Nail Lengths Research Articles

Applying machine learning to understand the relationship between body weight and beak and nail dimensions in broiler chickens

The aim of this research was to determine whether body weight could be used as a reliable indicator of beak and claw length in broiler chickens during the production cycle. Sixty broiler chickens were evaluated individually and evaluated weekly (1, 7, 14, 21, 28, 35 and 42 days) throughout the production cycle. The following variables were measured: body weight, length of nails and beaks (maxillary mandible and beak area considering the presence of the nostril). The evaluation of body weight was performed using a digital scale. Nail lengths (U1, U2 and U3) were obtained using a digital calliper. The biomechanical analysis of the length of the beaks of the birds was carried out through photographs, using a digital camera and the analysis of the images carried out through the ImageJ software. It is concluded that the correlations between body weight x maxila, body weight x area of the beak with nostril and body weight x nails (U1, U2 and U3), can be a reliable indicator of dependence between the variables if we consider the complete breeding cycle of broiler chickens. However, when the correlations are evaluated weekly separately, they are not a reliable indicator. The first two main components revealed 94.7% of the data variation, with all morphological variables being important, as the communalities were greater than 0.93. The factorial analysis biplot revealed that nail characteristics, especially Nail1 and Nail 3, are strongly associated with the body weight of birds considering the complete cycle (42 days), i.e. nail characteristics are the main phenotypic predictors of body weight. The morphological traits of the nail and beak are predictors of body weight when evaluating the complete cycle (42 days), especially nail 1 and nail 3.

Extending the intermedullary nail will not reduce the potential risk of femoral head varus in PFNA patients biomechanically: a clinical review and corresponding numerical simulation

Femoral head varus is an important complication in intertrochanteric fracture patients treated with proximal femoral nail anti-rotation (PFNA) fixation. Theoretically, extending the length of the intramedullary nail could optimize fixation stability by lengthening the force arm. However, whether extending the nail length can optimize patient prognosis is unclear. In this study, a review of imaging data from intertrochanteric fracture patients with PFNA fixation was performed, and the length of the intramedullary nail in the femoral trunk and the distance between the lesser trochanter and the distal locking screw were measured. The femoral neck varus status was judged at the 6-month follow-up. The correlation coefficients between nail length and femoral neck varus angle were computed, and linear regression analysis was used to determine whether a change in nail length was an independent risk factor for femoral neck varus. Moreover, the biomechanical effects of different nail lengths on PFNA fixation stability and local stress distribution have also been verified by numerical mechanical simulations. Clinical review revealed that changes in nail length were not significantly correlated with femoral head varus and were also not an independent risk factor for this complication. In addition, only slight biomechanical changes can be observed in the numerical simulation results. Therefore, commonly used intramedullary nails should be able to meet the needs of PFNA-fixed patients, and additional procedures for longer nail insertion may be unnecessary.

Complications and survival rates of subtrochanteric fractures are similar between short and long intramedullary nail fixation and independent of weight-bearing

PurposeIntertrochanteric fractures are treated surgically, allowing rapid weight-bearing to improve ambulation and lower complications and mortality. Subtrochanteric fractures are mechanically less stable and are traditionally treated with a non-weight approach and longer intramedullary nails. This study compared immediate weight-bearing versus limited weight-bearing and different intramedullary nail lengths regarding patient outcomes.MethodsWe analyzed all consecutive cases of low-energy subtrochanteric fractures treated surgically at our institution between January 2016 and November 2020. One hundred and nine patients were found. We compared nail length and immediate versus delayed weight-bearing concerning the length of stay, time to painless ambulation, time to radiographic fracture union, and revision rates. Fracture severity was also examined using the Seinsheimer classification.ResultsLength of stay and time to painless ambulation were shorter in the immediate weight-bearing group. Time to radiographic union and rate of complications were lower; however, they were not statistically significant. Conversely, no significant difference in revision rates was found. Regarding nail length, the length of stay was shorter, and the time to painless ambulation was faster in the short-length group. The rate of complications and time to union were similar. No difference in revision rate was found. Seinsheimer classification of the fracture did not influence the decision to allow weight-bearing or nail selection (p = 0.65).ConclusionsThis study demonstrates that immediate weight-bearing as tolerated and short intramedullary nails allow a quicker time for painless ambulation and hospitalization, with possibly fewer perioperative complications and faster radiographic union, without increasing complications.

