Femoral Canal Research Articles

Continuous peripheral nerve blocks for burn management: a retrospective study of outcomes and complications in 281 burn patients.

There is scarce literature regarding the use of continuous peripheral nerve blocks in acute burn patients, who may be at higher risk for catheter-related complications, including infection. We sought to describe our center's experience and infection rate with continuous perineural catheters in the setting of pain management for patients suffering from burns. A retrospective observational study was performed including all patients admitted to an American Burn Association-verified regional burn center between January 2018 and July 2023 who received a continuous peripheral nerve block for an acute burn injury. There were 281 patients in the study cohort who received 484 perineural catheters. The cohort was 52% men with a median age of 39 years (IQR 30-55). A catheter-associated infection, defined as a clinical diagnosis by the treating physicians requiring the need for treatment with antibiotics or surgical debridement, was identified in six perineural catheters (1.2%, 95% CI 0% to 2.2%) involving six different patients (2.1%, 95% CI 0% to 3.8%). The median total body surface area burned was 5% (IQR 2-9%) and 20% of patients had full-thickness burns. The most commonly used catheters were infraclavicular (49%), popliteal sciatic (29%), femoral (19%), and adductor canal (17%). One-third (33%) of patients did not require operating room debridement as the block provided sufficient analgesia for bedside debridement. The median duration of catheter use was 6 days (IQR 4-8). There were no documented cases of nerve injury or toxicity, vascular injury, or local anesthetic systemic toxicity. In our practice, continuous perineural catheters in the setting of acute burns are associated with an infection rate comparable to other surgical populations.

Reduced Graphene Oxide-Substituted Nanohydroxyapatite: Rejuvenating Bone-Nerve Crosstalk with Electrical Cues in a Fragility Fracture Rat Model under Hyperglycemia.

Diabetes has currently acquired the status of epidemic worldwide, and among its various pathological consequences like retinopathy and nephropathy, bone fragility fractures from diabetic osteopathy occurs in later stages and is equally destructive. Chronic hyperglycemia culminates into deteriorating microvasculature and quality of bone, making it prone to fractures. Among these, hip fractures are most common, especially in older diabetic patients apart from underlying neuropathy. Our study is an attempt to ameliorate hip fragility fracture and nerve trauma with electrical stimulation as an interface in a chronic diabetic rat model. We have fabricated reduced graphene oxide-substituted hydroxyapatite as an electroactive bone substitute and incorporated it into chitosan gelatin cryogels. The in situ reduction of graphene oxide during sintering of hydroxyapatite imparts higher potential to the fabricated composite in dealing with problem at question. The cryogels depicted optimum in vitro biocompatibility and enhanced mineralization after ectopic subcutaneous implantation in rats. The therapeutic potency of composite cryogels was evaluated in a hip fracture model with compression to the sciatic nerve in diabetic rats, mimicking the severe clinical trauma. The presence of cryogels in the femoral neck canal coupled with electrical stimulation and biochemical factors significantly improved bone regeneration in diabetic rats as depicted with microcomputed tomography analysis and histology images. The application of electrical stimulation also ameliorated the nerve trauma observed with 70% improvement in electrophysiological parameters such as the compound muscle action potential with combinatorial therapy. We therefore report the successful implication of a multitarget therapy in a chronic diabetic rat model unraveling the bone-nerve crosstalk with electroactive smart cryogels.

Comparative study of total hip arthroplasty with and without femoral osteotomy in Crowe Ⅳ developmental dysplasia of the hip

