A new fluoroscopic view for evaluation of anteromedial cortex reduction quality during cephalomedullary nailing for intertrochanteric femur fractures: the 30° oblique tangential projection

Anteromedial cortical support reduction of intertrochanteric fractures-A review

The intertrochanteric fracture is a common fragility fracture typically resulting from low-energy falls. The functional outcome of intertrochanteric fractures is closely linked to the patient's underlying physical condition, intraoperative procedures, and postoperative complications. In terms of surgery, while timely surgery and appropriate internal fixation have demonstrated favorable outcomes, attention to intraoperative reduction is crucial. In recent years, there have been further developments in the evaluation of reduction of intertrochanteric fractures, particularly in the anteromedial cortical reduction, and these advances have been further scientifically elucidated in terms of their ability to provide stable fracture reduction and resist loss of reduction. In order to gain a comprehensive understanding of the anteromedial cortex theory, this article reviewed the anatomy, related theoretical progress, and controversies in recent years.

[Standard radiographic images in cephalomedullary nailing fixation for intertrochanteric femoral fractures]

Objective

To review and summarize the projections of radiographic images during cephalomedullary nailing fixation for intertrochanteric femoral fractures, and to propose a set of three projections as standard requirement in immediate postoperative fluoroscopy.

Methods

Papers on intertrochanteric femoral fractures treated with cephalomedullary nailing fixation that published in a three-year period of 2021-2023 in four leading English orthopedic trauma journals were searched in PubMed. The presented radiographic pictures were identified and scrutinized as whether they were in standard anteroposterior and/or lateral projections of the implanted nails. The nonstandard presence percentage was calculated. Combined with clinical experience, the standard anteroposterior and lateral perspective images of femoral neck, the current situation of radiographic imaging in the operation of cephalomedullary nails, the literature analysis of nonstandard images, the impact of limb rotation on image interpretation, and the characteristics of anteromedial 30° oblique perspective were summarized and analyzed.

Results

The presence of nonstandard radiographic pictures is 32.1% in anteroposterior view and 69.2% in lateral view in leading orthopedic trauma journals. In cephalomedullary nailing fixation operation of intertrochanteric femoral fractures, it is reasonable to use the radiographic images of the implanted nails to represent the fractured head-neck, as the head-neck implant (lag screw or helical blade) is aimed to put into centrally in femoral head in lateral projection. Limb rotation or nonstandard projections produced distortion of images, which interfers the surgeons' judgement of fracture reduction quality and the measurement of implant position parameters in femoral head (such as neck-shaft angle and tip-apex distance), and finally lead to a meaningless comparison with the accurate normal value. The 30° anteromedial oblique view from the true lateral (set as 0°) is a tangential projection of the cortices at the anteromedial inferior corner, which gives a clear profile for the determination of cortical apposition status and mechanical support. It is essential to get firstly the true standard lateral fluoroscopy of the nail (shown as a line), then rotate the C-arm to 90° and 30° to get anteroposterior and anteromedial oblique views, and use these three immediate postoperative radiographies as the baseline for evaluation of operative quality and follow-up comparisons.

Conclusion

As for real-time monitoring of surgical steps, intraoperative fluoroscopy follows the "Enough is Good" principle, but as for immediate postoperative data storage and basis for operative quality evaluation and baseline for follow-up comparison, it is recommended to obtain a set of three standard radiographic pictures in anteroposterior, true lateral, and 30° anteromedial oblique fluoroscopic projections.

Anteromedial Cortical Support in Reduction of Trochanteric Hip Fractures: From Definition to Application

➤ The concept of anteromedial cortical support (AMCS) serves as valuable guidance for the intraoperative reduction of trochanteric hip fractures.➤ Positive medial cortical support (MCS) and positive or neutral anterior cortical support (ACS) are desirable. Some evidence has suggested that positive MCS is potentially superior to neutral MCS.➤ Experimental studies underscore the vital importance of the anteromedial wall and reveal why positive MCS potentially outperforms neutral MCS.➤ Incorporating the AMCS concept, the Chang reduction quality criteria (CRQC) are a reliable alternative approach to evaluate the reduction quality of trochanteric hip fractures.

Biomechanical evaluation of a modified intramedullary nail for the treatment of unstable femoral trochanteric fractures

Background

The Proximal Femoral Nail Antirotation (PFNA) device is the most commonly used implant to fix unstable femoral trochanteric fractures (UFTFs), but it has a relatively high incidence of complications. Due to this factor, the modified intramedullary nail (MIN) was created to treat patients with UFTFs. The aim was to exhibit the MIN and make a comparison with PFNA and InterTAN using biomechanical methods.

