Wiring technique for lesser trochanter fixation in proximal IM nailing of unstable intertrochanteric fractures: A modified candy-package wiring technique

Application of lesser trochanteric reduction fixator in the treatment of unstable intertrochanteric fractures

BACKGROUND

Closed reduction and internal fixation with intramedullary nails has been widely accepted for treating intertrochanteric fractures.

AIM

To focus on how to avoid displacement of the lesser trochanter in unstable intertrochanteric fractures.

METHODS

We developed a lesser trochanteric reduction fixator for treating intertrochanteric fractures through fixing the lesser trochanter by combining the loop plate through the fixator after reduction by the reducer. Five patients with intertrochanteric fractures treated with the newly developed lesser trochanteric reduction fixator and loop plate combined with intramedullary nails, and 20 patients with intertrochanteric fractures treated with simple intramedullary nails were selected from December 2020 to March 2021.

RESULTS

The postoperative Harris hip score was significantly higher in patients treated with the lesser trochanteric reduction fixator than in patients treated without the lesser trochanteric reduction fixator, which indicated that this lesser trochanteric reduction fixator had a positive impact on rehabilitation of the hip joint after surgery and could significantly improve the quality of life of patients.

CONCLUSION

We fully realize the significance of trochanteric reduction and fixation, namely, reconstruction of structures under pressure, in the treatment of intertrochanteric fractures. As long as the general condition of patients is favorable and they are willing to undergo surgery, fixation of the main fracture end should be performed and the lesser trochanter should be reduced and fixed at the same time.

Biomechanical comparison of screw vs. cerclage refixation in orthogeriatric lesser trochanteric fractures: a cadaveric study

PURPOSE

Osteoporosis-related proximal femur fractures continue to increase significantly due to demographic change. This study was designed to evaluate the biomechanical stability of two different fixation methods (cerclage vs. screw) for refixation of a trochanter minor fragment in the pertrochanteric fractures in cadaveric bones.

METHODS

Artificial bones (n = 14) and human bones (n = 16) were treated with a DHS and the trochanter minor fragment was reduced by cerclage wiring or direct screw fixation. After preloading the simulated iliopsoas with 10 N, a tensile test was performed, ending with either a 70% loss of strength or avulsion of the fragment. The mean values of the avulsion force and the surface strain were recorded.

RESULTS

All tensile tests showed no significant differences between refixation using a direct screw or wire cerclage, for both artificial bones and human specimens. Absolute values showed higher avulsion forces after direct screw fixation than refixation with a wire cerclage. The surface tension of specimens treated with direct screw fixation was lower than that of specimens treated with wire cerclage. An opposite effect was seen in artificial bones. Both effects were not statistically significant.

CONCLUSION

Based on the equal stability after lag screw placement compared to cerclage wiring, we promote the placement of a lag screw into the lesser trochanter fragment in pertrochanteric femur fractures when using a dynamic hip screw.

LEVEL OF EVIDENCE

Level III.

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.

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.

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.

When to Reduce and Fix Displaced Lesser Trochanter in Treatment of Trochanteric Fracture: A Systematic Review

Purpose

To systematically evaluate the benefits of reducing and fixing displaced lesser trochanter (LT) of trochanteric fractures and when this procedure is worth the effect.

Methods

From database establishment through March 2021, four online databases (PubMed, Cochrane, Embase, and Web of Science) were searched for relevant literature that investigated reduction and fixation for displaced LT of trochanteric fractures. The papers were then screened by two reviewers independently and in duplicate according to prior inclusion and exclusion criteria. Demographic data as well as data on fracture types, surgical protocols, and surgical outcomes were recorded, analyzed, and interpreted.

Results

Total 10 clinical studies with 928 patients were included, in which 48 cases had intact LT and 880 cases involved the displaced LT, of which 196 (22.27%) cases underwent reduction and fixation for LT while the rest of 684 (77.73%) cases not. In these studies, complications were evaluated as a more applicable predictive parameter for operation than postoperative hip function.

Conclusion

It was beneficial to reduce and fix the displaced LT when one of the conditions below occurred: displacement distance of LT ≥2 cm, quantity of comminuted LT fragments ≥2, and range of LT fragments in medial wall ≥75%; the fracture line of LT fragments reaching or exceeding the midline of the posterior wall.