To compare the clinical effects of total hip arthroplasty(THA) with and without femoral osteotomy in Crowe Ⅳ developmental hip dislocation(DDH). The data on 46 patients who underwent THA for unilateral Crowe Ⅳ DDH between 2012 and 2017 were analyzed retrospectively. They were divided into two groups according to the different surgical methods. There were 24 patients in the osteotomy group, 3 males and 21 females, with an average age of (47.3±9.0) years old ranged from 34 to 57 years old;and 22 patients in the non-osteotomy group, 2 males and 20 females, with an average age of (51.6±8.3) years old ranged from 40 to 61 years old. The operative time, bleed loss, postoperative drainage volume, postoperative complications, ROM of hip, Harris hip score, limb length discrepancy(LLD), and radiological data were recorded. The femoral dislocation height and the implantation depth of sleeve were measured. All patients were followed up. The mean follow-up time was (3.8±1.2) years ranged from 2 to 6 years in the osteotomy group and (3.2±0.9) years ranged from 1 to 5 years in the non-osteotomy group. The operative time(136.8±18.9) min, bleed loss (709.8±89.4) ml, postoperative drainage volume(308.8±98.2) ml of osteotomy group were all significantly greater than those of non-osteotomy group(100.7±15.8)min, (516.5±103.3) ml, (245.3±79.3) ml (P<0.05). The Harris score at the latest follow up was significantly increased compared with preoperative score in two groups (P<0.05), but there was no significant difference between two groups (P>0.05). The LLD at last follow up was significantly increased compared with preoperative LLD in two groups, the LLD in non-osteotomy group(0.7±0.2) cm showed signifcant smaller than the two osteotomy group(1.2±0.4) cm. Between osteotomy and non-osteotomy groups, the preoperative range of motion of hip joint [(89.5±19.7) °vs (102.5±16.8) °], the preoperative height of dislocation of femoral head [(4.56±0.61) cm vs (3.10±0.73) cm], the proximal implant depth of S-ROM [(0.93±0.36) cm vs (1.67±0.28) cm] was significantly different (P<0.05). Eleven patients in the osteotomy group still had claudication, and 4 patients in the non-osteotomy group had mild claudication (P<0.05). In non-osteotomy group, 3 patients developed nerve injury (1 patient of sciatic nerve, 2 patients of femoral nerve) and 1 case developed periprosthetic fracture. In osteotomy group, 2 case of dislocation and 2 cases of periprosthetic fractures. Whether osteotomy or not can achieve satisfactory results for treating Crowe type Ⅳ DDH and significantly improve LLD. However, osteotomy is more complex and time-consuming, limb length difference is greater, and the incidence of claudication is higher. Furthermore, patients with smaller preoperative hip mobility, higher femoral dislocation, limb lengthening≥4 cm and severely narrow femoral proximal canals are prone to be peformed with subtrochanteric osteotomy.

Leg length discrepancy risk differs between fit-and-fill and taper wedge stems across Dorr types.

The comparison between the cementless taper wedge stem and fit-and-fill stem in total hip arthroplasty (THA) for various proximal femoral morphological types has not been thoroughly assessed. This study aimed to compare the risk of leg length discrepancy (LLD) ≥ 10mm between these two stem types in Dorr type A, B, and C femurs. From April 2015 through April 2021, we analyzed 1178 unilateral primary cementless THA procedures. We categorized all procedures into three groups: Dorr type A (N = 220, 18.7%), B (N = 875, 74.3%), and C (N = 83, 7.0%). Within each Dorr type, we compared the incidence and risk of postoperative LLD ≥ 10mm between the two stem types. The factors considered in the multivariate regression analyses included stem type, age, sex, body mass index, diagnosis, canal flare index, femoral cortical index and stem alignment. The taper wedge stem group had a higher overall incidence of LLD ≥ 10mm (12.8% vs. 7.4%, P = 0.012) and in Dorr type A femurs (22.2% vs. 7.6%, P = 0.014), compared with the fit-and-fill stem group. In multivariate analysis, the taper wedge stem exhibited an increased risk of LLD ≥ 10mm only in Dorr type A femurs (aOR: 3.449, 95% CI: 1.325-8.794). The incidence and risk of LLD ≥ 10mm were not different between the two stems in Dorr type B and C femurs. The taper wedge stem demonstrated an elevated risk of LLD ≥ 10mm in Dorr type A femurs compared with the fit-and-fill stem, necessitating meticulous preoperative templating and intraoperative femoral canal preparation.

Differences in Femoral Medullary Canal Dimensions in the USA and East Asian Populations

With emerging technologies and improved operative techniques, cementless total hip arthroplasty is becoming more popular and showing better results. The femoral prosthesis and intramedullary nail should precisely fit in the medullary canal to prevent micromotion and loosening. Most of the femoral prosthesis and nail designs are made from the data obtained from Caucasian femur and may not press fit if used in Asian populations. This study compares the femoral medullary canal diameter in American and Oriental populations at different bony levels. A total of 245 dry femora were collected which included 47 from United States, 77 from China, 44 from Japan, 50 from Korea and 27 from Taiwan, and plan radiographs were taken. Radiographs were digitized to measure the medullary canal width at 20% (lesser trochanter; LT), 35% (supra-isthmus; SI), 50% (mid-isthmus; MI), 65% and 80% of the total femur length. The results revealed significant differences in the medullary canal width between the US and East Asian Oriental populations. The medullary canal in the US population was significantly larger at the LT, SI, MI, and 65% but significantly smaller at 80% of the femoral shaft length compared to the East Asian populations. Among the East Asian populations, significant differences were obse4rved between the Chinese and Taiwanese populations as well as the Japanese and Taiwanese populations. The Taiwanese population had the smallest femoral medullary canal size among the east Asian populations. We conclude that there are significant differences in the femoral medullary width between the American and East Asian populations. These results will be useful for surgeons operating on the proximal or distal femur.

