Loss of the posteromedial support: a risk factor for implant failure after fixation of AO 31-A2 intertrochanteric fractures

Hip arthroplasty following failure of internal fixation in intertrochanteric femoral fractures: classification decision-making for femoral stem selection and clinical validation

AIMS

Following Failed Internal Fixation of Intertrochanteric Fractures (FIF-ITF), the choice of treatment remains a clinical challenge. This study introduces a novel classification system to guide the selection of femoral prostheses in hip arthroplasty (HA) and validates its clinical efficacy.

METHODS

Retrospectively, we analyzed 108 cases from three university-affiliated hospitals between December 2012 and February 2023 involving patients who underwent hip arthroplasty due to Failed Internal Fixation of Intertrochanteric Fractures (FIF-ITF). Patients were classified into three categories based on fracture healing, proximal femoral support, and the severity of femoral cortical defects, with subtypes identified. Surgical outcomes and complication rates were compared between the Classification-based Decision Group and the Non-classification Decision Group.

RESULTS

The Classification-based Decision Group did not differ significantly from the Non-classification Decision Group in operation time, blood loss, or the use of cemented stems. However, the classification system markedly reduced the risk of periprosthetic fractures intraoperatively from 22.5 to 4.4% and postoperatively from 10 to 1.4%. The Classification-based Decision Group also demonstrated higher postoperative Harris Hip Score (HHS) and Visual Analog Scale (VAS) scores.

CONCLUSION

The proposed classification system serves as an innovative clinical tool for femoral prosthesis selection in hip arthroplasty post-FIF-ITF, effectively reducing complications and enhancing hip function in the Classification-based Decision Group, underscoring its significant clinical utility.

Predictive value of tip-apex distance and calcar-referenced tip-apex distance for cut-out in 398 femoral intertrochanteric fractures treated in a private practice with dynamic intramedullary nailing

Introduction

Cut-out, a biomechanical complication, is one of the most common causes of internal fixation failure of trochanteric hip fractures. The tip-apex distance (TAD) and the calcar-referenced tip-apex distance (CalTAD) have been suggested as the radiographic parameters that most predict the risk of cut-out. The purpose of this study was to check whether these two factors could predict implant cut-out in a series 398 of intertrochanteric hip fractures, treated by dynamic intramedullary nailing with the Trigen Intertan short nail.

Methods

We reviewed 398 consecutive intertrochanteric fractures included in a prospective study and treated in a single private hospital by the same surgeon. The radiographic parameters were obtained from anteroposterior (AP) and axial hip plain radiographs before surgery, immediately postoperatively, and every 3 weeks after surgery until 3 months postoperatively, and every month until the 6-month follow-up. The concept of medial cortex support (MCS) was also analyzed as a criterion for evaluating the quality of fracture reduction.

Results

The overall cut-out rate was 2.3% (9/398). The significant parameters in the univariate analysis were AO fracture type, quality of fracture reduction (p = 0.02), TAD (p < 0.001), CalTAD (p = 0.001), and quality of reduction. No statistically significant relationships were observed between the occurrence of cut-out and sex, age, fracture side, and American Society of Anesthesiologists type. Varus collapse and cut-out were only found in cases of negative MCS (22.2% and 77.8%, respectively). Multivariate analysis showed that only TAD showed an independent significant relationship to cut-out (p < 0.001). In this study, CalTAD has no predictive value in the multivariable analysis.

Conclusions

Our findings differed from those in previous reported studies suggesting that CalTAD is the best predictor of cut-out. According to our data, careful optimal reduction ensuring stable fixation with TAD >25 mm reduced the occurrence of cut-out after dynamic intramedullary nailing of intertrochanteric fractures.

Efficacy of poller screw in addition to lag screw in the treatment of intertrochanteric fractures with proximal femoral nail: a biomechanical evaluation

PURPOSE

The most common type of failure in treating intertrochanteric fractures with proximal femoral nails is cut-out due to varus collapse. We aim to evaluate the effect of the poller screw applied to the proximal fragment and the lag screw on varus collapse and stability in intertrochanteric fractures.

