Effects of differences in dose and frequency of teriparatide on bone structure in Proximal Femur. - Analysis by DXA-based 3D-modeling (3D-SHAPER Software) -TRIPLE-BONE study (The effects of TeRIParatide preparation on bone mineraL density increase and BONE structure).

Trends toward more favorable improvement of the cortical bone parameters by once-weekly (56.5 µg once a week) and twice-weekly teriparatide (28.2 µg twice a week), and that of the trabecular bone parameters by once-daily (1/D) teriparatide (20 µg/day once a day) were shown. PURPOSE: To examine the effects of differences in the amount of teriparatide (TPTD) per administration and its dosing frequency on the bone structure in the proximal femur by dual-energy X-ray absorptiometry (DXA)-based 3D-modeling (3D-SHAPER software). METHODS: This was a multicenter retrospective study. Patients aged 50 years or older with primary osteoporosis who continuously received once-/twice-weekly (1・2/W, n = 60) or 1/D TPTD (n = 14) administration for at least one year were included in the study. Measurement regions included the femoral neck (FN), trochanter (TR), femoral shaft (FS), and total proximal hip (TH). Concurrently, the bone mineral density (BMD) and Trabecular Bone Score (TBS) were measured. RESULTS: The cross-sectional area, cross-sectional moment of inertia, and section modulus in the FS were significantly improved in the 1・2/W TPTD group, as compared to the 1/D TPTD group. However, significant improvement of the cortical thickness and buckling ratio in the FN was observed in the 1/D TPTD group, as compared to the 1・2/W TPTD group. Trabecular BMD values in the FS and TH were significantly increased in the 1/D TPTD group, as compared to the 1・2/W TPTD group, while the cortical BMD values in the TR, FS, and TH were significantly increased in the 1・2/W TPTD group, as compared to the 1/D TPTD group. CONCLUSION: Trends toward more favorable improvement of the cortical bone by 1・2/W TPTD and that of the trabecular bones by 1/D TPTD were observed.

In vitro and in vivo dissolution of biocompatible S59 glass scaffolds.

Fabrication of porous tissue-engineering scaffolds from bioactive glasses (BAG) is complicated by the tendency of BAG compositions to crystallize in thermal treatments during scaffold manufacture. Here, experimental biocompatible glass S59 (SiO2 59.7 wt%, Na2O 25.5 wt%, CaO 11.0 wt%, P2O5 2.5 wt%, B2O3 1.3 wt%), known to be resistant to crystallization, was used in sintering of glass granules (300-500 µm) into porous scaffolds. The dissolution behavior of the scaffolds was then studied in vivo in rabbit femurs and under continuous flow conditions in vitro (14 days in vitro/56 days in vivo). The scaffolds were osteoconductive in vivo, as bone could grow into the scaffold structure. Still, the scaffolds could not induce sufficiently rapid bone ingrowth to replace the strength lost due to dissolution. The scaffolds lost their structure and strength as the scaffold necks dissolved. In vitro, S59 dissolved congruently throughout the 14-day experiments, resulting in only a slight reaction layer formation. Manufacturing BAG scaffolds from S59 that retain their amorphous structure was thus possible. The relatively rapid and stable dissolution of the scaffold implies that the glass S59 may have the potential to be used in composite implants providing initial strength and stable, predictable release of ions over longer exposure times.

Comparative Outcomes and Failure Rates of Total Femur Replacement in Oncologic and Nononcologic Indications: A Systematic Review and Meta-analysis.

