Nail Length Research Articles

Studying the effect of geometrical nail layout on the performance of soil-nailed walls: Physical and numerical modeling

Soil nailing is a reliable method of stabilising earth and rock slopes, but the geometrical layout of soil nails has not been well studied. The current research examined the effect of the geometrical layout of soil nails using analytical and physical modelling. The results of limit equilibrium analysis for different nail layouts are presented. The target gravity level was 50g for centrifuge models and all models had a safety factor of 1.35 at this level. The parameters studied were base nail length, angle of nail tail extension, horizontal spacing of nails, and nail density. The limit equilibrium results showed that, when longer nails were used, the nail density could be decreased. The results of centrifuge modelling confirmed that different layouts at a similar safety factor did not show similar levels of displacement. Also, nail density was the most influential parameter affecting soil-nailed wall performance. An empirical relationship was observed between displacements of the wall crest and nail density. An interesting similarity was observed between the predicted slip surface and the slip surface that formed during physical modelling.

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.

Formulae derived from Anthropometric Measurements to Estimate Ideal Tibial Nail Length.

ABSTRACTIntroduction: Ideal Nail Length (INL) provides better outcomes after Intramedullary Nailing (IMN) of Tibia Shaft Fractures (TSF). Intraoperative methods do not allow for preoperative planning. Changing the nail may cause complications. X-rays are commonly used, but displacement or magnification errors may occur. Forearm measurements may be benefical in bilateral TSF. We aim to examine correlations of anthropometric measurements (AMs) and INL and use them to obtain formulae. Materials and methods: Tuberositas Tibia-Medial Malleolus (TM), Tuberositas Tibia-Ankle joint (TA), knee-ankle joint (JJ), and olecranon tip-5th Metacarpal head (OM) distances were evaluated in 76 IMN patients. Correlation analyses were performed and the results used to create formulae. Results: The correlations between INL and TM-left, TM-right, TA-left, TA-right, OM-left, OM-right, JJ-left, JJ-right were 0.81, 0.83, 0.77, 0.77, 0.82, 0.80, 0.90, 0.91 respectively for males; and 0.93, 0.89, 0.88, 0.86, 0.80, 0.82, 0.90, 0.89 respectively for females. AMs show excellent correlation in both sexes (p<0.0001). Regression analysis was statistically significant in all formulae. The most compatible correlations in males were JJ-right and JJ-left; and in females, TM-left, TM-right, and JJ-right. Conclusion: The most compatible correlations wth INL were JJ in males, and TM and JJ in females. OM can be used in the presence of bilateral TSF, edema, wounds and obesity. AMs are useful preoperatively. The formulae can be used to ensure INL and reduce errors, time and radiation. Level of Evidence: Level I, Testing of previously developed diagnostic criteria on consecutive patients (with the universally applied reference gold standard).

Anatomical and biomechanical parameters relating to migration of the helical blade in proximal femoral fractures fixed by proximal femoral nail anti-rotation

Introduction: Proximal femoral fractures fixation pose dilemma on fixation device to use. Western designed copied proximal femoral nail anti rotation is being used in South-East Asian population extensively. The study aims to study of migration in our population representative of the developing nations. Methods: 92 patients enrolled in prospective cross-sectional study for 9 months; 89 were evaluated for final migration studies as 3 major complications occurred. The effects of age, fracture, tip-apex distance, quadrant position in femoral head, blade size and length and Neck Shaft angle on migration were analyzed. Results: There were 42 males and 50 females with the mean age was 68.14 years. At the time of fixation mean Tip Apex Distance was 12.2 mm (7.0mm – 25mm). At 6 months follow-ups, migration occurred in 78.65%. On univariate analysis, there was no effect of fracture pattern on migration (p=0.524). Femoral-Neck shaft angles were fixed in varus in 7, 5 in valgus and 77 within normal range. Relatively higher migration did occur with varus fixation but was not statistically significant (p=0.306). Multivariate analyses were done for nail diameter, nail length, old age and fracture patterns with no statistically significant interactions. The position of helical blade in the quadrant of the femoral head with center-center having minimum migration (p= 0.000). Major complications occurred in 3 patients. Conclusions: All helical blades do migrate but within acceptable range provided fixation in acceptable Tip Apex Distance. Bone Mineral Density should be kept as co-variable in further studies.