Banding with lesser trochanter fragment using nonabsorbable tape in trochanteric femoral fractures

Introduction: Trochanteric femoral fracture is one of the most common fractures in the elderly. Trochanteric femoral fracture with involvement of the lesser trochanter is considered unstable and recognized as having a poor prognosis. However, fixation of lesser trochanter fragment is scarce because of technical difficulties. In this study, we reported the simple surgical procedure and the effect of using nonabsorbable tape in lesser trochanter fixation. Methods: From January 2014 to December 2017, 114 patients treated with proximal intramedullary nailing for trochanteric fractures with the lesser trochanter fragment were reviewed. Among patients enrolled in this study, 73 were followed up until radiographic bone union, of which 26 were treated with lesser trochanter fragment banding (group B) and 47 without banding (group N). Radiographs and/or computed tomography images were used to evaluate bone union of the lesser trochanter fragment at three months postoperatively. Results: The bone union of the lesser trochanter fragment was achieved in 24 cases (92%) in group B and 30 cases (64%) in group N. Compared with group N, group B showed a significantly increased number of mild and moderate deformities but decreased number of severe deformity and nonunion (P < 0.001). Postoperative complications were not observed in both groups. Conclusions: From the viewpoint of increasing lesser trochanteric bone union ratio, fixation of the lesser trochanter fragment using nonabsorbable tape in the treatment of trochanteric fractures could be an effective procedure.

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

Background

Anteromedial cortex-to-cortex reduction is a key parameter for stable reconstruction of the fracture fragments during the intertrochanteric fracture fixation. This paper introduces the oblique fluoroscopic projection as a novel method to evaluate the quality of anteromedial cortical apposition.

Methods

Three proximal femur specimens were marked with steel wires along five anatomic landmarks: Greater trochanter, Lesser trochanter, Intertrochanteric line, Anterolateral tubercle and the Anteromedial cortical line. After obtaining the standard femoral neck AP and lateral fluoroscopic images, the C-arm was rotated by every 5°increments until a clear tangential view of the antero-medial-inferior corner cortex was observed. 98 cases of intertrochanteric hip fractures were enrolled from April 2018 to October 2019. After fixation with the nails, the intra-operative anteromedial cortex reduction quality was evaluated from the AP, the true lateral, and the new anteromedial oblique fluoroscopic images. The fluoroscopic results were compared with the post-operative 3D-CT reconstruction images.

Results

The specimen study showed that internal rotation of the C-arm to approximately 30 ° can remove all the obscure shadows and clearly display the antero-medial-inferior cortical tangent line. Clinically,the positive, neutral and negative apposition of different cortices via intra-operative fluoroscopic images showed79, 19 and 0 cases of medial cortical apposition in AP views; 2, 68 and 28 cases of anterior cortices in lateral views;and 22, 51 and 25cases of anteromedial cortical apposition in oblique views respectively. The post-operative 3D-CT reconstruction images revealed that the final anteromedial cortical contact was noted in 62 cases (63.3%), and lost in 36 cases (36.7%). The overall coincidence rate between intra-operative fluoroscopy and post-operative 3D-CT was 63.3% (62/98) in AP view,79.6% (78/98) in lateral view, and 86.7% (85/98) in oblique view(p < 0.001). Negative cortical apposition in oblique view was highly predictive of a final loss of cortical support on 3D CT (24/25 cases, 96%).And non-negative cortical apposition in oblique view was highly associated with true cortical support on 3D CT images (61/73 cases, 83.6%) (p < 0.001).

Conclusions

Besides the AP and lateral projections, an anteromedial oblique view of 30° certifies to be a very useful means for evaluation of the fracture reduction quality of anteromedial cortical apposition.

Intra- and inter-rater reliability of a three-dimensional classification system for intertrochanteric fracture using computed tomography

INTRODUCTION

Intertrochanteric fractures are common fragility fractures in elderly patients. The importance of a reliable classification system for these fractures has been increasingly recognized. The aim of this study was to test the hypothesis that three-dimensional classification by CT has better intra- and inter-observer reliability than conventional two-dimensional classification.

MATERIAL AND METHODS

Two hundred and three consecutive patients (39 male, 164 female; mean age 84.5 years) with intertrochanteric fracture were included in the study. In each case, the fracture was classified using the two-dimensional Evans-Jensen and AO/OTA systems that rely on plain radiographs and using a three-dimensional fragment-based CT system. The second evaluation was performed 1 month after the first evaluation by the same examiner to determine intra-observer reliability. Another blinded examiner also classified each case to assess inter-observer reliability. The kappa coefficient was used for determination of intra- and inter-observer reliability.