BACKGROUND: Total femur replacement (TFR) has become increasingly significant as a salvage procedure for both oncologic reconstruction and complex nononcologic conditions such as revision arthroplasty. Despite its effectiveness in limb salvage, TFR is associated with high complication and failure rates, which vary depending on the underlying indication. METHODS: This systematic review and meta-analysis adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A comprehensive search of MEDLINE, EMBASE, Web of Science, and Cumulative Index to Nursing and Allied Health Literature databases was conducted, focusing on studies that reported outcomes of TFR in oncologic and nononcologic cases. Primary outcomes included failure mode and rates according to the Henderson classification, functional outcomes scores, and mobility status. Data were analyzed using random-effects models and generalized linear mixed models. RESULTS: A total of 35 studies involving 1,002 patients were included. The majority of TFRs were performed for oncologic reasons (63.7%). The mean Musculoskeletal Tumor Society (MSTS) score was 66%, with a limb salvage rate of 89%. The meta-analysis revealed a combined failure rate of 34%. For type 4 failures (infection), nononcologic patients exhibited a significantly higher rate at 18% (95% confidence interval [CI], 12%-26%, I2 = 46%, p < 0.01) compared with 8% in oncologic patients (95% CI, 6%-12%, I2 = 0%). Regarding combined types 1 to 4 failures, oncologic patients had a rate of 20% (95% CI, 25%-52%, I2 = 60%), whereas nononcologic patients faced a higher rate of 37% (95% CI, 12%-26%, I2 = 63%) (p < 0.05), indicating a significant difference. There were no significant differences in the MSTS score. In addition, there were no notable differences when comparing failure modes 1, 2, and 3 independently. Mobility analysis showed that approximately 70% of patients required walking aids after surgery. CONCLUSION: TFR offers a valuable limb salvage option in both oncologic and nononcologic scenarios, despite its high failure rates. Although functional outcomes were similar between groups, the higher failure rate in nononcologic cases and the poor overall quality of evidence warrant further comprehensive assessments into predictors of outcomes to optimize results. LEVEL OF EVIDENCE: Level III. See Instructions for Authors for a complete description of levels of evidence.

Conventional vs. endoscopic-assisted curettage of benign bone tumours. An experimental study.

BACKGROUND: This experimental study aimed at directly comparing conventional and endoscopic-assisted curettage towards (1) amount of residual tumour tissue (RTT) and (2) differences between techniques regarding surgical time and surgeons' experience level. METHODS: Three orthopaedic surgeons (trainee, consultant, senior consultant) performed both conventional (4x each) and endoscopic-assisted curettages (4x each) on specifically prepared cortical-soft cancellous femur and tibia sawbone models. "Tumours" consisted of radio-opaque polyurethane-based foam injected into prepared holes. Pre- and postinterventional CT-scans were carried out and RTT assessed on CT-scans. For statistical analyses, percentage of RTT in relation to total lesion's volume was used. T-tests, Wilcoxon rank-sum tests, and Kruskal-Wallis tests were applied to assess differences between surgeons and surgical techniques regarding RTT and timing. RESULTS: Median overall RTT was 1% (IQR 1 - 4%). Endoscopic-assisted curettage was associated with lower amount of RTT (median, 1%, IQR 0 - 5%) compared to conventional curettage (median, 4%, IQR 0 - 15%, p = 0.024). Mean surgical time was prolonged with endoscopic-assisted (9.2 ± 2.9 min) versus conventional curettage (5.9 ± 2.0 min; p = 0.004). No significant difference in RTT amount (p = 0.571) or curetting time (p = 0.251) depending on surgeons' experience level was found. CONCLUSIONS: Endoscopic-assisted curettage appears superior to conventional curettage regarding complete tissue removal, yet at expenses of prolonged curetting time. In clinical practice, this procedure may be reserved for cases at high risk of recurrence (e.g. anatomy, histology).

Hidden blood loss and its risk factors after hip reconstruction in children.

OBJECTIVE: There were few reports in the literature regarding hidden blood loss following surgery for developmental dysplasia of the hip in children. This study aimed to evaluate the volume of hidden blood loss and its risk factors among children undergoing hip reconstruction for developmental dysplasia of the hip. METHODS: A retrospective analysis of clinical data from 42 patients (58 hips), who underwent Pemberton and femoral osteotomies between March 2020 and March 2023, was conducted. Serial complete blood count assays were conducted on the day of admission and four days post-surgery. Preoperative and postoperative hematocrit levels were documented to calculate hidden blood loss utilizing the Gross formula. Pearson and Spearman correlation analyses, along with multivariable linear regression, were employed to ascertain associations between patient characteristics and hidden blood loss. RESULTS: The mean hidden blood loss was recorded as 283.06 ± 271.05 mL, constituting 70.22% of the total blood loss. Multiple linear regression analysis identified weight and surgical duration as independent risk factors contributing to hidden blood loss. CONCLUSIONS: A relevant amount of postoperative hidden blood loss occurs after Pemberton osteotomy and femoral osteotomy for developmental dysplasia of the hip. Surgeons should be aware that patients who require blood transfusions and have longer surgical durations are at a higher risk of developing more hidden blood loss. Therefore, attention should be given to hidden blood loss to ensure patient safety during the perioperative period for those undergoing Pemberton and femoral osteotomies. LEVEL OF EVIDENCE: IV.

