Periprosthetic fractures of the knee: a comprehensive review

Clinical differences between periprosthetic and native distal femur fractures: a comparative observational study

INTRODUCTION

The incidence of periprosthetic distal femur fractures (PDFF) is increasing as the number of total knee replacements becomes more common. This study compared the demographics, fracture characteristics, treatment, and outcomes of periprosthetic versus native distal femur fractures (NDFF).

MATERIALS AND METHODS

This was a retrospective cohort study of patients ≥ 18 who underwent surgical fixation of NDFF or PDFF from 2012 to 2020 at a level-1 trauma center. The main variables collected included demographics, AO/OTA fracture classification, fixation construct, concomitant fractures, polytrauma rates, bone density, and reduction quality. Primary outcomes were unexpected return to the operating room (UROR), hospital length of stay, and quality of reduction. T-tests, Fisher's exact tests, and multivariate analyses were used for statistical analysis.

RESULTS

209 patients were identified, including 70 PDFF and 139 NDFF. PDFF patients were elderly females (81%) with isolated (80%) and comminuted (85%) 33 A.3 (71%) fractures. NDFF patients included 53% females, were commonly middle-aged, and displayed comminuted (92%) 33 C.2 fractures. 48% of NDFF patients had concomitant fractures. Intramedullary nailing was the primary fixation for both groups, followed by nail-plate combination (37%) for PDFF and lateral locking plates (21%) for NDFF. NDFF patients experienced significantly longer hospital stays, higher UROR rates, and worse quality of reduction (p < 0.05). PDFF patients had a significantly greater prevalence of low bone density (p < 0.05).

CONCLUSION

PDFF occur as isolated injuries with significant metaphyseal comminution in elderly females with low bone quality. NDFF commonly occurs in younger patients with less metaphyseal comminution and concomitant fractures. Intramedullary nailing was the most common treatment for both groups, although preference for nail-plate combination fixation is increasing. NDFF type 33 C fractures are at greater risk of UROR.

Postoperative Bisphosphonates Use is Associated with Reduced Adverse Outcomes After Primary Total Joint Arthroplasty of Hip and Knee: A Nationwide Population-Based Cohort Study

Bisphosphonates have been associated with a decreased risk of revision surgery after total joint arthroplasty of the hip or knee (TJA) because of their effects on decreased periprosthetic bone loss and prosthetic migration. However, the results in the early literature are inconsistent, and the influence of bisphosphonates on associated complications and subsequent TJA remains unknown. This study investigated the association between the use of bisphosphonates and the risk of adverse outcomes after primary TJA. This matched cohort study utilized the National Health Insurance Research Database in Taiwan to identify patients who underwent primary TJA over a 15-year period (January 2000-December 2015 inclusive). Study participants were further categorized into two groups, bisphosphonate users and nonusers, using propensity score matching. The Kaplan-Meier curve analysis and adjusted hazard ratios (aHRs) of revision surgery, adverse outcomes of primary surgery and subsequent TJA were calculated using Cox regression analysis. This study analyzed data from 6485 patients who underwent total hip arthroplasty (THA) and 20,920 patients who underwent total knee arthroplasty (TKA). The risk of revision hip and knee arthroplasty was significantly lower in the bisphosphonate users than in the nonusers (aHR, 0.54 and 0.53, respectively). Furthermore, the risk of a subsequent total joint arthroplasty, adverse events and all-cause mortality were also significantly reduced in the bisphosphonate users. This study, involving a large cohort of patients who underwent primary arthroplasties, revealed that bisphosphonate treatment may potentially reduce the risk of revision surgery and associated adverse outcomes. Furthermore, the use of bisphosphonates after TJA is also associated with a reduced need for subsequent arthroplasty.Research Registration Unique Identifying Number (UIN): ClinicalTrials.gov Identifier-NCT05623540 ( https://clinicaltrials.gov/show/NCT05623540 ).

Evaluation of painful total knee arthroplasty: an approach based on common etiologies for total knee arthroplasty revision

A differential diagnosis with emphasis on the common indications for revision should be utilized in the workup of painful total knee arthroplasty (TKA). The physician should identify the exact etiology of the patient's pain to maximize outcomes from treatment. Evaluation for infection should be completed using the Musculoskeletal Infection Society (MSIS) criteria. When common causes of revision TKA do not appear to be the cause of the pain, less likely causes should be not be ignored. Further advancements such as pressure sensing devices may be able to improve patient satisfaction and decrease the incidence of pain following TKA.