Evaluation of the mechanical behaviour of the expandable wedge locked nail fixation in retrograde use: A finite element study

IntroductionIn literature, there have been many studies conducted to research the alternatives of standard interlocking intramedullary nailing. The expandable wedge locked nail fixation, which is thought as a new alternative to the standard interlocking nailing, has been presented in previous numerical studies. The antegrade usage of the wedge locked nail fixation has provided promising results. From this point, the aim of the study is to evaluate mechanical behavior of its retrograde usage on femur models. Additionally, another aim of the study is to investigate the effect of fracture level on mechanical properties of the fixation. Materials and methodsThe mechanical behaviors of the wedge locked nail and standard interlocking nail fixations were compared by finite element methods. Sawbones femurs having osteotomies at five different levels to simulate different fractures were fixed with wedge locked nail or interlocking nail by using retrograde approach. With respect to the fracture level, two different nail lengths were used. Axial compression load was applied to fixations. The mechanical behaviors of the fixations were evaluated with respect to stiffness of the fixations and stresses occurred on both implants and bones. ResultsAny of the wedge locked nail fixation did not slip at canal. The stress and stiffness results were mostly close with each other for both nail types. The maximum stresses at locking elements or bones contacting these elements increased with decreased distance between the fracture and relevant locking elements. DiscussionThe wedge locked nail fixation showed comparable results to the standard interlocking nail fixation with respect to the stiffness and stress. Under axial loading, wedge locked nail provided a secured fixation without any slippage and preserved its position inside the medullary canal. It may be thought as a safe alternative to the standard interlocking nail fixation for retrograde usage. Additionally, according to stress results, it is advised to the surgeons to avoid a close locking to the fracture line.

Numerical investigation on performance of nail stabilised vertical cuts

Soil nailing is an earth retention technique commonly used for stabilising steep slopes, retaining excavations and helps in maintaining the ground surface at two different elevations. Ease of installation, economic efficiency and effective performance of soil nailed structures under different loading conditions has resulted in the rapid use of the technique in different temporary and permanent construction applications. This study deals with the finite element analysis of 6 m and 10 m high vertical soil nailed walls to evaluate the performance under static loading. The characteristics of structures are evaluated under different nail inclinations, nail lengths and different site conditions. The response of soil nailed structures under different parameters are assessed with respect to maximum horizontal displacement of the wall, maximum axial force developed along the nail length and lateral earth pressure distribution on the nailed wall. An optimum nail inclination of 15° and nail length ratio of 0.7 has been identified as best suited for a stable vertical cut.

Preoperative estimation of humerus intramedullary nail length using clinical landmarks

PurposeIntramedullary interlocking nailing is one of the accepted methods of treating humerus diaphyseal fractures. Appropriate nail length and diameter are of paramount importance to achieve a stable fracture fixation. Estimating the nail length can be as challenging in certain cases as it is important. This study aims to provide an easy-to-use formula utilizing clinical measurements from contra lateral arm to accurately estimate humeral nail length. MethodsThis descriptive cross-sectional study was conducted at 3 tertiary care hospitals in Mangalore, India. Patients above the age of 18 years coming to the outpatient department with elbow, shoulder or arm complaints requiring radiological investigation from July 2021 to July 2022 were included. Patients with fractures or dislocations of upper limbs, malunited or non-united fractures of upper limbs, congenital or developmental deformities and patients with open growth plates were excluded. Patients’ variables (like age and gender), radiological humerus length and contralateral arm clinical measurements were recorded. An independent samples t-test was used for univariate analysis, and linear regression analysis was done to estimate the desired nail length using the clinical measurement of the humerus (cm) in both genders separately. The significance level was set at p < 0.05. ResultsOur study included 204 participants of which 108 were male and 96 were female. The formula for predicting humeral nail length in males is (−2.029) + (0.883 × clinical measurement). The formula for females is 1.862 + (0.741 × clinical measurement). A simplified formula to determine humeral nail length is 0.9 clinical length – 2 cm (in males) and 0.7 × clinical length + 2 cm (in females). ConclusionTo improve the stability of fixation with intramedullary nails it is imperative to select the appropriate nail length. There have been studies that devised reliable methods of determining nail lengths in the tibia and femur using preoperative clinical measurements. A similar clinical method of determining humeral nail length is lacking in the literature. Our study was able to correlate radiological lengths of the humerus medullary canal with clinical measurements performed using anatomical landmarks to arrive at a formula. This allows for a reliable and easy nail length determination preoperatively.