METHODS

An unstable intertrochanteric fracture model without medial support was simulated in 20 synthetic femur models. In the poller screw group, in addition to the lag screw, pole screws were applied to the proximal fragment superior and inferior to the lag screw. In the progressive cyclic loading test, starting from 100 N, the loading was increased by 50 N in each cycle, and the test was continued until the maximum load at which failure occurred as a result of conditioning cycles and progressive cyclic loading tests, stiffness, type of failure, force at failure, lag screw displacement, and varus collapse were recorded.

RESULT

The average stiffness was found to be 124.705 N/mm in the poller screw group and 102.77 N/mm in the control group (P < 0.001). The maximum load to failure was 1897.10 N in the poller screw group and 1475.20 N in the control group (P < 0.001). The average displacement of the lag screw within the femoral head was 0.85 mm in the poller screw group and 3.60 mm in the control group (P < 0.001).

CONCLUSION

As a result, it has been shown that poller screws applied around the lag screw increase fixation stiffness and reduce varus collapse.

The clinical efficacy of Medial Sustain Nail(MSN) and Proximal femoral nail anti-rotation(PFNA) for fixation of medial comminuted trochanteric fractures: a prospective randomized controlled trial

PURPOS

To evaluate the clinical efficacy of the Medial Sustain Nail (MSN) for medial comminuted trochanteric fractures fixation in comparison to Proximal Femoral Nail Antirotation (PFNA) through a clinical study.

METHODS

A non-inferiority randomized controlled trial was conducted at a single centre between July 2019 and July 2020. Fifty patients diagnosed comminuted trochanteric fractures were randomly assigned to either the MSN group (n = 25) or the PFNA group (n = 25). A total of forty-three patients were included in the final study analysis. The primary outcome measure was Short Form 36 health surgery physical component summary (SF-36 PCS) score. Secondary outcomes included the Oxford Hip Scores (OHS), weight bearing, complication relate to implant and so on. This study was not blined to surgeons, but to patients and data analysts.

RESULTS

The MSN demonstrated significantly better functional outcomes as measured by SF-36 PCS and OHS at six months postoperative compared to PFNA (p < 0.05). Union of fractures in the MSN group reached 90.9% at three months after surgery, whereas the PFNA group achieved a union rate of 57.1% (p < 0.05). Furthermore, weight-bearing time of MSN group was earlier than PFNA group (p < 0.05). Additionally, complications related to implant usage were more prevalent in the PFNA group (33.3%) compared to the MSN group (4.5%) (p < 0.05).

CONCLUSION

MSN exhibited superior quality of life outcomes compared to PFNA at six months postoperative. This indicates that MSN effectively reconstructs medial femoral support in patients with comminuted trochanteric fractures, which facilitates early weight-bearing and accelerates the recovery process.

TRIAL REGISTRATION

Trial registration number: NCT01437176, Date of the trial registration:2011-9-1, Date of commencement of the study:2011-9, Date of enrolment/recruitment of the study subjects:2019-7.

Development of early complications after treatment of trochanteric fractures with an intramedullary sliding hip screw in a geriatric population

PURPOSE

Although trochanteric fractures (TF) are a frequent event in the geriatric population, studies reporting on complication rates associated with surgical treatment are sparse. Thus, this study investigated the relevance of fracture-, implant-, and surgery-associated complications in TF. Furthermore, the role of possible risk factors for the before mentioned complications was investigated.

METHODS

A consecutive series of patients with TF treated by intramedullary nailing with a sliding screw device was evaluated. Data were sampled retrospectively from the hospital patient information system and anonymized at the source. Demographic data and information regarding fracture pattern, the treatment performed, hospital stay, and evaluation of operative and follow-up radiographs were analyzed. Intraoperative problems (i.e., technical problems with the implant, intraoperative fracture) and postoperative complications were investigated.

RESULTS

Postoperative surgical complications were noted in 11.7%. The most frequent surgical problem was a difficult fracture reduction (13%) and intraoperative fracture dislocation (3.6%). The most frequent postoperative complication was intra-hospital mortality (3.6%), delayed/non-union (2.7%), and a cut-out of the lag screw in the femoral head (2.3%). Implant failure (1,4%) was significantly associated with morbid obesity while cut-out (2,3%) correlated with a higher tip-apex distance (TAD). A complex fracture type and a suboptimal screw position significantly increased the cut-out rate to 5% (p = 0.018).

CONCLUSION

Complications after TF treatment occur frequently. While patient-associated variables such as morbid obesity cannot be influenced by the surgeon, correct fracture reduction and implant positioning remain to be of highest importance.

