Introduction. Tip apex distance (TAD) is reported as a predictor for cut outs of lag screws in the treatment of intertrochanteric fractures, and surgeons are adviced to strive for TAD within 20 mm. However the definition of neck axis and the limb position of lateral radiograph are not clearly described in the original literature. We propose the refined TAD by defining these factors. The objective of this study was to analyze the interobserver agreement of this refined TAD. Materials and Method. X rays of 130 cases of unstable trochanteric fractures were used for the analysis of the refined TAD. In the refined TAD, neck axis was defined as the line between the center of femoral head and midpoint of narrowest part of the femoral neck, and lateral radiograph was taken with hip flexion 90 degrees and abduction 45 degrees. The refined TAD was independently measured by 2 experienced (observer 1,2) and 2 inexperienced (observer 3,4) orthopaedic surgeons who were trained with the new method before the measurement. Intraclass correlation coefficient (ICC [2,4]) was calculated to assess the interobserver agreement. Result. The mean refined TADs were 18.2:18.4:18.2:18.2 for observer 1:2:3:4. There was a strong correlation among all four observers (ICC 0.998, (95% CI: 0.998, 0.999). Discussion. Regardless of the clinical experience of observers, the refined TAD is a reliable tool and can be used to develop new TAD recommendations for predicting failure of fixation

Aims. Proximal femur fractures treatment can involve anterograde nailing with a single or double cephalic screw. An undesirable failure for this fixation is screw cut-out. In a single-screw nail, a tip-apex distance (TAD) greater than 25 mm has been associated with an increased risk of cut-out. The aim of the study was to examine the role of TAD as a risk factor in a cephalic double-screw nail. Methods. A retrospective study was conducted on 112 patients treated for intertrochanteric femur fracture with a double proximal screw nail (Endovis BA2; EBA2) from January to September 2021. The analyzed variables were age, sex, BMI, comorbidities, fracture type, side, time of surgery, quality of reduction, pre-existing therapy with bisphosphonate for osteoporosis, screw placement in two different views, and TAD. The last follow-up was at 12 months. Logistic regression was used to study the potential factors of screw cut-out, and receiver operating characteristic curve to identify the threshold value. Results. A total of 98 of the 112 patients met the inclusion criteria. Overall, 65 patients were female (66.3%), the mean age was 83.23 years (SD 7.07), and the mean follow-up was 378 days (SD 36). Cut-out was observed in five patients (5.10%). The variables identified by univariate analysis with p < 0.05 were included in the multivariate logistic regression model were screw placement and TAD. The TAD was significant with an odds ratio (OR) 5.03 (p = 0.012) as the screw placement with an OR 4.35 (p = 0.043) in the anteroposterior view, and OR 10.61 (p = 0.037) in the lateral view. The TAD threshold value identified was 29.50 mm. Conclusion. Our study confirmed the risk factors for cut-out in the double-screw nail are comparable to those in the single screw. We found a TAD value of 29.50 mm to be associated with a risk of cut-out in double-screw nails, when good fracture reduction is granted. This value is higher than the one reported with single-screw nails. Therefore, we suggest the role of TAD should be reconsidered in well-reduced fractures treated with double-screw intramedullary nail. Cite this article: Bone Jt Open 2024;5(6):457–463

Background. Dynamic Hip Screw (DHS) is the most frequently used implant in management of intertrochanteric femoral fractures. There is a known statistical relationship between a tip-apex distance (TAD) >25mm and higher rate of implant failure. Our aim was to analyse all DHS procedures performed in our trust from seventeen months and compare their TAD values to the acceptable standard of ≤25mm. Methods. All patients undergoing DHS between April 2020-August 2021 were identified from our theatre system. Additionally, those presenting to hospital with implant failures were included. Patient demographics, date of surgery, fracture classification (AO) and date/mode of failure were recorded. Intraoperative fluoroscopy images were reviewed to calculate TAD, screw location and neck shaft angles by two independent observers. Results. 215 patients were identified, five of which were excluded due to inadequate fluoroscopy. Failure was seen in 3.3% of the cohort (n=7), of which 71.4% had an unacceptable TAD. In total, 21 patients (10%) had TAD >25mm, of whom 12 had superiorly and 15 had posteriorly placed screws. There were no failures in patients with a TAD of <20mm whereas a TAD >30mm had 50% failure rate. Conclusion. This audit reinforces the importance of aiming for a low TAD (preferably <20mm) intraoperatively. It is also desirable to avoid superiorly and significantly posteriorly placed screws. Implications. Complex hip revision surgery in the elderly bears substantial financial implications to the NHS and, more importantly, causes prolonged morbidity to the patient. Adhering to established standards will ensure reduced implant failure and best patient care