Study on the effect of some parameters of soil nails on the stability of vertical slopes

Soil nailing is one of the soil reinforcement techniques that has been used worldwide in geotechnical engineering. In Viet Nam, soil nailing technology applied in a number of transportation investments such as Ha Long - Van Don, Bac Giang - Lang Son highways, and some of the hydropower plants in the central provinces of Viet Nam. Soil nailing is a system consisting of reinforced concrete piles and rebars or composite rods installed in an inclined direction into the slope. The research and applications of soil nailing technology to reinforceslopes in Viet Nam have not been widespread. The authors only considered construction technologies, processes, requirements for the materials, equipment, quality - check of soil nails, etc. The optimal geometries of soil nails for the stability of slope are inadequate and analyzed thoroughly. These lead to inaccurate prediction of the construction stabilization effect and the safety of designed structures. In the present study, numerical simulations were conducted to investigate the effects of the inclined angle and the length of soil nail Patterns and subjected to surcharge loads on stability improvement of soil - nailed slopes and facing deformation in a staged - excavation. The research results show that the soil nail reinforcement efficiency could be affected by inclinations and length Pattern s of soil nails. The general conclusion is that the more soil is nailing inclinations, the more the reinforcing forces in the soil nails. The soil nail length Patterns have also influenced displacement characteristics of slopes.

Modified Oblique Triangular Neurovascular Island Flap Technique to Prevent the Development of Hooked Nail Deformity.

Hooked fingernail deformity can develop after any type of fingertip amputation. A more proximal amputation is associated with a higher probability of developing hooked fingernails. Proximal fingertip amputations with very short remaining nail beds are recommended for revision amputation with nail bed ablation. This procedure eliminates the possibility that the patient may have a functional nail. When the nail matrix is still retained, an oblique triangular neurovascular island flap may preserve the nail and digit length. At our institution, the modified oblique triangular neurovascular island flap is routinely used for patients who underwent fingertip amputation with a retained nail bed. These modifications may aid in preventing the development of hooked nail deformity and creating a round pulp contour without the need for fixation, composite grafts, or distant soft tissue transfer.

Long PFN nailing in comminuted high subtrochanteric fractures femur in lateral position on ordinary table

Introduction: Most of the hip fractures are managed in supine position on a fracture table with foot attached to foot plates and biplanar fluoroscopy supervision under c-arm. But this procedure has its own difficulties in managing especially comminuted subtrochanteric fractures, where in different fragments and segments are being pulled by strong muscles around hip, and getting good reduction and alignment is difficult due to displaced bony fragments being held in traction on fracture table and cannot be manipulated easily. This leads to prolonged operative time, opening of fracture site, increased bleeding, increased chances of infection and over all increased anaesthesia time adding up to risk factors. The purpose of this study was to report how these difficulties can be overcome by operating on a simple radioluscent top operating table in lateral position without a fracture table. Materials and Methods: 74 cases of subtrochanteric fractures with or without comminution were operated in lateral position on simple ordinary radioluscent top table with lesser attachments and adjustments to operating table during the study duration were included in the study. We used long Proximal Femur Nail (PFN) (length more than 25cms 34, 36, 38, 40cms long) to fix these fractures. Results: In the present study, age group of patients was 25yrs to 74yrs. Male patients (83.7%) were more than female patients (16.3%) An average of less than 150 ml in closed surgery. The average operative time for all cases was 80 minutes. Union time varied from 16 weeks in simple fractures to 26 weeks in comminuted fractures. Clinical function of hip and knee was excellent with full range of movements. Conclusions: Reduction and fixation of proximal femoral fractures in the lateral position with fluoroscopy or portable radiography in the anteroposterior view for small set ups and rural hospitals that lack a fracture table or advanced fluoroscopic devices may be executable and probably safe. Keywords: L