Methods

An adult UFTF model was developed using Mimics software. The PFNA, InterTAN nail, and MIN models were drawn referring to the corresponding parameters and installed in the fracture models. Vertical, anteroposterior (AP) bending, and torsion loads of the femoral head were set in advance and loaded onto the fracture models. The value of maximal displacement and von Mises stress was evaluated via finite element analysis (FEA).

Results

The MIN model had smaller values for maximal displacement than that of the PFNA model, and the increase in displacement was less pronounced for the MIN compared to PFNA under increasing vertical loads. For the indicator of von Mises stress, the MIN model showed lower stress compared with the PFNA model in vertical loads ranging from 300 N to 2100 N. Except for the maximal stress at implants under AP bending loads, the MIN demonstrated the most superior biomechanical properties under AP bending and torsional loads.

Conclusion

The MIN offered obvious advantages in terms of mechanical stability and stress distribution among the three studied implants, providing a promising implant option for patients with UFTFs.

Anterior Malreduction is Associated With Lag Screw Cutout After Internal Fixation of Intertrochanteric Fractures

BACKGROUND

Lag screw cutout is a devastating complication after internal fixation of an intertrochanteric fracture. Although the tip-apex distance (TAD) is known to be associated with this complication, another factor we thought was potentially important-fracture reduction on an oblique lateral view-has not, to our knowledge, been explored.

QUESTIONS/PURPOSES

(1) Is a well-reduced fracture position on an oblique lateral view after internal fixation of intertrochanteric fracture associated with a lower odds of postoperative cutout, independently of the TAD? (2) Is postoperative sliding of the lag screw after fixation associated with postoperative cutout?

METHODS

Patients with intertrochanteric fractures who were at least 65 years old and who had been treated with internal fixation in one of six facilities between July 2011 and December 2017 were included. All patients in the study group had lag screw cutout, and controls were selected by risk-set sampling of age-matched and sex-matched patients using a ratio of 4:1 for patients from each hospital. Of the 2327 intertrochanteric fractures, there were 36 patients (0.02 per person-year), with a mean age of 85 years; 89% (32) were women. In the control group, there were 135 controls. There was no difference in age or sex between the two groups. Sagittal reduction was evaluated using an immediate postoperative oblique lateral radiograph (anterior malreduction versus anatomic reduction or posterior malreduction). The association between anterior malreduction and the odds of cutout was estimated by conditional logistic regression analysis with the TAD and interaction between the TAD and the reduced position as covariates. As a sensitivity analysis, we estimated whether sliding within 2 weeks postoperatively was associated with cutout.

RESULTS

After controlling for the potentially confounding variables of age and sex, we found that anterior malreduction was independently associated with a higher odds of cutout compared with anatomic reduction or posterior malreduction (adjusted OR 4.2 [95% CI 1.5 to 12]; p = 0.006). There was also an independent association between cutout and larger TAD (≥ 20 mm) (adjusted OR 4.4 [95% CI 1.4 to 14]; p = 0.01). However, the association between cutout and reduction was not modified by the TAD (adjusted OR of interaction term 0.6 [95% CI 0.08 to 4]; p = 0.54). Postoperative sliding ≥ 6 mm within 2 weeks was associated with higher odds of cutout after adjusting for age and sex (adjusted OR 11 [95% CI 3 to 40]; p < 0.001).

CONCLUSION

In patients older than 65 years with intertrochanteric fractures, anterior malreduction on a lateral oblique view was associated with much greater odds of postoperative cutout than anatomic reduction or posterior malreduction. Because anterior malreduction is within the surgeon's control, our findings may help surgeons focus on intraoperative reduction on an oblique lateral view to prevent cutouts. Although this factor is a reliable indicator, the results should be applied to cephalomedullary nails, because there was only one patient with cutout among those with sliding hip screws. Because this study was conducted in a homogenous Japanese population, future studies should focus on the association between anterior malreduction and cutout in people of different ethnicities, adjusting for confounding factors such as implant type and surgeon level.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Accuracy of radiographic projections to guide cephalic screw position in pertrochanteric fracture: a cadaveric study

PURPOSE

The aim of this study was to evaluate the relationship between the Löwenstein Lateral view and the True Lateral view for the positioning of the cephalic hip screw, through a cadaveric study.