Changes in femoral anteversion after intramedullary nailing for pediatric femoral shaft fracture: a multicenter study.

BACKGROUND: The rotational change after using a flexible intramedullary (IM) nail for femoral shaft fractures has been a concern for many surgeons. Recently, a statistical shape model (SSM) was developed for the three-dimensional reconstruction of the femur from two-dimensional plain radiographs. In this study, we measured postoperative femoral anteversion (FAV) in patients diagnosed with femoral shaft fractures who were treated with flexible IM nails and investigated age-related changes in FAV using the SSM. METHODS: This study used radiographic data collected from six regional tertiary centers specializing in pediatric trauma in South Korea. Patients diagnosed with femoral shaft fractures between September 2002 and June 2020 and patients aged < 18 years with at least two anteroposterior (AP) and lateral (LAT) femur plain radiographs obtained at least three months apart were included. A linear mixed model (LMM) was used for statistical analysis. RESULTS: Overall, 72 patients were included in the study. The average patient age was 7.6 years and the average follow-up duration was 6.8 years. The average FAV of immediate postoperative images was 27.5 ± 11.5°. Out of 72 patients, 52 patients (72.2%) showed immediate postoperative FAV greater than 20°. The average FAV in patients with initial FAV > 20° was 32.74°, and the LMM showed that FAV decreased by 2.5° (p = 0.0001) with each 1-year increase from the time of initial trauma. CONCLUSIONS: This study explored changes in FAV after femoral shaft fracture using a newly developed technology that allows 3D reconstruction from uncalibrated 2D images. There was a pattern of change on the rotation of the femur after initial fixation, with a 2.5° decrease of FAV per year.

Factors leading to falls in transfemoral prosthesis users: a case series of prosthesis-side stumble recovery responses.

BACKGROUND: Falls due to stumbling are prevalent for transfemoral prosthesis users and may lead to increased injury risk. This preliminary case series analyzes the transfemoral prosthesis user stumble recovery response to highlight key deficits in current commercially-available prostheses and proposes potential interventions to improve recovery outcomes. METHODS: Six transfemoral prosthesis users were perturbed on their prosthetic limb at least three times while walking on a treadmill using obstacle perturbations in early, mid and late swing. Kinematic data were collected to characterize the response, while fall rate and key kinematic recovery metrics were used to assess the quality of recovery and highlight functional deficits in current commercially-available prostheses. RESULTS: Across all participants, 13 (54%) of the 24 trials resulted in a fall (defined as > 50% body-weight support) with all but one participant (83%) falling at least once and two participants (33%) falling every time. In contrast, in a previous study of seven young, unimpaired, non-prosthesis users using the same experimental apparatus, no falls occurred across 190 trials. For the transfemoral prosthesis users, early swing had the highest rate of falling at 64%, followed by mid-swing at 57%, and then late swing at 33%. The trend in falls was mirrored by the kinematic recovery metrics (peak trunk angle, peak trunk angular velocity, forward reach of the perturbed limb, and knee angle at ground contact). In early swing all four metrics were deficient compared to non-prosthesis user controls. In mid swing, all but trunk angular velocity were deficient. In late swing only forward reach was deficient. CONCLUSION: Based on the stumble recovery responses, four potential deficiencies were identified in the response of the knee prostheses: (1) insufficient resistance to stance knee flexion upon ground contact; (2) insufficient swing extension after a perturbation; (3) difficulty initiating swing flexion following a perturbation; and (4) excessive impedance against swing flexion in early swing preventing the potential utilization of the elevating strategy. Each of these issues can potentially be addressed by mechanical or mechatronic changes to prosthetic design to improve quality of recovery and reduce the likelihood a fall.