Lateral wall thickness is not associated with revision risk of medially stable intertrochanteric fractures fixed with a sliding hip screw

Aims

This study aimed to determine whether lateral femoral wall thickness (LWT) < 20.5 mm was associated with increased revision risk of intertrochanteric fracture (ITF) of the hip following sliding hip screw (SHS) fixation when the medial calcar was intact. Additionally, the study assessed the association between LWT and patient mortality.

Methods

This retrospective study included ITF patients aged 50 years and over treated with SHS fixation between 2019 and 2021 at a major trauma centre. Demographic information, fracture type, delirium status, American Society of Anesthesiologists grade, and length of stay were collected. LWT and tip apex distance were measured. Revision surgery and mortality were recorded at a mean follow-up of 19.5 months (1.6 to 48). Cox regression was performed to evaluate independent risk factors associated with revision surgery and mortality.

Results

The cohort consisted of 890 patients with a mean age of 82 years (SD 10.2). Mean LWT was 27.0 mm (SD 8.6), and there were 213 patients (23.9%) with LWT < 20.5 mm. Overall, 20 patients (2.2%) underwent a revision surgery following SHS fixation. Adjusting for covariates, LWT < 20.5 mm was not independently associated with an increased revision or mortality risk. However, factors that were significantly more prevalent in LWT < 20.5 mm group, which included residence in care home (hazard ratio (HR) 1.84; p < 0.001) or hospital (HR 1.65; p = 0.005), and delirium (HR 1.32; p = 0.026), were independently associated with an increased mortality risk. The only independent factor associated with increased risk of revision was older age (HR 1.07; p = 0.030).

Conclusion

LWT was not associated with risk of revision surgery in patients with an ITF fixed with a SHS when the calcar was intact, after adjusting for the independent effect of age. Although LWT < 20.5 mm was not an independent risk factor for mortality, patients with LWT < 20.5 mm were more likely to be from care home or hospital and have delirium on admission, which were associated with a higher mortality rate.

A Good Tip-Apex Distance Does Not Make Up For a Poor Reduction in Intertrochanteric Hip Fractures Treated with an Cephalomedullary Nail: The Utility of the Neck-Shaft Angle in Preventing Fixation Failure

PURPOSE

Determine if any fracture characteristics or radiographic parameters were predictive of fixation failure [FF] within 1 year following cephalomedullary nailing for intertrochanteric fractures.

METHODS

A consecutive series of intertrochanteric hip fracture patients (AO/OTA 31A) treated with a cephalomedullary nail were reviewed. Pre-fixation (neck-shaft angle [NSA], distance from ischial tuberosities to greater and lesser trochanters, integrity of lesser trochanter, and fracture angulation) and post-fixation (post-fixation NSA, posteromedial cortex continuity, lag screw position, tip to apex distance [TAD], and post-fixation angulation and translation) radiographic parameters were measured by blinded independent reviewers. The FF and non-FF groups were statistically compared. Logistic regression was performed to determine radiographic parameter correlates of FF.

RESULTS

Of 1249 patients, 23 (1.8%) developed FF within 1 year. The FF patients were younger than their non-FF counterparts (77.2 years vs 81.0 years, p=0.048), however there were no other demographic differences. The FF cohort did not differ in frequency of TAD over 25 mm (4.3% vs 9.6%, p=0.624) and had decreased mean TAD (13.6mm vs 16.3mm, p=0.021) relative to the non-FF cohort. The FF cohort had a higher rate of a post-fixation coronal plane NSA more than 10° different from the contralateral side (delta NSA>10°, 34.8% vs 13.7%, p=0.011) with the majority fixed in relative varus. For every 1° increase in varus compared to the contralateral side the odds of FF increased 7% (OR=1.065, 95%CI[1.005-1.130], p=0.034) on univariate analysis. On univariate logistic regression, patients with an absolute post-fixation NSA of 10° or more of varus compared to contralateral were significantly more likely to have a FF (OR=3.139, 95%CI[1.067-8.332], p=0.026).

CONCLUSION

Despite an acceptable TAD, post-fixation NSA in relative varus as compared to the contralateral side was significantly associated with failure in intertrochanteric hip fractures fixed with a cephalomedullary nail.

LEVEL OF EVIDENCE

Prognostic Level III.