Unstable lateral femoral fractures: elements predictable of failure

Objective. Lateral femoral fractures are common events, especially in old frail patients. They can be stable or unstable on the basis of specific features. Optimal treatment requires preoperative evaluation of the fracture pattern and appropriate choice of implant and surgical technique. The aim of this study was to detect variables related to fixation failure in unstable lateral femoral fracture. Methods. We retrospectively evaluated 136 patients treated with intramedullary proximal femur nail (PFN) between January 2016 and December 2017 at our hospital. All fractures were classified according to the AO/OTA classification; the type and length of nail, nail collodiaphyseal angle, type of distal locking and use of steel wire cerclage were recorded. These variables were statistically analysed to evaluate any correlation with the onset of complications, i.e., biological and/or mechanical failure. Results. At the first follow-up at three months, we found 13 failures (9.6%). At 6 months, 38 patients were lost to follow-up and we identified 3 failures as pseudoartrosis. Statistical analysis showed a significant correlation between the type of fracture and failure. No significant differences were detected for the other parameters. Conclusions. When treating a lateral unstable femoral fracture with proximal femoral nail, the only variable significantly related to failure seems to be the fracture pattern. Thorough knowledge of the implant still remains essential to obtain a good result.

ASSESSMENT OF POPULATION CHARACTERISTICS AND HABITAT USE OF Podocnemis vogli (MÜLLER 1935) DURING A REPRODUCTIVE SEASON AT THE BOJONAWI PRIVATE NATURE RESERVE (VICHADA DEPARTMENT, COLOMBIA)

We conducted a short study in the Bojonawi Private Nature Reserve (Vichada department, Colombia) in three types of aquatic macrohabitats to characterize habitat use, population structure and reproductive phenology of Podocnemis vogli during one reproductive season. We also reevaluated the degree of sexual dimorphism in this species. To maximize capture rates, we used three methods: funnel traps, trammel nets, and manual capture. Only the funnel traps could be used in a standardized manner in all three macrohabitats. We captured 149 individuals in all age/size classes and obtained 11 recaptures. Since we were able to standardize sampling effort with the funnel traps in all macrohabitats, we compared habitat use and class structure among habitats during this reproductive season. There were no significant differences among the three macrohabitats in terms of relative abundances or size class distributions, but sex ratios differed, with an excess of males in the river and females in the lagoon. As with other congeners, P. vogli is a sexually dimorphic species where females attain larger sizes. In this study we documented that pre-cloacal tail length and nail length on the anterior third toe are the most useful secondary sexual characteristics for sexing subadult and adult individuals. Some females larger than 22 cm straight-line carapace length had calcified eggs in their oviducts. This species is abundant within the reserve and appears to be a habitat generalist, including the use of large rivers. More extensive and intensive monitoring is needed to document specific class survivorship rates, detectabilities and population dynamics.

Pseudostatic analysis of soil nailed vertical wall for composite failure

ABSTRACT In the present study, pseudostatic method is used to analyse the stability of soil-nailed vertical wall under seismic conditions. This approach includes an additional inertial force equivalent to the dynamic load caused by earthquake. The soil surface which undergoes failure due to the static and dynamic condition is assumed to be a realistic composite failure surface rather than the conventional planar, circular or log-spiral surfaces. This study investigates the effect of various parameters such as vertical and horizontal seismic acceleration coefficients, friction angle of soil, shear wave velocity, primary wave velocity, amplification factor, nail length, spacing of the nails, and nail inclination on the stability of the vertical soil-nailed wall. A comparison study is made between the results obtained from the present analysis and the values reported in the literature. It is observed the present study with composite failure surface gives higher values of Factor of Safety compared to planar failure surface. Composite failure surface is more realistic and hence more accurate compared to a planar failure surface which gives a conservative value of Factor of Safety.

How are peri-implant fractures below short versus long cephalomedullary nails different?

