CT scan does not improve the reproducibility of trochanteric fracture classification: a prospective observational study of 53 cases

Preoperative CT improves the assessment of stability in trochanteric hip fractures

Aims

To investigate if preoperative CT improves detection of unstable trochanteric hip fractures.

Methods

A single-centre prospective study was conducted. Patients aged 65 years or older with trochanteric hip fractures admitted to Stavanger University Hospital (Stavanger, Norway) were consecutively included from September 2020 to January 2022. Radiographs and CT images of the fractures were obtained, and surgeons made individual assessments of the fractures based on these. The assessment was conducted according to a systematic protocol including three classification systems (AO/Orthopaedic Trauma Association (OTA), Evans Jensen (EVJ), and Nakano) and questions addressing specific fracture patterns. An expert group provided a gold-standard assessment based on the CT images. Sensitivities and specificities of surgeons' assessments were estimated and compared in regression models with correlations for the same patients. Intra- and inter-rater reliability were presented as Cohen's kappa and Gwet's agreement coefficient (AC1).

Results

We included 120 fractures in 119 patients. Compared to radiographs, CT increased the sensitivity of detecting unstable trochanteric fractures from 63% to 70% (p = 0.028) and from 70% to 76% (p = 0.004) using AO/OTA and EVJ, respectively. Compared to radiographs alone, CT increased the sensitivity of detecting a large posterolateral trochanter major fragment or a comminuted trochanter major fragment from 63% to 76% (p = 0.002) and from 38% to 55% (p < 0.001), respectively. CT improved intra-rater reliability for stability assessment using EVJ (AC1 0.68 to 0.78; p = 0.049) and for detecting a large posterolateral trochanter major fragment (AC1 0.42 to 0.57; p = 0.031).

Conclusion

A preoperative CT of trochanteric fractures increased detection of unstable fractures using the AO/OTA and EVJ classification systems. Compared to radiographs, CT improved intra-rater reliability when assessing fracture stability and detecting large posterolateral trochanter major fragments.

Six-Part Classification of Femoral Intertrochanteric Fractures: A Classification Method to Improve the Diagnosis Rate of Unstable Fractures

OBJECTIVE

Three-dimensional (3D)-CT data is currently insufficient for classifying femoral trochanter fractures. Fracture classification based on fracture stability analysis is helpful to evaluate the prognosis of patients after internal fixation. Currently, there is a lack of fracture classification methods based on 3D-CT images and fracture stability analysis. The aim of this study was to propose a new six-part classification method for intertrochanteric fractures of femur based on 3D-CT images and fracture stability analysis to improve the diagnosis rate of unstable fractures.

METHOD

From January 2009 to December 2019, 320 patients receiving intramedullary nail surgery for femoral intertrochanteric fractures at Chengdu University's Affiliated Hospital were studied retrospectively. AO and six-part classifications were undertaken according to the 3D-CT image data of the patients, and the stability rates of two classifications were compared. According to the six-part classification stability criteria, the patients were divided into a stable and an unstable fracture group. The perioperative and follow-up indicators of the two groups were statistically analyzed, and the six-part classification's inter-observer and internal reliability was examined.

RESULTS

There were 107 men and 213 females women the 320 patients, with an average age of 79.32 ± 11.26 years and an osteoporosis rate of 55.63% (178/320). The fracture stability rate of 39.69% (127/320) was studied using a six-part classification method. The AO classification fracture stability rate was 42.50% (136/320), with no significant difference (χ2  = 0.523, p = 0.470 > 0.05). There is no statistically significant difference between the two classification techniques in the examination of fracture stability (McNemer difference test p = 0.306 > 0.05; Kappa consistency test p < 0.001). According to the six-part classification, fracture stability and instability group were divided into two groups. The following indicators were compared between the two groups: The surgery time (p = 0.280), fracture reduction quality (p = 0.062); function independent measurement (p = 0.075); timed up and go test (TUG) (p = 0.191), and Parker-Palmer score (p = 0.146). Were as compared according to the six-part classification of stable and unstable fracture groups. Perioperative blood loss (p < 0.001), the Harris score excellent and good rate (p = 0.043), fracture healing time (p < 0.001), and the entire weight-bearing duration (p = 0.002) were statistically significant. The difference in femoral head height (FHH) (p = 0.046), the change in femoral neck shaft angle (p = 0.003), the change in medial cephalic nail length (p = 0.033), and the change in tip-apex distance (TAD) (p = 0.002) were statistically significant compared to the relevant markers of imaging stability. Fracture stability had a substantial influence on Harris ratings at 3, 6, and 12 months following surgery, according to repeated measures analysis of variance (F(1,126)  = 32.604, p < 0.001). The effect of time on the Harris score was similarly significant (F(1.893,238.508)  = 202.771, p < 0.001). The observer intra-observer inter-group correlation coefficient (ICC) value was 0.941 > 0.75, the inter-observer ICC value was 0.921 > 0.75, and the intra-observer and inter-observer reliability were both good.