Trochanteric and subtrochanteric fractures irreducible by closed reduction: a retrospective study

AIM

To explore the preoperative radiographic features and reduction methods of irreducible trochanteric and subtrochanteric fractures of the femur and to compare the perioperative characteristics and prognoses of irreducible and reducible fractures.

METHODS

The data of 1235 patients with femoral trochanteric fractures surgically treated in our hospital between January 2010 and January 2021 were retrospectively analyzed. According to the inclusion criteria and exclusion criteria, 1163 cases of femoral trochanteric and subtrochanteric fractures were included in this study. Fractures in which good or acceptable reduction could not be reached by closed manipulation were defined as irreducible fractures. The preoperative radiographic features, fracture displacement patterns after closed manipulation and intraoperative reduction methods used to treat irreducible fractures were analyzed, and the perioperative characteristics and prognoses of irreducible fractures and reducible fractures were compared.

RESULTS

There were 224 patients in the irreducible group and 939 patients in the reducible group. According to the radiographic features of fractures, irreducible fractures could be divided into four types: those with interlocking of the fracture, sagging of the femoral shaft, splitting of the lateral wall or medial wall, and comminution of the subtrochanteric area. Various kinds of reduction techniques were needed for different types.

CONCLUSIONS

The incidence of irreducible trochanteric fractures was 15.4%, while the incidence of irreducible subtrochanteric fractures was 84.6%. According to the radiographic features of fractures, they can be divided into four types. It is important to identify irreducible fractures preoperatively and make comprehensive plans to the greatest extent possible to shorten the operation time, reduce intraoperative blood loss, and reduce the incidence of complications.

A novel computed tomography-based three-column MLP classification of intertrochanteric fracture

OBJECTIVES

The aim of the present study was to introduce a novel three-dimensional computed tomography (3DCT)-based three-column classification (named "MLP classification system") of intertrochanteric fractures and evaluate its reproducibility and reliability.

METHODS

From September 2020 to September 2022, a total of 258 consecutive patients (60 male, 198 female;mean age 81.3 years) with intertrochanteric fractures were included in this study. The fracture in each case was assessed using a novel three-dimensional computed tomography-based three-column classification. Two examiners tested the intra and inter-observer reliability of this new classification system using kappa variance.

RESULTS

The intertrochanteric region was divided into the medial column, lateral column, and posterior column. Intertrochanteric fractures were documented as M0/1/2L0/1/2/3P0/1/2/3. All fractures were classifiable into the new classification system. The intra-observer kappa values were 0.91 and 0.89, while the inter-observer kappa value was 0.82, both indicating almost perfect reliability.

CONCLUSION

This novel 3DCT-based MLP classification system for intertrochanteric fractures is comprehensive, and reproducible with good agreement. It is based on proximal femur biomechanic characteristics and traumatic mechanism, contributing to formulating more reasonable treatment protocols involving various late-model internal fixation devices. J. Med. Invest. 70 : 524-529, August, 2023.

Predictors of and predictive nomogram for cut-out of proximal femur nail anti-rotation device in intertrochanteric fractures

PURPOSE

This study determined independent predictors and developed a predictive nomogram for failed correction of intertrochanteric fractures due to cut-out of the proximal femur nail anti-rotation (PFNA) device.

METHODS

Demographic and radiological data of 592 adult patients with intertrochanteric fractures (AO 31A) treated by PFNA were collected retrospectively. Independent predictors of cut-out were obtained through univariate and multivariate analyses, and a predictive nomogram was established. The discrimination, calibration, and clinical utility of the nomogram were based on receiver operating characteristic curve (AUC), concordance index (C-index), calibration curve, and decision curve analysis, respectively.

RESULTS

Overall, 18 (3.04%) cases of cut-out occurred. Independent predictors according to the multivariate analysis were body mass index (BMI), poor-to-acceptable quality of reduction, PFNA blade position, and tip-apex distance (TAD). AUC of the nomogram was 0.849, and C-index was 0.849 (95% CI [0.844-0.854]). Bootstrapping yielded a corrected C-index of 0.849. The calibration and decision curves indicated good agreement and clinical benefit of the nomogram.

CONCLUSION

A reliable predictive nomogram was developed for cut-out of the PFNA in intertrochanteric fractures, based on BMI, quality of reduction, blade position, and TAD.