Seismic stability analysis of heterogeneous slopes reinforced by inclined soil nails

This study aims to propose an effective approach to evaluate the seismic stability of heterogeneous slopes reinforced by inclined soil nails. The modified pseudo dynamic approach is applied to properly describe the characteristics of seismic loads with time and space. The discretization-based failure mechanism generated from the slope crest is divided horizontally into many blocks to incorporate the heterogeneous soil properties and depth-dependent seismic accelerations into the analysis of the stability issue. The critical seismic acceleration coefficient is then determined to assess the slope stability using the kinematic approach of limit analysis. The proposed method is validated by comparisons with existing solutions and numerical results for some available cases. A systematic parametric analysis is conducted to discuss the effects of model parameters on the slope stability. Results show that there exist optimal relative nail lengths and optimal incline angles of soil nails to obtain the maximum critical seismic acceleration coefficient for reinforced slopes. Finally, an application of the proposed model to spatially variable soil strength properties is performed to illustrate that the proposed method has the potential to serve as a benchmark for the slope stability under complex geological conditions.

Reduced cutout for reverse oblique intertrochanteric hip fractures treated with trochanteric fixation advanced (TFN-A) nail compared to the short gamma-3 nail.

Reverse oblique fractures (AO/OTA 31-A3) account for 5-23% of all intertrochanteric fractures and are challenging to manage. The Gamma 3-Proximal Femoral Nail (GPFN) and the Trochanteric Fixation Nail Advanced (TFNA) are two common cephalomedullary systems used to treat this fracture. No study has reported on outcomes with the TFN-A for reverse oblique fractures. This study aimed to compare outcomes and complication rates in patients with reverse oblique fractures, treated with either TFNA or GPFN. A total of 203 patients with reverse oblique fractures (137 in the GPFN group and 66 in the TFNA group), were treated in our institution between June 2010 and May 2019. Data was collected on postoperative radiological variables including screw or blade location, and tip-apex distance (TAD). Data were also collected for non-orthopaedic complication rates and orthopaedic complications. A sub-group analysis was additionally performed for different nail lengths. We found no significant difference in the overall rate of complications and revisions between the two groups. Patients treated with the 235mm TFN-A nail sustained lower rates of cutout, compared to 180mm GPFN (GPFN: 6% TFN-A: 0%, p=0.043). The frequency of revision surgeries and malunions/non-unions did not differ significantly between the two groups and additionally showed no difference in the subgroup analysis. The 235mm TFN-A was associated with lower rates of cut-out compared to the short GPFN for reverse oblique intertrochanteric fractures. Future well-designed prospective studies are warranted to investigate the role of the TFN-A in improving outcomes for such fractures.

An Innovative Post Grouting Technique for Soil Nails

This study presents an innovative technique of executing soil nails called sectorized post grouting (SPG). The most utilized technique of soil nail grouting is gravity grouting, with the literature reporting advances in pressurized grouting. Although obtaining higher pullout resistance of soil nails, pressurized grouting, mostly done in single-stage grouting, does not compensate for exudation and its use in higher nail lengths is difficult. Thus, a technique has been developed that compensates for exudation, with easier application in lengthier nails. The technique was qualitatively assessed to evaluate its surface roughness and later applied in seven real soil nailing works, where it could be quantitatively assessed. The results show that sectorized post-grouted nails obtained greater pullout resistances than gravity grouted and single-stage grouted nails. Although similar improvement was found in tube-à-manchette (TAM) grouted nails, this method presents lower economic efficiency than sectorized post grouting. The pullout resistance results obtained in this study can be utilized in future soil nailing works executed utilizing SPG.

The impact of gel fingernail polish application on the reduction of bacterial viability following a surgical hand scrub.