Patella Fracture After Total Knee Arthroplasty: A Review

The management and underlying causes of patellar periprosthetic fractures (PPF) after total knee arthroplasty (TKA) constitute an issue of growing importance given the rising frequency of these procedures. Patella periprosthetic fractures, though relatively rare, pose significant challenges and are a frequent indication for revision surgeries. Despite a decrease in overall incidence, PPFs remain the second most common type of periprosthetic fractures after TKA. Several factors have been identified and associated with patient-specific factors, surgical technique errors, and implant-related causes. Currently extensor apparatus integrity, bone stock, and component loosening are the major concerns and indications for the selective treatment approach. In this study, a thorough review of the existing literature was performed summarizing the epidemiology, clinical manifestation, treatment approach, and functional outcome of PPF. This review aims to underline the significance of such predisposing factors, point out the severity of PPF, and offer insights into the optimal intra- and post-operative management of the patella.

Adequate bone healing after supplementary fixation of periprosthetic total knee arthroplasty fractures using Luque cerclage wiring: a retrospective case series

PURPOSE

Cerclage wiring is a well-known supplemental fixation technique that can be used in many types of fractures. With the tendency toward minimally invasive approaches in the management of periprosthetic total knee arthroplasty (TKA) fractures, and with absence of a dedicated study that reports the results of cerclage wiring in TKA fractures in particular, the aim of this retrospective study is to report the outcomes of supplementary cerclage wiring using simple Luque wires in fractures of distal femur associated with TKA.

METHOD

Eighteen cases, with a mean age of 77.2 years had complete follow-up data and had their radiographs and clinical data assessed for this study. Patients received cerclage wiring along with plates, retrograde nailing or around cracked femoral shaft overlying revision TKA femoral stem during the surgical management of periprosthetic TKA distal femur fractures.

RESULTS

Fracture healing with adequate callus formation occurred in all 18 cases at a mean of 11.4 weeks postoperatively. None of the cases had any vascular injury, and after a mean clinical follow-up of 51 weeks, none of the cases had nonunion or hardware complications. One case had postoperative periprosthetic infection that developed 8 months after full fracture healing and had a two-stage revision using revision stemmed TKA and protective cerclage wiring with successful eradication of infection.

CONCLUSION

Supplementary cerclage wiring in distal femur TKA fractures can aid in enhanced bone healing with minimal complications, provided that adequate reduction and rigid fixation were achieved. This study reflects the level of evidence IV.

Periprosthetic patella fractures in total knee replacement and revision surgeries: how to diagnose and treat this rare but potentially devastating complication-a review of the current literature

PURPOSE

Periprosthetic patella fractures (PPPFs) are infrequent but potentially devastating complications after total knee arthroplasty (TKA) and revision TKA (rTKA). These fractures may occur both in resurfaced and un-resurfaced patella. This review summarizes the current literature on PPPFs to help orthopedic surgeons diagnose and treat this uncommon but extremely challenging TKA complication.

METHODS

A comprehensive search was performed in three databases: PubMed, SCOPUS, and EMBASE. All relevant information was retrieved and summarized in this narrative review.

RESULTS

In the studies analyzed, there is a general trend in favor of nonsurgical treatment, except for implant loosening or extensor lag with extensor apparatus disruption, because surgery is often associated with poor clinical outcomes and high complication rates.

CONCLUSION

PPPF is a rare but catastrophic event in TKA and rTKA, occurring mainly in a reconstructed patella. Patient-, implant-, and surgical technique-related factors contribute to its multifactorial etiopathogenesis. Prevention plays a crucial role in reducing the PPPFs rate. Conservative management is the treatment of choice due to high surgery complication rates unless implant loosening, or extensor apparatus disruption occurs.

Diagnosis and Management of Intraoperative Periprosthetic Fractures in Primary Total Knee Arthroplasty

Intraoperative periprosthetic fracture is an uncommon but notable complication that can occur during primary total knee arthroplasty. These fractures may occur at various stages during the procedure, including surgical exposure, implant preparation, implant trialing, and final implantation. Management of femoral and tibial fractures necessitates intraoperative recognition, including attentiveness of preoperative patient and surgical risk factors. This comprehensive review article focuses on the patient and surgical risk factors, diagnosis, management, and outcomes related to intraoperative fractures during primary total knee arthroplasty.