RESULTS

The kappa values for the two-dimensional Evans-Jensen and AO/OTA classification systems showed moderate intra-observer reliability (κ=0.65 and κ=0.61, respectively) and slight inter-observer reliability (κ=0.20 and κ=0.19). The intra-observer kappa value for the three-dimensional classification system was 0.88, indicating almost perfect reliability; the inter-observer kappa value was 0.70, indicating substantial reliability.

CONCLUSION

The findings of this study confirm that the fragment-based classification system has high reliability. Surgeons should be aware that the three-dimensional fragment-based CT system for classification of intertrochanteric fractures has better intra-observer and inter-observer reliability than the conventional two-dimensional systems.

The functional effect of lesser trochanter involvement in hip fractures: A prospective cohort study

INTRODUCTION

Hip fractures are the most common fractures amongst frail older patients. Earlier studies have indicated an impaired hip flexion strength in patients with fractures that include detachment of the lesser trochanter. These patients may experience protracted functional impairment and longer recovery time, causing prolonged rehabilitation journeys. This study aimed to evaluate the effects of a detached lesser trochanter in trochanteric fractures on the recovery of hip function.

METHOD

A prospective observational cohort study was performed between 2016 and 2019. Community dwelling patients aged 70 years or older with AO 31A1-A3 trochanteric fractures were included. Patients followed routine care and were treated with a DHS or PFNA. The groups with and without involvement of the lesser trochanter were analysed. The primary outcome was hip function assessed at 6 weeks, 3 months and 1 year after surgery with the Harris Hip Score. Secondary outcomes included the Ludloff's test, complications, rehabilitation time, and pain-, independence-, and quality of life scores. A propensity score was used to adjust for any baseline differences between the two groups.

RESULTS

A total of 114 patients were included, 51 (44.7%) with involvement of the lesser trochanter and 63 (55.3%) without. Minor differences were observed in the baseline characteristics. No significant difference was observed for the Harris Hip Score (coefficient estimate: 3.31; 95% CI, -5.09-11.72; P = 0.43). The flexion function of the iliopsoas muscle was more often normal with the Ludloff's test in patients without involvement of the lesser trochanter (OR, 2.33; 95% CI, 1.241-4.387; P = 0.009). However, no differences were observed for any of the other secondary outcomes.

CONCLUSION

Although no differences in overall hip function were found, more hip fracture patients with involvement of the lesser trochanter showed prolonged impaired flexion of the hip. The absence of long-term, clinically relevant disadvantages however, proves fixing the lesser trochanter to be redundant.

Modified Candy-Package technique vs Cerclage technique for refixation of the lesser trochanteric fragment in pertrochanteric femoral fractures. A biomechanical comparison of 10 specimens

OBJECTIVES

Separation of the lesser trochanteric fragment in pertrochanteric 3-part fractures leads to a significant weakening of the medial cortical wall. Because of the attachment of the Iliopsoas muscle to this structure, the lesser trochanteric fragment tends to cranial dislocation along this muscle's action direction. Refixation of these fractures using an intramedullary nail and an additional wiring osteosynthesis can be considered an operative standard. Based on an intramedullary osteosynthesis procedure, the question was raised whether a 2-point fixation method was favourable over a 1-point method regarding the pull-out resistance of the lesser trochanteric fragment against the Iliopsoas muscle's force.

METHODS

Based on an intramedullary osteosynthesis (PFNA, DePuy/Synthes/SUI), two groups á five human femora were defined depending on the refixation technique of the lesser trochanteric fragment (1-point supertrochanteric "Cable" vs 2-point super/subtrochanteric fixation "Candy-Package" performed with a 1.25-mm steel cerclage). The specimens were tested using a novel traction setup, simulating the activity pattern of the Iliopsoas muscle. The target value was the resistance of the refixated lesser trochanteric fragment against a defined pull-out force produced by the Iliopsoas muscle. The main parameters considered were the peak traction force (Fmax) and the maximum summative work (WFmax) at construct failure.

RESULTS

The Fmax and WFmax displayed a significant difference in favour of the Candy-Package (2-point super/subtrochanteric fixation) group (822 N vs. 476 N, 13.8 k Nmm vs 4.4 k Nmm, respectively; P = 0.01).

CONCLUSIONS

The Candy-Package technique is a method that displays significantly more resistance than a single cerclage osteosynthesis regarding fragment loosening under the application of a simulated Iliopsoas muscle force in the course of a biomechanical proximal femoral 3-part fracture model.

