Femoral revision for periprosthetic fracture in total hip arthroplasty

Petersen M, Stürup J, Winther NS. Implant Survival of an Uncemented Modular Femoral Implant in Patients With Severe Femoral Bone Loss and 2-Stage Hip Revision

Background and Purpose: Revision total hip arthroplasty (rTHA) is a challenging procedure especially in the presence of severe bone loss where implant fixation is compromised. The aim of this study was to evaluate implant survival, clinical outcome, and midterm results in a group of complex patients after femoral revision using an uncemented modular implant design. Patients and Methods: We performed a retrospective study including 100 patients (101 hips) treated with revision THA using an uncemented modular implant design. We identified 51 hips as Paprosky types I-II and 50 hips as Paprosky III-IV bone defects. We reviewed operative reports and radiographs. Patients underwent a clinical examination to assess the Harris Hip Score (HHS) and completed patient-reported outcome measures (PROM), including the Oxford Hip Score (OHS) and the EQ-5D Visual Analog Scale (VAS). Minimum follow-up was 2 years (average, 5.8 years; range, 2.0-9.4 years). Results: Among the cases, 46 hips were revised for infection in a 2-stage procedure and 44 hips for aseptic loosening. 11 hips had periprosthetic fractures of Vancouver type B2 or B3. A total of 5 hips required revision with removal of the femoral implant and 11 patients experienced complications resulting in fracture (n = 1), dislocation (n = 10), and soft tissue revision (n = 1). The 5-year implant survival estimated by Kaplan-Meier survival analysis was 95% (95%-CI: 91%-99%). All hips had radiographic evidence of osseointegration and no one with subsidence greater than 5 mm. Additionally, 80% showed radiographic evidence of restoration of proximal femoral bone. Mean HHS was 78. Conclusion: In complex cases of revision THA, using a modular revision femoral system yielded promising results. The 5-year implant survival estimated by Kaplan-Meier survival analysis was 95% (95%-CI: 91%-99%), with all hips demonstrating radiographic evidence of osseointegration and no one with subsidence greater than 5 mm. Notably 80% showed radiographic evidence of restoration of proximal femoral bone.

Predicting extended hospital stay following revision total hip arthroplasty: a machine learning model analysis based on the ACS-NSQIP database

INTRODUCTION

Prolonged length of stay (LOS) following revision total hip arthroplasty (THA) can lead to increased healthcare costs, higher rates of readmission, and lower patient satisfaction. In this study, we investigated the predictive power of machine learning (ML) models for prolonged LOS after revision THA using patient data from a national-scale patient repository.

MATERIALS AND METHODS

We identified 11,737 revision THA cases from the American College of Surgeons National Surgical Quality Improvement Program database from 2013 to 2020. Prolonged LOS was defined as exceeding the 75th value of all LOSs in the study cohort. We developed four ML models: artificial neural network (ANN), random forest, histogram-based gradient boosting, and k-nearest neighbor, to predict prolonged LOS after revision THA. Each model's performance was assessed during training and testing sessions in terms of discrimination, calibration, and clinical utility.

RESULTS

The ANN model was the most accurate with an AUC of 0.82, calibration slope of 0.90, calibration intercept of 0.02, and Brier score of 0.140 during testing, indicating the model's competency in distinguishing patients subject to prolonged LOS with minimal prediction error. All models showed clinical utility by producing net benefits in the decision curve analyses. The most significant predictors of prolonged LOS were preoperative blood tests (hematocrit, platelet count, and leukocyte count), preoperative transfusion, operation time, indications for revision THA (infection), and age.

CONCLUSIONS

Our study demonstrated that the ML model accurately predicted prolonged LOS after revision THA. The results highlighted the importance of the indications for revision surgery in determining the risk of prolonged LOS. With the model's aid, clinicians can stratify individual patients based on key factors, improve care coordination and discharge planning for those at risk of prolonged LOS, and increase cost efficiency.

A Consecutive Series of Vancouver B2 Periprosthetic Femur Fractures Treated With Contemporary Monoblock Versus Modular Revision Stems: Clinical and Radiographic Outcomes

BACKGROUND

Tapered fluted titanium (TFT) stems are the implant design of choice for managing Vancouver B2 periprosthetic femur fractures (PFFs), producing reliable results over the past few decades. The aim of this study was to compare the radiographic and clinical outcomes of Vancouver B2 PFFs treated with contemporary monoblock versus modular TFTs.

METHODS

A consecutive series of 113 patients (72 women, 64%, mean age 70 years [range, 26 to 96]) who had a B2 PFF were treated with either a monoblock (n = 42) or modular (n = 71) TFT stem between 2008 and 2021. The mean body mass index was 30 ± 7. The mean follow-up was 2.9 years. A radiographic review was performed to assess leg length and offset restoration, endosteal cortical contact length, and stem subsidence. Kaplan-Meier analyses were used to determine survivorship without revision, reoperation, or dislocation.

RESULTS

There was no difference in the restoration of leg length (0.3 ± 8.0 mm) or offset (2.8 ± 8.2 mm) between the monoblock and modular cohorts (P > .05). Mean endosteal cortical contact length (47.2 ± 26.6 versus 46.7 ± 2 6.4 mm, P = .89) and stem subsidence (2.7 ± 3.5 versus 2.4 ± 3.2 mm, P = .66) did not differ. No difference in patient-reported outcome measures (Hip Disability and Osteoarthritis Outcome Score-Joint Replacement; Veterans RAND 12 Item Health Survey Physical and Mental; visual analog score; and Lower Extremity Activity Scale) between the groups was observed. Survivorship at 2 years free from reoperation, revision, and dislocation was 90.4, 90.3, and 97.6%, respectively, for the monoblock cohort; and 84.0, 86.9, and 90.0%, respectively, for the modular cohort.