Periprosthetic distal femoral fractures after total knee replacement treated by ORIF. Mid to long-term follow-up study in 12 patients

Periprosthetic fractures following total knee arthroplasty are a quite uncommon traumatic lesion that often are present in elderly patients with osteoporosis and comorbidities. The most common periprosthetic fracture affects the distal femur. The main internal fixation techniques are ORIF with a locking plate and retrograde intramedullary nailing. In the present study, we report the medium-long term results in 12 patients with a distal femoral periprosthetic fracture stabilized with a locking plate. We reviewed 12 patients affected by a periprosthetic distal femur fracture surgically treated between 2010 and 2016 by ORIF using a locking compression plate after an average follow-up of 5.75 years. The average age of the patients at diagnosis was 78 years. The mean interval time between knee arthroplasty and distal femoral fracture was 8.25 years. Clinical results were assessed using the WOMAC score, while radiographic results according to Beals and Tower's criteria. All fractures of our series were type II according to the Rorabeck and Taylor classification. At follow-up, the WOMAC score ranged from 40.5 to 76.5 points (average 53.92). Radiographic results, according to Beals and Tower's criteria, were excellent in 5 patients and good in 7. All patients returned to their previous daily activities. We believe that reduction and internal fixation with a locking plate is a surgical option of treatment that provides satisfactory clinical and radiological results in Rorabeck type II periprosthetic distal femoral fractures.

Treatment of Bifocal Periprosthetic Fractures above and below a Knee after Tumor using Spanning Ilizarov Device: A Case Report

Introduction

Multiple treatment options and internal and external devices have been recommended for periprosthetic fractures management around total knee arthroplasty.

Case Report

We present the case of the high-energy bifocal periprosthetic fractures of the femur and the tibia after total knee prosthesis following excision of a tumor. One of the fractures was an open tibial fracture Gustilo Type IIIB and the other - comminuted subtrochanteric fracture of the femur with extrusion of periprosthetic cement pieces out from the bone defect. The Ilizarov circular external fixator was used for the skeletal stabilization and early functional treatment in this compound case.

Conclusion

The use of Ilizarov external fixator for patients with complex periprosthetic fractures, who present severe technical difficulties in bone stabilization, especially by concomitant severe soft-tissue damage after high-energy injuries, is a good surgical alternative.

Should megaprosthesis implants be a viable option in elderly patients after distal femur and periprosthetic distal femur fractures?-a retrospective cohort study

Background

Distal femur fractures (DFF) and periprosthetic distal femur fractures (PDFF) in elderly patients are challenging to manage, often requiring the use of distal femur replacement (DFR) implants to manage severe bone loss and comminution. The study's main purpose was to analyze outcomes and complications of DFR implant after DFF or PDFF at our institution to understand the feasibility and reliability of this treatment considering a review of the current literature.

Methods

Fourteen consecutive patients undergoing total knee replacement with megaprosthesis implant from January 1st, 2017 to January 1st, 2021, at our institution were retrospectively analyzed. Inclusion criteria were age ≥65 years and DFF or PDFF after primary total knee arthroplasties (TKA) implantation. Patient-reported outcome measures (PROMs) such as Knee Society Score (KSS) and Oxford Knee Score (OKS) were analyzed, as well as radiographic pre- and post-operative imaging. Complications were recorded from the early postoperative period to the last follow-up.

Results

Nine patients were diagnosed with PDFF and five with DFF. At a mean follow-up of 30.7 months (range, 12 to 69 months), the mean KSS knee score was 79.5±11.2; the mean KSS function score was 69.0±17.9. The mean OKS was 31.6±8.9. The mean age at intervention was 82.1±7.6 years. Two delayed wound closures and one chronic prosthetic joint infection (PJI) were observed. No death was observed at the last follow-up.

Conclusions

Megaprosthesis implants could be a suitable option in elderly, arthritic patients diagnosed with complicated DFFs and PDFFs, allowing joint function preservation and a rapid return to daily activities. DFR remains an intervention burdened by devastating complications that must be considered in the treatment choice.