To determine the effect of gel nail polish application on the reduction of bacterial viability immediately after a surgical hand scrub. Randomized controlled trial. Ten fingernails each from 40 female health care professionals and students. Participants' fingernails were randomized to receive no polish or gel nail polish during a manicure from a licensed manicurist. One day and 14 days after manicure, participants' fingernails were sampled before and after a surgical hand scrub with chlorhexidine gluconate. The samples for each fingernail were serially diluted, plated on a Trypsin sheep blood agar and MacConkey's agar plate, and incubated for 36 h. For each plate, bacterial colony forming units (CFU)/ml were determined. Mixed linear models were used to assess factors associated with the logarithmic reduction of viable bacterial counts from pre- to post-surgical scrub. In the final model, no association was detected between gel nail polish and reduction of viable bacterial count (p=.09). On Day 14, among longer nail lengths (2 to <3-mm and ≥3-mm), surgical scrubs resulted in greater reduction in bacterial counts in left-handed than right-handed participants (p < .01). Increasing nail length was correlated with increased CFU/ml post-scrubbing (p < .001). Application of gel nail polish did not seem to affect the ability of surgical scrub to reduce bacterial viability 1 and 14 days after a manicure. This study does not provide evidence to prevent application of gel nail polish on short fingernails in surgeons prior to surgical hand scrub with chlorhexidine gluconate.

Shaking Table Tests to Evaluate the Seismic Performance of Soil Nailing Stabilized Embankments

A series of shaking table tests will be carried out on 0.4 m high instrumented soil nailed embankments. The important parameters considered in this study consist of a combination of three different slope angles (β = 30°, 45°, and 60°), three different nail inclinations (i = 0°, 15°, and 30°), and three nail lengths (l = 0.2, 0.3, and 0.4 m). This study revealed that the effect of slope angle on the seismic resistance of steep nailed soil slopes was significant and the minimal magnitude of the facing displacement was obtained with nail inclinations of 0° and 15° for the nailed slopes without facing and with facing, respectively. A model nailed slope with a nail inclination of 15° provided better reinforcement action than the horizontally and 30° inclined nails when stabilizing soil slopes. The maximum axial nail force was obtained at approximately two-thirds of the nail length in the model slopes with facing and at the slope facing for model slopes without facing.

Biomechanical behavior of retrograde intramedullary nails in distal femoral fractures

Fractures of the distal femur affect three different groups of individuals: younger people suffering high-energy trauma, elderly people with fragile bones and people with periprosthetic fractures around previous total knee arthroplasty. Main indications of intramedullary nailing are for supracondylar fractures type A or type C of the AO classification.The main objective of the present work is to analyze, by means of FE simulation, the influence of retrograde nail length, considering different blocking configurations and fracture gaps, on the biomechanical behavior of supracondylar fractures of A type.A three dimensional (3D) finite element model of the femur from 55-year-old male donor was developed, and then a stability analysis was performed for the fixation provided by the retrograde nail at a distal fracture with different fracture gaps: 0.5 mm, 3 mm y 20 mm, respectively. Besides, for each gap, three nail lengths were studied with a general extent (320 mm, 280 mm and 240 mm), considering two transversal screws (M/L) at the distal part and different screw combinations above the fracture. The study was focused on the immediately post-operative stage, without any biological healing process.In view of the obtained results, it has been demonstrated new possibilities of blocking configuration in addition to the usual ones, which allows establishing recommendations for nail design and clinical practice, avoiding excessive stress concentrations both in screws, with the problem of rupture and loss of blocking, and in the contact of nail tip with cortical bone, with the problem of a new stress fracture.

Experimental and numerical study on lateral and longitudinal resistance of ballasted track with nailed sleeper

ABSTRACT Lateral and longitudinal resistance of ballasted track are two main indicators for the track stability quantification. Aiming at improving the lateral and longitudinal resistance, nailed sleeper is studied with single sleeper push tests (SSPTs) and discrete element modelling (DEM). The SSPTs were applied to study how much resistance the nailed sleeper can improve, considering different nail lengths (100, 200, 400 mm), and also used to calibrate and validate the DEM models. With the validated DEM models, different simulation conditions were performed and compared to confirm the optimal nail length (100, 200 mm) and nail number (2, 4). Results show that applying nailed sleepers improves the lateral resistance by 53.7% and the longitudinal resistance by 39.2%. 4 nails, compared to 2 nails, can increase lateral and longitudinal resistance by 20.2% and 10.6% (nail length: 100 mm) as well as 37.0% and 33.5% (nail length: 200 mm), respectively.