Inflammatory Marker Changes Following Total Knee Arthroplasty for Rheumatoid Arthritis with Vancomycin-loaded Calcium Sulfate Bone Filling.

Rheumatoid arthritis (RA) patients undergoing total knee arthroplasty (TKA) face infection risk. The study evaluates vancomycin-loaded calcium sulfate bone as infection prevention. Patients with RA treated with TKA who had their femoral canal filled using either vancomycin-loaded calcium sulfate bone (experimental group [n = 35]) or the patient's own excised autologous bone (control group [n = 30]) at the Qingdao University Affiliated Hospital, Qingdao, China from January 1, 2017, to March 1, 2023, were retrospectively enrolled in this study. An experienced surgeon used midvastus approach. Surgeries included disinfection, antibiotics, and femoral filling. The age, gender, body mass index (BMI), comorbidities, and intraoperative details were extracted from the patient's medical records. Preoperation and postoperation markers (C-reactive protein [CRP], erythrocyte sedimentation rate [ESR]), pain scale (Visual Analog Scale [VAS]), infection rate, and Knee Society Score (KSS) were collected. Groups matched in age, gender, and BMI. No preoperative inflammatory marker differences were observed. However, compared to the control group, the postoperative inflammatory markers were significantly lower in the experimental group at 1-week postsurgery (CRP: 40.80 ± 23.17 vs. 60.80 ± 43.12 mg/L, p = 0.021; ESR: 72.06 ± 17.52 vs. 83.87 ± 21.52 mm/h, p = 0.012) and at 1-month postsurgery (CRP: 15.63 ± 6.56 vs. 21.17 ± 13.16 mg/L, p = 0.032; ESR: 25.25 ± 20.44 vs. 38.40 ± 25.26 mm/h, p = 0.024). There were no significant differences in the VAS (2.79 ± 0.90 vs. 2.70 ± 0.84 score, p = 0.689) and KSS (64.31 ± 17.88 vs. 66.57 ± 12.36) at 1-month postsurgery. Experimental group: zero infections; control group: only one infection. Administering vancomycin and calcium sulfate during TKA in RA patients reduces postoperative inflammation, but does not significantly affect infection risk; further research may be necessary for validation.

Understanding the variability of the proximal femoral canal: A computational modeling study.

Statistical shape modeling (SSM) offers the potential to describe the morphological differences in similar shapes using a compact number of variables. Its application in orthopedics is rapidly growing. In this study, an SSM of the intramedullary canal of the proximal femur was built, with the aim to better understanding the complexity of its shape which may, in turn, enhance the preoperative planning of total hip arthroplasty (THA). This includes the prediction of the prosthetic femoral version (PFV) which is known to be highly variable amongst patients who have undergone THA. The model was built on three dimensional (3D) models of 64 femoral canals which were generated from pelvic computed tomography images including the proximal femur in the field of view. Principal component analysis (PCA) was performed on the mean shape derived from the model and each segmented canal. Five prominent modes of variations representing approximately 84% of the total 3D variations in the population of shapes were found to capture variability in size, proximal torsion, intramedullary femoral anteversion, varus/valgus orientation, and distal femoral shaft twist/torsion, respectively. It was established that the intramedullary femoral canal is highly variable in its size, shape, and orientation between different subjects. PCA-driven SSM is beneficial for identifying patterns and extracting valuable features of the femoral canal.

Advantages of customization of osseointegrated implants in transfemoral amputees: a comparative analysis of surgical planning