Intraoperative Fractures Sustained During Total Knee Arthroplasty: A Critical Analysis Review

» While the occurrence of postoperative periprosthetic fractures around total knee arthroplasties (TKAs) are well reported, little is known about intraoperative fractures that occur during TKA. Intraoperative fractures during TKA can occur in femur, tibia, or patella. It is a rare complication with an incidence of 0.2% to 4.4%.» Risk factors of periprosthetic fractures include osteoporosis, anterior cortical notching, chronic corticosteroid use, advanced age, female sex, neurologic disorders, and surgical technique.» Fractures can potentially occur at any stage of the TKA including exposure, bone preparation, placement of trial components, cementation, insertion of the final components, and seating of the polyethylene insert. Forced flexion during trialing increases the risk for patella fracture, tibial plateau, or tubercle fractures especially when there is under resection of the bone.» Management guidelines for these fractures are lacking with current options being observation, internal fixation, the use of stems and augments, increasing constraint of the prosthesis, implant revision, and modifying the postoperative rehabilitation.» Finally, the outcomes of intraoperative fractures are not well reported in the literature.

Managing periprosthetic tibia fractures: International perspectives

Knee arthroplasty, both total knee and unicompartmental, has had a significant impact on millions of patients globally. Although satisfaction is usually high, complications such as periprosthetic fracture are increasingly common. Distal femur periprosthetic fractures are relatively well researched and understood in comparison with periprosthetic proximal tibia fractures (PTFs). The management of PTFs is essentially an evidence-free area. This review explores the literature (or lack thereof) and integrates cases from Australia and Japan. As it stands, there is scant literature relating to all facets of PTFs, including, most concerningly, the management of them. Larger studies are required to help further investigate this important interface between arthroplasty and orthopaedic trauma. As a guide, those with loose prostheses will likely benefit most from revision total knee arthroplasty, while those with well-fixed prostheses can be managad according to the fracture with homage paid to the presence of the prosthesis. The use of periarticular locked plates is likely a better option over conventional large or small fragment plates. Nonoperative management is a viable option for selected individuals and can be associated with favorable outcomes.

The Impact of Epilepsy on Complication Rates After Total Joint Arthroplasty: A Propensity Score-Matched Cohort Study

BACKGROUND

It is unclear how epilepsy may affect total joint arthroplasty outcomes. The purpose of this study is to analyze the impact of epilepsy on prosthesis-related complications following primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

A retrospective cohort study was conducted using a national database. Patients who have epilepsy underwent a primary THA (n = 6,981) and TKA (n = 4,987) and were matched 1:4 (THA, n = 27,924; TKA, n = 19,948). Rates of low-energy falls and prosthesis-related complications within 2 years postoperatively were compared for patients who did and did not have epilepsy with multivariable logistic regression.

RESULTS

After primary TKA, patients who have epilepsy exhibited significantly higher rates of aseptic revision (4.3% versus 3.5%, odds ratio [OR] 1.21, P = .017) and revision for prosthetic joint infection (1.8% versus 1.3%, OR 1.29, P = .041). THA patients who have epilepsy exhibited significantly higher rates of prosthetic dislocation (3.2% versus 1.9%, OR 1.54, P < .001), periprosthetic fracture (2.2% versus 0.8%, OR 2.39, P < .001), and aseptic loosening (1.7% versus 1.1%, OR 1.40, P = .002). Rates of low-energy falls within 2 years after TKA (14.1% versus 6.4%, OR 2.19, P < .001) and THA (33.6% versus 7.5%, OR 5.95, P < .001) were also significantly higher for patients who have epilepsy.

CONCLUSION

Epilepsy was associated with significantly higher rates of falls (P < .001) and prosthesis-related complications after primary THA (P < .05) and TKA (P < .05). Precautions should be implemented in this population during intraoperative and perioperative decision-making to reduce complication risk.

LEVEL OF EVIDENCE

Level III.

Biomechanical analysis of different fixation methods for Rorabeck II supracondylar femoral fractures after total knee arthroplasty

BACKGROUND

Locking plate (LP) and retrograde intramedullary nailing (RIMN) are widely used to fix Rorabeck II supracondylar femoral fractures after total knee arthroplasty (TKA). The biomechanical properties of the implant used for treatment influence its longevity. Therefore, we aimed to evaluate the biomechanical stability of different fixations using finite element analysis.

METHODS

Seven finite element models (FEMs) were established, including LP groups (short LP, long LP, and double LP), RIMN groups (short RIMN and long RIMN), and mixed groups (long LP with short RIMN and long LP with long RIMN). The stress of the implants around the fracture area was calculated to evaluate the biomechanical stability under loads.