Cephalomedullary nails are a commonly used implant for the treatment of many pertrochanteric femur fractures and are available in short and long configurations. There is no consensus on ideal nail length. Relative advantages can be ascribed to short and long intramedullary nails, yet both implant styles share the potentially devastating complication of peri-implant fracture. Determining the clinical sequelae after fractures below nails of different lengths would provide valuable information for surgeons choosing between short or long nails. Thus, the purpose of the study was to compare injury patterns and treatment outcomes following peri-implant fractures below short or long cephalomedullary nails. This was a multicenter retrospective cohort study that identified 33 patients referred for treatment of peri-implant fractures below short and long cephalomedullary nails (n = 19 short, n = 14 long). We compared fracture pattern, treatment strategy, complications, and outcomes between these two groups. Short nails were associated with more diaphyseal fractures (odds ratio [OR] 13.75, CI 2.2-57.9, p 0.002), which were treated more commonly with revision intramedullary nailing (OR, infinity; p 0.01), while long nails were associated with distal metaphyseal fractures (OR 13.75, CI 2.2-57.9, p 0.002), which were treated with plate and screw fixation (p 0.002). After peri-implant fracture, there were no differences in blood loss, operative time, weight bearing status, or complication rates based on the length of the initial nail. In patients treated with revision nailing, there was greater estimated blood loss (EBL, median 300cc, interquartile range [IQR] 250-1200 vs median 200cc, IQR 100-300, p 0.03), blood product utilization and complication rates (OR 11.1, CI 1.1-135.7, p 0.03), but a trend toward unrestricted post-operative weight-bearing compared to patients treated with plate and screw constructs. Understanding fracture patterns and patient outcomes after fractures below nails of different lengths will help surgeons make more informed implant choices when treating intertrochanteric hip fractures. Revision to a long nail for the treatment of fractures at the tip of a short nail may be associated with increased patient morbidity.

Principles of Motorized Internal Lengthening of Long Bones

Motorized intramedullary lengthening nails (ILNs) have revolutionized limb lengthening surgery and led to an expansion of indications utilizing them for both upper and lower limb lengthening, fracture compression, and nonunion treatment. There are biological and mechanical differences between using ILNs and using external fixators for lengthening surgery that the treating surgeon must be familiar with. Biological factors include regenerate quality, healing indices, and regenerate complications. Mechanical differences pertain to the lengthening axis, stability, and postoperative weight-bearing. Practical principles of ILNs use such as nail selection (entry point, nail length, lengthening nail problems), use of blocking screws, soft tissue releases (for nerve decompression, joint subluxation, and contractures) and physical therapy protocols are discussed.

Short or long intramedullary devices for hip fracture? A systematic review of the evidence

Trochanteric hip fractures may be fixed with either sliding hip screws or intramedullary devices. Current UK guidance is that intramedullary fixation should be used for AO/OTA 31A3 fractures but does not stipulate length of nail. We present a systematic review comparing short and long nails for these injuries in older patients.Three studies were randomized, all with methodological concerns. None demonstrated a clinically significant difference in outcome.There is no good evidence to support long over short intramedullary devices in this scenario. Evidence is required to demonstrate whether the potentially increased surgical risk confers any benefits in this group.

Three-dimensional seismic stability of slopes reinforced by soil nails

Seismic stability of slopes reinforced with soil nails has been traditionally investigated by two-dimensional limit equilibrium method. In this paper, the strength reduction method in combination with the kinematic approach of limit analysis is employed to assess the factor of safety (Fos) of slopes reinforced by soil nails using the three-dimensional rotational failure mechanism. The pseudo static approach is used to represent the seismic effects. Both the tensile failure and pull-out failure of soil nails are considered in the computations of internal energy dissipations. Comparisons are made to validate the proposed approach, which shows that the implemented approach is an efficient design tool for evaluating the factor of safety of slopes reinforced by soil nails. Parametric analysis is conducted to discuss the influence of model parameters, including nail length, nail density, soil shear strength and seismic forces, on slope stability. A set of stability charts is finally provided for fast assessments of slope safety.

Treatment of Intertrochanteric Femur Fractures with Long versus Short Cephalomedullary Nails.

Prior studies regarding indications for long vs short cephalomedullary nails in the treatment of intertrochanteric fractures had limited sample sizes and follow-up, suggesting a need for further investigation. To evaluate the association between cephalomedullary nail length and outcomes for the treatment of intertrochanteric femur fractures. Cohort study using Kaiser Permanente's Hip Fracture Registry. A total of 5526 patients who underwent surgical treatment with cephalomedullary nails for an intertrochanteric femur fracture (2009-2014) were identified: 3108 (56.2%) with long nails and 2418 (43.8%) with short nails. Cox proportional hazards model regression was used to evaluate risks of all-cause revision and revision for periprosthetic fracture. Linear regression was used to evaluate operative time, estimated blood loss, and length of stay. Propensity score weights were used in all models to balance nail groups on patient and device characteristics. All-cause revision surgery. No association was found in risk of all-cause revision (hazard ratio = 0.75, 95% confidence interval [CI] = 0.48-1.15) or revision for periprosthetic fracture (hazard ratio = 0.59, 95% CI = 0.23-1.48) for long nails compared with short nails. Use of longer nails resulted in 18.80 more minutes of operative time (95% CI = 17.33-20.27 minutes), 41.10 mL more of estimated blood loss (95% CI = 31.71-50.48 mL), and a longer hospitalization (8.4 hours; β = 0.35, 95% CI = 0.12-0.58 hours). These findings suggest that routine use of short cephalomedullary nails is safe and effective in the treatment of intertrochanteric fractures.