Changes in the anteroposterior position of the femur relative to the tibia impact patient satisfaction in total knee arthroplasty.

BACKGROUND: In this study, we aimed to investigate the preoperative and postoperative anteroposterior position (AP) of the femur relative to the tibia in total knee arthroplasty (TKA) and assess the influence of change in the AP position on clinical outcomes. METHODS: We evaluated 49 knees that underwent bi-cruciate-substituted TKA using a navigation system. The preoperative and postoperative AP position of the femur relative to the tibia at maximum extension, 15°, 30°, 45°, 60°, 90°, 105°, and 120° and maximum flexion angles were calculated. The 2011 Knee Society Score was evaluated preoperatively and 1 year postoperatively. The Wilcoxon signed rank and Spearman's rank correlation tests were performed, with statistical significance set at P < 0.05. RESULTS: The postoperative AP position was significantly correlated with the preoperative AP position at each measured angle. The postoperative AP positions were statistically more anterior than those preoperatively. Furthermore, the changes in the AP position after TKA negatively correlated with the symptom (P = 0.027 at 30°, P = 0.0018 at 45°, P = 0.0003 at 60°, P = 0.01 at 90°, and P = 0.028 at 105°) and patient satisfaction (P = 0.018 at 60° and P = 0.009 at 90°) scores at 1 year postoperatively. CONCLUSION: The postoperative AP position of the femur relative to the tibia was strongly influenced by the preoperative those in TKA. Postoperative anterior deviation of the femur relative to the tibia from mid-flexion to deep flexion could worsen clinical outcomes.

Fabricating vascularized, anatomically accurate bone grafts using 3D bioprinted sectional bone modules, in-situ angiogenesis, BMP-2 controlled release, and bioassembly.

Bone grafting is the most common treatment for repairing bone defects. However, current bone grafting methods have several drawbacks. Bone tissue engineering emerges as a promising solution to these problems. An ideal engineered bone graft should exhibit high mechanical strength, osteogenic properties, and pre-vascularization. Both top-down (using bulk scaffold) and bottom-up (using granular modules) approaches face challenges in fulfilling these requirements. In this paper, we propose a novel sectional modular bone approach to construct osteogenic, pre-vascularized bone grafts in anatomical shapes. We 3D-printed a series of rigid, thin, sectional, porous scaffolds from a biodegradable polymer, tailored to the dimensions of a femur bone shaft. These thin sectional modules promote efficient nutrition and waste removal due to a shorter diffusion distance. The modules were pre-vascularized viain-situangiogenesis, achieved through endothelial cell sprouting from the scaffold struts. Angiogenesis was further enhanced through co-culture with bioprinted fibroblast microtissues, which secreted pre-angiogenic growth factors. Sectional modules were assembled around a porous rod incorporated with Bone Morphogenetic Protein-2 (BMP-2), which released over 3 weeks, demonstrating sustained osteogenic activity. The assembled scaffold, in the anatomical shape of a human femur shaft, was pre-vascularized, osteogenic, and possessed high mechanical strength, supporting 12 times the average body weight. The feasibility of implanting the assembled bone graft was demonstrated using a 3D-printed femur bone defect model. Our method provides a novel modular engineering approach for regenerating tissues that require high mechanical strength and vascularization.

Effects of three-dimensional femur and tibia postures on the parameters of standing long-leg radiographs for osteoarthritic knees in elderly female subjects.

