Proximal femoral nail antirotation versus dynamic hip screw fixation for treatment of osteoporotic type 31-A1 intertrochanteric femoral fractures in elderly patients

Bone Consolidation: A Practical Guide for the Interventional Radiologist

In recent years, interventional radiologists have been increasingly involved in the management of bone fractures resulting from benign (osteoporosis and trauma), as well as malignant (tumor-related impending or pathologic fractures) conditions. Interventional techniques used to fix fractures include image-guided osteoplasty, screw-mediated osteosynthesis, or combinations of both. In the present narrative review, we highlight the most common clinical scenarios that may benefit from such interventional techniques with specific focus on spine, pelvic ring, and long bones.

Lateral cortical notching facilitates dynamization of proximal femoral nailing - A finite element analysis

INTRODUCTION

Dynamization of proximal femoral nailing by removal of distal interlocking is one of the recommended treatment options for nonunions of femur fractures. However, in certain inter-/subtrochanteric fractures, gliding of the nail along the femoral shaft is blocked by lateral femoral cortical support of the lag screw. For these cases, Biber et al. proposed lateral cortical notching (LCN), in which the supporting lateral bone is removed. This study investigates the biomechanical effect of LCN on gliding of proximal femoral nailing and stress distribution at the bone/implant interface.

MATERIALS AND METHODS

In this finite element analysis a three-dimensional model of an unstable intertrochanteric fracture with proximal femoral nailing without distal interlocking was simulated using the FebioStudio software suite. To simulate LCN, the lag screw hole was lengthened to 15.34 mm at the lateral cortex. Displacement of the nail along the femoral shaft axis and von Mises stress distribution were compared between LCN model and standard implantation model.

RESULTS

Displacement of the nail along the femoral shaft axis was higher in the LCN model than in the standard implantation model (0.48 mm vs. 0.07 mm). Highest von Mises stresses of 176-178 MPa at the implant and of 52-81 MPa at the proximal femur were detected. Maximum von Mises stresses of the implant were comparable at all sides, except for a reduced von Mises stress at the lateral inferior side in the LCN model (80 vs. 102 MPa). At the inferior lateral screw hole and the anterior/posterior lateral screw hole maximum von Mises stress was reduced in the LCN model (2 vs. 49 MPa and 52 vs. 81 MPa), whereas the maximum von Mises stress at the inferior medial screw hole was higher in the LCN model than in the standard implantation model (53 vs. 27 MPa).

CONCLUSIONS

Lateral cortical notching facilitates gliding of a distally dynamized proximal femoral nail along the femoral shaft axis in intertrochanteric fractures. Additionally, the lack of lateral cortical bone support at the lag screw reduces von Mises stress at the bone/implant interface and thus could lower the risk for implant breakage and peri‑implant fractures.

Proximal femoral nail anti-rotation vs dynamic hip screws decrease the incidence of surgical site infections in patients with intertrochanteric fractures: A meta-analysis

In this study, a meta-analysis was conducted to comprehensively analyse the effectiveness of using proximal femoral nail anti-rotation (PFNA) and dynamic hip screws (DHS) to treat intertrochanteric fractures on postoperative surgical site infections (SSI). PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched from their inception until December 2022 to identify studies that compared PFNA and DHS in the treatment of intertrochanteric fractures. Two investigators independently screened the retrieved studies to assess their quality and verify their eligibility for inclusion. Meta-analyses were performed with RevMan 5.4 software. Thirty studies, including 3158 patients, met the inclusion criteria. These studies included 1574 patients treated with PFNA, and 1584 were treated with DHS. The findings of the meta-analysis revealed a significant reduction in the incidence of SSI in patients treated with PFNA compared with those treated with DHS (2.64% vs 6.76%, odds ratio [OR]: 0.40, 95% confidence intervals [CIs]: 0.28-0.57, P < .001), superficial SSI (2.58% vs 5.01%, OR: 0.53, 95% CIs: 0.33-0.85, P = .008) and deep SSI (1.26% vs 3.43%, OR: 0.41, 95% CIs: 0.19-0.92, P = .03). PFNA was more effective than DHS in reducing the incidence of SSI. Even so, significant variations in sample sizes among the included studies meant that the methodology for some studies had qualitative deficiencies. Therefore, additional studies with large sample sizes are needed to validate these results.