Tip-apex distance (TAD) has long been discussed as a metric for determining risk of failure in fixation of peritrochanteric hip fractures. This study seeks to investigate risk factors including TAD for hospital readmission one year after hip fixation surgery. A retrospective review of proximal hip fractures treated with single screw intramedullary devices between 2016 and 2020 was performed at a 327 bed regional medical center. Patients included had a postoperative follow-up of at least twelve months or surgery-related complications developing within that time. 44 of the 67 patients in this study met the inclusion criteria with adequate follow-up post-surgery. The average TAD in our study population was 19.57mm and the average one year readmission rate was 15.9%. 3 out of 6 patients (50%) with a TAD > 25mm were readmitted within one year due to surgery-related complications. In contrast, 3 out of 38 patients (7.9%) with a TAD < 25mm were readmitted within one year due to surgery-related complications (p=0.0254). Individual TAD measurements, averaging 22.05mm in patients readmitted within one year of surgery and 19.18mm in patients not readmitted within one year of surgery were not significantly different between the two groups (p=0.2113). Our data indicate a significant improvement in hospital readmission rates up to one year after hip fixation surgery in patients with a TAD < 25mm with a decrease in readmissions of over 40% (50% vs 7.9%). This result builds upon past investigations by extending the follow-up time to one year after surgery and utilizing hospital readmissions as a metric for surgical success. With the well-documented physical and financial costs of hospital readmission after hip surgery, our study highlights a reduction of TAD < 25mm as an effective method of improving patient outcomes and reducing financial costs to patients and medical institutions

Lag screw cut-out is a serious complication of dynamic hip screw fixation in trochanteric hip fractures. Lag screw position is recognised as a crucial factor influencing the occurrence of lag screw cut-out. We propose a modification of the Tip Apex Distance (TAD) and hypothesize that it could enhance the reliability of predicting lag screw cut-out in these injuries. A retrospective study of hip fracture cases was conducted from January 2018 to July 2022. A total of 109 patients were eligible for the final analysis. The modified TAD was measured in millimetres, based on the sum of the traditional TAD in the lateral view and the net value of two distances in the anteroposterior (AP) view. The first distance is from the lag screw tip to the opposite point on the femoral head along the lag screw axis, while the second distance is from that point to the femoral head apex. The first distance is a positive value, whereas the second distance is positive if the lag screw is superior and negative if it is inferior. Receiver operating characteristic (ROC) curve analysis was used to assess the reliability of various parameters for evaluating the lag screw position within the femoral head. Factors such as reduction quality, fracture pattern according to the AO/OTA classification, TAD, Calcar-Referenced TAD, Axis Blade Angle, Parker’s ratio in the AP view, Cleveland Zone 1, and modified TAD were statistically associated with lag screw cut-out. Among the tested parameters, the novel parameter exhibited 90.1% sensitivity and 90.9% specificity for predicting lag screw cut-out at a cut-off value of 25 mm, with a p-value < 0.001. The modified TAD demonstrated the highest reliability in predicting lag screw cut-out. A value of 25 mm may potentially reduce the risk of lag screw cut-out in trochanteric hip fractures