CONCLUSION

The six-part classification of femoral intertrochanteric fractures based on 3D-CT images has broader guiding relevance for femoral intertrochanteric fracture stability analysis. Clinicians will find this classification simpler and more consistent than the AO classification.

The remnant axial cortical length of the proximal femur in pertrochanteric fractures: a three-dimensional computed tomography study and its clinical implications

BACKGROUND

Cortical buttress are important factors for postoperative stable reconstruction of per/inter-trochanteric fractures. The study aimed to measure the remnant axial cortical length (RACL) of the proximal circumference of the femur, and to determine which part of the RACL can be used reliably to postoperatively sustain the head-neck fragment as a cortical support pattern.

METHODS

Eighty patients with trochanteric hip fractures admitted from January 2015 to January 2016 were included in a retrospective study. Their pre-operative computed tomography (CT) images were used to form 3D-CT reconstructions via Mimics software. After simulated rotation and movement for fracture reduction, the RACL, its three component parts-namely, the remnant anterior cortex (RAC), remnant lateral cortex (RLC), and remnant posterior cortex (RPC) -the γ angle between the anterior and posterior cortex, and the Hsu's lateral wall thickness (LWT) were evaluated.

RESULTS

Patients with an A1 fracture (21/80) had a longer RACL (88.8 ± 15.8 mm) than those with an A2 fracture (60.0 ± 11.9 mm; P < 0.01). The RAC, RLC, and RPC of the RACL in A1 fractures were also significantly longer than those in A2 fractures (P < 0.001). However, the most significant difference among the three components of the RACL was in the RPC, which was 27.3 ± 7.8 mm in A1 fractures and 9.2 ± 6.6 mm in A2 fractures. In addition, the coefficient of variation of the RAC was only 20.0%, while that of the RPC was 75.5%. The average γ angle in A1 fractures was 16.2 ± 13.1°, which was significantly smaller than that in A2 fractures, which was 40.3 ± 14.5° (P < 0.001). There was a significant statistical difference in the LWT between A1 and A2 fractures (P < 0.001). There were significant differences in the RACL, RAC, RLC, RPC, γ angle, and LWT among the five subtypes (P < 0.001).

CONCLUSIONS

The RAC is relatively stable in pertrochanteric fractures. Fracture reduction through a RAC buttress may help to enhance the postoperative stable reconstruction of per/inter-trochanteric fractures and make possible good mechanical support for fracture healing.

Analysis of Potential Risk Factors for Cement Leakage into Paraspinal Veins after Vertebroplasty for Acute Osteoporotic Vertebral Fractures Based on a 3D Reconstruction Technique: A Retrospective Matched Case-Control Study

OBJECTIVE

Pulmonary embolism, cardiac embolism, and even cerebral embolism due to paraspinal vein leakage (PVL) are increasingly reported, and their risk factors need to be adequately investigated for prevention. To this end, this study investigated the correlation of the distribution and morphological characteristics of fracture lines with the occurrence of PVL after percutaneous vertebroplasty (PVP), which has not been previously reported.

METHODS

Patients with acute single-segment thoracolumbar osteoporotic vertebral compression fractures (OVCFs) treated with PVP at our institution from January 2019 to July 2022 were selected for a matched case-control study. The case and control groups included those with and without PVL, respectively, matched at a 1:1 ratio based on general clinical characteristics. Additionally, fracture map and heatmap analysis was performed in both groups. In addition to the general clinical characteristics, the vertebral height ratio, puncture angle, delivery rate, and indexes were assessed via the three-dimensional CT reconstruction fracture line mapping technique, namely, the distribution of fracture lines, fracture line length, main fracture line shape, location of fracture line involvement, and number of fracture line branches, were compared between the two groups. The Wilcoxon rank-sum test, t tests, analysis of variance, and conditional logistic regression were used for statistical analysis.

RESULTS

Among 658 patients with OVCFs, 54 who did and 54 who did not develop PVL were included in this study. Significant differences in the puncture angle, fracture line distribution (MR-1, ML-2, MM-2, MR-2, ML-3, MM-3, LL-1, LM-1, LL-2, LM-2), fracture line involvement of the posterior wall, total fracture line length, and main fracture line length were found between the two groups (p < 0.05). Logistic univariate analysis showed significant differences in the puncture angle, fracture line distribution (MR-1, ML-2, MM-2, MR-2, ML-3, MM-3, LL-1, LL-2, LM-2, LL-3), total fracture line length, main fracture line length, and fracture line involvement of the posterior wall between the two groups (p < 0.05). Logistic multifactorial analysis showed that the fracture line distribution (UR-3, ML-3, LM-2, LR-2) and main fracture line length were independent risk factors for the development of PVL in both groups. In addition, the fracture maps and heatmaps showed a greater degree of fracture line encapsulation and more extensive involvement in the middle and lower regions of the vertebral body in the PVL group than in the control group.