Three-Dimensional Mapping of Medial Wall in Unstable Pertrochanteric Fractures

OBJECTIVE

Unstable pertrochanteric fractures are usually treated with internal fixation, and the integrity of the anteromedial cortex is an important factor for stability and healing. In this study, we described and analyzed the three-dimensional mapping technology and morphological characteristics of pertrochanteric fractures.

METHODS

Fifty-nine pertrochanteric fractures (OTA/AO 2007 types 31A2) were retrospectively reviewed. Computed tomographic (CT) images for all fractures were superimposed on a standard template. Medial wall integrity was analyzed, and three-dimensional fracture maps were created.

RESULTS

Pertrochanteric fractures always have a posterior defect in the medial cortex. The mean width of the defect, in our study, was 21.5 mm (SD: 6.1 mm, range: 10-40 mm), 56.3% (SD: 13.7%, range: 27.5-100%). Bone segments that contact by the anteromedial cortex were 16.5 mm (SD: 5.3 mm, range: 0-29 mm).

CONCLUSION

The integrity of the anteromedial cortex should be considered during internal fixation of femoral trochanteric fractures. These morphological characteristics could be used to form postoperative cortical contact and improve stability of the fixation. Three-dimensional mapping technology can help establish a typical fracture model, thereby improving doctors' understanding of fracture characteristics.

Intertrochanteric Femur Fracture Treatment in Asia: What We Know and What the World Can Learn

Hip fractures are of great interest worldwide as the geriatric population continues to increase rapidly. Currently, surgeons prefer to use cephalomedullary nail for internal fixation of pertrochanteric/intertrochanteric fractures. This article summarizes 10 concepts in hip fracture treatment over the past 20 years, including fracture line mapping, proximal lateral wall and anterior cortex, posteromedial lesser trochanter-calcar fragment, anteromedial cortex support reduction, changes of fracture reduction after sliding and secondary stability, nail entry point and wedge-open deformity, tip-apex distance and calcar-referenced tip-apex distance, femoral anterior bowing and nail modification, long nails for wide medullary canal and large posterior coronal fragment, and postoperative stability score.

Medial wall fragment involving large posterior cortex in pertrochanteric femur fractures: a notable preoperative risk factor for implant failure

INTRODUCTION

To introduce a classification for medial wall fragments in pertrochanteric femur fractures and investigate potential preoperative predictors of implant failure following fixation.

MATERIAL AND METHODS

Medical records of 324 adult patients receiving routine operative treatment using intramedullary devices for pertrochanteric femur fractures with medial wall fragments between August 2008 and May 2018 were retrospectively analyzed. Potential predictors including age, gender, body mass index, comorbidities, AO/OTA classification of fractures were noted. The medial wall fractures were categorized into three types: 1) Type I: avulsion of the lesser trochanter; fracture line does not exceed the base of the lesser trochanter; 2) Type II: fragment involving the posterior cortex near the base of the lesser trochanter; fracture line does not reach the midline of the posterior wall; 3) Type III: fragment involving the large posterior cortex; fracture line reaches or exceeds the midline of the posterior wall.

RESULTS

The 8 (2.5%) implant failures comprised 1 in 186 Type I fractures, 1 in 76 Type II fractures and 6 in 62 Type III fractures. The failure rates of each fracture type were 0.5% in Type I, 1.3% in Type II and significantly increased to 9.7% in Type III (odds ratio [OR], 19.821; 95% confidence interval [CI], 2.337-168.135; p=0.001).

CONCLUSIONS

Type III fractures had a significantly increased failure rate. It is important for orthopedists to identify Type III fractures presurgically, reduction of the medial wall fragment and fixation should be considered during surgery using intramedullary nails.

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

BACKGROUND

The purpose of this study was to analyze cases of AO31-A2 intertrochanteric fractures (ITFs) and to identify the relationship between the loss of the posteromedial support and implant failure.

METHODS

Three hundred ninety-four patients who underwent operative treatment for ITF from January 2003 to December 2017 were enrolled. Focusing on posteromedial support, the A2 ITFs were divided into two groups, namely, those with (Group A, n = 153) or without (Group B, n = 241) posteromedial support post-operatively, and the failure rates were compared. Based on the final outcomes (failed or not), we allocated all of the patients into two groups: failed (Group C, n = 66) and normal (Group D, n = 328). We separately analyzed each dataset to identify the factors that exhibited statistically significant differences between the groups. In addition, a logistic regression was conducted to identify whether the loss of posteromedial support of A2 ITFs was an independent risk factor for fixation failure. The basic factors were age, sex, American Society of Anesthesiologists (ASA) score, side of affected limb, fixation method (intramedullary or extramedullary), time from injury to operation, blood loss, operative time and length of stay.