Objectives. Different criteria for assessing the reduction quality of trochanteric fractures have been reported. The Baumgaertner reduction quality criteria (BRQC) are relatively common and the Chang reduction quality criteria (CRQC) are relatively new. The objectives of the current study were to compare the reliability of the BRQC and CRQC in predicting mechanical complications and to investigate the clinical implications of the CRQC. Methods. A total of 168 patients were assessed in a retrospective observational study. Clinical information including age, sex, fracture side, American Society of Anesthesiologists (ASA) classification, tip-apex distance (TAD), fracture classification, reduction quality, blade position, BRQC, CRQC, bone quality, and the occurrence of mechanical complications were used in the statistical analysis. Results. A total of 127 patients were included in the full analysis, and mechanical complications were observed in 26 patients. The TAD, blade position, BRQC and CRQC were significantly associated with mechanical complications in the univariate analysis. Only the TAD (p = 0.025) and the CRQC (p < 0.001) showed significant results in the multivariate analysis. In the comparison of the receiver operating characteristic curves, the CRQC also performed better than the BRQC. Conclusion. The CRQC are reliable in predicting mechanical complications and are more reliable than the BRQC. Future studies could use the CRQC to assess fracture reduction quality. Intraoperatively, the surgeon should refer to the CRQC to achieve good reduction in trochanteric fractures. Cite this article: Bone Joint Res 2019;8:502–508

Aims. To develop a core outcome set of measurements from postoperative radiographs that can be used to assess technical skill in performing dynamic hip screw (DHS) and hemiarthroplasty, and to validate these against Van der Vleuten’s criteria for effective assessment. Methods. A Delphi exercise was undertaken at a regional major trauma centre to identify candidate measurement items. The feasibility of taking these measurements was tested by two of the authors (HKJ, GTRP). Validity and reliability were examined using the radiographs of operations performed by orthopaedic resident participants (n = 28) of a multicentre randomized controlled educational trial (ISRCTN20431944). Trainees were divided into novice and intermediate groups, defined as having performed < ten or ≥ ten cases each for DHS and hemiarthroplasty at baseline. The procedure-based assessment (PBA) global rating score was assumed as the gold standard assessment for the purposes of concurrent validity. Intra- and inter-rater reliability testing were performed on a random subset of 25 cases. Results. In total, 327 DHS and 248 hemiarthroplasty procedures were performed by 28 postgraduate year (PGY) 3 to 5 orthopaedic trainees during the 2014 to 2015 surgical training year at nine NHS hospitals in the West Midlands, UK. Overall, 109 PBAs were completed for DHS and 80 for hemiarthroplasty. Expert consensus identified four ‘final product analysis’ (FPA) radiological parameters of technical success for DHS: tip-apex distance (TAD); lag screw position in the femoral head; flushness of the plate against the lateral femoral cortex; and eight-cortex hold of the plate screws. Three parameters were identified for hemiarthroplasty: leg length discrepancy; femoral stem alignment; and femoral offset. Face validity, content validity, and feasibility were excellent. For all measurements, performance was better in the intermediate compared with the novice group, and this was statistically significant for TAD (p < 0.001) and femoral stem alignment (p = 0.023). Concurrent validity was poor when measured against global PBA score. This may be explained by the fact that they are measuring difference facets of competence. Intra-and inter-rater reliability were excellent for TAD, moderate for lag screw position (DHS), and moderate for leg length discrepancy (hemiarthroplasty). Use of a large multicentre dataset suggests good generalizability of the results to other settings. Assessment using FPA was time- and cost-effective compared with PBA. Conclusion. Final product analysis using post-implantation radiographs to measure technical skill in hip fracture surgery is feasible, valid, reliable, and cost-effective. It can complement traditional workplace-based assessment for measuring performance in the real-world operating room . It may have particular utility in competency-based training frameworks and for assessing skill transfer from the simulated to live operating theatre. Cite this article: Bone Joint Open 2020;1-9:594–604