BACKGROUND: Long-leg frontal radiographs of the lower extremities are used to assess knee osteoarthritis. Given the three-dimensional (3D) nature of alignment changes in osteoarthritis, postural alterations in the femur and tibia extend beyond the coronal plane (in-plane) to include the transverse and sagittal planes (out-of-plane). This study investigates the impact of these out-of-plane factors on in-plane knee alignment parameters observed in frontal radiographs. METHODS: A total of 97 osteoarthritic knees in women were examined. Using a 3D-to-two-dimensional (2D) image matching technique, we evaluated the 3D postures of the femur and tibia in the standing position as viewed from frontal radiographs in the world coordinate system. Statistical analyses were conducted to explore associations between these 3D postures and 2D alignment parameters obtained from frontal radiographs under identical conditions. FINDINGS: The femur exhibited a medial inclination of 2.7°, a posterior inclination of 3.9°, and an internal rotation of 4.2°, whereas the tibia showed a lateral inclination of 6.4°, an anterior inclination of 6.7°, and an internal rotation of 6.7°. Both coronal and rotational postures of femur and tibia influenced the hip-knee-ankle angle, mechanical axis percentage, and medial proximal tibial angle. However, only coronal factors of tibia impacted tibial joint line obliquity relative to the floor. INTERPRETATION: Attention should be paid to the potential impact of the out-of-plane postures of the femur and tibia on parameters assessed in plain frontal radiographs of the lower extremities.

Critical Examination of Methods to Determine Tibiofemoral Kinematics and Tibial Contact Kinematics Based on Analysis of Fluoroscopic Images.

Goals of knee replacement surgery are to restore function and maximize implant longevity. To determine how well these goals are satisfied, tibial femoral kinematics and tibial contact kinematics are of interest. Tibiofemoral kinematics, which characterize function, is movement between the tibia and femur whereas tibial contact kinematics, which is relevant to implant wear, is movement of the location of contact by the femoral implant on the tibial articular surface. The purposes of this review article are to describe and critique relevant methods to guide correct implementation. For tibiofemoral kinematics, methods are categorized as those which determine (1) relative planar motions and (2) relative three-dimensional (3D) motions. Planar motions are determined by first finding anterior-posterior (A-P) positions of each femoral condyle relative to the tibia and tracking these positions during flexion. Of the lowest point (LP) and flexion facet center (FFC) methods, which are common, the lowest point method is preferred and the reasoning is explained. 3D motions are determined using the joint coordinate system (JCS) of Grood and Suntay. Previous applications of this JCS have resulted in motions which are largely in error due to "kinematic crosstalk." Requirements for minimizing kinematic crosstalk are outlined followed by an example, which demonstrates the method for identifying a JCS that minimizes kinematic crosstalk. Although kinematic crosstalk can be minimized, the need for a JCS to determine 3D motions is questionable based on anatomical constraints, which limit varus-valgus rotation and compression-distraction translation. Methods for analyzing tibial contact kinematics are summarized and validation of methods discussed.

Development and clinical validation of a deep learning-based knee CT image segmentation method for robotic-assisted total knee arthroplasty.

BACKGROUND: This study aimed to develop a novel deep convolutional neural network called Dual-path Double Attention Transformer (DDA-Transformer) designed to achieve precise and fast knee joint CT image segmentation and to validate it in robotic-assisted total knee arthroplasty (TKA). METHODS: The femoral, tibial, patellar, and fibular segmentation performance and speed were evaluated and the accuracy of component sizing, bone resection and alignment of the robotic-assisted TKA system constructed using this deep learning network was clinically validated. RESULTS: Overall, DDA-Transformer outperformed six other networks in terms of the Dice coefficient, intersection over union, average surface distance, and Hausdorff distance. DDA-Transformer exhibited significantly faster segmentation speeds than nnUnet, TransUnet and 3D-Unet (p < 0.01). Furthermore, the robotic-assisted TKA system outperforms the manual group in surgical accuracy. CONCLUSIONS: DDA-Transformer exhibited significantly improved accuracy and robustness in knee joint segmentation, and this convenient and stable knee joint CT image segmentation network significantly improved the accuracy of the TKA procedure.

Is still effective massive allograft reconstruction in parosteal osteosarcoma of the distal femur? Review of the literature and advantages of newer technologies.