The lesser trochanter "Sling fixation technique" in proximal intramedullary nailing of unstable intertrochanteric fractures: A polymer-based cerclage wiring

Introduction

Lesser trochanter (LT) fixation to restore the continuity of the posteromedial fragment using a cerclage wire has been reported to provide a more stable reduction in the treatment of unstable femoral neck fractures with LT involvement. However, LT fixation is not commonly performed due to the complications associated with the traditional monofilament cerclage metal wires. In this study, we investigate the clinical and radiological outcomes of a new technique for LT fixation in conjunction with Intramedullary (IM) fixation with nail and screws when compared to isolated IM fixation. The Sling Fixation Technique involves a new wiring technique and the use of a polymer-based cerclage cable characterized by iso-elastic properties that is hypothesized to provide better clinical and radiographic outcomes.

Patients and methods

This prospective observational study included 30 patients who underwent proximal IM nailing from July 2019 to April 2020. Thirty consecutive patients (30) were assigned to 2 different treatment groups. Fifteen (15) patients were treated with the IM Nailing and Sling Fixation Technique and 15 with IM nailing only. Patients were comparable for demographic features, fracture pattern, age, gender and associated medical comorbidities. Clinical outcomes were analyzed in terms of time needed to achieve complete weight bearing, Harris hip score (HHS), Barthel Index (BI) and Radiographic Union Scale for Hip (RUSH). The follow-up period was one year.

Results

Time for fracture healing and to achieve weight-bearing in the "Sling" group were shown to be significantly shorter than in the IM group. The Sling group showed furthermore better HHS, BI and RUSH scores when compared to the IM group at 1, 3, 6, and 12 months from the surgery. No complications such as wiring breakage, cut-outs, breakage or pullout of the fixation screws were observed; one case of heterotrophic ossification was reported.

Conclusion

In cases of unstable intertrochanteric fractures of the proximal femur with lesser trochanter involvement, the Sling fixation technique using an isoelastic polymer-based wire showed superior results in terms of stability and consequently better clinical and radiographic outcomes than IM nailing only.

Reduction with Pre-Drilling Combined with a Finger Reduction Tool in Difficult-to-Reduce Intertrochanteric Fracture

Objective

To investigate the feasibility of pre‐drilling combined with a finger reduction tool for the reduction of difficult‐to‐reduce intertrochanteric fractures.

Methods

Patients diagnosed with complicated intertrochanteric fractures during the period from July 2016 to May 2021 at the Affiliated Hospital of our College were enrolled in this study. All patients underwent reduction by pre‐drilling combined with a finger reduction tool followed by fixing with proximal femoral nail antirotation. The outcome of reduction was evaluated by intraoperative fluoroscopy. The operation time, intraoperative fluoroscopy frequency, and incidence of postoperative complications (including infection in the incision area, coxa vara, nail withdrawal, nail breakage, blade cut‐out, lower limb vein thrombosis, and pulmonary embolism) were recorded to evaluate the speed of the operation, the difficulty of the operation, and the prognosis of the patient, respectively. The Harris hip score at 9 months after surgery was used to evaluate the hip recovery.

Results

A total of 52 patients (17 men and 35 women), 61–88 (77.54 ± 7.40) years of age were included in the study. There were 14 patients with cardiovascular or cerebrovascular disease, ten patients with diabetes, three patients with Parkinson's disease, and three patients with respiratory diseases. The fractures included in the study were classified according to the Orthopedic Trauma Association 31 classification system as type A2.2 (n = 36) or type A2.3 (n = 16). The time from injury to surgery was 1–11 (3.35 ± 1.78) days, and the operation time ranged 31–101 (65.67 ± 14.17) min. The intraoperative blood loss ranged from 40 to 100 (67.69 ± 18.24) mL, and the number of intraoperative fluoroscopy images obtained was 12 to 32 (20.42 ± 5.27). The Harris hip score at 9 months after surgery ranged from 84 to 94 (90.06 ± 2.15). Patients were followed for 9–16 (10.63 ± 1.61) months. One patient died of acute myocardial infarction at 9 months after surgery. One patient suffered from nail withdrawal 5 months post‐operation and thus underwent hemiarthroplasty.