Introduction. The vast majority of intertrochanteric fractures treated with cephalomedullary nails (CMN) will heal. Occasionally even though bony union occurs excessive lag screw sliding can cause persistent pain and soft tissue irritation and return to surgery for hardware removal. The purpose of this study was to evaluate if fracture stability, lag screw tip-apex distance (TAD), and quality of reduction have any impact excessive lag screw sliding and potential cutout. Methods. As part of our level one trauma center's institutional hip fracture registry, a retrospective analysis identified 199 intertrochanteric fractures fixed with CMN between 2009 and 2015 with follow up to union or a minimum of three months. The mean follow-up was 22 months (3 to 94 months). Mean patient age was 75 years (50 to 97 years) and 72% were women. Postoperative radiographs were used to measure the TAD, quality of reduction, neck-shaft angle (NSA), and lateral lag screw prominence. Follow-up radiographs were reviewed to assess fracture union, translation, and progression of lateral lag screw prominence. Complications and reoperations were recorded. Results. The average lag screw sliding was 5±5 mm. Excessive lag screw sliding (defined as > 10 mm; one standard deviation above the mean) was present in 12% of patients. Lag screw sliding was more common in unstable fracture patterns (21% vs. 5%, p<0.01) and patients with calcar fracture gapping > 4 mm (26% vs. 4%, p<0.01). Lag screw sliding was not associated with age (p=0.9), sex (p=0.4), TAD (p=0.3), implant (p=0.8), distal interlocking screws (p=0.3), or NSA (p=0.2). There were seven (3%) patients with prominent lag screws that required removal. These patients experience more lag screw sliding than those that did not require removal (9 mm vs. 5 mm, p<0.01). The average TAD was 17±5 mm. 15 (7%) of patients had TAD of 25 mm or more. There were 2 cutouts (1%). The average TAD was larger in the cutout group (26 vs. 17 mm, p<0.01). Conclusion. In this series, the incidence of cutout was low and associated with a larger tip-apex distance. Excessive lag screw sliding was associated with unstable fracture patterns, calcar fracture gapping, and more reoperations for symptomatic hardware. Careful attention to calcar fracture reduction may minimize excessive lag screw sliding

Introduction: Hip fractures are a massive problem in an ageing population with 7–21 million predicted world-wide by 2025. The stabilization of intertrochanteric fractures reduces morbidity, mortality and allows mobilization. The treatment of these fractures has evolved over the past 50 years to the Sliding hip screw and plate, and intramedullary devices Current evidence suggests that the SHS systems are superior in stable fracture patterns and intramedullary devices are superior in unstable fracture patterns such as reverse oblique fractures or subtrochanteric fractures. Accurate implant positioning will prevent failure and the associated morbidity and mortality. The most frequent failure is due to cut out of the screw through the femoral head due to poor positioning. Cut out is directly correlated with tip apex distance (TAD). A TAD < 25mm has been to shown to be key to preventing cut out irrespective of fixation device. Aims: The aims of this audit were to review TAD in proximal femoral fractures stabilized with a SHS system at one hospital to ensure:. TAD is < 25mm. To establish whether there was a correlation between TAD and surgeon grade or fracture type. To establish positions of screws on both radio graphs. To ensure SHS are used in the correct fracture types. Results: Radiographs over a period of 1 year where reviewed. There were 86 cases of SHS fixation. 72% of cases were female (62:24). The mean age was 84(65 to 97). The mean preoperative delay before surgery was 4.5 range (0 –15). 13% of cases (11/86) had no postoperative radiographs either digitally or hard copies stored in the notes. The mean value of TAD was 20.8mm (Std dev 6.89). There was no correlation between fracture patterns and TAD, or surgeon grade and TAD. However there was a trend for higher TAD in inexperienced surgeons and in more complex fracture patterns. The majority of cases were operated on by Registrars 67%, Staff grade 15%, Research fellows 9%, SHOs 6% and Consultant grades 3%. Registrars achieved Centre–Centre positions in 62% of cases with staff grade 47% of cases. The majority of SHS were performed for Types 2 and 4 according to Jensen & Michaelson classification. SHS implants were used in one subtrochanteric fracture and zero reverse oblique fractures. 21 cases had a TAD> 25mm and one of these has gone on to failure, requiring THR. Conclusion: The mean TAD was within recommendations and there was no correlation between surgeon grade, fracture pattern and TAD. The positioning of screws corresponds closely to published data and remains acceptable as does the use of SHS devices. Both the preoperative delay and number of inadequate radiographs is unacceptable and needs improvement