CONCLUSIONS

Through a three-dimensional computed tomography reconstruction-based fracture line mapping technique, this study revealed for the first time that the distribution of fracture lines (UR-3, ML-3, LM-2, LR-2) and main fracture line length were independent risk factors for PVL after PVP in patients with acute single-segment thoracolumbar OVCFs. In addition, we hypothesized that the fracture line-vein traffic branch that may appear within 2 weeks after injury in acute OVCF patients may be one of the mechanisms influencing the above potential independent risk factors associated with PVL.

Addition of 3D-CT evaluation to radiographic images and effect on diagnostic reliability of current 2018 AO/OTA classification of femoral trochanteric fractures

INTRODUCTION

The AO/OTA classification for diagnosing femoral trochanteric fractures (31A fractures) was revised in 2018. No studies have investigated whether the addition of CT to radiographic diagnosis improves the inter-rater reliability of classifying 31A fractures with the current AO/OTA criteria. The study aimed to test the hypothesis that the addition of three-dimensional CT (3D-CT) to radiographic diagnosis would improve diagnostic reliability.

METHODS

A retrospective review was conducted to assess the diagnostic reliability of classification of 31A fractures with current AO/OTA criteria. Radiographs and 3D-CT images from 89 cases were assessed. Major fracture types (A1, A2, and A3) and subgroups were diagnosed by nine orthopedic surgeons who were classified into three groups (high-, intermediate-, and low-experience) according to their clinical experience. Anterior-posterior and lateral radiographs were provided to diagnose fracture type (first assessment). After a 6-week interval, radiographs and 3D-CT images of all cases were evaluated by each rater (second assessment). Fleiss's Kappa was used to determine inter-rater reliability.

RESULTS

In the first assessment, the Kappa value indicated fair inter-rater reliability in all groups (high-experience group: κ = 0.296, 95% confidence interval [CI] 0.239-0.352; intermediate-experience group: κ = 0.367, 95% CI 0.305-0.428; low-experience group: κ = 0.304, 95% CI 0.246-0.362). With the addition of 3D-CT (second assessment), reliability improved from fair to moderate in the high- and intermediate-experience groups (κ = 0.483, 95% CI 0.428-0.539 and κ = 0.409, 95% CI 0.352-0.466, respectively). By contrast, reliability remained fair in the low-experience group (κ = 0.322, 95% CI 0.322-0.431). The inter-rater reliability of diagnosing subgroup fracture types improved for A2.3 and A3.1 in all three groups and for A3.2 and A3.3 in the intermediate- and low-experience groups.

CONCLUSION

The current AO/OTA classification revised in 2018 provided fair reliability in diagnosing femoral trochanteric fractures in all three surgeon groups. The addition of 3D-CT to radiographic image evaluation improved reliability in high- and middle-expertise groups. The addition of 3D-CT to radiographic evaluation often improved the diagnostic reliability for unstable fractures, although there was some variation among fracture subgroups.

Assessment of Usefulness of CT Scan in AO Classification of Intertrochanteric Fractures: A Prospective Observational Study

OBJECTIVE

The sliding hip screw (SHS) is the gold standard for the management of stable intertrochanteric (IT) fractures. However, intramedullary implants are now being increasingly used for management of unstable IT fractures especially those with a compromised or vulnerable lateral wall. Therefore, accurate classification of fracture is important to ensure proper surgical planning and choice of implant. The AO classification for IT fractures is based on plain radiographs alone and many authors have reported it to have poor inter- and intra-observer agreement. Therefore, the objectives of the study were to assess the improvement in inter- and intra-observer agreement of the AO classification after addition of CT scan to plain radiographs, to assess the change in pattern of AO classification on addition of CT scan to plain radiographs and to assess percentage of times, stable lateral wall seen on plain radiographs is classified as unstable or broken on CT scans.

METHOD

Fifty-four patients of intertrochanteric fracture were included in study. Plain radiographs of patients were shown to three orthopedic surgeons. They were asked to document the AO classification of the fracture, and comment on the integrity of the lateral wall. Then, CT scans with 3D reconstructions of the same patients were provided along with the radiographs and they were asked to classify the fracture again. Inter- and intra-observer agreement of the AO classification based on plain radiographs alone and once CT scan with 3D reconstruction was added to the plain radiographs was determined using Kappa coefficients. Pattern of change in classification on addition of CT scan to plain radiographs was also assessed.