COMPARING GAIT AND HIP SCORES IN FEMORAL NECK AND INTERTROCHANTERIC FRACTURES

Objective

Treatment modality is controversial in the unstable IT fractures. Ideal hemiarthroplasty treatment for unstable IT fractures should be comparable to that for FN fractures. Therefore, the aim of this study was to compare patients who underwent cementless hemiarthroplasty for a diagnosis of FN and unstable IT in terms of clinical outcomes, functional scores, and smartphone-based gait analysis data.

Methods

Case matching was applied to 50 patients with FN fracture and 133 patients with IT fracture who underwent hemiarthroplasty treatment, they were compared in terms of, preoperative and postoperative walking status, and Harris hip scores. Smartphone-based gait analysis was applied to 12 patients in the IT group and 14 patients in the FN group who could walk without support.

Results

There was no significant difference between patients with IT and FN fractures regarding Harris hip scores, preoperative, and postoperative walking status. In the gait analysis, gait velocity, cadence, step time, step length, and step time symmetry values were observed to be significantly better in patients in the FN group.

Conclusion

Cementless hemiarthroplasty operations for unstable IT fractures have similar hip scores to FN fractures. However, the walking speed and walking symmetry data were seen to be worse. This result should be considered in the selection of appropriate treatment. Level of evidence III; Retrospective study.

Morbidity and Mortality Analysis in the Treatment of Intertrochanteric Hip Fracture with Two Fixation Systems: Dynamic Hip Screw (DHS) or Trochanteric Fixation Nail Advance (TFNA)

BACKGROUND

The aim of this study was to compare the clinical outcomes, complications, and mortality of patients with intertrochanteric hip fracture treated with dynamic hip screw (DHS) vs. trochanteric fixation nail advance (TFNA).

METHODS

We evaluated 152 patients with intertrochanteric fractures concerning age, sex, comorbidity, Charlson Index, preoperative gait, OTA/AO classification, time from fracture to surgery, blood loss, amount of blood replacement, changes in gait, full weight-bearing at hospital discharge, complications, and mortality. The final indicators encompassed the adverse effects linked to implants, postoperative complications, clinical healing or bone healing duration, and functional score.

RESULTS

The study included a total of 152 patients, out of which 78 (51%) received DHS treatment and 74 (49%) received TFNA treatment. The results of this study show that the TFNA group demonstrated superiority (p < 0.001). However, it should be noted that the TFNA group had a higher frequency of the most unstable fractures (AO 31 A3, p < 0.005). Full weight-bearing at discharge also decreased in patients with more unstable fractures (p = 0.005) and severe dementia (p = 0.027). Mortality was higher in the DHS group; however, a longer time from diagnosis to surgery was also observed in this group (p < 0.005).

CONCLUSIONS

The TFNA group has shown a higher success rate in achieving full weight-bearing at hospital discharge when treating trochanteric hip fractures. This makes it the preferred choice for treating unstable fractures in this region of the hip. Additionally, it is important to note that a longer time to surgery is associated with increased mortality in patients with hip fractures.

Sliding hip screw vs intramedullary nail for AO/OTA31A1-A3: a systematic review and meta-analysis

OBJECTIVE

to conduct a systematic review with consequent meta-analysis evaluating the best treatment for Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) 31A1-A3 trochanteric fractures when comparing the sliding hip screw (SHS) to the intramedullary nail (IMN). The outcomes used for comparison are major complications (in total, as well as nonunion and infection specifically), mortality rates, functional outcomes and patient-reported outcome measures (PROM).

