independently by two expert musculoskeletal radiologists and served as the ground truth. The performance of the AI was compared against these reference measurements using the mean absolute error, Bland–Altman analyses, and intraclass correlation coefficients.ResultsA total of 175 anteroposterior full–leg standing radiographs from 167 patients were included in the final dataset (mean age = 49.9 ± 23.6 years old; 103 women and 64 men). Mean absolute error values were 0.30° (95% confidence interval [CI] [0.28, 0.32]) for the hip–knee–ankle angle, 0.75 mm (95% CI [0.60, 0.88]) for pelvic obliquity, 1.03 mm (95% CI [0.91,1.14]) for leg length from the top of the femoral head, 1.45 mm (95% CI [1.33, 1.60]) for leg length from the center of the femoral head, 0.95 mm (95% CI [0.85, 1.04]) for femoral length from the top of the femoral head, 1.23 mm (95% CI [1.12, 1.32]) for femoral length from the center of the femoral head, and 1.38 mm (95% CI [1.21, 1.52]) for tibial length. The Bland–Altman analyses revealed no systematic bias across all measurements. Additionally, the software exhibited excellent agreement with the gold-standard measurements with intraclass correlation coefficient (ICC) values above 0.97 for all parameters.ConclusionsAutomated measurements on anteroposterior full-leg standing radiographs offer a reliable alternative to manual assessments. The use of AI in musculoskeletal radiology has the potential to support physicians in their daily practice without compromising patient care standards.

Fluid balance of female para hockey players during simulated competition.

The purpose of this study was to characterize the hydration habits and fluid balance of female para-ice hockey players. Fifteen players [5 defense (D), 8 forwards (F), and 2 goalies (G)] volunteered to participate in the study (age: 26.3 ± 10.9 y; ht:155 ± 11 cm; arm length: 65 ± 8 cm; leg length: 88 ± 11 cm; trunk length: 66 ± 14 cm). Players were weighed pre- and postgame, while fluid intake and individual playing time (PT) was monitored throughout the game. On average, athletes arrived hydrated to the game (USG 1.019 ± 0.006) with 40% of players arriving dehydrated (USG >1.020). Mean playing time for forwards was 11:47-28:49 min:s (18:52 ± 5:48 min:s) and for defence 13:10-18:24 min:s (15:10 ± 2.05 min:s). Sweat loss was 0.96 ± 0.64 L (0.10-2.50 L) which exceeded net fluid intake (0.61 ± 0.37 L). Mean BM loss was 0.44 ± 0.9% (-2.1 to +0.9%) with 4 of 15 players (2 D, 1 F, 1 G) losing between 1.4 and 2.1% BM. Players preferred to drink water during the game compared to a carbohydrate electrolyte solution. 60% of athletes arrived hydrated to the game and drank enough fluid to prevent a BM loss <1%. Of note is that 40% of players arrived at the arena mildly dehydrated based on USG, and despite abundant opportunities to drink fluid during the game, 25% of players lost >1.3% BM due to sweat loss which may compromise physical and cognitive performance.

Reactivating Sleeping Intramedullary Nail in a 16-Year-Old Female with Polyostotic Fibrous Dysplasia: A Case Report on Complications and Potential Solutions