RESULT

The mean kappa value for inter- and intra-observer agreement for AO classification on plain radiographs alone were 0.58 (moderate) and 0.66 (substantial), respectively. Upon addition of CT scan to plain radiographs, both improved to 0.70 (substantial) and 0.77 (substantial), respectively. The AO classification of the fracture changed 28.70% times (93 of 324 observations) upon addition of CT scan to plain radiographs. 96.77% times (90 of 93 observations) the classification was upgraded to higher group, while it was downgraded in only 3.22% times (3 of 93). 55.91% times this change was observed in AO 31 A 2 group (52 of 93 observations). In 17.59% cases (57 of 324 observations), fractures which were classified as stable (A1.1-A2.1) on radiographs alone, were reclassified as unstable (A2.2-3.3) upon addition of CT scan to plain radiographs. In 11.4% cases (37 of 324 observations), the lateral wall was classified as vulnerable or broken on CT scans where it was classified intact on plain radiographs.

CONCLUSION

Addition of CT scans with 3D reconstructions to plain radiographs improves the intra- and inter-observer agreement of the AO classification. Addition of CT scan results in change in classification of the fracture in about one out of three cases. This most commonly happens in the AO 31 A 2 group. Most of the times, this results in the classification of fracture being upgraded. Many fractures which are initially classified as stable (A1.1-A2.1) on radiographs are reclassified as unstable (A2.2-3.3) on addition of CT scans. The lateral wall is also classified as vulnerable or broken more number of times on CT scans than plain radiographs alone. Therefore, we conclude that CT scan with 3 D reconstructions definitely helps in better pre-operative classification of intertrochanteric fractures especially in select group of fractures (AO 31 A 2) where stability and integrity of lateral wall is difficult to assess.

Effect of propolis extract on clinical parameters and salivary level of matrix metalloproteinase 8 in periodontitis patients: A randomized controlled clinical trial

Background. Periodontitis is the bacterial-induced inflammation of tooth-supporting structures. Local antibacterial agents are used as adjunctive therapy in the treatment of periodontitis. This study aimed to compare the effect of subgingivally delivered propolis extract (a resin produced by honey bees) with chlorhexidine (CHX) mouthwash on clinical parameters and salivary levels of matrix metalloproteinase 8 (MMP-8) in periodontitis patients.Methods. Twenty-eight periodontitis patients in stage II or III and grade B, who had deep periodontal pockets (≥4 mm) around at least three non-adjacent teeth, were divided into two groups. In the control group, patients were prescribed 0.2% CHX mouthwash twice a day for two weeks. In the 20% propolis hydroalcoholic group, subgingival irrigation was performed twice a week for two weeks. Clinical parameters were measured at baseline and after two months. Salivary samples were collected from the propolis and control groups at baseline and two months later to assess MMP-8 levels using the enzyme-linked immunosorbent assay. Additionally, salivary samples from 12 periodontally healthy subjects were used to determine the normal levels of MMP-8. The data were analyzed using SPSS. P<0.05 was considered the level of significance.Results. In the healthy group, the mean salivary levels of MMP-8 were significantly lower than that in the control and propolis groups at baseline (P<0.001). The results indicated a significant improvement in clinical parameters (P<0.001) in the propolis group compared to the control group, while MMP-8 levels decreased significantly in both groups (P<0.001).Conclusion. Propolis is recommended as adjunctive therapy for periodontitis patients. Clinical trials registration code: IRCT2016122030475N3.

Inclinometer: A new device for measuring intermolar torque and angle

The torque of posterior teeth is of great importance in esthetics and occlusion. In the present article, we introduce a simple but useful device to measure intermolar torque. The device consists of two movable and adjustable arms that lie on the selected molar teeth bilaterally; the graduated plane at the body of the appliance then shows the intermolar torque. This device can measure intermolar torque easily and rapidly, with high validity and at a low cost.

Intraoperative use of cortical step sign and diameter difference sign: Accuracy, inter-rater agreement and influence of surgical experience in subtrochanteric transverse fractures

BACKGROUND

The cortical step sign (CSS) and diameter difference sign (DDS) are radiographic tools for torsional alignment control in intramedullary nailing. They have been found to be highly relevant in objective radiographic measurements, but for intraoperative visual identification they lack sufficient evidence yet. The aim of this experimental study was to evaluate their (1) accuracy, (2) inter-rater agreement, (3) predictors of correct identification for clinically relevant maltorsion (CRM: ≥15°), and (4) positive and negative predictive values.

HYPOTHESIS

Sensitivity and specificity of CSS and DDS in visual identification of CRM are comparable to those in objective measurement.

MATERIAL AND METHODS

Six observers of three different levels of surgical experience evaluated 50 a.p. and 50 lateral views of subtrochanteric fractures of cadaveric specimens with internal/external maltorsion from 0° to 30° to assess for CSS, DDS, and CRM. (1) Sensitivity and specificity were evaluated. Percentage agreement and Cohen's Kappa were used to evaluate accuracy as agreement with measured/true values and (2) inter-rater agreement. To determine (3) significant predictors of correct identification of the CSS, DDS, and CRM, a mixed-effects logistic model was constructed, and (4) predictive values were calculated.