CONCLUSIONS

No significant differences in radiographic or clinical outcomes were observed between patients treated with monoblock or modular TFTs in this large series of B2 PFFs.

Revision total hip arthroplasty for periprosthetic fracture: epidemiology, outcomes, and factors associated with success

The aging population and the increasing number of patients with primary total hip arthroplasties (THA) has equated to an increased incidence of periprosthetic fractures (PPF) of the hip. These injuries are a significant source of patient morbidity and mortality, placing a financial burden on healthcare systems worldwide. As the volume of PPF is expected to along with the growing volume of primary and revision THA, it is important to understand the outcomes and factors associated with treatment success. The choice of procedure is in large part guided by the help of the Vancouver Classification system, which is a valid and reproducible system that classifies fractures based on several factors including site of fracture, implant stability and bone stock. PPFs account for approximately 18% of revision THA (rTHA) procedures. rTHA for PPFs is commonly indicated in Vancouver B2 and B3 fractures, to bypass a lack of metaphyseal support with diaphyseal fixation. Such revisions are technically challenging and typically require urgent treatment, with inherent difficulties in patient optimization, leading to a notable rate of post-operative complications, re-revision and mortality. This article reviews epidemiology, health economics and risk factors for PPFs. It additionally reviews outcomes associated with rTHA for PPFs including peri-operative complications, indications for re-operation, rates of re-operation and rates of mortality. Finally, it aims to identify evidence-based factors that have been associated with successful management including modifiable patient-related factors, uncemented vs. cemented stems, stem design (porous coated stems vs. fluted tapered stems), modularity, dislocation and its impact on outcomes following rTHA and strategies for managing bone loss.

Periprosthetic fracture management of the proximal femur

The most common periprosthetic fractures occur around the hip. The most widely used classification is the Vancouver classification, and management requires careful planning and skill in both arthroplasty and fracture surgery. This article presents an overview of the diagnosis, classification, and management of periprosthetic fractures of the proximal femur. This work represents a summary review from Latin American Society Members of the International Orthopaedic Trauma Association.

The influence of composite bone plates in Vancouver femur B1 fracture fixation after post-operative, and healed bone stages: A finite element study

Conventional stainless steel or titanium plates are used for bone fracture fixation to provide support at fracture location. Plates with high elastic modulus reduce the transfer of compressive load at the fracture location (due to stress shielding), causing failure. The objective of the study is to find for composite bone plates with different types of fibers and varied fiber orientations for post-operative (PO) and healed bone (HB) conditions which can reduce the stress shielding. Femur fracture fixation was constructed with 12 holes narrow type with metal and composite bone plates. The fracture gap was constructed with soft bone region for post-operative (PO) condition and harder bone for healed bone (HB). Composite bone plates with different configurations (fiber directions) and types (thickness and width) were analyzed to study the stress distribution and movement in the fracture location. The models were analyzed and the stresses in plate and callus, movement and strain in axial and shear direction in both metal and composite bone plates were studied. The metal and composite plates (carbon fiber/epoxy, fiberglass/epoxy, and flax/epoxy) used for most common Vancouver type B1 fracture to observe the biomechanical behavior of different models in PO and HB condition. The FE simulation on different configurations and types of composite plates provide in-depth idea about choosing the suitable composite bone plate. There are variations in behavior for varying types and configurations, but the performance of most of the plates are either better or similar to that of metal plate, except the plates with higher width.

Modular or Monolithic Tapered Fluted Prostheses for Periprosthetic Fractures: Which One Could Work for You?

Periprosthetic fracture around a femoral component is a potentially devastating complication after total hip arthroplasty. Surgical treatment is often technically demanding and requires a thorough understanding of fracture care and revision joint reconstruction. Advancements in femoral component designs for revision total hip arthroplasty have improved management of this challenging complication. It is important for surgeons to understand which femoral component design might best suit their needs. We present an overview of revision total hip arthroplasty in the setting of periprosthetic fracture, focusing on comparing the 2 most popular femoral component revision models, the modular and monolithic tapered fluted conical prostheses.

Periprosthetic hip fractures: an update into their management and clinical outcomes

The Vancouver classification is still a useful tool of communication and stratification of periprosthetic fractures, but besides the three parameters it considers, clinicians should also assess additional factors.

Combined advanced trauma and arthroplasty skills must be available in departments managing these complex injuries.

Preoperative confirmation of the THA (total hip arthroplasty) stability is sometimes challenging. The most reliable method remains intraoperative assessment during surgical exploration of the hip joint.

Certain B1 fractures will benefit from revision surgery, whilst some B2 fractures can be effectively managed with osteosynthesis, especially in frail patients.

Less invasive osteosynthesis, balanced plate–bone constructs, composite implant solutions, together with an appropriate reduction of the limb axis, rotation and length are critical for a successful fixation and uneventful fracture healing.

Cite this article: EFORT Open Rev 2021;6:75-92. DOI: 10.1302/2058-5241.6.200050