MATERIALS AND METHODS

We placed two Kirschner wires in eight femur specimens using an Antero-Posterior view, Löwenstein Lateral view and True Lateral view. The distances between the Kirschner wires and the anterior, posterior, superior and inferior cortex were measured in all projections. The head of the femur was then sectioned, and the same macroscopic distances were measured. Finally, we could calculate the accuracy of the two radiographic lateral projections.

RESULTS

When the Kirschner wire was placed in the center of the head using the Antero-Posterior and the True Lateral view, the accuracy of Antero-Posterior view was 0.9705 while the accuracy of True Lateral view and Löwenstein Lateral view was 1.1479 and 1.1584, respectively. When the Kirschner wire was placed superior on the Antero-Posterior and centrally on the True Lateral view, the accuracy of Antero-Posterior view was 0.9930 while the accuracy of True Lateral view and Löwenstein Lateral view was 1.1159 and 0.7224, respectively.

CONCLUSION

When the Kirschner wire was positioned proximal in Antero-Posterior view and central in True Lateral view, only the True Lateral view showed high accuracy.

Optimizing post-operative imaging: a retrospective cohort study comparing two methods of lateral hip radiography after cephalomedullary nail surgery

BACKGROUND

Currently, there is no consensus on the most appropriate technique for obtaining lateral hip radiographs after cephalomedullary nail (CMN) surgery. The aim of this study was to investigate the distribution of two commonly used postoperative lateral hip radiographic methods (classic lateral view and modified lateral view) and try to find out which one is better suited for this situation.

METHODS

A retrospective analysis was conducted on 146 patients who underwent surgical fixation for extracapsular hip fractures between January 2018 and June 2022. The main outcome measured was the angle between the straight part of the CMN and the lag screw/blade on hip lateral X-rays (CMNA). The lateral hip radiographs were categorized into two groups based on different lateral hip radiographic methods. CMNA, patient age, gender, fracture classification based on the 2018 AO classification, nail length (short/long), surgical side (left/right), height, weight, BMI, preoperative waiting time, postoperative imaging interval were collected and compared between the two groups.

RESULTS

The distribution trend of CMNA significantly differs between two types of hip joint lateral radiographic methods. Specifically, the classic lateral method exhibits a significantly bimodal and skewed distribution with a median (p25, p75) of -21.6° (-31.2°, -8°), whereas the modified lateral method presents a normal distribution with a mean ± SD of +7.57° ± 14.4°. The difference in the Mean Rank between the classic (47.10) and the modified (102.96) lateral methods is statistically significant (P < 0.001).

CONCLUSIONS

The CMNA method is an excellent tool for studying the lateral distribution.We recommend using the modified lateral view as the preferred option for obtaining lateral hip radiographs after CMN surgery due to its superior distribution of CMNA and greater patient-friendliness.

Relative instability ratios of bone wall defects in trochanteric hip fractures: A finite element analysis

Background: For decades, medial and lateral wall fragments of trochanteric hip fractures were considered two pivotal factors that could influence the stability of postoperative femur-implant complex. However, most studies seemed to misunderstand the concept of the posteromedial fragment and equated it with the medial wall, which overlooked vital roles of the anteromedial wall. Roles of the posterior coronal bone fragment were also highlighted in some research. However, influences of the bone walls above the trochanteric fracture instability are yet to be investigated and quantified by means of finite element analysis. Methods: Eight trochanteric fracture fixation models with different wall defects were constructed. Outcome indicators were the von Mises stress of the implant models, the maximum/minimum principal strain, the risky tensile/compressive volume and the volume ratios of the bone models, the femoral head vertex displacement, and the fracture surface gap. Based on these indicator values, the relative instability ratios were computed. Results: Outcome indicators, absolute values, and nephograms of all models showed the same upward and concentrating trends with exerted hip contact loads shifting from static walking to dynamic climbing. Similarly, these indicators also exhibited the same trends when the eight models were solved in sequence. Moreover, the relative instability ratio of the medial wall (100%), particularly the anteromedial part (78.7%), was higher than the figure for the lateral wall (36.6%). Conclusion: The anteromedial wall played relatively pivotal stabilizing roles in trochanteric hip fractures compared with the posteromedial wall and the lateral wall, which indicated that orthopedic surgeons should attach more importance to the anteromedial cortex support in an operating theatre.