RESULTS

(1) Sensitivities of CSS and DDS for CRM (0.99±0.03 and 0.88±0.06) were close to those in objective measurement (1.00 and 0.90). So were specificities (0.25±0.08 and 0.47±0.17 vs. 0.32 and 0.47). Agreement percentage for CSS was high (90-94%, kappa 0.40-0.69), for DDS and CRM it was slightly lower (74-82%, kappa 0.34-0.57 and 62-76%, kappa 0.26-0.49). (2) Inter-rater agreement also showed the highest values for CSS (88-96%, kappa 0.51-0.73) with slightly lower values for DDS (74-84%, kappa 0.36-0.63) and CRM (62-84%, kappa 0.21-0.68). (3) Training level and the magnitude of maltorsion were found the most relevant predictors of a correct identification of CSS/DDS/CRM. (4) DDS showed a higher positive predictive value (73.1%), CSS a higher negative predictive value (93.5%).

DISCUSSION

We found visual identification of CSS and DDS to be almost as accurate as objective measurement in the detection of CRM. Estimation of maltorsion is not sufficiently reliable, but a negative CSS excludes a CRM with high probability. Both signs should be applied by experienced surgeons.

LEVEL OF EVIDENCE

Level III, experimental setting, non-randomised experimental trial.

Three-dimensional mapping of intertrochanteric fracture lines

Supplemental Digital Content is available in the text

Background:

Available research about the anatomic patterns of intertrochanteric fractures is lacking, and fracture mapping has not previously been performed on intertrochanteric fractures. This study aimed to determine the major trajectories of intertrochanteric fracture lines using computed tomography data from a series of surgically treated patients.

Methods:

In this study, 504 patients with intertrochanteric fractures were retrospectively analyzed. Fracture patterns were graded according to Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification. Fracture lines were transcribed onto proximal femoral templates and graphically superimposed to create a compilation of fracture maps that were subsequently divided into anterior, posterior, lateral, and medial fracture maps to create a three-dimensional (3D) pattern by reducing fragments in the 3D models. The fracture maps were then converted into frequency spectra. The major fracture patterns were assessed by focusing on the lateral femoral wall, lesser trochanter, intertrochanteric crest, and inner cortical buttress.

Results:

Anterior, posterior, lateral, and medial fracture maps were created. The majority of fracture lines (85.9%, 433/504) on the anterior maps were along the intertrochanteric line where the iliofemoral ligament was attached. In the medial plane, the majority of fracture lines (49.0%, 247/504) shown on the frequency spectrum included the turning point involving the third quadrant. In the posterior plane, the majority of fracture lines (52.0%, 262/504) involved the intertrochanteric crest from the greater to the lesser trochanter. In the lateral plane, the majority of fracture lines (62.7%, 316/504) involved the greater trochanter at the gluteus medius attachment.

Conclusions:

The fracture patterns observed in the present study might be used to describe morphologic characteristics and aid with management strategies. Further classifications or modifications that incorporate the fracture patterns identified in this study may be used in future research.

Does Computed Tomography Improve Reproducibility in the Classification of Transtrochanteric Fractures?

With the aging of the population, there was a significant increase in the prevalence of hip fractures, with high mortality rates, sequelae and expenses. Understanding the fracture profile and classifying it correctly is critical to define the appropriate treatment. Several radiographic classifications have been developed for transtrochanteric fractures, such as Tronzo, Evans-Jensen, AO and Boyd-Griffin, but their reproducibility is not always satisfactory. The present review aimed to elucidate whether the addition of computed tomography (CT) implies a greater reproducibility than simple radiography in the classification of transtrochanteric fractures, and whether this is a better examination to identify the fracture trait. A search was conducted in the PubMed, Lilacs, Scielo and Cochrane databases between July 2016 and June 2017, limited to the last 15 years. All retrospective, prospective and systematic reviews articles published in the English language, with evaluation of men and/or women, were considered for review. We have excluded case reports, studies that evaluated tomography or radiographs in isolation, and duplicate studies. The research presented 112 articles, of which 5 contemplated the proposed criteria. Reproducibility for the classification of transtrochanteric fractures presented variable results and was influenced by factors such as the type of classification, the use of the simplified or complete classification, the specialty of the evaluator, his experience, and the methodology proposed by the works. There are indications that there is benefit for the use of CT, especially for fractures considered unstable, but its use as a tool to ensure better reproducibility (intra- and interobserver) remains controversial and needs further studies.