Background: Fibrous dysplasia (FD) is a rare condition in which normal spongy and cortical bone is replaced by non-neoplastic fibrous tissue, leading to weakened bone matrix and increased risk of pathological fractures and deformities. Treating these deformities poses a significant challenge for surgeons. While various cases of surgical stabilization and limb lengthening using intramedullary nails have been reported, there is limited evidence on the use of Motorized Intramedullary Limb-Lengthening Nails (MILLNs) in FD patients. This case report presents the clinical history of a patient with FD who underwent multiple surgical interventions to address severe lower limb length discrepancy (LLD) and angular deformity caused by multiple fractures. Case presentation: A sixteen-year-old Caucasian girl with polyostotic FD developed a severe post-traumatic LLD of 10 cm on the right side, associated with coxa vara, valgus knee, and patellar instability. The deformity of the proximal femur was addressed with a valgus and derotational femoral osteotomy. However, this procedure exacerbated the knee’s valgus deformity and only partially corrected the LLD, leading to the decision to proceed with femoral lengthening. A retrograde magnetic intramedullary nail (PRECICE, NuVasive) was utilized for this purpose. Approximately three months postoperatively, radiographs revealed the loosening of the proximal anchoring screw, while the nail had reached maximum distraction. We then proposed reactivating the previously implanted nail. Nine months after the final surgery, standing long-leg radiographs showed a residual shortening of 1 cm, with excellent healing at the fracture sites and the nail and screws remaining securely in place. The patient was monitored regularly, with the latest follow-up occurring four years and five months after the conclusion of the last lengthening procedure. Conclusions: This case report describes the reactivation of a MILLN in a patient with polyostotic fibrous dysplasia. While nail reactivation has been previously described in the literature, to our knowledge, it has not been reported for treating complications arising from FD. In cases of mechanical complications, this approach can equalize leg length discrepancies and correct deformities, avoiding additional invasive surgeries and reducing healthcare costs. As this is an off-label treatment, preoperative consent from both the patient and the parents is required.

Screening of SNP Loci Related to Leg Length Trait in Leizhou Goats Based on Whole-Genome Resequencing.

Leizhou goats can be classified into tall and short types based on their size and habits. The tall Leizhou goats are well-suited for grazing management due to their robust physique, while the dwarf types are smaller, grow rapidly, and are more appropriate for feeding management systems. In this study, whole-genome resequencing was conducted to identify genomic variants in 15 Tall-legged (TL) and 15 Short-legged (SL) Leizhou goats, yielding 8,641,229 high-quality SNPs in the Leizhou goat genome. Phylogenetic tree and principal component analyses revealed obvious genetic differentiation between the two groups. Fst and θπ analyses identified 420 genes in the TL group and 804 genes in the SL group. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses indicated that the phosphatidylinositol signaling system is associated with growth and development. Additionally, Genome-Wide Association Study (GWAS) analysis identified eight genes linked to leg length, including B4GALT7 and NR1D1. Notably, the NC_030818.1 (g.53666634T > C) variant was significantly associated with leg length traits, where the CC genotype was linked to shorter legs and the TT genotype to longer legs. This study identifies candidate genes and molecular markers, serving as a reference point for breeding and genetic improvement efforts in Leizhou goats and other goat breeds.

Anatomic Risk Factors for Initial and Secondary Noncontact Anterior Cruciate Ligament Injury: A Prospective Cohort Study in 880 Female Elite Handball and Soccer Players.

Anterior cruciate ligament (ACL) injury is one of the most severe injuries for athletes. It is important to identify risk factors because a better understanding of injury causation can help inform athletes about risk and increase their understanding of and motivation for injury prevention. To investigate the relationship between anatomic factors and risk for future noncontact ACL injuries. Cohort study; Level of evidence, 2. A total of 870, excluding 9 players with a new contact ACL injury and a player with a new noncontact ACL injury just before the testing, female elite handball and soccer players-86 of whom had a history of ACL injury-underwent measurements of anthropometrics, alignment, joint laxity, and mobility, including leg length, knee alignment, knee anteroposterior laxity, generalized joint hypermobility, genu recurvatum, and hip anteversion. All ACL injuries among the tested players were recorded prospectively. Welch t tests and chi-square tests were used for comparison between the groups (new injury group, which sustained a new ACL injury in the follow-up period, and no new injury group). An overall 64 new noncontact ACL injuries were registered. No differences were found between athletes with and without a new ACL injury among most of the measured variables. However, static knee valgus was significantly higher in the new injury group than in the no new injury group among all players (mean difference [MD], 0.9°; P = .007), and this tendency was greater in players with a previous ACL injury (MD, 2.1°; P = .002). Players with secondary injury also had a higher degree of knee hyperextension when compared with those previously injured who did not have a secondary injury (MD, 1.6°; P = .007). The anatomic factors that we investigated had a weak or no association with risk for an index noncontact ACL injury. Increased static knee valgus was associated with an increased risk for noncontact ACL injury, in particular for secondary injury. Furthermore, hyperextension of the knee was a risk factor for secondary ACL injury.