Risk Factors for Anterior Cortical Impingement of Short Cephalomedullary Nail in Chinese Elderly Patients with Intertrochanteric Fracture.

BackgroundAnterior cortical impingement is a common phenomenon after intramedullary fixation in Asian patients with intertrochanteric fractures. It may cause thigh pain and even fracture of the femoral shaft, which may seriously affect postoperative rehabilitation and limb function of patients. However, little was known about risk factors for anterior cortical impingement in Chinese elderly after intramedullary nailing. Hence, the aim of this study was to certify the risk factors for anterior cortical impingement treated with intramedullary nails of intertrochanteric fracture, hoping to provide suggestions for surgical treatment.Patients and MethodsA retrospective consecutive series of 94 patients who had been diagnosed as intertrochanteric fracture at our institution was included from January 2019 to November 2019. All patients were treated with intramedullary fixation and followed up for at least 6 months. Demographic, surgical and anesthesiologic information, as well as radiographic data and complications were collected and reviewed.ResultsThe ratio of anterior cortical impingement is significantly higher in female patients than that of males (80.4% vs 18.6%, P=0.041). Higher incidence of anterior cortical impingement was found in the longer intramedullary nail group, especially in females. Gender (as a female patient) and length of nail were significant risk factors for anterior cortical impingement in intertrochanteric fracture patients treated with intramedullary nail (OR =2.662, 95% CI =1.010–7.018, P=0.447; OR =1.047, 95% CI =1.016–1.079, respectively). The length of nail was a risk factor for anterior cortical impingement in female intertrochanteric fracture patients treated with intramedullary nail (OR =1.051, 95% CI =1.015–1.089).ConclusionElderly female patients with intertrochanteric fractures treated with intramedullary nails had a higher incidence of anterior cortical impingement. The length of short intramedullary nail is a risk factor for anterior cortical impingement. Patients with anterior cortical impingement may suffer serious complications.

Study of Heat Transfer Performance of Insulating Layer of Molten Salt Storage Tank

Molten salt storage tank is one of the core equipment of solar thermal power station. The design of thermal insulation layer of molten salt storage tank plays an important role in its safety and economy. It is of great commercial value and academic significance to study the heat transfer performance of the insulating layer of molten salt storage tank. In this paper, the heat transfer models of molten salt storage tank, external insulation layer and tank foundation are established. The temperature distribution and heat loss of the tank are studied. The influence of the insulation nails on the heat transfer performance of the insulation layer is analyzed. The results show that the maximum heat loss lies in insulation layer of the tank wall. Besides, the thickness of the insulating layer greatly influences the temperature drop of molten salt and the time required for steady-state heat transfer. Reasonable setting the length of insulation nail can effectively reduce the surface temperature and heat loss of the insulating layer of molten salt storage tank.

Extracorporal noninvasive acute retraction of STRYDE® for continued lengthening in cases with limited nail stroke: a technical less invasive solution to reload the STRYDE®.

With STRYDE® nails (NuVasive Specialized Orthopedics, San Diego, CA), lengthening nails for full weight-bearing during callus distraction have been available CE-certified since February 2019 in Europe. At present only antegrade femur nails and tibia nails with various lengths and diameters are available. Due to a mismatch of bone length and realizable (implantable) nail length e.g., in cases of skeletal dysplasia or achondroplastic dwarfism, it may happen that a desired lengthening of 6-8cm cannot be realized because of a nail stroke from only 5cm. Retrograde usage of antegrade piriformis nails is technically possible as an individual (off label use) procedure since so far no retrograde implants are available. A new method of surgical intervention for retraction of the STRYDE nails at the end of the nail stroke with ongoing callus distraction in patients with bilateral femoral extension under anesthesia with extracorporeal use of the fast distractor device is described in detail. It is safe and with low risk for a reload of a capacity of 3-4cm for antegrade and retrograde femoral implantation situation for the patient. The acute reload of the STRYDE nail stroke for further distraction is possible without skin incision or invasive soft tissue approaches. Application of the fast distractor extracorporeal within a few minutes is described in detail. The intervention is technically reproducible and can be performed for the proximal femur with antegrade STRYDE nails as well as for the distal femur with retrograde STRYDE nails in adult patients.