Finite-Element Analysis of a Novel Cephalomedullary Nail for Restricted Sliding to Reduce Risk of Implant Failure in Unstable Intertrochanteric Fractures

Objective

How to restrict sliding of cephalomedullary nail and rigid reconstruct medial support for unstable intertrochanteric fractures remains a challenge. This study aims to explore the feasibility of a novel cephalomedullary nail for restriction sliding and reconstruction of medial femoral support to prevent failure in unstable trochanteric fractures through finite element analysis.

Methods

The DICOM files of a unilateral femur spiral computed tomography (CT) scans from a elderly female were converted into STL files, and the most common clinical trochanteric fracture model with the absence of medial support, AO/OTA 31‐A2.3 was simulated by removing the posterior medial femur. The model of a novel medial sustain nail (MSN‐II) and a widely used nail (proximal femoral nail anti‐rotation PFNA‐II) were modeled according to the manufacturer‐provided engineering drawing. Different loads were applied to the femoral head to simulate the postoperative weight bearing gait. The sliding distance of helical blade in femoral neck, maximum stress of femur and nail, displacement of proximal fragment were analyzed to revealing the mechanical stability of unstable trochanteric fracture stabilized by different implant.

Results

The sliding distance of helical blade in the femoral neck, the maximum stress on the femur and nail, the displacement of proximal fragment in MSN‐II under 2100N axial load were 0.65 mm, 689 MPa, 1271 MPa, 16.84 mm respectively, while that were 1.43 mm, 720.8 MPa, 1444 MPa, 18.18 mm, respectively in PFNA‐II. The difference between the two groups was statistically significant (P < 0.05) and the stress was mainly distributed in medial distal side of nail but helical blade and the proximal aperture for the nail in MSN‐II. Compared to PFNA‐II, MSN‐II demonstrates biomechanical merit against femur medialization, cut‐out and coax varus.

Conclusion

The sliding distance of helical blade in femoral neck, the maximum stress on the femur and nail, and the displacement of proximal fragment of MSN‐II were less than those of PFNA‐II in the treatment of unstable intertrochanteric fractures. Therefore MSN‐II has better stability than PFNA‐II and it may have the potential to avoid femur medialization and cut out. It might be an option in unstable trochanteric fracture because of its superiority in restricted sliding and medial support reconstruction.

In response to letter to the editor: calcar fracture gapping: a reliable predictor of anteromedial cortical support failure after cephalomedullary nailing for pertrochanteric femur fractures

We appreciate the interest by Drs. Hagiyama and coauthors in our work entitled "Calcar fracture gapping: a reliable predictor of anteromedial cortical support failure after cephalomedullary nailing for pertrochanteric femur fractures". They discussed several pertinent points and it is our pleasure to respond their concerns in order. Firstly, we agree that calcar fracture gap and anteromedial cortical support are different concepts, though both of them were used to evaluate the displacement of fracture reduction quality. Secondly, our primary outcome parameter was the threshold distance of calcar fracture gapping in anteroposterior and lateral fluoroscopies, which was calculated based on sensitivity and specificity by receiver operating characteristic curves. Thirdly, we took immediate post-operative fluoroscopic images in 3 views to describe the initial reduction quality as baseline to compare and calculate the changes with three-dimensional computed tomography, which was taken about one week after operation for confirming secondary stability after head-neck sliding and impaction. Lastly, the parameters selected in multivariable analysis. Future work with better study-design is needed to improve the prediction of patient outcomes.

The application of the 150° oblique tangential fluoroscopic view to detect the posterosuperior femoral neck screw in-out-in intraoperatively

This study investigates the application of the 150° tangential fluoroscopic projection as a novel fluoroscopic view to detect the posterosuperior screw in–out–in (IOI) in the cannulated screws fixation of femoral neck fractures. A retrospective analysis was conducted including 33 patients with femoral neck fractures enrolled from April to November 2021. All patients underwent closed reduction and internal fixation with cannulated screws under intra-operative C-arm fluoroscopy. The posterosuperior femoral neck screw position (whether in–out–in and the distance to the femoral neck cortex) was evaluated from the standard anteroposterior (AP), lateral view, and tangential view images. Postoperative computed tomography (CT) scan results are considered the gold standard for detecting the femoral neck screw locations. Of 33 patients, no femoral neck screws were found to be placed IOI under the standard AP and lateral views. The tangential view revealed the posterosuperior screw was IOI in 8 patients, whereas the average distance between the posterosuperior screw and the posterior femoral neck cortex was 2.73 ± 1.06 mm under the standard lateral view. Postoperative CT verified that posterosuperior screw was placed IOI in these 8 patients. In the other 25 patients with the tangential view showed the posterosuperior screw completely contained in the femoral neck, the average distance between the posterosuperior screw and the posterior femoral neck cortex was 5.48 ± 1.26 mm under the standard lateral view and 2.76 ± 1.08 mm under the tangential view, with a statistically significant difference between the two groups (p < 0.05). Post-operative CT demonstrated that the femoral neck screws were completely contained in the femoral neck in these 25 patients. Intra-operative tangential view of 150° can effectively identify the posterosuperior screw IOI in the cannulated screws fixation of femoral neck fractures. Based on our study, we highly recommend the tangential view as a routine intraoperative fluoroscopic angle to detect the posterosuperior screw IOI.