Impact of robot assistance on restoration of limb length and offset distance in total hip arthroplasty

To analyze the impact of robot assistance on the restoration of limb length and offset distance in total hip arthroplasty (THA). A retrospective analysis was conducted on the clinical data of 316 patients who underwent unilateral primary THA between September 2019 and August 2023. Among them, 117 patients underwent robot-assisted THA (group A), and 199 patients underwent conventional THA (group B). There was no significant difference between the two groups in the gender, age, or side of the hip replacement ( P>0.05); but there was a significant difference in the preoperative diagnosis ( P<0.05). The leg length discrepancy (LLD) and global offset (GO) dfference were measured on preoperative anteroposterior pelvic X-ray films, and absolute values were used for comparison between groups. The operations in both groups were successfully completed. Postoperative imaging measurements showed that the LLD and GO dfference in group A were significantly lower than those in group B ( P<0.05). Among them, group A had 32 cases (27.4%), 5 cases (4.3%), and 0 case (0) of LLD>3 mm, >5 mm, and >10 mm, respectively, while group B had 115 cases (57.8%), 75 cases (37.7%), and 22 cases (11.1%), respectively; and the differences in above indicators between groups were significant ( P<0.05). Group A had 40 cases (34.2%), 3 cases (2.6%), and 0 case (0) of GO dfference>5 mm, >10 mm, and >20 mm, respectively; group B had 103 cases (51.8%), 54 cases (27.1%), and 7 cases (3.5%), respectively. There was no significant difference in the proportion of patients with GO>20 mm between groups ( P>0.05), while there were significant differences in other indicators between groups ( P<0.05). Compared with traditional THA, robot assisted THA has more advantages in restoration of limb length and offset distance.

Structural analysis and fatigue prediction of harrow tines used in Canadian prairies

The Canadian prairies are renowned for their substantial agricultural contributions to the global food market. Harrow tines are indispensable in farming equipment, especially for soil preparation and weed control before planting crops. During operation, these tines are exposed to repetitive cyclic loading, which eventually causes fatigue failure. Commercially available three different harrow tines named 0.562HT, 0.625HT, and 0.500HT undergo an experimental fatigue evaluation and are validated through Finite Element Analysis (FEA). Fatigue life estimation for different deflections under various real-field deflections was carried out where 0.562HT showed groundbreaking life compared with others. The study results showed that the fatigue life is highly dependent on geometry, number of coils, pitch angle, leg length, and coil diameter. The 0.354HT model, developed to investigate the effect of wire diameter, closely resembles the 0.500HT model. The harrowing ability of the four different harrow tine models against identical deflections has been analyzed. Experimental fractured surfaces went through morphological investigation. This research has an impeccable impact on prairies’ agricultural acceleration by saving time and mitigating unpredictable fatigue failure often faced by farmers. Even the observed failure phenomena can serve as motivation to develop more reliable and durable harrow tines, which could increase agricultural efficiency.

Small heterodimer partner-interacting leucine zipper protein suppresses pain and cartilage destruction in an osteoarthritis model by modulating the AMPK/STAT3 signaling pathway