BackgroundCommercially available osseointegrated devices for transfemoral amputees are limited in size and thus fail to meet the significant anatomical variability in the femoral medullary canal. This study aimed to develop a customized osseointegrated stem to better accommodate a variety of femoral anatomies in transfemoral amputees than off-the-shelf stems. Customization is expected to enhance cortical bone preservation and increase the stem-bone contact area, which are critical for the long-term stability and success of implants.MethodsA customized stem (OsteoCustom) was designed based on the statistical shape variability of the medullary canal. The implantability of the OsteoCustom stem was tested via 70 computed tomography (CT) images of human femurs and compared to that of a commercial device (OFI-C) for two different resection levels. The evaluations included the volume of cortical bone removed and the percentage of stem-bone contact area for both resection levels. Statistical significance was analyzed using paired and unpaired t tests.ResultsThe OsteoCustom stem could be virtually implanted in all 70 femurs, while the OFI-C was unsuitable in 19 cases due to insufficient cortical thickness after implantation, further emphasizing its adaptability to varying anatomical conditions. The OsteoCustom stem preserved a greater volume of cortical bone than did the OFI-C. In fact, 42% less bone was removed at the proximal resection level (3.15 cm³ vs. 5.42 cm³, p ≤ 0.0001), and 33% less at the distal resection level (2.25 cm³ vs. 3.39 cm³, p = 0.003). The stem-bone contact area was also greater for the OsteoCustom stem, particularly at the distal resection level, showing a 20% increase in contact area (52.3% vs. 32.2%, p = 0.002) compared to that of the OFI-C.ConclusionsThe OsteoCustom stem performed better than the commercial stem by preserving more cortical bone and achieving a greater stem–bone contact area, especially at distal resection levels where the shape of the medullary canal exhibits more inter-subject variability. Optimal fit in the distal region is of paramount importance for ensuring the stability of osseointegrated implants. This study highlights the potential benefits of customized osseointegrated stems in accommodating a broader range of femoral anatomies, with enhanced fit in the medullary canal.

EFFECTIVE TREATMENT OF SINGLE-STAGE REVISION USING NON-CONTACT LOW FREQUENCY ULTRASONIC DEBRIDEMENT IN TREATING PERIPROSTHETIC JOINT INFECTIONS: A PROSPECTIVE CLINICAL STUDY

Traditional mechanical debridement can only remove visibly infected tissue and is unable to completely clear all the biofilm that hides within muscle crevices and nerves. This study aims to determine the results of single-stage revision using noncontact low frequency ultrasonic debridement in treating chronic periprosthetic joint infections (PJI).A prospective study of consecutive patients requiring single-stage revision for chronic PJI was performed since August 2021. After mechanical debridement, an 8‑mm handheld non‑contact low‑frequency ultrasound probe was used for ultrasonic debridement at a frequency of (25±5) kHz and power of 90% for 5 minutes. Each ultrasound lasted 10 seconds with 3‑seconds intervals. The probe was repeatedly sonicated among all soft tissue and bsingle interface. The distal femoral canal and the posterior capsule of the knee were fully sonicated with a special right‑angle probe. Chemical debridement was then performed to irrigation the whole operative area. Recurrence of infection, culture results and number of colonies 24 hours after ultrasonic debridement were recorded.A total of 45 patients (25 hips and 20 knees) were included and 43 of them (95.6%) were free of infection at a mean follow-up time of 29 months (24 to 33). There were no intraoperative complications related to ultrasonic debridement (neurovascular and muscle injury, poor wound healing and fat liquefaction). The culture‑positive rate of wound liquid before ultrasonic debridement was 40.0% (18/45), which significantly increased to 75.6% (34/45) after ultrasonic debridement (P=0.001). The median number of colonies 24 hours after ultrasonic debridement was 2372 CFU/ml (310 to 4340 CFU/ml), which was significantly higher than that before debridement (307 CFU/ml; 10 to 980 CFU/ml) (P=0.000).Single-stage revision with non‑contact low‑frequency ultrasonic debridement can fully expose bacteria within biofilm, increase the efficacy of chemical debridement and lead to a favorable short‑term outcome without related complications.

Canal to calcar ratio is associated with lumbar compression fractures

Objective: Osteoporosis is one of the major public health problems. Singh (SI) and Genant indexes are the most well-known osteoporosis evaluation methods. Femoral cortical thickness index (CTI) and femoral canal to calcar ratio (CCR) values have been found to be more informative in the literature. This study aimed to investigate the relationship between SI, CTI, CCR, bone mineral density, and blood tests. Patients and Methods: Hospital digital archives were searched and postmenauposal female patients who underwent bone scanning between 2018 and 2020 were included. Demographic data, blood laboratory and bone mineral densitometry (BMD) test results, and radiographic views were collected. The results were statistically analysed and expressed as mean ± standard deviation. Results: The mean age was 66.14±6.82 years. There were 22 patients with lumbar compression according to Genant criteria. Also, 52 patients had osteoporosis and 35 patients had osteopenia according to the spine or hip BMD T scores. CCR was found to be significantly related to lumbar compression (p=0.04). Conclusion: In this study, no correlation was found between CCR value and T score. However, CCR value was found to be associated with lumbar vertebral compression, which is helpful in the diagnosis of osteoporosis. It may be considered as a parameter that should be studied more in the diagnosis of osteoporosis.