Awareness that minimising tip apex distance (TAD) when inserting a sliding hip screw reduces the risk of screw cut out is important for orthopaedic trainees. The advent of the Picture Archive and Communication System (PACS) has made the accurate measurement of TAD from x-rays and image intensifier films much easier. This study was to determine whether TAD would be reduced if a surgeon knew that his performance was being continually monitored. 31 consecutive cases of sliding hip screw insertion by a single group of surgeons were identified and the TAD measured. The mean TAD was 16.11mm (8.87mm-25.47mm). The same surgeons were then re-educated as to the importance of the TAD and informed that their results would be monitored and discussed. The next 34 consecutive cases were collected prospectively. The mean TAD in these cases was 13.83mm (6.72mm-21.51mm). There was a significant difference between the TAD for the two groups using the two-tailed t-test (p=0.034). There was one implant failure in the pre education group and none in the post education group. These results suggest that awareness of surveillance improves surgical performance even if the importance of the variable being assessed is already known

It is widely accepted that a tip apex distance of greater than 25mm is associated with dynamic hip screw (DHS) failure and cut-out. The aim was to devise an accurate and easy method for calculation of DHS tip apex distance (TAD) from intraoperative imaging using the tools available on Kodac Picture Archiving and Communications System. This method was applied to all patients treated with a DHS for intertrochanteric hip fracture during a six month period. Any subsequent radiographs were assessed for evidence of failure within 18 months. The TAD was calculated using a modification of a previously described method using a similar imaging system (Johnston et al, Injury 2008) which has been shown to be accurate and reproducible. Scaling was based on the 12.5mm thread diameter of all Synthes (Switzerland) DHS screws. 60 patients underwent a DHS during the study. Nine patients were excluded who had an additional method of fixation or an intracapsular fracture. Four patients had insufficient xrays for analysis. Data was gathered for 47 patients and showed a mean TAD of 17mm (range 8.2–30.6mm). Three patients had a TAD greater than 25mm. 22 patients had a post-operative xray within 18 months. There were two cut-outs identified and both were from patients with a TAD of greater than 25mm (25.7 and 30.6mm). No incidences of implant failure or complications were identified for patients with acceptable TADs. 93.6% of screws were therefore inserted satisfactorily. Two out of the three patients with a TAD greater than 25mm had xray evidence of screw cut-out. This study supports previous evidence that a DHS lag screw should be positioned with a TAD within 25mm and a distance greater than this is associated with screw cut-out. TAD can be easily calculated using intraoperative xrays and scaled using the screw itself

This multicentre audit assessed the total Tip Apex Distance (TAD) of sliding hip screws for intertrochanteric hip fractures in the 3 fracture hospitals in Northern Ireland (Ulster Hospital, Royal Victoria Hospital & Altnagelvin Hospital). Patient demographics and anaesthetic information was also reviewed. A sample of 140 patients with adequate screening films (39 UHD, 50 RVH & 51 Altnagelvin) were selected. The TAD was measured on AP & lateral screening films and compared to the standard of 25mm or less (total in 2 views) as recommended by Baumgaertner et al (JBJS (Am) 1995). All 3 hospitals had an average of under 25mm (22.1, 19.9 & 19.6mm respectively) with overall average of 20.4mm, and a TAD of 25mm or less was achieved in 66.7%, 82% & 80.4% in respective hospitals (77.1% of patients overall). No patients were readmitted due to cut-out, despite 22.9% of patients having a TAD greater than 25mm. Among patients with TAD over 25mm the average TAD was 30.1mm. Demographics showed a 77.8% of patients to be female, with a slight predominance of left sided injuries. Most patients were of ASA grading 2–3. Anaesthetic method preferences varied between hospitals. Patients with TAD over 25mm were not significantly different from those with TAD of 25mm or less in age, gender, ASA or operated side