Conclusions

Satisfactory reduction can be achieved using a pre‐drilling femoral trochanter combined with a finger reduction tool for the management of difficult‐to‐reduce complex intertrochanteric fractures. This technique does not increase surgical trauma and also reduces the dose of radiation administered to the patient.

A comprehensive 3D CT based classification of intertrochanteric fracture

Introduction

Despite advancements in surgical techniques complications like implant failure is very common after the fixation of intertrochanteric fractures. Classifying these complex fractures based on plain radiographs underestimates the complexity of these fractures which in turn leads to complications. We propose a comprehensive classification of the intertrochanteric fractures based on 3D Non Contrast Computed Tomography (3D NCCT) scan.

Material and methods

A total of 102 patients (51 males and 51 females) with intertrochanteric fractures were included in this study conducted over a time period of 22 months in a Tertiary care center in North India. NCCT proximal femur of the intertrochanteric fracture patients was done to formulate a new CT classification system and classify all fractures. Intra and inter-observer reliability was tested using kappa variance.

Results

New classification system was proposed which included 3 main and a total of 6 groups. All the fractures were classifiable into the new system. Kappa variance of the study showed a good intra and interobserver reliability (0.95 and 0.90) proving clinical agreement of the classification.

Conclusion

This new 3D-CT based classification has the advantages of being easy, comprehensible with high intra and inter-observer reliability. This 3DCT based classification can prove to be useful to detect occult intertrochanteric fractures undetectable in plain radiographs as well as choosing the optimum treatment plan.

Risk factors for cut-outs in geriatric intertrochanteric fractures with cephalomedullary nailing after obtaining acceptable reduction: a case-control study

BACKGROUND

It is irresponsible if we disregard reduction quality to talk about cut-outs in intertrochanteric fractures (ITF) with internal fixation. The aim of this study is to analyze the risk-factors for cut-outs in geriatric ITF with cephalomedullary nailing after obtaining acceptable reduction.

METHODS

In order to investigate the risk-factors for cut-outs in geriatric ITF after obtaining acceptable reduction, we retrospectively reviewed 367 patients who underwent cephalomedullary nail for ITF in our department between September 2016 and December 2021. Potential variables including demographic data and radiological parameters (namely the fracture type, Singh index, lateral wall fracture, cephalic nail position, Parker's ratio index, tip-apex-distance (TAD), and calcar-referenced TAD (CalTAD)) were collected. Logistic regression analysis was performed to identify the significant risk factors for cut-outs.

RESULTS

One hundred twenty-one patients were suitable for this study. Of the 121 cases, nine cases (7.4%) were observed with cut-out or pending cut-out. We found that Age (adjusted odds ratio (OR) 1.158, 95% confidence interval (CI) 1.016 to 1.318, p = 0.028), lateral wall fracture (adjusted OR 11.07, 95%CI 1.790 to 68.380, p = 0.01), and CalTAD (adjusted OR 1.277, 95%CI 1.005 to 1.622, p = 0.045) were independent risk-factors for cut-outs.

CONCLUSIONS

Age, lateral wall fracture and CalTAD are independent risk-factors for cut-outs in geriatric ITF with cephalomedullary nailing after obtaining acceptable reduction. In order to avoid cut-outs, an optimal CalTAD is necessary even obtaining acceptable reduction, especially in the over-aged patients with lateral wall fracture.

CalTAD is the Key Evaluation Tool for Measurement of Cephalic Fixation Position for Predicting Cut-Out in Geriatric Intertrochanteric Fracture Patients with Internal Fixations after Achieving Acceptable Reduction

Objective

To discover the key evaluation tool of the cephalic fixation position for predicting implant failures in geriatric intertrochanteric fracture (ITF) patients treated with internal fixations after achieving an acceptable reduction.

Methods

We measured the geriatric ITF patients undergoing single-screw cephalomedullary nailing (CMN) fixation surgery after obtaining the acceptable reduction (including anatomical reduction and positive medial cortex support reduction) in our treatment group between September 2016 and March 2020 by using four kinds of cephalic fixation position evaluation tools including Cleveland zone system, Parker’s ratio index, tip–apex distance (TAD), calcar-referenced TAD (CalTAD), and analyzed which were the key evaluation tools for measurement of cephalic fixation position for prediction of implant failures in geriatric ITF patients with internal fixations.