CHARACTERISTICS OF THE RESULTS OF ELECTRICAL EXPOSURE WHEN INDUCING OSTEOMYELITIS IN RATS BY DIFFERENT TYPES OF PATIENTS

The aim of the research. To study the features of the course of osteomyelitis in rats during the induction of an infectious and inflammatory process by various pathogens under conditions of early and delayed local exposure to direct electric current. Materials and methods. The study was carried out on 53 Wistar rats, divided into 3 series. In each series, osteomyelitis of the femur was modeled by direct inoculation into the femoral canal of a monobacterial culture (Staphylococcus aureus; MSSA, museum strain, or Pseudomonas aeruginosa, museum strain, or Escherichia coli, museum strain) at a concentration of 1 × 108 CFU and placing an intramedullary metal implant. The animals of each series were divided into 3 groups. In group 1, no additional manipulations were performed with the animals; in groups 2 and 3, the source of infection was exposed to a direct electric current (150 mAm, 1 minute) on days 0, 2, 4 and 6, or on days 7, 9, 11 and 13. The duration of the experiment was 21 days. Results. All animals had a clinical picture characteristic of osteomyelitis, but the nature, severity and frequency of occurrence of signs of the infectious-inflammatory process in the groups were different. Conclusion. Exposure to electric current early after infection had the most pronounced antimicrobial effect against P. aeruginosa when exposure began on day 7 after infection. A less pronounced effect of electrical exposure was noted in relation to S.aureus and E.coli when exposure began on the first day after infection.

Combination treatment with whole body vibration and simvastatin improves the early osseointegration in aged rats

BackgroundCurrent research has demonstrated that Simvastatin (SIM) and Whole Body Vibration (WBV) actively contributes to the repair of osteoporotic bones. However, there is still limited knowledge regarding the impact of this combined therapy on osseointegration in elderly individuals. Objective: The objective of this study was to verify the influence of WBV and SIM combination treatment on Titanium implants' fixation strength in aged rats. MethodsMale Sprague-Dawley rats at 24 months old were utilized for this investigation. Titanium rods were surgically inserted into the distal femoral canal on their left side. Subsequently, all animals were randomly assigned to one of four groups: Control group; WBV group; SIM group; and WBV + SIM group. Each group received Saline, Whole Body Vibration, Simvastatin, or a combination of Whole Body Vibration plus Simvastatin treatment until they reached their natural death after 12 weeks. The bilateral femurs and serum samples from these rats were collected for evaluation purposes. ResultsBoth WBV and SIM treatments exhibited an increase in bone mass, osseointegration, and push-out force compared to the Control group (all, P < 0.05). Additionally, levels of oxidative stress and inflammatory factors decreased with both treatments when compared to the Control group alone (all, P < 0.05). Notably, the WBV + SIM group displayed superior effects on new bone formation, biomechanical strength, BMP2 expression in bone tissue as well as SOD2 expression regulation related to bone repair genes when compared to other groups involved in this study (all, P < 0.05). ConclusionThese findings suggest that combining physiotherapy (WBV) with drug therapy (SIM) proves beneficial for enhancing implant fixation in aged rats.

Assessing the impact of distal femoral morphology using Citak's ratio: an independent risk factor for aseptic loosening in rotating hinge knee prosthesis.

Aseptic loosening (AL) is a frequent complication after rotating hinge knee (RHK) prosthesis. Citak's ratio has recently been developed to describe and classify distal femoral morphology into 3 groups (A, B, C). It consists in a ratio between the diameters of the femoral canal at 20cm from the knee joint line and at 2cm from the adductor tubercle. The objective of the study was to identify whether the femoral distal anatomical shape described with this ratio represents a risk factor for AL in RHK prosthesis. Retrospective study of patients who had undergone primary or revision RHK prosthesis, with a follow-up of minimum 4 years. Citak's ratio was calculated, and patients were classified depending on its value. Univariate and bivariate statistical analysis was performed to identify AL risk factors. Receiver Operating Characteristics (ROC) analyses were conducted to examine diagnostic quality of the parameters of interest. Thirty-three patients were included. Most of them females (ratio 26:7), with a mean age of 78.2 (SD 6.9). Three patients presented AL (rate of 9%), all of them classified into group C (100%). Citak's ratio was significantly related to the AL rate (p < 0.001), and so was the femoral canal diameter at 20cm from the knee joint (p 0.010). The ROC curve analysis yielded an Area Under the Curve (AUC) of 0.922 (CI 95% 0.819-1.000) for the Citak´s ratio. The inner femoral diameter at 20cm proximal to the knee joint line and Citak's ratio help indentify patients at risk of AL after RHK prosthesis, and thus a better planning of the surgery.