ObjectiveOsteoarthritis (OA) is a degenerative joint disease caused by the breakdown of joint cartilage and adjacent bone. Joint injury, being overweight, differences in leg length, high levels of joint stress, abnormal joint or limb development, and inherited factors have been implicated in the etiology of OA. In addition to physical damage to the joint, a role for inflammatory processes has been identified as well. Small heterodimer partner-interacting leucine zipper protein (SMILE) regulates transcription and many cellular functions. Among the proteins activated by SMILE is the peroxisome proliferator-activated receptor (PPAR) γ, which mediates the activities of CD4 + T helper cells, including Th1, Th2, and Th17, as well as Treg cells. PPAR-γ binds to STAT3 to inhibit its transcription, thereby suppressing the expression of the NF-κB pathway, and in turn, the expression of the inflammatory cytokines interferon (IFN), interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, which are sub-signals of STAT3 and NF-κB.MethodsOA was induced in control C57BL/6 mice and in C57BL/6-derived SMILE-overexpressing transgenic (SMILE Tg) mice. The protein expression levels in the joint and spleen tissues were analyzed by immunohistochemistry and immunofluorescence images. In addition, flow cytometry was performed for detecting changes of the changes of immune cells.ResultsLess cartilage damage and significantly reduced levels of OA biomarkers (MMP13, TIMP3 and MCP-1) were observed in SMILE Tg mice. Immunohistochemistry performed to identify the signaling pathway involved in the link between SMILE expression and OA revealed decreased levels of IL-1β, IL-6, TNF-α, and phosphorylated AMPK in synovial tissues as well as a significant decrease in phosphorylated STAT3 in both cartilage and synovium. Changes in systemic immune cells were investigated via flow cytometry to analyze splenocytes isolated from control and SMILE Tg mice. SMILE Tg mice had elevated proportions of CD4 + IL-4 + cells (Th2) and CD4 + CD25 + Foxp3 + cells (Treg) and a notable decrease in CD4 + IL-17 + cells (Th17).ConclusionOur results show that overexpressed SMILE attenuates the symptoms of OA, by increasing AMPK signaling and decreasing STAT3, thus reducing the levels of inflammatory immune cells.

Better accuracy of robotic-assisted total knee arthroplasty compared to conventional technique in patients with failed high tibial osteotomy.

This study aimed to compare the clinical outcomes, mechanical axis, component positioning, leg length discrepancy (LLD), and polyethylene liner thickness between robotic-assisted total knee arthroplasty (TKA) and conventional TKA in patients with failed high tibial osteotomy (HTO). A total of 30 patients (30 knees) with failed HTO who underwent TKA using a robot-assisted system between June 2020 and December 2023 were included in this study (robotic group). Additionally, 60 patients (60 knees) with failed HTO who underwent conventional TKA were included as controls (conventional group). Propensity score matching was performed using a 2:1 ratio between the matched participants. The mean follow-up period was 2.1 years in the robotic group and 2.2 years in the conventional group. Clinical evaluations were performed using the Knee Society Score (KSS) rating system. Mechanical axis, component coronal and sagittal positioning, and LLD were evaluated using postoperative radiographs. The thickness of the polyethylene liner was also determined. The mean error values and outliers were calculated and compared between the two groups to determine the accuracy of the mechanical axis, postoperative component positioning, and LLD. The postoperative KSSs in the robotic and conventional groups were not statistically different. The robotic group achieved better accuracy than the conventional group in terms of postoperative mean mechanical axis (1.7° vs. 2.4°, p < 0.05), femur coronal inclination (90.0° vs. 91.6°, p < 0.05), tibial coronal inclination (90.3° vs. 91.3°, p < 0.05), tibial sagittal inclination (90.5° vs. 91.4°, p < 0.05), and LLD (2.2 vs. 7.0 mm, p < 0.05). A significant difference in polyethylene liner thickness was observed between the two groups (p < 0.05). Robotic-assisted TKA showed improved mechanical axis, higher accuracy of component positioning and polyethylene liner thickness, and reduced LLD compared with those of conventional TKA in patients with failed HTO. Further studies with a larger sample size and long-term follow-up are warranted to ascertain whether the accuracy of robotic-assisted TKA can translate into better clinical outcomes and patient satisfaction.

Is intercalary frozen autograft augmented with intramedullary cement and bridging plates fixation a durable reconstruction?