Clustering of morphological fracture lines for identifying intertrochanteric fracture classification with Hausdorff distance-based K-means approach

OBJECTIVES

The aim of this study was to develop a systematic three-dimensional (3D) classification of intertrochanteric fractures by clustering the morphological features of fracture lines using the Hausdorff distance-based K-means approach and assess the usefulness of it in the clinical setting.

METHODS

We retrospectively analyzed the data of 504 patients with intertrochanteric fractures who underwent closed reduction and intramedullary internal fixation. The morphological fracture lines of all patients extracted from computed tomography were transcribed freehand onto the template. All fracture lines were then clustered into five distinct types using the Hausdorff distance-based K-means clustering method. Five radiographic parameters and four functional parameters were used to evaluate the postoperative functional states and mobilization levels. Postoperative complications were also recorded.

RESULTS

Intertrochanteric fractures were classified into five types: type I (108/504, 21.4%), simple fracture with intact lateral femoral wall and greater trochanter fragment; type II (85/504, 16.9%), simple fracture with intact lateral femoral wall with/without lesser trochanter detachment; type III (147/504, 29.2%), fractures with intertrochanteric crest detachment involving the lesser trochanter and greater trochanter with an intact lateral femoral wall; type IV (113/504, 22.4%), fractures with large intertrochanteric crest detachment and large lesser trochanter and greater trochanter detachment partially involving the lateral femoral wall and less medial cortical support; type V (51/504, 10.1%), a combination of pertrochanteric and lateral fracture line involving the entire lateral femoral wall and lesser trochanter detachment. Parameters of femoral neck-shaft angle and sliding distance of the cephalic nail were significantly different among types. The complication rate generally increased from type I to type V (P = 0.035).

CONCLUSIONS

The unsupervised clustering can achieve identification of the type of intertrochanteric fractures with clinical significance. The Tang classification can be used to describe fracture morphology, predict the possibility of achieving stable reduction and the risk of complications following intramedullary fixation.

CT-measurement predicts shortening of stable intertrochanteric hip fractures

Purpose

Intertrochanteric (IT) hip fractures can be treated with sliding hip screws (SHS) or cephalomedullary nails (CMN) based on the stability of the fracture. This stability is affected by the initial impaction of the fracture which can be difficult to assess. The aim of this paper is to develop specific pre-operative computed tomography (CT) measurements of IT fractures which are predictive of post-operative shortening.

Methods

A retrospective review was performed of 141 patients with AO/OTA 31A1 or 31A2 fracture patterns, who had pre-operative radiographs and CT scans, and who were treated with a SHS or a CMN. Pre-operative and post-operative imaging of IT fractures were analyzed for those fractures that shortened ≥15 mm post-fixation.

Results

11 fractures shortened ≥15 mm with CMN being protective of shortening (6/36 SHS versus 5/105 CMN, p = 0.0268). A novel measurement made on the pre-operative CT scan called the cortical thin point (CTP) detected differences between patients with <15 mm and ≥15 mm of post-operative shortening for the SHS group (p = 0.0375). CTP was found to be a reliable predictor for post-operative shortening of ≥15 mm when a cutoff threshold of 9 mm was used in the SHS group (p = 0.0161).

Conclusions

Measuring the CTP is predictive of post-operative shortening after fixation of an IT fracture with a SHS. CMN fixation may be protective of shortening. Patients with a CTP of ≤9 mm are at risk for fracture site shortening of more than 15 mm when treated with a SHS.

Three-dimensional CT Improves the Reproducibility of Stability Evaluation for Intertrochanteric Fractures

OBJECTIVES

Femoral intertrochanteric fractures are among the most common fractures in the elderly. There are various classification systems in intertrochanteric fractures. The aim of these classification systems is to help surgeons choose an appropriate treatment. The treatment of femoral intertrochanteric fractures depends on the results of a stability evaluation using imaging studies. However, it is difficult to evaluate the true fracture line using plain X-ray films, especially on the sagittal plane and for intertrochanteric fractures with complex morphologies. The aim of the current study was to determine whether three-dimensional CT (3DCT) improves the reproducibility of stability evaluation for femoral intertrochanteric fractures.

METHODS

This was a single-center observational study of intertrochanteric fractures. We retrospectively collected patients in our hospital with intertrochanteric fractures that underwent plain X-ray (anteroposterior, lateral view) CT scans with axial images (2DCT) and 3DCT for an injured hip between 1 December 2011 and 30 November 2015. The exclusion criteria were pathological fractures (due to metastasis or primary bone tumors) and previous intertrochanteric surgery. During this period, 61 patients were enrolled. Two patients were excluded because lateral view X-rays were not available. A total of 59 patients (27 women, 32 men) with an average age of 77 years (range, 55-96 years) were included in our final analysis. The stability evaluation (i.e. stable or unstable) and implant choices (i.e. dynamic hip screws or Gamma nail) were recorded independently by four observers (two attending physicians and two residents). All images were reviewed and classified using the AO/OTA and Evans modified by Jensen (EVJE) classification systems. The session was repeated after a 3-month wash-out period. The inter-observer agreement was evaluated using the Kappa test.