RESULTS

The failure rate of group B (58, 24.07%) was significantly higher than that of group A (8, 5.23%) (χ = 23.814, P < 0.001). Regarding Groups C and D, the comparisons of the fixation method (P = 0.005), operative time (P = 0.001), blood loss (P = 0.002) and length of stay (P = 0.033) showed that the differences were significant. The logistic regression revealed that the loss of posteromedial support was an independent risk factor for implant failure (OR = 5.986, 95% CI: 2.667-13.432) (P < 0.001).

CONCLUSIONS

For AO31-A2 ITFs, the loss of posteromedial support was an independent risk factor for fixation failure. Therefore, posteromedial wall reconstruction might be necessary for the effective treatment of A2 fractures that lose posteromedial support.

[The measurement and clinical significance of the rotation angles of head-neck fragments after cephalomedullary nail fixation in intertrochanteric fractures]

OBJECTIVE

To measure the rotation angle of the head-neck fragment of intertrochanteric fracture after cephalomedullary nail fixation by three-dimensional CT imaging, and to explore its clinical significance.

METHODS

The clinical data of 68 patients with unstable intertrochanteric fracture of AO/Orthopaedic Trauma Association (AO-OTA) type 31-A2 treated with cephalomedullary nail fixation and with complete intraoperative fluoroscopy and postoperative three-dimensional CT imaging data between July 2016 and October 2018 were retrospectively analyzed. Among them, there were 21 males and 47 females, aged 68-93 years, with an average age of 81.8 years. There were 31 cases of AO/OTA type 31-A2.2 and 37 cases of 31-A2.3. Fracture reduction quality was evaluated according to Baumgaertner et al. and Chang et al. criteria. The anteromedial cortical contact or not of each patient was observed by three-dimensional CT imaging on T3DView software after operation. The rotation of head-neck fragments were divided into three types: non-rotation, flexion rotation, and hyperextension rotation. The rotation angles of each type were measured and the relationship between the rotation type of the head-neck fragments and the contact of the anteromedial cortex was analyzed.

RESULTS

The reduction and fixation of the small trochanter were not performed in 68 patients. According to Baumgaertner et al. criteria, the quality of fracture reduction was excellent in 15 cases (22.1%), acceptable in 50 cases (73.5%), and poor in 3 cases (4.4%). According to Chang et al. criteria, 31 cases were excellent (45.6%), 33 cases were acceptable (48.5%), and 4 cases were poor (5.9%). Thirty-nine cases (57.4%) received anteromedial cortical support and 29 cases (42.6%) did not receive cortical support. Three-dimensional CT imaging showed non-rotation in 12 cases (17.6%), flexion rotation in 39 cases (57.4%), and hyperextension rotation in 17 cases (25.0%). There were 7 cases (58.3%), 30 cases (76.9%), and 2 cases (11.8%) of cortical support in non-rotation group, flexion rotation group, and hyperextension rotation group, respectively. The rotation angles were (1.05±0.61), (13.96±6.17), (8.21±3.88)°, respectively. There were significant differences between groups ( P<0.05).

CONCLUSION

In the unstable intertrochanteric fracture after cephalomedullary nail fixation, the rotation of head-neck fragment exists in most patients, and the types of flexion rotation and non-rotation can easily obtain cortical support reduction.

[Application of wire reduction technique guided by minimally invasive wire introducer in treatment of difficult-reducing intertrochanteric fractures]

OBJECTIVE

To investigate the application effect of wire reduction technique guided by minimally invasive wire introducer in the treatment of difficult-reducing intertrochanteric fractures.

METHODS

Between April 2016 and April 2018, 30 patients with intertrochanteric fractures who had difficulty in closed reduction under the traction bed were treated. There were 17 males and 13 females, aged from 60 to 93 years (mean, 72 years). The causes of injury included falls in 22 cases and traffic accidents in 8 cases. The fractures were classified according to AO/Orthopaedic Trauma Association (AO/OTA) classification: 12 cases of type A1, 12 cases of type A2, and 6 cases of type A3. Intramedullary nail incision and self-made minimally invasive wire introducer were used to assist reduction of intertrochanteric fracture, and then intramedullary nail internal fixation was performed.