INSTRUCTORS’ VIEWS ON CONCURRENT APPLICATIONS OF PIANO AND GUITAR LESSONS

This study, which aims to make an evaluation in the light of the opinions of the instructors regarding the simultaneous application of piano and guitar trainings in vocational music education, is considered appropriate to the screening model, besides carries a qualitative dimension. The data used in the study were obtained by means of the questionnaire applied to 14 piano and 9 guitar lesson faculty members instructors who work in various vocational music training units in universities in Turkey during the 2018-2019 academic year prepared according to the standardized open-ended interview approach. According to the relevant faculty members, regardless of the context in which piano education is handled, a certain basic understanding of the technique will be adopted, and the guitar students will have difficulties in realizing the balances and subsequent target behaviors of the piano technique due to their relatively long nail lengths. In light of the opinions of the lecturers of both courses, it was concluded that awareness should be provided on the subject and student-oriented fair approaches should be developed in coordination with the aim of maximum benefit in education.

Shaking table modeling of MSE/soil nail hybrid retaining walls

A series of 1-g shaking table tests using variable-amplitude harmonic excitations was performed on 0.8-m-high MSE/soil nail hybrid retaining (MSE/SN) wall models to investigate the seismic behavior of this innovative retaining earth structure. The tests were conducted on physical wall models with strips having a constant length and different nail lengths under loading conditions with different peak accelerations and durations. It was found that the deformation mode and the horizontal displacements of the MSE/SN walls were highly dependent on the length of the nails, such that L/H = 0.7 can be defined as the critical ratio in seismic conditions for MSE/SN walls which have been reinforced with strips having a constant length. Irrespective of the different nail lengths, the pattern of the observed failure mechanism included a moving block which was delineated by a two-part failure plane consisting of a concave curve and an inclined line with a certain point of intersection. Also, a consistent range of the normalized horizontal displacements (Δx/H), about 0.55–1.10%, corresponding to the formation of local shear bands, and a range of Δx/H = 5.0–5.6%, corresponding to the development of active wedge failure, were determined.

Study on Tensile Properties of Composite Structure Shear Connector

In this paper, the ABAQUS dynamic display analysis method is used to realize the quasi-static analysis of the welding nail. The correctness of the finite element model is verified by comparing with the existing experiments. The finite element simulation calculated four different nail lengths hs, and the calculated simulation values were in good agreement with the experimental values. In the case of the failure mode, when the welding nail is too short and the length-to-diameter ratio of the welding nail is less than 5.92, the whole of the welding nail together with the broken concrete in the surrounding area is pulled out, and when the aspect ratio satisfies certain requirements, the welding nail is generated. Necking, the concrete slab is not broken, and the ultimate tensile bearing capacity is relatively close.

Seismic performance of soil-nailed walls using a 1g shaking table

To assess the seismic performance of soil-nailed walls, a series of 1g shaking table tests was conducted on 0.8 m high wall models with different nail lengths. It was found that the seismic deformation mode of walls highly depends on the nail length and input motion parameters. The combination of a base sliding and rotating deformation mode was observed as the predominant mode of deformation and the length to height (L/H) ratio of 0.7 was presented as the critical ratio in seismic conditions. The pattern of the observed failure mechanisms was similar to a third-degree polynomial failure surface with a specific inflection point. Irrespective of different nail lengths, the threshold acceleration corresponding to the onset of plastic displacements was similar and equal to 0.5g for all models. Based on the formation of initial cracks, a range of Δx/H = 0.33%–0.56% (where Δx is the lateral displacement of the facing) was found as a transitional level from quasi-elastic to plastic state. Also, based on the initial development of the active wedge failure, a range of Δx/H = 3.3%–4.3% was found as a transitional level from plastic to failure state.

The effect of nail characteristics on surface bacterial counts of surgical personnel before and after scrubbing.