The Effect of Humanized Nursing Intervention Guided by Computed Tomography Images on Elderly Patients Undergoing Anesthesia for Femur Intertrochanteric Fractures under Intelligent Reconstruction Algorithm

This research was aimed at analyzing the effect of humanized nursing intervention combined with computed tomography (CT) imaging in the surgical anesthesia of femur intertrochanteric fractures (FIF) in the elderly. An image reconstruction algorithm was proposed based on nonlocal mean (NLM) algorithm, which was named as ONLM, and its performance was analyzed. A total of 114 elderly patients with FIF were equally and randomly divided into a humanized nursing group (57 cases) and a routine nursing group (57 cases). They were performed with CT imaging scan based on the ONLM algorithm, and the clinical indicators of the two groups of patients were recorded. The root mean square error (RMSE) and mean absolute error (MAE) of the CT images constructed using the ONLM algorithm were significantly lower than those using NLM algorithm, edge filtering algorithm, and total variation model, while the peak signal-to-noise ratio (PSNR) was the opposite (P < 0.05). The operation time, hospitalization days, intraoperative blood loss, postoperative drainage, and anesthesia preparation time of patients in the humanized nursing group were significantly lower than those in the routine nursing group. The number of patients with excellent Harris scores in the humanized nursing group was higher than that in the routine nursing group, and the number of patients with poor Harris scores was lower (P < 0.05). The language pain score, facial pain score, and visual analog simulation (VAS) scores of patients in the humanized nursing group were significantly lower than those in the routine nursing group. The numbers of postoperative hip varus and fracture nonunion cases in the humanized nursing group were significantly more than those in the routine nursing group. In short, CT images constructed by the ONLM showed higher performance than those by the traditional algorithm. In addition, CT images constructed by ONLM combined with humanized nursing intervention could more effectively improve the cooperation of patients with surgical anesthesia, reduce surgical pain and fear of patients, improve the prognosis of patients, and lower the occurrence of adverse events.

Calcar fracture gapping: a reliable predictor of anteromedial cortical support failure after cephalomedullary nailing for pertrochanteric femur fractures

Background

Maintaining anteromedial cortical support is essential for controlling sliding and decreasing postoperative implant-related complications. However, adequate fracture reduction with cortical support in immediate postoperative fluoroscopy is not invariable in postoperative follow-ups. This study was conducted to investigate the risk factors leading to anteromedial cortical support failure in follow up for pertrochanteric femur fractures treated with cephalomedullary nails.

Methods

This retrospective study enrolled 159 patients with pertrochanteric fractures (AO/OTA- 31A1 and 31A2) that fixed with cephalomedullary nails. All patients were evaluated as adequate fracture reduction in immediate postoperative fluoroscopy before leaving the operation theater. The patients were separated into two groups based on the condition of the anteromedial cortex in the postoperative 3D CT with full-range observation: those with calcar support maintained in Group 1 and those with calcar support lost in Group 2. Demographic information, fracture classification, TAD (tip-apex distance), Cal-TAD, Parker ratio, NSA (neck-shaft angle), reduction quality score, and calcar fracture gapping were collected and compared. Logistic regression analysis was conducted to explore the risk factors leading to anteromedial cortex change.

Results

Anteromedial cortical support failure was noted in 46 cases (29%). There was no significant difference between the two groups concerning age, sex, side injury, TAD, Cal-TAD, Parker ratio, or NSA. There was a significant difference in the AO/OTA fracture classification in univariate analysis but no difference in the multivariable analysis. The reduction quality score, calcar fracture gapping in the AP (anteroposterior), and lateral views were significantly associated with anteromedial cortical support failure in follow-up after cephalomedullary nailing in the multivariable analysis. The threshold value of calcar fracture gapping for the risk of loss was 4.2 mm in the AP and 3.8 mm in the lateral fluoroscopies. Mechanical complications (lateral sliding and varus) were frequently observed in the negative anteromedial cortical support group.