MATERIALS AND METHODS

Search strings for the Cochrane Library, CINAHL, Medline and Embase databases were developed with the help of a scientific librarian. Two authors screened the studies from the search string independently using Covidence.org and data extraction was performed similarly. Quality assessment was performed using the Cochrane Risk of Bias tool for randomised trials (ROB2) for RCT studies, and Cochrane Risk of Bias in Non-Randomised Studies - of Interventions (ROBINS-I) for non-RCT studies. Meta-analyses were performed using Log Risk Ratio as the primary effect estimate.

RESULTS

Of the 2,051 studies screened by the two authors, six RCTs and six non-RCTs were included in this meta-analysis, with a total of 10,402 patients. The results indicated no significant differences in total major complications, nonunion, infection or mortality between SHS and IMN treatments for AO/OTA 31A1, 31A2 and 31A3 trochanteric fractures. Due to a lack of compatible data, we were unable to perform a meta-analysis on function scores and PROM. However, there are trends that favour IMN for 31A1 and 31A2 fractures.

CONCLUSION

No significant difference between SHS and IMN was found in the meta-analysis in any of the examined AO/OTA fracture subtypes in terms of primary and secondary outcomes. When assessing function scores and PROM, we found trends favouring IMN for 31A1 and 31A2 fractures that should be explored further.

Cemented hemiarthroplasty versus proximal femoral nail antirotation in the management of intertrochanteric femoral fractures in the elderly: a case control study

Background

The treatment for intertrochanteric femoral fractures (IFF) among the elderly has been a controversial topic. Hemiarthroplasty (HA) and proximal femoral nail antirotation (PFNA) have their own advantages in the management of IFF. Hence, this study aims to compare and analyze differences in the effectiveness of both procedures on IFF among the elderly.

Methods

Overall, 99 patients (81.09 ± 8.29 years; 68 women) underwent HA or PFNA from January 2016 to May 2020. IFF were classified according to the Arbeitsgemeins für Osteosynthesefragen (AO) classification. The difference in underlying diseases, the American Society of Anesthesiologists (ASA) grade, Singh index, Harris scores, surgical time, intraoperative bleeding, postoperative blood test results, postoperative number of days to partially bearing weight, and survival outcomes were analyzed. Postoperative follow-ups were performed every 3 months.

Results

There was no significant difference in the AO classification, underlying diseases, ASA grade, Singh index, surgical time, and survival outcomes of the HA (45 patients) group and PFNA group (54 patients). The HA group was associated with earlier partial weight-bearing (HA: 4 [2 ~ 4.5] days, PFNA: 10 [8~14] days). It also had a higher total Harris score than the PFNA group at the 6-month follow-up visit (HA: 86.8 [81.90 ~ 90.23], PFNA: 83.48 [75.13 ~ 88.23]). Harris scores decreased more in patients aged ≥90 years in the PFNA group than in the HA group. The postoperative stress recovery rate in the HA group was faster based on postoperative blood test results.

Conclusions

PFNA and HA have good therapeutic effects in the treatment of IFF. The advantages of HA were reflected in short-term weight bearing, faster recovery from stress, and better joint function in the long term. This advantage is more obvious in the patient population aged over 90 years. Therefore, we suggest that surgeons should consider the benefit of HA in the treatment of IFF among the elderly.

Trial registration

Chinese Clinical Trial Registry, ChiCTR2000035814. Registered 17 August 2020, https://www.chictr.org.cn/showproj.aspx?proj=57083

Traditional three-dimensional printing technology versus three-dimensional printing mirror model technology in the treatment of isolated acetabular fractures: a retrospective analysis

OBJECTIVE

This study was performed to compare the clinical outcomes of traditional three-dimensional (3D) printing technology and 3D printing mirror model technology in the treatment of isolated acetabular fractures.