Intertrochanteric fractures are common, accounting for nearly 30% of all fracture related admissions. Some have suggested that these fractures should be treated in community hospitals so as not to tax the resources of Level One trauma centers. Since many factors predictive of fixation failure are related to technical aspects of the surgery, the purpose of this study was to compare radiographic parameters after fixation comparing trauma fellowship trained surgeons to non-fellowship trained community surgeons to see if these fractures can be treated successfully in either setting. Using our hospital system's trauma database, we identified 100 consecutive patients treated with cephalomedullary nails by traumatologists, and 100 consecutive patients treated by community surgeons. Quality of reduction, neck shaft angle (NSA), tip-to apex distance (TAD) were compared. The mean TAD for the trauma group was 10mm compared to 21mm for the community group (p<0.001). The mean postoperative NSA for the trauma group was 133 degrees compared to 127 degrees for the community group (p<0.001). The mean difference in the NSA of the fractured side compared to the normal hip was 2.5 degrees of valgus in the trauma group compared to 5 degrees of varus for the community group (p<0.001). There were 93 good reductions in the trauma group compared to 19 in the community group (p<0.001). There were no poor reductions in the trauma group and 49 poor reductions in the community group (p<0.001). Fellowship trained traumatologists achieved significantly more accurate reductions and implant placement during cephalomedullary nailing of intertrochanteric hip fractures

A tip-apex distance (TAD) greater than 25 mm is a strong predictor of screw cut-out in patients with intertrochanteric femoral fracture treated with a dynamic hip screw (DHS). We aim to show you a simple and reliable way to check this. By calculating the sum of the distance from the tip of the screw to the apex of the femoral head on anteroposterior and lateral views the TAD is found. X-rays often have magnification errors and therefore measuring tools in digital x-ray systems will be inaccurate. The original method of calculating the TAD uses the known diameter of the screw to avoid magnification errors. We found that due to the no-cylindrical shape of the screw shaft there is potential of an inaccurate measurement. By using the distance across the highest points of the thread a more accurate TAD can be calculated. The distance across the highest points of the threads in all three of the most commonly used DHSs in the UK is 13 mm. If the measured distance from the tip of the screw to the apex of the femoral head in both the anteroposterior and lateral views is less than the measured distance across of the treaded diameter of the screw then the surgeon knows the TAD is less than 26 mm. This method can be used intraoperatively to check the TAD by looking at the fluoroscopy images in these two views

Intra-operative Tip-Apex Distance (TAD) estimation optimises dynamic hip screw (DHS) placement during hip fracture fixation, reducing risk of cut-out. Thread-width of a standard DHS screw measures approximately 12.5 millimetres. We assessed the effect of introducing screw thread-width as an intra-operative distance reference to surgeons. The null hypothesis was that there were no differences between hip fracture fixation before and after this intervention. Primary outcome measure was TAD. Secondary outcome measures included position of the screw in the femoral head, quality of reduction, cut-out and surgeon accuracy of estimating TAD. 150 intra-operative DHS radiographs were assessed before and after introducing screw thread-width distance reference to surgeons. Mean TAD reduced from 19.37mm in the control group to 16.49mm in the prospective group (p=<0.001). The number of DHS with a TAD > 25mm reduced from 14% to 6%. Screw position on lateral radiographs was significantly improved (p=0.004). There were no significant differences in screw position on antero-posterior radiographs, quality of reduction, or rate of cut-out. Significant improvement in accuracy (p=0.05) and precision (p=0.005) of TAD estimation was demonstrated. Awareness and use of screw-thread width improves estimation and positioning of a DHS screw in the femoral head during fixation of hip fractures