RESULTS

Stress was mainly distributed around the fracture area in all models. The stress-shielding phenomenon was most evident in the short LP. The trend in maximum equivalent stress values of implants around the fracture area for the seven internal fixations was: short LP (324.63 MPa) > short RIMN (306.37 MPa) > long LP (275.06 MPa) > long RIMN (262.74 MPa) > double LP (203.19 MPa) > long LP with short RIMN (124.42 MPa) > long LP with long RIMN (112.41 MPa). We found that the double LP can better disperse the stress than a single LP, and a long LP with long RIMN can prevent stress concentration and make the stress distribution more uniform.

CONCLUSION

From the perspective of biomechanics, long LP with long RIMN can stabilize fractures and avoid stress concentration in Rorabeck II supracondylar femoral fractures after TKA.

Novel classification system for periprosthetic distal femoral fractures: a consideration for comminution

PURPOSE

Comminution is an aspect of periprosthetic distal femoral fractures (PDFFs) that can influence postoperative outcomes and treatment selection, but is not included in current classification systems. We propose a new classification system for PDFFs based on comminution and cortical reads. This study aims to prove its reliability and efficacy to predict fracture severity and guide treatment.

METHODS

A retrospective chart review of patients treated with single or dual locking plates for PDFFs was performed. Two fellowship-trained orthopedic joint reconstruction specialists used available imaging to classify each PDFF as either type 1 (minimal or no comminution allowing for reconstruction of medial and lateral cortices), type 2 (comminution reasonably allowing for reconstruction of either medial or lateral cortex), and type 3 (extensive comminution not allowing reasonable reconstruction of medial or lateral cortex). Each PDFF was then analyzed for radiographic outcomes including lateral distal femoral angle (LDFA) and the posterior distal femoral angle (PDFA).

RESULTS

Interobserver reliability assessed by Cohen's Kappa statistic was 0.707, and average intraobserver reliability was 0.843, showing substantial reliability. Type 3 PDFFs had greater varus deformity than type 1 (p = 0.0457) or 2 (0.0198).

CONCLUSION

The proposed classification system accounts for comminution, demonstrates strong interobserver and intraobserver reliability, and can be used to guide treatment in regard to single versus dual plating.

LEVEL OF EVIDENCE

Retrospective comparative study, Level IV.

Distal Femoral Replacement for Periprosthetic Fractures After TKA: Australian Orthopaedic Association National Joint Replacement Registry Review

BACKGROUND

Distal femoral replacement (DFR) is a potential treatment option following periprosthetic fracture (PPF) of a total knee arthroplasty (TKA). However, there is limited literature regarding implant survivorship and complication rates. The aim of this study was to examine patient demographics and trends in usage, implant survivorship and modes of failure, and patient mortality following DFR for PPF captured by a national joint replacement registry.

METHODS

A retrospective registry review was performed using data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). In total, 306 DFR were performed for PPF of a known primary TKA. Eighty-five percent of patients were female, and the mean age was 76.4 years. Kaplan-Meier estimates of implant and patient survivorship were performed.

RESULTS

The number of DFR performed for PPF has doubled over the past five years. The cumulative percent second revision rate at six years was 12%. The most common indications for revision were infection (37%) and aseptic loosening (33%). Patient survivorship after DFR was 97% and 83% at five and ten years, respectively.

CONCLUSION

A national registry review has identified the increasing prevalence of DFR for PPF after primary TKA and demonstrated implant survivorship of 88% at midterm follow-up. Surgeons may consider DFR as an acceptable and durable treatment option.

LEVEL OF EVIDENCE

Level III - Case Series.

Tibial periprosthetic fractures in Total Knee Arthroplasty - A scoping review

Background

Periprosthetic tibial fractures in Total Knee Arthroplasty are much less commonly seen than femoral fractures, and there is a paucity of available literature and management recommendation for these fractures. We aimed to identify the relevant and up-to-date literature on this subject to analyse the incidence, risk factors, and management recommendations.

Methods

A literature search was done on the databases of PubMed and SCOPUS using appropriate keywords. All the published literature in the English language was included for this review.

Results

We included 21 studies comprising 260 tibial periprosthetic fractures (91 intra-operative (35%) and 169 (65%) post-operative or delayed fractures). Only 5.9% of these fractures were managed conservatively. Whereas 98 cases (58%) were managed with open reduction and internal fixation (ORIF) with plating, 19 (11.2%) were managed with revision TKA. Seventeen cases (10%) were managed with minimally invasive percutaneous plate osteosynthesis (MIPPO), and 8 (4.7%) were managed with intramedullary nailing. Less than 6% of cases were managed with other means, viz. megaprosthesis (n = 4), arthrodesis (n = 5), amputation (n = 1), and external fixator (n = 1).