To determine the influence of nail characteristics on bacterial counts on the fingers of surgery personnel. Randomized nonblinded controlled crossover study design. Veterinary students, small animal surgery technicians, small animal surgery interns/residents, and small animal surgery faculty in a veterinary teaching hospital (n = 21). Subjects were randomized into one of 2 groups; group 1 wore nail polish (P) for 1 week and group 2 (control) had nonpolished (NP) fingernails. Each subject changed groups the following week. Fingernail lengths were measured each day and fingernail samples were collected before and after presurgical scrub and after surgery. Total bacterial counts (TBC) and suspected staphylococci were counted on blood agar media and mannitol salt agar. The association between bacterial counts and nail biting, position of the volunteer, duration of the surgery, whether the nail polish was chipped, duration of nail polish application, type of surgery, and handedness was tested. Log-transformed CFU counts were compared with a Student's t test and presence or absence of bacteria were compared using Fisher's exact test. TBC, quantities of staphylococci, other gram-positive organisms, and gram-negative bacilli did not differ between P and NP personnel. The only variable associated with higher bacterial counts consisted of nail lengths greater than 2 mm. Nail polish did not influence bacterial counts and types of isolates, but nail length is a risk factor for increased bacterial counts. Based on our results, we recommend that nail length be kept under 2 mm.

The role of the intramedullary implant in limb lengthening

Limb lengthening is now an accepted practice in orthopaedic surgery. The principles of distraction osteogenesis have become well established with the use of external fixators, utilizing both monolateral and ring fixators. Corticotomy technique, frame stability, lengthening rate and rhythm all contribute to the formation of bone regenerate and tissues. Complications are however common including pin-site infection, soft tissue tethering from the pins and wires resulting in pain, regenerate deformity from soft tissue forces or fracture following frame removal and patient intolerance of the frames during treatment.Surgical techniques have changed to try and minimise these complications. The use of intramedullary nails have been used in conjunction with an external fixator or inserted after lengthening has been achieved, to reduce fixator time and prevent regenerate deformity. Implant innovation has led to the production of intramedullary lengthening nails. The initial devices used ratchet mechanisms with rotation of the bone fragments to achieve lengthening (Bliskunov, Albizzia and ISKD). More accurate control of lengthening and a reduction in pain, resulting from the manual rotation of the leg required to achieve the ratchet progression, was achieved by the use of a transcutaneous electrical conduit powered by external high frequency electrical energy (Fitbone).The most recent implant uses an external remote controller which contains two neodymium magnets. These are placed over the nail on the skin and rotate which in turn rotates a third magnet within the intramedullary nail (Precice). This magnet rotation is converted by a motor to extend or retract the extendible rod. There are multiple nail sizes and lengths available, and early results have shown accurate control with few complications. With such promising outcomes the use of this lengthening intramedullary nail is now recommended as the implant of choice in femoral lengthening. This article is an historical account of the intramedullary device and the impact on limb lengthening.

Comparative analysis of type 1 and type 2 cassava peeling machines

A comparative analysis of type 1 and type 2 cassava peeling machines with nail lengths of 26mm and 20mm were investigated in order to improve peeling techniques of cassava tubers. The machines were evaluated at four (4) different speeds; (80rev/min, 90rev/min, 100rev/min, and 110rev/min), with 750HP petrol engine. Cassava tubers were graded into average weights of 0.81kg, 0.72kg, 0.64kg, 0.55kg, 0.50kg. The results of the properties evaluated for type1 and type 2 peelers are: Weight of peeled cassava (85% and 78%) at 80rev/min respectively, Weight of cassava peels (16% and 15.66%) at 80rev/min respectively, Weight of cassava flesh loss (0.7% and 3.26%) at 80rev/min respectively, weight of unpeeled cassava (0.7% and 3.26%) at 80rev/min respectively, Peeling efficiency (88% and 82%) at 80rev/min respectively, Mechanical damage (0.0084kg and 0.040kg) at 80rev/min respectively, Throughput capacity (1041kg/h and 1149kg/h) at 110rev/min respectively, The results of the properties evaluated for type 1 peeler were better than type 2 peeler. http://dx.doi.org/10.4314/njt.v36i2.21