PURPOSE: Parosteal Osteosarcoma is a well-differentiated, low-grade bone sarcoma. It most commonly occurs in the third decade of life, usually in the distal femur. This study aims to perform a literature review about the types of reconstructions reported and to analyze the results of an updated technique of resection using custom-made 3D-printed cutting guides. METHODS: We perform a systematic literature review about parosteal osteosarcoma, evaluating treatments, margins, local recurrence, complications, and functional results when available. We also report a case treated in our Center with a revisited technique introducing custom-made 3D-printed cutting guides. RESULTS: We analyzed 12 studies with a total of 151 patients. The distal femur was the most frequently reported site (81.5%). After distal femur resection, reconstruction was performed with graft in most cases (48%), followed by prosthetic reconstruction (40%). Margins were wide in 85.5% of cases. The total incidence of local recurrence was 11%. Functional results were excellent in all cases, with a mean MSTS score of 86%. In our case, with the help of the jigs, the surgical technique was relatively easy, graft fusion excellent and fast, margins wide, and functional results excellent. CONCLUSIONS: In the literature, the most commonly used type of reconstruction after resection is biological with graft. Indeed, despite the increasing number of prosthetic reconstructions, the historical diaphysometaphyseal hemiresection and graft is still indicated in parosteal osteosarcoma of the distal femur. New technologies, such as the jigs we used, allow significant advantages during the procedure: reduce the resection and graft preparation time, allow a better match between components, and help to obtain safer margins, sparing as much bone as possible.

The Principles of Hip Joint Preservation.

The 3 primary factors involved with preservation of the hip joint are femoroacetabular impingement (FAI), hip dysplasia, and femoral torsion abnormalities. Each of these factors affects the health of the acetabular labrum and femoroacetabular cartilage. The appropriate surgical treatments for each of these factors include arthroscopic or open femoroplasty or acetabuloplasty for FAI, periacetabular osteotomy (PAO) for acetabular dysplasia, and de-rotational femoral osteotomy for femoral torsion abnormalities. When evaluating patients with prearthritic hip conditions, orthopaedic surgeons should be aware of the various factors involved in hip joint preservation and, if surgery is indicated, surgeons should be sure to address all factors that need surgical treatment rather than focusing on the most obvious issue or injury (e.g., a labral tear). The purpose of this infographic is to illustrate the importance of the factors involved in hip joint preservation and the appropriate treatments for pathology in any of these factors.

[Medium- and long-term effectiveness of hip revision with SL-PLUS MIA stem in patients with Paprosky type â - â ¢ femoral bone defect].

Objective: To investigate the medium- and long-term effectiveness of hip revision with SL-PLUS MIA stem in patients with Paprosky typeⅠ-Ⅲ femoral bone defect. Methods: Between June 2012 and December 2018, 44 patients with Paprosky typeⅠ-Ⅲ femoral bone defect received hip revision using SL-PLUS MIA stem. There were 28 males and 16 females, with an average age of 57.7 years (range, 31-76 years). Indications for revision comprised aseptic loosening (27 cases) and periprosthetic joint infection (17 cases). The Harris hip scores were 54 (48, 60) and 43 (37, 52) in patients with aseptic loosening and periprosthetic joint infection, respectively. The preoperative femoral bone defects were identified as Paprosky type Ⅰ in 32 cases, type Ⅱ in 9 cases, type ⅢA in 2 cases, and type ⅢB in 1 case. Operation time and intraoperative blood transfusion volume were recorded. During follow-up after operation, the hip joint function were evaluated by Harris hip score and X-ray films, the femoral stem survival was analyzed, and the surgical related complications were recorded. Results: The operation time of infected patients was 95-215 minutes, with an average of 125.0 minutes. The intraoperative blood transfusion volume was 400-1 800 mL, with an average of 790.0 mL. The operation time of patients with aseptic loosening was 70-200 minutes, with an average of 121.0 minutes. The intraoperative blood transfusion volume was 400-1 400 mL, with an average of 721.7 mL. All patients were followed up 5.3-10.0 years (mean, 7.4 years). At last follow-up, the Harris hip scores were 88 (85, 90) and 85 (80, 88) in patients with aseptic loosening and periprosthetic joint infection, respectively, both of which were significantly higher than those before operation ( P<0.05). Radiological examination results showed that the distal end of the newly implanted femoral stem did not cross the distal end of the original prosthesis in 25 cases, and all femoral stems obtained bone fixation. Two cases experienced femoral stem subsidence and 1 case had a translucent line on the lateral side of the proximal femoral stem. When aseptic loosening was defined as the end event, the 10-year survival rate of the SL-PLUS MIA stem was 100%. When treatment failure due to any reason was defined as the end event, the survival time of the prosthesis was (111.70±3.66) months, and the 7-year survival rate was 95.5%. The 7-year survival rates were 94.1% and 96.3% in patients with aseptic loosening and periprosthetic joint infection, respectively. The incidence of postoperative complications was 9.1% (4/44), among which the prosthesis related complications were 4.5% (2/44), 1 case of dislocation and 1 case of infection recurrence. Conclusion: Hip revision with SL-PLUS MIA stem has the advantages of simple operation and few postoperative complications in the patients with Paprosky type Ⅰ-Ⅲ femoral bone defect, and the medium- and long-term effectiveness is reliable.