AimsWe analysed the survival, complications, and function of frozen autograft augmented with intramedullary cement and bridging plates fixation for intercalary bone defect reconstruction in primary bone sarcomas.Patients and MethodsA retrospective cohort study was conducted on 72 patients with primary bone sarcomas (34 males, 38 females) between January 2016 and June 2023. The average age was 22.0 ± 13.6 years (6 to 61 years) and the pathological type included osteosarcoma (55), followed by adamantinoma (5), Ewing’s sarcoma (4), undifferentiated pleomorphic sarcoma (4), chondrosarcoma (3), and malignant tenosynovial giant cell tumor (1). The oncological outcomes included local control, metastasis, progression-free survival and overall survival. The functional outcomes were evaluated by the Musculoskeletal Tumor Society Score (MSTS-93), the Toronto Extremity Salvage Score (TESS), and the motion of the joint.ResultsThe mean follow-up time was 50.0 ± 27.4 months (12 to 99 months). 10 patients died of the disease, 9 patients were alive with disease and 53 patients were alive with no evidence of disease. The average 5-year overall survival of autograft was 85.8% (95% CI, 72.1-93.1%). The average MSTS-93 score was 96% ( 67–100%) and the average TESS score was 98% (74–100%). Twenty-four patients (33.3%) had at least one complication in the follow-up period. The most common complications were nonunion (9.7%, 7/72) and local recurrence (9.7%, 7/72), followed by leg length discrepancy (6.9%, 5/72), infection (5.6%, 4/72), implant failure (4.2%, 3/72), delayed union (2.8%, 2/72), and graft fractures (1.4%, 1/72). Tumor site was an independent risk factor for bone nonunion (OR, 22.23; p = 0.006).ConclusionsWe presented a large technique series for preventing autograft-related complications (especially for autograft fractures) of intercalary frozen autograft reconstruction. This method showed promising functional outcomes and provided durable reconstruction.Level of evidencelevel IV therapeutic study.

A good index surgery for congenital pseudarthrosis of the tibia minimizes complications following surgery.

Congenital pseudarthrosis of the tibia (CPT) has traditionally been a difficult condition to treat, with high complication rates, including nonunion, refractures, malalignment, and leg length discrepancy. Surgical approaches to treatment of CPT include intramedullary rodding, external fixation, combined intramedullary rodding and external fixation, vascularized fibular graft, and most recently cross-union. The current study aims to compare the outcomes and complication rates of cross-union versus other surgical approaches as an index surgery for the management of CPT. Our hypothesis was that a good index surgery for CPT achieves union and minimizes complications such as refractures and limb length discrepancy. A multicentre study was conducted involving two institutions in Singapore and China. All patients with CPT who were surgically managed between January 2009 and December 2021 were included. The patients were divided based on their index surgery. Group 1 included patients who underwent excision of hamartoma, cross-union of the tibia and fibula, autogenic iliac bone grafting, and internal fixation for their index surgery. Group 2 included patients who underwent all other surgical procedures for their index surgery, including excision of hamartoma, intramedullary rodding, and/or external fixation, without cross-union of the tibia and fibula. Comparisons of the rates of union, refracture, limb length discrepancy, reoperations, and other complications were performed between the two groups. A total of 36 patients were included in the study. Group 1 comprised 13 patients, while Group 2 comprised 23 patients. The mean age at index surgery was four years (1 to 13). The mean duration of follow-up was 4.85 years (1.75 to 14). All patients in Group 1 achieved bony union at a mean of three months (1.5 to 4), but ten of 23 patients in Group 2 had nonunion of the pseudarthrosis (p = 0.006). None of the patients in Group 1 had a refracture, while seven of 13 patients who achieved bony union in Group 2 suffered a refracture (p = 0.005). None of the patients in Group 1 had a limb length discrepancy of more than 2 cm, while ten of 23 patients in Group 2 have a limb length discrepancy of more than 2 cm (p = 0.006). In Group 1, four of 13 patients had a complication, while 16 of 23 patients in Group 2 had a complication (p = 0.004). Excluding removal of implants, four of 13 patients in Group 1 had to undergo additional surgery, while 18 of 23 patients in Group 2 had to undergo additional surgery following the index surgery (p = 0.011). A good index surgery of excision of hamartoma, cross-union of the tibia and fibula, autogenic iliac bone grafting, and internal fixation for CPT achieves union and minimizes complications such as refractures, limb length discrepancy, and need for additional surgeries.