Purpose: Purpose of the study is to compare the changing Tip Apex Distance (TAD) and therefore the cut out development risk during fracture healing in two different types of implant. Materials and Methods: 166 patients with intertrochanteric femur fracture were operated with proximal femoral nail between the years 1999 and 2006 in our clinic. 117 patients with avaible radiological data were studied. Group I defined as PFN, had 90 patients. Median age was 74.2 (25–93) years, 44 female and 46 male. Grup II defined as PFN-A had 27 patients. Median age was 75 (33–88) years, 18 females, 9 males. The mean of following time of patients was 48 months (12–84 months). We measured in AP radiograph the tip-apex distance (TAD) both of early postop and fracture healing time. Results: In group I change in TAD was observed in 70 (%77.7) patients. Average TAD change rate was %29 (%4–%230). In group II, change in TAD was observed in 15 (%55.6) patients, and the average TAD change rate was %12 (%5–%40). Among Group I, 3 patients had a revision surgery with cut-out complications (%3.3). Among Group II no patient had cut out complication. Discussion: While cut out was developed in 3 PFN patients, no cut-out was observed in any of PFN-A patients. Among the patients without cut-out development, 77.7 % of PFN patients and 55.6 % of PFN-A were under cut out risk. Average TAD change rate was 29% in PFN Group whereas 12% in PFN-A Group. When TAD change rates are considered, no cut-out was determined in PFN-A Group while its development risk was lower. When we investigate the cut out complication, the 3 cut out complications (%3.3) was seen in PFN. PFN-A group had no cut out complications

Failure of cephalomedullary fixation for proximal femur fractures is an uncommon event associated with significant morbidity to the patient and cost to the healthcare system. This institution changed nailing system from the PFNA (DePuy Synthes) to InterTan (Smith and Nephew) in February 2020. To assess for non-inferiority, a retrospective review was performed on 247 patients treated for unstable proximal femur fractures (AO 31 A2; A3). Patients were identified through manual review of fluoroscopic images. Stable fracture patterns were excluded (AO 31 A1). Pre/post operative imaging, demographic data, operative time and ASA scores assessed. Internal/external imaging and national joint registry data were reviewed for follow up. No significant difference was found in overall failure rate of PFNA vs InterTan (4.84% vs 3.23%; p = 0.748). Overall, short nails were more likely to fail by cut-out than long nails (7.5% vs 1.2%; p = 0.015). Nails which failed by varus cut-out had a higher tip/apex distance (TAD) (26.2mm vs 17.0mm; p < 0.001). Of concern, varus cut-out occurred in two InterTan nails with TAD of <25mm. The PFNA enjoyed a shorter operative time for both the short (59.1 vs 71.8 mins; p = 0.022) and long nails (98.8 vs 114.3 mins; p = 0.016) with no difference in 120-day survival rate. Overall failure rates of the PFNA and InterTan nailing systems were comparable. However, the failure rate of short nails in this study is concerning. Using long nails with a lag screw design for unstable intertrochanteric femoral fractures may reduce failure rates. Cumulative frequency analysis suggests stringent tip-apex distances of less than 21mm may reduce failure rates in lag-screw design cephulomedullary nails. This dataset suggests that unstable intertrochanteric fractures may be more reliably managed with a long cephalomedullary device

Subtrochanteric femoral fractures are a subset of hip fractures generally treated with cephalomedullary nail fixation\[1\]. Single lag screw devices are most commonly-used, but integrated dual screw constructs have become increasingly popular\[2,3\]. The aim of this study was to compare outcomes of fixation of subtrochanteric femoral fractures using a single lag screw (Gamma3 nail, GN) with a dual screw device (InterTAN nail, IN). The primary outcome was mechanical failure, defined as lag screw cut-out, back-out, nail breakage or peri-implant fracture. Consecutive adult patients (18yrs) with subtrochanteric femoral fracture treated in a single centre were retrospectively identified using electronic records. Patients that underwent surgical fixation using either a long GN (2010–2017) or IN (2017–2022) were included. Medical records and radiographs were reviewed to identify complications of fixation. Cox regression analysis was used to determine the risk of mechanical failure and secondary outcomes by implant design. Multivariable regression models were used to identify predictors of mechanical failure. The study included 622 patients, 354 in the GN group (median age 82yrs, 72% female) and 268 in the IN group (median age 82yrs, 69% female). The risk of any mechanical failure was increased two-fold in the GN group (HR 2.44 \[95%CI 1.13 to 5.26\]; _p=0.024_). Mechanical failure comprising screw cut-out (_p=0.032_), back-out (_p=0.032_) and nail breakage (_p=0.26_) was only observed in the GN group. Technical predictors of failure included varus >5° for cut-out (OR 19.98 \[2.06 to 193.88\]; _p=0.01_), TAD;25mm for back-out (8.96 \[1.36 to 58.86\]; p=0.022) and shortening 1cm for peri-implant fracture (7.81 \[2.92 to 20.91\]; _p=<0.001_). Our results demonstrate that an intercalated screw construct is associated with a lower risk of mechanical failure compared with the a single lag screw device. Intercalated screw designs may reduce the risk of mechanical complications for patients with subtrochanteric femoral fractures