Results

Seventy-four ITF patients treated with single-screw CMN fixation after obtaining the acceptable reduction were enrolled in this study. Of the 74 patients, nine cases were observed with implant failures. There were six cases of cut-out and three of pending cut-out. We found that TAD (odds ratio (OR)=1.149; 95% confidence interval (CI), 1.00–1.32; P=.046) and CalTAD (OR=1.140; 95% CI, 1.00–1.30; P=.037) were risk factors for implant failures by univariate analysis, while only CalTAD (OR=1.200; 95% CI, 1.032–1.395; P=.018) was the independent risk factor for implant failures by multivariate analysis. The Kappa coefficient (κ) of CalTAD was .976 (95% CI, .966–.984) by ICC analysis. The ROC analysis showed that the best cut-off value of CalTAD was 23.76 mm with a sensitivity of 77.8% and specificity of 72.3% (area under the curve, AUC =.775; P = .001).

Conclusions

CalTAD is the key evaluation tool for measurement of cephalic fixation position for predicting implant failures in geriatric ITF patients treated with single-screw CMN after obtaining the acceptable reduction.

The lateral femoral wall thickness on the risk of post-operative lateral wall fracture in intertrochanteric fracture after DHS fixation: A finite element analysis

BACKGROUND

Patients with a lateral femoral wall (LFW) fracture were reported to have high rates of re-operation and complication. Although the LFW thickness was a reliable predictor of post-operative or intra-operative LFW fracture, there was a paucity of literature evaluating the critical stress distributions on the femur and screws of intertrochanteric fractures treated with dynamic hip screw (DHS). This study aimed to investigate the biomechanical performance of intertrochanteric fractures with different LFW thickness treated with DHS device.

METHODS

A three-dimensional model of the proximal femur was established by computed tomography images. The intertrochanteric fracture model with three different LFW thickness (10 mm, 20.5 mm and 30 mm, respectively) was created, which was fixed by DHS. The von Mises stress on the proximal femur, lateral femoral wall, DHS and the total displacement of the device components were evaluated and compared for three different LFW thickness model.

RESULTS

The maximum von Mises stress in the proximal fragment of the 10 and 20.5 mm model increased by 80.56% and 57.97% when compared with the 30 mm model. The peek von Mises stress around the blade entry point of the 10 mm and 20.5 mm model increased by 89.26% and 66.39% when compared with the 30 mm model. The peek von Mises in the DHS located near the junction of the barrel and side plate of each model and the 30 mm model had the smallest von Mises stress compared with the other two models. Furthermore, the maximum displacement in the 30 mm model was much smaller than that in the10mm model and 20 mm model.

CONCLUSIONS

The intertrochanteric fracture with a thinner LFW tended to have a higher risk of LFW fracture stabilized by a DHS device. Thus, the intertrochanteric fractures with a thinner LFW should not be treated by DHS alone and the intramedullary nail or an addition of trochanteric stabilization plate(TSP) was recommended.

Risk factors for implant failure of intertrochanteric fractures with lateral femoral wall fracture after intramedullary nail fixation

INTRODUCTION

Few studies have specifically evaluated the comminution extent of lateral femoral wall (LFW) fracture and risk factors of implant failure in intertrochanteric fractures with LFW fracture. The aim of present study was to evaluate the influence of comminution extent of LFW fracture on implant failure and identify risk factors of implant failure in cases with LFW fracture after intramedullary fixation.

METHODS

This retrospective study included 130 intertrochanteric fracture with LFW fracture treated with intramedullary fixation at a teaching hospital over a 13-year period from January 2006 to December 2018. Demographic information, cortical thickness index, the reduction quality, status of medial support, position of the screw/blade and status of lateral femoral wall were collected and compared. The logistic regression analyzes was performed to evaluate risk factors of implant failure in intertrochanteric fractures with LFW fracture after intramedullary nail fixation.

RESULTS

10 patients (7.69%) suffered from mechanical failure after intramedullary fixation. Univariate analyzes showed that comminuted LFW fracture (OR, 7.625; 95%CI, 1.437~40.446; p = 0.017), poor reduction quality (OR, 49.375; 95%CI, 7.217~337.804; p < 0.001) and loss of medial support (OR, 17.818; 95%CI, 3.537~89.768; p < 0.001) were associated with implant failure. After adjustment for confounding variables, the multivariable logistic regression analyzes showed that poor reduction quality (OR, 11.318; 95%CI, 1.126~113.755; p = 0.039) and loss of medial support (OR, 7.734; 95%CI, 1.062~56.327; p = 0.043) were independent risk factors for implant failure. Whereas, comminuted LFW fracture was not associated with implant failure (p = 0.429).