Conclusions

Good reduction quality was a protective factor, and larger calcar fracture gapping in the AP and lateral views were risk factors leading to the postoperative loss of anteromedial cortical support. Therefore, we should pay close attention to fracture reduction and minimize the calcar fracture gap during surgery.

Low filling ratio of the distal nail segment to the medullary canal is a risk factor for loss of anteromedial cortical support: a case control study

Background

Anteromedial cortical support apposition (positive and/or neutral cortical relations) is crucial for surgical stability reconstruction in the treatment of trochanteric femur fractures. However, the loss of fracture reduction is frequent in follow-ups after cephalomedullary nail fixation. This paper aimed to investigate the possible predictive risk factors for postoperative loss of anteromedial cortex buttress after nail fixation.

Methods

A retrospective analysis of 122 patients with AO/OTA 31A1 and A2 trochanteric femur fractures treated with cephalomedullary nails between January 2017 and December 2019 was performed. The patients were classified into two groups according to the postoperative status of the anteromedial cortical apposition in 3D CT images: Group 1 with contact “yes” (positive or anatomic) and Group 2 with contact “No” (negative, loss of contact). The fracture reduction quality score, tip-apex distance (TAD), calcar-referenced TAD (Cal-TAD), Parker ratio, neck-shaft angle (NSA), and the filling ratio of the distal nail segment to medullary canal diameter in anteroposterior (AP) and lateral fluoroscopies (taken immediately after the operation) were examined in univariate and multivariate analyses. Mechanical complications were measured and compared in follow-up radiographs.

Results

According to the postoperative 3D CT, 84 individuals (69%) were categorized into Group 1, and 38 individuals (31%) were classified as Group 2. The multivariate logistic regression analysis showed that the poor fracture reduction quality score (P < 0.001) and decreasing filling ratio in the lateral view (P < 0.001) were significant risk factors for the loss of anteromedial cortical contact. The threshold value for the distal nail filling ratio in lateral fluoroscopy predicting fracture reduction re-displacement was found to be 53%, with 89.3% sensitivity and 78.9% specificity. The mechanical complication (varus and over lateral sliding) rate was higher in Group 2.

Conclusions

The fracture reduction quality score and the decreasing filling ratio of the distal nail to the medullary canal in the lateral view (a novel parameter causing pendulum-like movement of the nail) were possible risk factors for postoperative loss of anteromedial cortical support.

Reduction of trochanteric fractures in lateral view is significant predictor for radiological and functional result after six months

OBJECTIVES

The goal of our retrospective study was to determine which radiological parameter after fixation of trochanteric fractures type AO 31 A2 is most important for the position of the fracture after six months. The additional goal was to find how the end position influences mechanical failure and the mobility of the patients.

PATIENTS AND METHODS

We analysed 92 patients operated in one-year period for A 2 type trochanteric fractures with sliding hip screw or proximal femur intramedullary nail. They were divided in two groups according to the radiological position of the proximal fragment six months after the surgery. In group A we had 46 patients with satisfactory and in group B 46 patients with unsatisfactory position. In anteroposterior view we evaluated neck-shaft angle (NSA) and medial cortical support (MCS) and in lateral view anterior cortical support (ACS). Unsatisfactory position was recognized if NSA was in varus or ACS or MCS were negative. We compared the groups regarding basic patients characteristics (age, gender, ASA score, preinjury mobility, and degree of osteoporosis), type and quality of fixation, the position of the fracture (postoperatively and after 6 months), mechanical failure and mobility after 6 months. Statistical significance level was set to p ≤ 0.05.

RESULTS

Basic patients' characteristics as well as type and quality of fixation did not significantly differ between the groups. After the injury the difference between the groups in reduction quality was significant in lateral view (ACS; p=0.001), while after half a year there were significant differences in both views: NSA (p=0.003), ACS and MCS (both p<0.001). Proximal fragment position after six months statistically significant correlated with postoperative ACS in B group (r = 0.386, p = 0.008), but not with NCA nor with MCS. There were also significantly more fixation failures in group B (p<0.001) and less patients regain preinjury mobility (p=0.029).

CONCLUSIONS

In trochanteric fractures reduction in lateral view is the most important prognostic factor for favourable radiological result after half a year. Unsatisfactory position of the proximal fragment after six months influences mechanical failures and walking ability.