RESULTS

The inter-observer agreements, measured by the mean weighted kappa values (expressed as X-ray vs 3DCT) were as follows: For stability evaluation, the mean kappa values for attending physicians and residents were 0.68 versus 0.76 and 0.55 versus 0.56. For implant choices, the mean kappa values for attending physicians and residents were 0.68 versus 0.76 and 0.57 versus 0.65. For AO/OTA classification, the values for attending physicians and residents were 0.67 versus 0.65 and 0.70 versus 0.81. For EVJE classification, the values for attending physicians and residents were 0.66 versus 0.63 and 0.56 versus 0.55.

CONCLUSIONS

Three-dimensional CT improved the reproducibility of stability evaluation for femoral intertrochanteric fractures. Preoperative CT scanning may provide a diagnostic benefit for evaluating the stability of intertrochanteric fractures.

Blood loss in trochanteric fractures: multivariate analysis comparing dynamic hip screw and Gamma nail

INTRODUCTION

Anaemia in patients with trochanteric fracture is associated with increased morbidity and mortality and it is an independent risk factor for functional mobility of patients. Several authors have reported the blood loss following operative treatment comparing different fixation systems but few authors have evaluated many associated variables that could influence the perioperative blood loss.

PURPOSE

To evaluate the blood loss in patients that had their trochanteric fracture stabilized with dynamic hip screw (DHS) or Gamma nail. Multivariate analysis of different variables that can influence blood loss was carried out (type of fracture, antiaggregant or anticoagulant therapy, time to surgery). The hypothesis was that there is no difference in terms of blood loss in patients with trochanteric fracture treated with DHS or Gamma nail considering all these variables.

MATERIALS & METHODS

Perioperative blood loss was evaluated in 417 consecutive patients treated for trochanteric fracture with DHS or Gamma nail between January 2010 and March 2013. The perioperative blood loss was calculated using the Lisander formula modified by Foss-Kehlet based on pre- and post-operative haemoglobin values and transfusion rates. Univariate and multivariate analysis were performed integrating the following variables: type of fracture (A1 vs A2), antiaggregant/anticoagulant therapy vs no therapy, time to surgery (<24 vs >24 hours from trauma), type of implant (DHS vs Gamma nail).

RESULTS

A significant blood loss (p <0.05) was observed between A1 and A2 fracture types (1247ml vs 1796.7ml), antiaggregant/anticoagulant therapy and no therapy (1592.7ml vs 1470.2ml), time-to-surgery <24 and >24 hours from trauma (1584.4ml vs 1323.9ml), DHS and Gamma nail (894.7ml vs 1720.6ml). At multivariate analysis, in the A1 fracture groups the DHS showed a significant lower blood loss compared to Gamma nail (p < 0.05).

CONCLUSIONS

According to the perioperative blood loss, DHS should be used in A1 fractures while Gamma nail can be taking in account for the unstable A2 fractures.

Prospective study of the reproducibility of X-rays and CT scans for assessing trochanteric fracture comminution in the elderly: a series of 110 cases

BACKGROUND

Trochanteric fractures are common but difficult to analyse in the elderly on plain X-rays. Fixation failures are related to the severity of the comminution, but comminution and the degree of instability are not easy to determine on standard X-rays. Use of computed tomography (CT) improves assessment of complex fractures, but this finding has not been confirmed versus intraoperative data. The primary objective of this prospective study was to determine the error rate when evaluating comminution on X-rays and CT scans. The secondary objectives were to determine whether CT data on comminution and stability were consistent with intraoperative findings and to define the fracture characteristics.

HYPOTHESIS

Standard X-ray assessment underestimates the complexity of trochanteric fractures and is not very reproducible.

METHODS

Between January and December 2013, all proximal femur fractures in the trochanter area of patients aged 75 years or older (mean age 85) were analysed prospectively with standard X-rays and computed tomography (CT). One hundred and ten patients (88 women and 22 men) with trochanteric fractures were included in the study. Fracture stability was evaluated using the Müller AO classification; the other fracture characteristics were evaluated independently. A senior surgeon evaluated the anonymised X-rays. A radiologist specialised in musculoskeletal imaging interpreted the CT scan images. All patients underwent total hip arthroplasty (110 patients) and 104 fixations of the greater trochanter. The X-ray and CT findings were compared to the intraoperative findings (gold standard) to evaluate their reproducibility.