CONCLUSIONS

The comminution extent of the LFW fracture might influence the stability of intertrochanteric fractures; and intramedullary fixation might be an effective treatment method. Furthermore, poor reduction quality and loss of medial support could increaze the risk of implant failure in intertrochanteric fractures with LFW fractures after intramedullary fixation. Therefore, we should pay great emphasis on fracture reduction quality in future.

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.

Prognostic Factors of 1-Year Postoperative Functional Outcomes of Older Patients with Intertrochanteric Fractures in Thailand: A Retrospective Cohort Study

Restoration of ambulatory status is considered a primary treatment goal for older patients with intertrochanteric fractures. Several surgical-related parameters were reported to be associated with mechanical failure without focusing on the functional outcomes. Our study examines the roles of both clinical and surgical parameters as prognostic factors on 1-year postoperative ambulatory outcomes, reaching a good functional outcome (the New Mobility Score: NMS ≥ 5) and returning to preinjury functional status at one year, of older patients with intertrochanteric fracture. Intertrochanteric fractures patients age ≥65 years who underwent surgical treatment at our institute between January 2017 and February 2020 were included. Of 209 patients included, 149 (71.3%) showed a good functional outcome at one year. The pre-injury ambulatory status (OR 52.72, 95%CI 5.19–535.77, p = 0.001), BMI <23 kg/m² (OR 3.14, 95%CI 1.21–8.13, p = 0.018), Hb ≥10 g/dL (OR 3.26, 95%CI 1.11–9.57, p = 0.031), and NMS at discharge ≥2 (OR 8.50, 95%CI 3.33–21.70, p < 0.001) were identified as independent predictors for reaching a good postoperative functional outcome. Only aged ≤80 (OR 2.34, 95%CI 1.11–4.93, p = 0.025) and NMS at discharge ≥2 (OR 6.27, 95%CI 2.75–14.32, p < 0.001) were significantly associated with an ability to return to preinjury function. To improve postoperative ambulatory status, orthopedic surgeons should focus more on modifying factors, such as maintaining the preoperative hemoglobin ≥10 g/dL and providing adequate postoperative ambulation training to maximize the patients’ capability upon discharge. While surgical parameters were not identified as predictors, they can still be used as guidance to optimize the operation quality.

Medial support nail and proximal femoral nail antirotation in the treatment of reverse obliquity inter-trochanteric fractures (Arbeitsgemeinschaft fur Osteosynthesfrogen/Orthopedic Trauma Association 31-A3.1): a finite-element analysis

BACKGROUND

The reverse obliquity inter-trochanteric fracture is a distinct fracture pattern that is mechanically different from most inter-trochanteric fractures and the optional treatment of it is still controversial. The purpose of this study was to compare differences in the efficacy of a novel nail (medial support nail [MSN-II]) and proximal femoral nail anti-rotation (PFNA-II) in the treatment of reverse obliquity inter-trochanteric fractures (Arbeitsgemeinschaft fur Osteosynthesfrogen/Orthopedic Trauma Association [AO/OTA] 31-A3.1) using finite-element analysis.

METHODS

Modeling software was used to establish a three-dimensional model of MSN-II and PFNA-II and an A3.1 inter-trochanteric fracture model. Abaqus software was used to implement different force loads to compare finite-element biomechanical parameters such as the maximum stress in implant and the displacement of fracture site.

RESULTS

The femoral stress, implant stress and fracture site displacement of MSN-II was less than that of PFNA-II. The results indicated that the maximal femoral stress was 581 MPa for PFNA-II and 443 MPa for the MSN-II. The maximum stress values in the PFNA-II and MSN-II models were 291 and 241 MPa, respectively. The maximal displacements of the fracture site were 1.47 and 1.16 mm in the PFNA-II and MSN-II models, respectively.

CONCLUSION

Compared with PFNA-II for inter-trochanteric fracture (AO/OTA 31-A3.1), MSN-II which was designed with a triangular stability structure can provide better biomechanical stability. The MSN-II may be a feasible option for the treatment of reverse obliquity inter-trochanteric fracture.