METHODS

Prospectively maintained databases were reviewed to retrospectively compare patients with an isolated acetabular fracture who were treated with traditional 3D printing technology (Group T) or 3D printing mirror model technology (Group M) from 2011 to 2017. In total, 146 advanced-age patients (146 hips) with an isolated acetabular fracture (Group T, n = 72; Group M, n = 74) were assessed for a mean follow-up period of 29 months (range, 24-34 months). The primary endpoint was the postoperative Harris hip score (HHS). The secondary endpoints were the operation time, intraoperative blood loss, fluoroscopy screening time, fracture reduction quality, and incidence of postoperative complications at the final follow-up.

RESULTS

The HHS, operation time, intraoperative blood loss, fluoroscopy screening time, and incidence of postoperative complications were significantly different between the groups, with Group M showing superior clinical outcomes.

CONCLUSION

In patients with an isolated acetabular fracture, 3D printing mirror model technology might lead to more accurate and efficient treatment than traditional 3D printing technology.

Traditional and bionic dynamic hip screw fixation for the treatment of intertrochanteric fracture: a finite element analysis

PURPOSE

The dynamic hip screw (DHS) is widely used for fixing intertrochanteric femur fractures. A porous bionic DHS was developed recently to avoid the stress concentration and risk of post-operative complications associated with titanium alloy DHSs. The purpose of this study was to compare the effects of traditional titanium alloy, bionic titanium alloy, and bionic magnesium alloy DHS fixation for treatment of intertrochanteric fractures using finite element analysis.

METHODS

A three-dimensional model of the proximal femur was established by human computed tomography images. An intertrochanteric fracture was created on the model, which was fixed using traditional and porous bionic DHS, respectively. The von Mises stress, maximum principal stress, and minimum principal stress were calculated to evaluate the effect of bone ingrowth on stress distribution of the proximal femur after fixation.

RESULTS

Stress concentration of the bionic DHS model was lower compared with traditional DHS fixation models. The von Mises stress, maximum principal stress, and minimum principal stress distributions of bionic magnesium alloy DHS models improved, along with simulation of the bone healing process and magnesium alloy degeneration, assumed to biodegrade completely 12 months post-operatively. The distribution of maximum principal stress in the secondary tension zone of the bionic DHS model was close to the intact bone. In the minimum principal stress, the region of minimum stress value less than - 10 MPa was significantly improved compared with traditional DHS models.

CONCLUSION

The bionic magnesium alloy DHS implant can improve the stress distribution of fractured bone close to that of intact bone while reducing the risk of post-operative complications associated with traditional internal fixations.

Finite element analysis of two cephalomedullary nails in treatment of elderly reverse obliquity intertrochanteric fractures: zimmer natural nail and proximal femoral nail antirotation-ΙΙ

Background

More elderly patients are suffering from intertrochanteric fractures. However, the choice of internal fixation is still controversial, especially in the treatment of unstable intertrochanteric fracture; thus, previous implants continue to be improved, and new ones are being developed. The purpose of our study was to compare the biomechanical advantages between the zimmer natural nail (ZNN) and proximal femoral nail antirotation-II (PFNA-II) in the treatment of elderly reverse obliquity intertrochanteric fractures.

Methods

A three-dimensional finite element was applied for reverse obliquity intertrochanteric fracture models (AO31-A3.1) fixed with the ZNN or PFNA-II. The distribution, peak value and position of the von Mises stress and the displacement were the criteria for comparison between the two groups.

Results

The stresses of the internal fixation and femur in the ZNN model were smaller than those in the PFNA-II model, and the peak values of the two groups were 364.8 MPa and 171.8 MPa (ZNN) and 832.3 MPa and 1795.0 MPa (PFNA-II). The maximum amount of displacement of the two groups was similar, and their locations were the same, i.e., in the femoral head vertex (3.768 mm in the ZNN model and 3.713 mm in the PFNA-II model).