Management of infected bone defects of the femoral shaft by Masquelet technique: sequential internal fixation and nail with plate augmentation.

BACKGROUND: To evaluate the effectiveness of a sequential internal fixation strategy and intramedullary nailing with plate augmentation (IMN/PA) for bone reconstruction in the management of infected femoral shaft defects using the Masquelet technique. METHODS: We performed a retrospective descriptive cohort study of 21 patients (mean age, 36.4 years) with infected bone defects of the femoral shaft treated by the Masquelet technique with a minimum follow-up of 18 months after second stage. After aggressive debridement, temporary stabilisation (T1) was achieved by an antibiotic-loaded bone cement spacer and internal fixation with a bone cement-coated locking plate. At second stage (T2), the spacer and the locking plate were removed following re-debridement, and IMN/PA was used as definitive fixation together with bone grafting. We evaluated the following clinical outcomes: infection recurrence, bone union time, complications, and the affected limb's knee joint function. RESULTS: The median and quartiles of bone defect length was 7 (4.75-9.5) cm. Four patients required iterative debridement for infection recurrence after T1. The median of interval between T1 and T2 was 10 (9-19) weeks. At a median follow-up of 22 (20-27.5) months, none of the patients experienced recurrence of infection. Bone union was achieved at 7 (6-8.5) months in all patients, with one patient experiencing delayed union at the distal end of bone defect due to screws loosening. At the last follow-up, the median of flexion ROM of the knee joint was 120 (105-120.0)°. CONCLUSIONS: For infected femoral shaft bone defects treated by the Masquelet technique, sequential internal fixation and IMN/PA for the reconstruction can provide excellent mechanical stability, which is beneficial for early functional exercise and bone union, and does not increase the rate of infection recurrence.

Simultaneous correction of leg length discrepancy and angular deformity of the distal femur with retrograde Precice nails: a retrospective analysis of 45 patients.

BACKGROUND AND PURPOSE: Magnetically controlled motorized intramedullary lengthening nails (ILNs) can be employed for simultaneous correction of angular deformities of the distal femur and leg length discrepancy. This spares typical complications of external fixators but requires precise preoperative planning and exact intraoperative execution. To date, its results are insufficiently reported. We aimed to elucidate the following questions: (i) Is acute angular deformity correction and gradual femoral lengthening via a retrograde ILN a reliable and precise treatment option? (ii) What are the most common complications of treatment? METHODS: Acute angular deformity correction and subsequent gradual lengthening of the distal femur with retrograde ILN was retrospectively analyzed in 45 patients (median patient age: 15 years, interquartile range [IQR] 13-19 and median follow-up: 40 months, IQR 31-50). Outcome parameters were accuracy, precision, reliability, bone healing, and complications of treatment. RESULTS: The median distraction was 46 mm (IQR 29-49), median distraction and consolidation index 0.9 mm/day (IQR 0.7-1.0) and 29 days/cm (IQR 24-43), respectively. The median preoperative mechanical axis deviation (MAD) was 30 mm (IQR 23-39) in the varus cohort and -25 mm (IQR -29 to -15) in the valgus cohort and reduced to a mean of 8 mm (standard deviation [SD] 8) and -3 (SD 10), respectively. Accuracy, precision, and reliability of lengthening were 94%, 95% and 96%, respectively. Accuracy and precision of deformity correction were 92% and 89%, respectively. In total, 40/45 of patients achieved distraction with a difference of less than 1 cm from the initial plan and a postoperative MAD ranging from -10 mm to +15 mm. In 13/45 patients unplanned additional surgeries were conducted to achieve treatment goal with nonunion being the most frequent (4/45) and knee subluxation (3/45) the most severe complication. CONCLUSION: Acute deformity correction and subsequent lengthening of the distal femur with retrograde ILN is a reliable and accurate treatment achieving treatment goal in 89% but unplanned additional surgeries in 29% of patients should be anticipated.