Conclusion

Intraoperative fractures accounted for one-third of the fractures in our review. A majority of the delayed periprosthetic fractures were treated with surgical intervention. The most preferred surgical treatment method was ORIF of fractures using locking plates (either open or MIPPO). Revision TKA or megaprosthesis was used in cases with the loosened implants in association with the fracture.

Level of evidence

IV.

New Classification for Periprosthetic Distal Femoral Fractures Based on Locked-Plate Fixation Following Total Knee Arthroplasty: A Multicenter Study

BACKGROUND

This study aimed to establish a new classification using locked-plate fixation for periprosthetic distal femoral fracture (PDFF) following total knee arthroplasty (TKA) and to determine when dual locked-plate fixation is necessary through defining this classification.

METHODS

One-hundred fifteen consecutive PDFFs that underwent operative treatment were reviewed from 2011 to 2019 with minimum 1-year follow-up. Most PDFFs were fixed with single or dual locked-plate fixations using the minimally invasive plate osteosynthesis technique. Based on preoperative radiographs, PDFFs were classified according to the level of main fracture line relative to the anterior flange of femoral component: type I and II, main fracture line located proximal and distal to the anterior flange; and type III, component instability regardless of fracture line requiring revisional TKA. Furthermore, type II fractures were subclassified based on the direction of fracture beak as follows: type II_L, lateral-beak; type II_M, medial-beak. The incidence, treatment methods, and complications were analyzed according to the classification.

RESULTS

Incidences of type I, II_L, II_M, and III were 64.4%, 8.7%, 24.3%, and 2.6%, respectively. Meanwhile, most PDFFs in type I and II were treated with lateral single locked-plate fixations, except for type II_M, which was treated with either single or dual locked-plate fixations. Overall complications were significantly higher in type II (28.9%) than in type I (10.8%, P = .019). In type II_M, bone union-related complications were significantly higher in single locked-plate fixation (50.0%) than in dual locked-plate fixation (5.6%; P = .013).

CONCLUSION

The new classification provides practical and obvious strategies for the treatment of PDFF following TKA using locked-plate fixation. For type II_M fracture, dual plate fixation is necessary to prevent fixation failure or nonunion.

Fracture in an arthrodesed Charcot's knee joint

Charcot's joint is a type of neuro-arthropathy, where asymmetrical damage of the involved joint happens haphazardly, without following any described pattern. We present a rare case of Charcot's joint involving the knee joint in an adult male following spina bifida. His knee joint was successfully fused after two surgeries. Later, he sustained a fracture through the arthrodesis after a fall, which we managed surgically. The fracture through the knee arthrodesis was managed surgically by an open reduction and internal fixation, using a 14-hole broad low contact dynamic compression locking plate with bone grafting. Union was achieved at the knee arthrodesis site in 6 months. Fracture through a fused knee requires surgical management. Re-arthrodesis was done using a stable fixation. Postoperative rehabilitation should include protected weight bearing with braces and splints until a sound bony union is achieved.

Very Distal Femoral Periprosthetic Fractures: Replacement Versus Fixation: A Systematic Review

OBJECTIVES

To synthesize all-cause reoperations and complications data as well as secondary clinical and functional outcomes, after the management of very distal femur periprosthetic fractures (vDFPFs) in a geriatric patient population with either a distal femoral locking plate (DFLP) or distal femoral replacement (DFR).

DATA SOURCES

MEDLINE, Embase, and Web of Science were searched for English language articles from inception to March 16, 2020, in accordance to the PRISMA guidelines.

STUDY SELECTION

Studies reporting the management of vDFPFs in adults older than 65 years with either a DFLP or DFR were included. To ensure this review solely focused on very distal femoral periprosthetic fractures, only fractures of the following classifications were included: (1) Lewis and Rorabeck type II or III, (2) Su and Associates' Classification of Supracondylar Fractures of the Distal Femur type III, (3) Backstein et al type F2, and/or (4) Kim et al type II or III.