Clinical Outcomes of Intermediate-Length Cephalomedullary Nails for Intertrochanteric Femur Fracture Repair in Older Adults

Hip fracture is a major cause of morbidity and mortality in older adults. Intertrochanteric hip fractures often are treated surgically using cephalomedullary nails (CMN), in either a short or long length. Their outcomes are documented in the literature; however, outcomes of the intermediate-length CMN have not been well described. A retrospective review was conducted of older adults with intertrochanteric hip fractures that were treated with cephalomedullary nail fixation using an intermediate-length (235 mm Synthes Trochanteric Fixation® nail or 240 mm Stryker Gamma 3®) nail. Outcome data were collected during the inpatient stay and 16 months post-operatively. Seventy-seven patients met inclusion criteria and were reviewed during inpatient stay; however, only 42 had documented post-operative outcomes. Of those, two patients died post-discharge and were not included in the 16-month follow-up. Comparison of results to published literature suggested that intermediate-length nails are comparable to short-length nails with regard to time in the operating room and estimated blood loss. The rate of blood transfusion was lower and length of hospital stay was shorter than in comparable studies of both short- and long-length nails. There were no post-operative peri-prosthetic fractures in the 16-month follow-up. This rate was lower than published rates for short and long nails. The hardware failure rate (3/42, 7.1%) of intermediate-length nails was higher than comparison studies of both short- and long-length nails. Patient outcomes for intermediate-length nails were similar to outcomes of shorter length nails. Utilization of the intermediate-length nail appears to be an effective treatment option for repair of intertrochanteric femur fractures. However, direct comparison is difficult since peri-prosthetic fracture rate may increase over time and nail length and hardware failure are not defined consistently in the literature. Further study is needed with a larger sample size followed over a longer period of time to confirm our findings.

Finite Element Analysis of Traditional and New Fixation Techniques of the 3D-Printed Composite Interlocking Nail in Canine Femoral Shaft Fractures

Since the removal of a metallic interlocking nail system leaves a blank cavity inside a healed bone, bioactive and biodegradation materials have been used instead to induce bone formation and eliminate complications of the material removal procedure. The previous study presented the possibility of an interlocking nail fabrication from polylactic acid (PLA), polycaprolactone (PCL), and hydroxyapatite (HA) using 3D printing, namely fused filament fabrication (FFF), for canine diaphyseal fractures. Therefore, a finite element analysis (FEA) was used to predict the maximum principal stress of this 3D-printed composite interlocking nail to stabilize a canine femoral fracture, and the biomechanical performance was evaluated for the treatment of canine femoral shaft fractures using both traditional and new fixation techniques. Three-dimensional FEA models were created, and the composite interlocking nail was tested for implant strength and stability. Three types of canine femoral shaft fracture (proximal shaft fracture, middle shaft fracture, and distal shaft fracture) fixed by traditional and new fixation techniques, consisting of two, four, and six locking screws, were analyzed with a multilevel factorial design technique. The maximum principal stresses of the composite interlocking nail were compared with each fixation technique. According to the multilevel factorial design, gap type, fracture gap, and fixation techniques are factors that affect the maximum principal stress of the composite interlocking nail for two and four locking screws. For six locking screws, all factors, including gap type, fracture gap, nail length, and fixation techniques, significantly affect the maximum principal stress. The use of a 3D-printed composite interlocking nail system with new fixation techniques demonstrated lower maximum principal stresses than the interlocking nail system that used a traditional fixation technique. The results of this study could help orthopedic veterinary surgeons to understand the biomechanical performances of traditional and new fixation techniques. Furthermore, surgeons may use the numerical results of this analysis to choose a fixation technique based on a patient’s condition.