Radiographic evaluation of robot-assisted versus manual total hip arthroplasty: a multicenter randomized controlled trial

BackgroundThe effectiveness of robot-assisted surgery remains contentious due to the lack of high-quality randomized controlled trials (RCTs) to elevate the level of evidence. We aimed to evaluate the postoperative radiographic outcomes of robot-assisted (RAS-THA) versus manual (M-THA) total hip arthroplasty.MethodsThis multicenter RCT was performed from March 1, 2021 to December 1, 2021. Patients were randomly assigned to routine M-THA or to RAS-THA that used the TRex-RS orthopedic joint surgical navigation system. The primary outcome was to compare the acetabular component orientation, femoral stem alignment, femoral canal fill ratio, and leg length discrepancy between RAS-THA and M-THA using postoperative radiography. Subgroup analyses of the two groups stratified by surgical approach, gender, and BMI were also conducted.ResultsSeventy-three participants were randomly allocated to the RAS-THA group, while seventy-two participants were assigned to the M-THA group. Compared to the M-THA group, the RAS-THA group exhibited less variability in the preoperative planning of the vertical center of rotation (VCOR; P < 0.001), demonstrated a significant advantage in femoral stem alignment (P = 0.004), and showed pronounced decreases in inequality and in the variability in leg length discrepancy (P < 0.001). There was no significant difference in the Lewinnek safe-zone ratio (P = 0.081) and the femoral canal fill ratio (P > 0.05) between the two groups. Further subgroup analysis also showed that the RAS-THA group had fewer horizontal center of rotation (HCOR) and leg length differences when stratified by surgical approach, gender, and overweight status.ConclusionThis RCT found that, regardless of the surgical approach, gender, or body mass index, RAS-THA can effectively improve the postoperative VCOR and significantly reduce the variability of leg length difference. RAS-THA should be considered an effective method to enhance surgical precision by achieving less variability in challenging patients with leg length discrepancies.Trial registration: ChiCTR2100044124.

Impact of Prophylactic Cerclage Location on Femoral Fracture Propagation: A Biomechanical Study.

Prophylactic cerclage cables are often placed intraoperatively about a fracture to prevent propagation. However, biomechanical data supporting optimal cable placement location are lacking. The objective of this study was to evaluate the impact of prophylactic cerclage placement location on the propagation of femoral shaft fractures. The diaphysis of 14 fresh-frozen cadaveric femora were included. Volumetric bone mineral density in the femoral shaft was obtained from quantitative computed tomography scans. For each specimen, a 5-mm longitudinal fracture was created proximally to simulate a pre-existing fracture. After reaming of the femoral canal, a 3 degrees tapered wedge was advanced with an MTS machine at 0.2 mm/s until failure. The tests were conducted with a CoCr cable placed at varying distances (5 mm, 10 mm, 15 mm, 20 mm, and cableless) from the distal tip of the initial fracture. A compression loadcell was used to measure the cable tension during the tests. The axial force, displacement, and cable tension were monitored for comparison between groups. In the cableless group, the mean force needed to propagate the fracture was 1017.8 ± 450.3 N. With the addition of a cable at 5 mm below the fracture, the failure force nearly doubled to 1970.4 ± 801.1 N (P < 0.001). This also led to significant increases in stiffness (P = 0.006) and total work (P = 0.001) when compared with the control group. By contrast, in the 15 and 20 mm groups, there were no significant changes in the failure force, stiffness, and total work as compared with the control group (P > 0.05). Propagation of femoral shaft fracture was effectively resisted when a prophylactic cable was placed within 5 mm from the initial fracture, whereas cables placed more than 10 mm below the initial fracture were not effective in preventing fracture propagation.

Lichtenstein technique for inguinal hernia repair: ten recommendations to optimize surgical outcomes

PurposeApproximately 20 million individuals worldwide undergo inguinal hernia surgery annually. The Lichtenstein technique is the most commonly used surgical procedure in this setting. The objective of this study was to revisit this technique and present ten recommendations based on the best practices.MethodsPubMed and Scientific Electronic Library Online were used to systematically search for articles about the Lichtenstein technique and its modifications. Literature regarding this technique and surgical strategies to prevent chronic pain were the basis for formulating ten recommendations for best practices during Lichtenstein surgery.ResultsTen recommendations were proposed based on best practices in the Lichtenstein technique: neuroanatomical assessment, chronic pain prevention, pragmatic neurectomy, spermatic cord structure management, femoral canal assessment, hernia sac management, mesh characteristics, fixation, recurrence prevention, and surgical convalescence.ConclusionThe ten recommendations are practical ways to achieve a safe and successful procedure. We fell that following these recommendations can improve surgical outcomes using the Lichtenstein technique.