DATA EXTRACTION

Three reviewers independently extracted data from the included studies. Study validity was assessed using the methodological index for nonrandomized studies (MINORS), a quality assessment tool for nonrandomized controlled studies in surgery.

DATA SYNTHESIS

Twenty-five studies with 649 vDFPFs were included for analysis. There were 440 knees in the DFLP group (mean age range: 65.9-88.3 years) and 209 knees in the DFR group (mean age range: 71.0-84.8 years). Because of the literature's heterogeneity, the data were qualitatively synthesized.

CONCLUSIONS

vDFPFs in the elderly treated with DFR underwent fewer reoperations relative to DFLP (0%-45% vs. 0%-77%, respectively). Time to weight-bearing was observably shorter in DFR studies relative to DFLP studies. Functional outcomes and postoperative range of motion indicated a trend for DFLP knees to outperform DFR knees. Future research should include prospective studies and cost-effectiveness evaluations to better understand the utility of DFR for these fractures.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

A Review of Periprosthetic Tibial Fractures: Diagnosis and Treatment

Periprosthetic fracture occurring during or after total knee arthroplasty is a rare injury. Literature concerning periprosthetic tibial factures is sparse, and there is limited guidance for evidence-based management. This review aims to provide readers with an overview of the epidemiology, risk factors, and classification of these fractures. Management includes nonoperative treatment of nondisplaced fractures, fixation for those with stable implants, and revision for those with loose implants.

Review of patient-reported outcomes in periprosthetic distal femur fractures after total knee arthroplasty: a plate or intramedullary nail?

Purpose

This study reviewed the literature regarding the patient-reported treatment outcomes of using either open reduction and internal fixation (ORIF) with a plate and screw system or intramedullary nail (IMN) fixation for periprosthetic distal femur fractures around a total knee arthroplasty.

Methods

A total of 13 studies published in the last 20 years met the inclusion criteria. The studies included 347 patients who were allocated to ORIF (n = 249) and IMN (n = 98) groups according to the implants used. The primary outcome measures were the Knee Society Score or the Western Ontario and McMaster Universities osteoarthritis index. The secondary outcome measures included knee range of motion and the rates of complications, including non-union, malunion, infection, revision total knee arthroplasty, and reoperation. Statistical significance was set at P < 0.05.

Results

The mean Knee Society Scores of ORIF and IMN groups were 83 and 84, respectively; the mean postoperative range of motion of the knee were 99° and 100°, respectively (P < 0.05); the non-union rates were 9.4 and 3.8%, respectively (P > 0.05); the malunion rates were 1.8 and 7.5%, respectively (P < 0.05); surgical site infection rates were 2 and 1.3%, respectively (P > 0.05); the reoperation rates were 9.6 and 5.1%, respectively (P > 0.05); and revision rates of total knee arthroplasty were 2 and 1%, respectively (P > 0.05).

Conclusion

Based on the patient-reported outcome assessments, both ORIF with a plate and screw system and IMN fixation are well-accepted techniques for periprosthetic distal femur fractures around a TKA, and they produce similar functional outcomes.

Incidence and Risk Factors of In-Hospital Prosthesis-Related Complications Following Total Knee Arthroplasty: A Retrospective Nationwide Inpatient Sample Database Study

Objective

To examine the incidence and risk factors of in‐hospital prosthesis‐related complications (PRCs) following total knee arthroplasty (TKA) using a large‐scale national database.

Methods

A retrospective database analysis was performed based on Nationwide Inpatient Sample (NIS) from 2005–2014. Patients who underwent TKA were included. The recruited cases were divided into two groups according to the occurrence of PRCs. Patient demographics (age, sex, and race), hospital characteristics (type of admission and payer, and bedsize, teaching status, location, and region of hospital), length of stay (LOS), total charges during hospitalization, in‐hospital mortality, comorbidities, and perioperative complications were analyzed.