RESULTS

The operation time was 30-70 minutes, with an average of 45 minutes. The intraoperative blood loss was 100-210 mL, with an average of 160 mL. One case died of cerebrovascular accident at 3 months after operation; the remaining 29 cases were followed up 6-18 months, with an average of 8.3 months. Postoperative DR reexamination showed that all patients had a good reduction in the fracture end, no retraction, fracture displacement, hip valgus deformity, and other serious complications occurred. The fracture was completely healed and the healing time was 3-8 months, with an average of 6 months. At 3 months after operation, the visual analogue scale (VAS) score was 1-3, with an averge of 1.7. According to Harris functional score of hip joint, 26 cases were excellent and 3 cases were good.

CONCLUSION

For the difficult-reducing intertrochanteric fractures, minimally invasive wire introducer is used to insert steel wire into the incision of head and neck nail for assisted reduction, which can achieve satisfactory reduction results and improve the effectiveness of intertrochanteric fracture.

No difference in flexion power despite iliopsoas fatty degeneration in healed hip fractures with large lesser trochanter displacement

Objective

To evaluate iliopsoas atrophy and loss of function after displaced lesser trochanter fracture of the hip.

Design

Cohort study.

Setting

District hospital.

Patients

Twenty consecutive patients with pertrochanteric fracture and displacement of the lesser trochanter of > 20 mm.

Intervention

Fracture fixation with either an intramedullary nail or a plate.

Outcome measurements

Clinical scores (Harris hip, WOMAC), hip flexion strength measurements, and magnetic resonance imaging findings.

Results

Compared with the contralateral non-operated side, the affected side showed no difference in hip flexion force in the supine upright neutral position and at 30° of flexion (205.4 N vs 221.7 N and 178.9 N vs. 192.1 N at 0° and 30° flexion, respectively). However, the affected side showed a significantly greater degree of fatty infiltration compared with the contralateral side (global fatty degeneration index 1.085 vs 0.784), predominantly within the psoas and iliacus muscles.

Conclusion

Severe displacement of the lesser trochanter (> 20 mm) in pertrochanteric fractures did not reduce hip flexion strength compared with the contralateral side. Displacement of the lesser trochanter in such cases can lead to fatty infiltration of the iliopsoas muscle unit. The amount of displacement of the lesser trochanter did not affect the degree of fatty infiltration.

Level of evidence

II.

Anteromedial cortical support reduction in unstable pertrochanteric fractures: a comparison of intra-operative fluoroscopy and post-operative three dimensional computerised tomography reconstruction

PURPOSE

Anteromedial cortical support reduction is favourable for secondary stability after limited sliding in unstable pertrochanteric fractures. The aim of this study was to compare the accuracy and agreement between intra-operative fluoroscopy and post-operative 3D reconstruction.

MATERIALS AND METHODS

A retrospective analysis of 28 patients (mean 81.6 years) treated with short cephalomedullary nails was performed. All patients had full sets of intra-operative fluoroscopy and post-operative 3D CT images. Observation was focused on the position of the anteromedial cortices of the inferior corner between the head-neck fragment and femoral shaft, and their relationship was categorised into three types: positive, neutral and negative. The percentage of subsequent changes in cortical reduction quality between fluoroscopy and 3D CT was calculated and compared.

RESULTS

There were 24 positive (85.7%), four neutral and no negative positions in the anteroposterior (AP) view and one positive, 20 neutral (71.4%) and seven negative positions in the lateral view from fluoroscopy. On post-operative 3D CT images with a full range of rotation, definitive anteromedial cortical contact (positive and neutral support) was observed in 18 cases (64.3%). Ten cases lost the anteromedial cortical buttress. With the posteromedial region of the lesser trochanter detached, a positive AP cortical position combined with a positive/neutral lateral position on fluoroscopy (17 cases) was highly predictive of reliable, definitive cortical support (15 cases, 88.2%) on 3D CT. A negative lateral position on fluoroscopy (seven cases), regardless of the combination in the AP view, was likely to predict the final loss of cortical support (six cases, 85.7%) on 3D CT; a positive/neutral lateral position (21 cases) was only associated with loss of support in four cases (19.1%) (p < 0.05).

CONCLUSIONS

A lateral negative position of the anterior cortex on fluoroscopy for unstable pertrochanteric fractures may be highly predictive of post-operative final loss of the anteromedial cortical buttress, which should be avoided during operation.