Osteotomy Site Venting Enhances Femoral Bone Consolidation With Magnetic Intramedullary Lengthening Nails.

Magnetic intramedullary lengthening nailing has demonstrated benefits over external fixation devices for femoral bone lengthening. These include avoiding uncomfortable external fixation and associated pin site infections, scarring, and inhibition of muscle or joint function. Despite this, little has changed in the field of biologically enhanced bone regeneration. Venting the femoral intramedullary canal at the osteotomy site before reaming creates egress for bone marrow during reaming. The reamings that are extruded from vent holes may function as a prepositioned bone graft at the distraction gap. The relationship between venting and the consolidation of regenerating bone remains unclear. (1) Do bone marrow reamings extruded through venting holes enhance the quality of bone regeneration and improve healing indices and consolidation times? (2) Is venting associated with a higher proportion of complications than nonventing? We performed a retrospective study of femoral lengthening performed at one hospital from December 2012 to February 2022 using a magnetic intramedullary lengthening nail with or without venting at the osteotomy site before reaming. This was a generally sequential series, in which the study groups were assembled as follows: Venting was performed between July 2012 and August 2016 and again from November 2021 onward. Nonventing was used between October 2016 and October 2021 because the senior author opted to create drill holes after the reaming procedure to avoid commitment to the osteotomy level before completing the reaming procedure. Outcomes were evaluated based on bone healing time, time to achieve full weightbearing, and complications. Sixty-one femoral lengthening procedures were studied (in 33 male and 28 female patients); two patients were excluded because of implant breakage. The mean age was 17 ± 5 years. The mean amount of lengthening was 55 ± 13 mm in the venting group and 48 ± 16 mm in the nonventing group (mean difference 7 ± 21 [95% CI 2 to 12]; p = 0.07). The healing index was defined as the time (in days) required for three cortices to bridge with new bone formation divided by the length (in cm) lengthened during the clinical protocol. This index signifies the bone formation rate achieved under the specific conditions of the protocol. Full weightbearing was allowed upon bridging the regenerated gap on three sides. Consolidation time was defined as the total number of days from the completion of the lengthening phase until adequate bone union (all three cortices healed) was achieved and full weightbearing was permitted. This time frame represents the entire healing process after the lengthening is complete divided by the amount of lengthening achieved (in cm). Patient follow-up was conducted meticulously at our institution, and we adhered to a precise schedule, occurring every 2 weeks during the distraction phase and every 4 weeks during the consolidation phase. There were no instances of loss to follow-up. Every patient completed the treatment successfully, reaching the specified milestones of weightbearing and achieving three cortexes of bone bridging. The mean healing index time in the venting group was faster than that in the nonventing group (21 ± 6 days/cm versus 31 ± 22 days/cm, mean difference 10 ± 23 [95% CI 4 to 16]; p = 0.02). The mean consolidation time was faster in the venting group than the nonventing group (10 ± 6 days/cm versus 20 ± 22 days/cm; mean difference 10 ± 23 [95% CI 4 to 15]; p = 0.02). No medical complications such as deep vein thrombosis or fat or pulmonary embolism were seen. Two patients had lengthy delays in regenerate union, both of whom were in the nonventing group (healing indexes were 74 and 62 days/cm; consolidation time was 52 and 40 days/cm). Femoral lengthening with a magnetic intramedullary lengthening nail healed more quickly with prereaming venting than with nonventing, and it allowed earlier full weightbearing without any major associated complications. Future studies should evaluate whether there is a correlation between the number of venting holes and improvement in the healing index and consolidation time. Level III, therapeutic study.

Triggered Release of Ampicillin from Metallic Implant Coatings for Combating Periprosthetic Infections.