Conclusions

The displacement in the two models was similar, but the stresses in the implant and bone were reduced with the ZNN. Therefore, the ZNN implant may provide biomechanical advantages over PFNA-II in reverse obliquity intertrochanteric fractures, as shown through the finite element analysis. These findings from our study may provide a reference for the perioperative selection of internal fixations.

Surgical Treatment of Type 31-A1 Two-part Intertrochanteric Femur Fractures: Is Proximal Femoral Nail Superior to Dynamic Hip Screw Fixation?

Introduction The implant of choice for two-part intertrochanteric femur fracture is still under debate. This study was done to compare the operative parameters and functional outcome of two-part intertrochanteric fractures treated by dynamic hip screw (DHS) and proximal femur nail (PFN). Methods Fifty-four operated cases of two-part intertrochanteric (AO 31A1) were analysed and divided into two groups based on implant used (PFN 30, DHS 24). Operative details, which include blood loss and duration of surgery, were obtained from hospital records. All patients were followed up for six months and assessed for radiographic and functional outcome. The functional outcome was calculated with modified Harris hip score and Parker mobility score. Results There was no significant difference in the operative parameters (p > 0.05) between DHS and PFN. The average blood loss for DHS and PFN was 202.5 ml and 198 ml respectively while operative duration was 136 min and 126 min, respectively. All patients had good functional outcome at the end of six months with average Harris hip score of 69.7 and Parker score of 8. No difference was found between the two surgeries in terms of functional outcome as well (p > 0.05). Conclusion There is no conclusive evidence to show that PFN is superior to DHS in the treatment of two-part intertrochanteric (31A1) fracture. Both DHS and PFN are equally effective in treatment of such fractures.

[Trochanteric and subtrochanteric fractures]

Proximal femoral fractures are one of the most common fractures, particularly in older people. The most common cause is a falling event due to dizziness and gait insecurity. In most cases prompt surgical treatment is necessary to achieve early mobilization and to reduce the risk of mortality. The aim is a stable osteosynthesis and patient-centered care. A great variety of implants are available for this purpose. Furthermore, perioperative management is important to prevent further problematic events, such as delirium, reoccurrence of falling events and to diagnose and adequately treat a pre-existing osteoporosis.

Risk factors of fixation failure in basicervical femoral neck fracture: Which device is optimal for fixation?

BACKGROUND

Basicervical femur neck fracture (FNF) is a rare type of fracture, and is associated with increased risk of fixation failure due to its inherent instability. The purpose of this study was (1) to investigate the incidence of fixation failure and (2) to determine risk factors for fixation failure in basicervical FNF after internal fixation.

METHODS

To identify basicervical FNF with a minimum of 12 months follow-up, we retrospectively reviewed records of 3217 patients who underwent hip fracture surgery from May 2003 to March 2016. Among the identified 77 patients with basicervical FNF, 69 patients were followed up for at least 12 months. We evaluated the rate of collapse of fracture site and reoperation due to fixation failure. We performed a multivariable analysis to determine risk factors associated with fracture site collapse and fixation failure.

RESULTS

Among the 69 patients with basicervical FNF, 17 (24.6%) showed collapse of fracture site, and 6 (8.6%) underwent conversion to arthroplasty because of fixation failure. In the multivariable analysis, use of extramedullary plating with a sliding hip screw was an independent significant risk factor for both collapse of fracture site (odds ratio 6.84; 95% confidence interval 1.91-24.5, p = 0.003) and fixation failure (odds ratio 12.2; 95% confidence interval 1.08-137.7, p = 0.042).

CONCLUSIONS

Basicervical FNF treated with extramedullary plate with a sliding hip screw is more likely to fail than that treated with intramedullary nail with a helical blade. Our results suggested that intramedullary nail with a helical blade is more recommended for basicervical FNF compared with extramedullary plate with a sliding hip screw.

LEVEL OF EVIDENCE

III, Retrospective cohort study.