RESULTS

The reproducibility of the X-ray evaluation was poor for comminution, with a kappa of 0.4, sensitivity of 44 % and a negative predictive value of 29 % but a positive predictive value and specificity of 100 %. The CT evaluation had a kappa of 0.94, sensitivity of 95 % and negative predictive value of 79 %. According to the AO classification, unstable fractures were found in 65 patients based on X-rays, 80 patients based on CT scan and 83 patients based on intraoperative findings. Comminution was mainly identified during surgery; it was medial in 34 % of cases, posterior in 22 % and posteromedial in 21.8 %.

DISCUSSION AND CONCLUSION

In the current study, 75.4 % of fractures were complex and unstable, with medial and/or posterior comminution present in three-quarters of these fractures. X-ray assessment underestimates posterior comminution and the complexity of the fracture line and was not very reproducible. The current results of this study suggest that comminution contributes to instability and that this finding is not taken into account in the AO classification, which is not well suited for this type of fracture and raises the question of how to best evaluate and treat these fractures.

LEVEL OF EVIDENCE

Prospective diagnostic study, Level III.

Does the PFNA™ nail limit impaction in unstable intertrochanteric femoral fracture? A 115 case-control series

INTRODUCTION

Femoral neck shortening after dynamic fixation of extra-capsular fracture may impair functional results, but is rarely assessed. The present study measured impaction in stable and unstable fractures (on the Ender classification) treated by PFNA™ nail. The objectives were: 1) to validate the Ender classification to assess fracture stability; 2) to determine whether neck shortening and head purchase quality varied with stability; and 3) to determine the functional impact of femoral neck shortening.

HYPOTHESIS

The study hypothesis was that the PFNA™ nail stabilizes unstable as well as stable fractures.

MATERIALS AND METHODS

One hundred and fifteen consecutive patients, aged over 70 years, operated on for intertrochanteric fracture using the PFNA™ nail were followed up prospectively for 6 months. Multivariate analysis, including age, gender, assembly quality and body-mass index, was applied to assess the predictive power of the Ender classification with respect to femoral neck shortening. Secondly, patients were grouped according to stable versus unstable fracture (n=70 and 45, respectively), and impaction and femoral head purchase were assessed on a dedicated radiographic protocol. Functional results were assessed on Parker score.

RESULTS

In the unstable fracture group, 3 assembly failures required revision by total hip replacement. Ender grade>2 was significantly predictive of>5mm neck shortening. Neck shortening was greater in unstable fracture: 8.1 ± 8.4mm (range, 4-32 mm), versus 2.5 ± 3.7 mm (range, 3-14 mm) (P=0.0004). Mean blade cut-through was 1.2 ± 2.9 mm (range, 1-12 mm) in unstable fracture, versus 0.3 ± 1.3 mm (range, 1-6mm) (P=0.02). Mean cut-out was 2.3 ± 6 mm (range, 2-21 mm) in unstable fracture, versus 0.5 ± 2.6 mm (range, 1-8mm) (P=0.03). Parker scores diminished comparably in the two groups, without significant difference at follow-up: 3.9 ± 2.6 (range, 0-9) in stable and 3.1 ± 1.9 (range, 0-8) in unstable fracture; reduction in Parker score showed no correlation with femoral neck shortening (r=0.013, P=0.88).

DISCUSSION

The PFNA™ nail provides poorer stabilization of unstable compared to stable fracture. Femoral neck shortening should be taken into account in assessing internal fixation hardware perfomances.

LEVEL OF EVIDENCE

Level III. Prospective case-control study.

Traumax screw plate vs. Gamma nail. Blood loss in pertrochanteric fractures treated by minimally invasive osteosynthesis

PURPOSE

This study is aimed to determine whether the Traumax dynamic hip screw reduces perioperative blood loss and transfusion rate compared to the Gamma nail in the treatment of pertrochanteric fractures.

MATERIALS AND METHODS

A series of 331 patients were followed prospectively in a cohort study between February 2008 and October 2011 after a pertrochanteric fracture. Two types of fixation were used, 163 patients were treated with a Gamma nail and 168 patients with a minimally invasive screw plate Traumax. Perioperative blood loss, evaluated by the Mercuriali formula based on pre- and postoperative haemoglobin and transfusion rates were compared in order to assess risk factors.

RESULTS

Increased perioperative blood loss was significantly linked with patient-related parameters (age, anticoagulant and platelet aggregation inhibitor treatment). Type of osteosynthesis and type of fracture were also risk factors for blood loss and transfusion. The Traumax group had significantly lower blood loss (347 ml vs. 577 ml) and transfusion rate (33.9% vs. 63.8%) than the Gamma group. Involvement of the greater trochanter increased the risk of blood loss only in the Gamma group. Functional results and bone healing were comparable at six months follow-up.

CONCLUSION

Screw plate Traumax significantly reduces perioperative bleeding after pertrochanteric fractures. It avoids fracture gaps that tend to maintain bleeding. Given the morbidity and complications related to acute anaemia and blood transfusion, the surgical management of these elderly patients is aided by this choice of fixation.