Periprosthetic infections caused by Staphylococcus aureus (S. aureus) pose unique challenges in orthopedic surgeries, in part due to the bacterium's capacity to invade surrounding bone tissues besides forming recalcitrant biofilms on implant surfaces. We previously developed prophylactic implant coatings for the on-demand release of vancomycin, triggered by the cleavage of an oligonucleotide (Oligo) linker by micrococcal nuclease (MN) secreted by the Gram-positive bacterium, to eradicate S. aureus surrounding the implant in vitro and in vivo. Building upon this coating platform, here we explore the feasibility of extending the on-demand release to ampicillin, a broad-spectrum aminopenicillin β-lactam antibiotic that is more effective than vancomycin in killing Gram-negative bacteria that may accompany S. aureus infections. The amino group of ampicillin was successfully conjugated to the carboxyl end of an MN-sensitive Oligo covalently integrated in a polymethacrylate hydrogel coating applied to titanium alloy pins. The resultant Oligo-Ampicillin hydrogel coating released the β-lactam in the presence of S. aureus and successfully cleared nearby S. aureus in vitro. When the Oligo-Ampicillin-coated pin was delivered to a rat femoral canal inoculated with 1000 cfu S. aureus, it prevented periprosthetic infection with timely on-demand drug release. The clearance of the bacteria from the pin surface as well as surrounding tissue persisted over 3 months, with no local or systemic toxicity observed with the coating. The negatively charged Oligo fragment attached to ampicillin upon cleavage from the coating did diminish the antibiotic's potency against S. aureus and Escherichia coli (E. coli) to varying degrees, likely due to electrostatic repulsion by the anionic surfaces of the bacteria. Although the on-demand release of the β-lactam led to adequate killing of S. aureus but not E. coli in the presence of a mixture of the bacteria, strong inhibition of the colonization of the remaining E. coli on hydrogel coating was observed. These findings will inspire considerations of alternative broad-spectrum antibiotics, optimized drug conjugation, and Oligo linker engineering for more effective protection against polymicrobial periprosthetic infections.

Comparative analysis of acute blood loss anemia in robotic assisted vs. manual instrumented total knee arthroplasty

IntroductionRobotic assisted total knee arthroplasty has become an increasingly popular technique over the past several years. Manual total knee arthroplasty can be associated with acute blood loss anemia. Instrumentation of the femoral canal with the alignment guide may in part contribute to this blood loss. Because the femoral canal is not entered during robotic assisted total knee arthroplasty, the blood loss may be lower compared to that seen in manual total knee arthroplasty. The purpose of this study was to determine if acute blood loss is greater in manually instrumented total knee arthroplasty versus robotic assisted total knee arthroplasty. Materials and methodsThis retrospective cohort study was performed in a large tertiary academic hospital network by two fellowship trained surgeons. Patients underwent either robotic assisted or manually instrumented total knee arthroplasty and were assessed for postoperative acute blood loss anemia, defined as hemoglobin <13 g/dL for males or <12 g/dL for females plus a 2 g/dL drop from preoperative levels, as well as postoperative drop in hemoglobin. ResultsA total of 75 patients were included in each study arm. There was no significant difference (p > 0.05) in postoperative hemoglobin in robotic assisted (2.1 g/dL) compared to manually instrumented total knee arthroplasty (2.1 g/dL). There was no significant difference in the incidence of postoperative acute blood loss anemia between robotic assisted (45 %) and manually instrumented total knee arthroplasty (39 %). Higher BMI and increased age were protective against postoperative drop in hemoglobin. These protective effects were not significant when controlling for confounding variables. Surgical time was significantly longer for robotic assisted (99 min) versus manually instrumented total knee arthroplasty (86 min) (p < 0.001). ConclusionsThere is no significant difference in acute blood loss when comparing patients undergoing robotic assisted and manually instrumented total knee arthroplasty.

A statistical shape analysis for the assessment of the main geometrical features of the distal femoral medullary canal.

Statistical Shape Models (SSMs) are widely used in orthopedics to extract the main shape features from bone regions (e.g., femur). This study aims to develop an SSM of the femoral medullary canal, investigate its anatomical variability, and assess variations depending on canal length. The canals were isolated from 72 CT femur scans, through a threshold-based segmentation. A region of interest (ROI) was selected; sixteen segments were extracted from the ROI, ranging from 25% of the full length down to the most distal segment. An SSM was developed to identify the main modes of variation for each segment. The number of Principal Components (PCs) needed to explain at least 90% of the shape variance were three/four based on the length of the canal segment. The study examined the relationship between the identified PCs and geometric parameters like length, radius of curvature, ellipticity, mean diameter, and conicity, reporting range and percentage variation of these parameters for each segment. The SSMs provide insights into the anatomical variability of the femoral canal, emphasizing the importance of considering different segments to capture shape variations at various canal length. These findings can contribute for the design of personalized orthopedic implants involving the distal femur.