Background. Hip fractures cause significant morbidity and mortality, affecting 70,000 people in the UK each year. The dynamic hip screw (DHS) is used for the osteosynthesis of extracapsular neck of femur fractures, a procedure that requires complex psychomotor skills to achieve optimal lag screw positioning. The tip-apex distance (TAD) is a measure of the position of the lag screw from the apex of the femoral head, and is the most comprehensive predictor of cut-out (failure of the DHS construct). To develop these skills, trainees need exposure to the procedure, however with the European Working Time Directive, this is becoming harder to achieve. Simulation can be used as an adjunct to theatre learning, however it is limited. FluoroSim is a digital fluoroscopy simulator that can be used in conjunction with workshop bones to simulate the first step of the DHS procedure (guide-wire insertion) using image guidance. This study assessed the construct validity of FluoroSim. The null hypothesis stated that there would be no difference in the objective metrics recorded from FluoroSim between users with different exposure to the DHS procedure. Methods. This multicentre study recruited twenty-six orthopaedic doctors. They were categorised into three groups based on the number of DHS procedures they had completed as the primary surgeon (novice <10, intermediate 10≤x<40 and experienced ≥40). Twenty-six participants completed a single DHS guide-wire attempt into a workshop bone using FluoroSim. The TAD, procedural time, number of radiographs, number of guide-wire retires and cut-out rate (COR) were recorded for each attempt. Results. A significant construct effect was seen for TAD and COR between novice and other users (p < 0.05). The intermediate and experienced users were not significantly different for these metrics. For all other metrics, experienced users had the highest score, contrary to expectation. Conclusion. FluoroSim was able to separate novice users from other cohorts for the two clinically significant outcome metrics. We can therefore partially reject the null hypothesis as construct validity was present for TAD and COR. We have demonstrated that FluoroSim has the potential to be a useful adjunct when learning the psychomotor skills needed for the DHS procedure away from theatre

Introduction Intertrochanteric fractures are common and represent a major source of morbidity and mortality. As with all orthopaedic implants a DHS can fail. One of the most important predictors of failure has been shown to be the Tip-Apex Distance (TAD). An audit was carried to assess the following:. What was our rate of cut out and implant failure?. Where we achieving an acceptable screw position and TAD?. Was there any difference between TAD and grade of surgeon?. Methods An audit of the case notes and x-rays of 54 consecutive patients with hip fractures, treated with DHS, within a twelve-month period were reviewed. Demographic data, grade of surgeon, fracture stability, DHS position, mortality and implant failure were assessed. Findings Our rate of failure was 2 out of 54 patients, 3.7%. Both of the patients that failed had a TAD of greater than 20mm, and none of the patients with a TAD below 20mm required further surgery. There was no statistical correlation between TAD and grade of operating surgeon. Recommendations It is paramount importance to ensure that the basic principles of DHS position are well taught to surgical trainees in order to reduce the risk of failure. Following DHS fixation, patients should be followed up for a minimum of 3 months until evidence of radiographic union is evident. DHS failure rates and screw positions should be constantly audited to ensure that failure rates are minimised