Effects of bone surface topography and chemistry on macrophage polarization.

Surface structure plays a crucial role in determining cell behavior on biomaterials, influencing cell adhesion, proliferation, differentiation, as well as immune cells and macrophage polarization. While grooves and ridges stimulate M2 polarization and pits and bumps promote M1 polarization, these structures do not accurately mimic the real bone surface. Consequently, the impact of mimicking bone surface topography on macrophage polarization remains unknown. Understanding the synergistic sequential roles of M1 and M2 macrophages in osteoimmunomodulation is crucial for effective bone tissue engineering. Thus, exploring the impact of bone surface microstructure mimicking biomaterials on macrophage polarization is critical. In this study, we aimed to sequentially activate M1 and M2 macrophages using Poly-L-Lactic acid (PLA) membranes with bone surface topographical features mimicked through the soft lithography technique. To mimic the bone surface topography, a bovine femur was used as a model surface, and the membranes were further modified with collagen type-I and hydroxyapatite to mimic the bone surface microenvironment. To determine the effect of these biomaterials on macrophage polarization, we conducted experimental analysis that contained estimating cytokine release profiles and characterizing cell morphology. Our results demonstrated the potential of the hydroxyapatite-deposited bone surface-mimicked PLA membranes to trigger sequential and synergistic M1 and M2 macrophage polarizations, suggesting their ability to achieve osteoimmunomodulatory macrophage polarization for bone tissue engineering applications. Although further experimental studies are required to completely investigate the osteoimmunomodulatory effects of these biomaterials, our results provide valuable insights into the potential advantages of biomaterials that mimic the complex microenvironment of bone surfaces.

Evaluation of the Influence of Hypolipidemic Medication on Albino Wistar Rats' Bone Tissue by NMR Diffusiometry.

Introduction: The ongoing concern of the medical profession regarding chronic medication is related to increasing patient adherence and compliance to treatment and reducing medication side effects. In this respect, drugs represented by fixed-dose combinations of active substances within the same tablet have emerged. Such a principle can be extrapolated by following the potential beneficial effects that a chronic medication can have on chronic pathologies affecting different systems. Materials and Methods: The study included 48 female Albino Wistar rats, aged 16-18 months, which were divided into two groups: ovariectomized and non-ovariectomized rats. One batch of 12 non-ovariectomized rats received no treatment, becoming a control batch (NOVX-M). The ovariectomized (OVX) group was divided into 3 batches of 12 rats each: no treatment, control (OVX-M), fenofibrate-treated (OVX-F) and statin-treated (OVX-S) rats. At 12 weeks after ovariectomy, a femoral fracture occurred in the right hind limb of all animals included in the experiment To reveal the changes, at intervals of 2, 4, 6 and 8 weeks post-fracture, the proximal part of the femur was evaluated by NMR diffusiometry, which allows random motion of proton molecules expressed by self-diffusion coefficients, D, thus allowing analysis of the size and complexity of microscopic order cavities within biological structures, such as pores inside bones. Results: The effects of hypolipidemic medication in the absence of estrogen were evidenced, proving the beneficial effect that fenofibrate can have in preserving healthy tissue exposed to osteoporotic risk during the menopausal period. The effects of lipid-lowering medication are also influenced by the duration of administration. Conclusions: Osteoporosis and heart disease are two chronic pathologies that affect mainly female population in the second half of life, and proving the dual therapeutic potential of lipid-lowering medication may also have positive effects by increasing adherence and compliance to treatment.