Results

A total of 1,227,244 TKAs were captured from the NIS database. There were 8484 cases of in‐hospital PRCs after TKA and the overall incidence was 0.69%, with a slight downward trend annually. Periprosthetic joint infection (PJI) was the main category among PRCs (0.20%), followed by mechanical loosening (0.04%), dislocation (0.02%), and periprosthetic fracture (PPF) (0.01%). Patients suffered from in‐hospital PRCs were 3 years younger (64 years vs 67 years) and 6.51% more likely to be male (43.60% vs 37.09%) compared to the nonaffected population (P < 0.0001). Additionally, patients experiencing in‐hospital PRCs after TKA were 2.11% less likely through elective admission (92.07% vs 94.18%) while 2.34% more likely in teaching hospital (45.53% vs 43.19%) than those without these complications (P < 0.0001). Furthermore, the occurrence of in‐hospital PRCs was associated with longer LOS (4 days vs 3 days; P < 0.0001), more total charges ($53,418 vs $41,204, P < 0.0001), and higher in‐hospital mortality (0.30% vs 0.07%; P < 0.0001). Multivariate logistic regression was performed to identify independent risk factors of in‐hospital PRCs after TKA which included younger age, male, non‐elective admission, teaching hospital, deficiency and chronic blood loss anemia, coagulopathy, congestive heart failure, depression, diabetes with chronic complications, fluid and electrolyte disorders, pulmonary circulation disorders, metastatic cancer, and weight loss. Besides, in‐hospital PRCs after TKA were associated with secondary osteoarthritis, inflammatory arthritis, prior knee arthroscopy, acute renal failure, acute myocardial infarction, deep vein thrombosis, sepsis, transfusion, and wound dehiscence.

Conclusion

It is beneficial to study the risk factors of in‐hospital PRCs after TKA to ensure the appropriate management and optimize consequences although a relatively low incidence was identified.

PLCγ1 inhibition combined with inhibition of apoptosis and necroptosis increases cartilage matrix synthesis in IL-1β-treated rat chondrocytes

Osteoarthritis (OA) is an age‐related, chronic degenerative disease. With the increasing median age of the population, this disease has become an important public health problem. New, disease‐modifying therapies are needed. A potential novel molecular target is phospholipase Cγ1 (PLCγ1), a critical enzyme with important functions including calcium signaling regulation and cell proliferation. In rat chondrocytes treated with IL‐1β (20 ng·mL⁻¹ for 36 h), inhibition of PLCγ1 with U73122 (2 μm for 12 h) increased levels and expression of the cartilage matrix components Collagen2 and Aggrecan. This beneficial effect of PLCγ1 inhibition was counteracted by increased chondrocyte apoptosis and necroptosis, increased cell death, and increase levels of ROS, all potentially negative for OA. Combined treatment of IL‐1β + U73122‐treated chondrocytes with inhibitors of apoptosis (Z‐VAD, 10 μm) and necroptosis (Nec‐1, 30 μm) enhanced the increases in levels and expression of Collagen2 and Aggrecan, and prevented the increases in cell death and ROS levels. These results suggest that PLCγ1 inhibition may be a viable approach for an OA therapy, if combined with targeted inhibition of chondrocyte apoptosis and necroptosis.

Peri-prosthetic trans-patellar fractures after Total knee Arthroplasty: a case series and review of literature

Abstract

Peri-prosthetic patella fracture is the second most common peri-prosthetic fracture after total knee arthroplasty. This report presented the treatment results in 6 patients with peri-prosthetic patella fractures. From January 2015 to February 2019, six patients with peri-prosthetic patella fractures were treated. The mean age at surgery was 64 years (range, 48–72 years). Four patients with displaced fractures were treated surgically, and two patients with non-displaced fractures were treated non-surgically. Outcomes were assessed in terms of motion, functional knee score, and Knee Society score. The mean follow-up period lasted 16 months (range: 12–20 months). The average arc of motion was 110° (range: 80°–130°). The mean functional knee score was 77 (range: 70–87). The mean Knee Society score was 84 (range: 75–89). The non-surgical treatment may be a good choice for non-displaced peri-prosthetic patella fractures. For displaced fractures, surgical treatments yielded good functional outcomes.

Level of evidence

IVa

Periprosthetic femoral re-fractures pathogenesis, classification, and surgical implications

Periprosthetic femoral re-fractures (PFRFs) represent an emerging challenge for orthopaedic surgeons, since their incidence is growing in the last years, but very few experiences about their management have been currently published. The present study aims to (1) introduce, for the first time, an etiologic classification for PRFRs and (2) to provide surgical and pharmacological tips for the correct management of these injuries. Periprosthetic femoral re-fractures (PFRFs) could be classified into traumatic-PFRFs (T-PFRFs) and pathological-PFRFs (P-PFRFs). T-PFRFs, i.e. the "true" periprosthetic re-fractures, present as new fracture lines occurring proximally or distally to a previous periprosthetic fracture, that has correctly healed. They are generally unpredictable injuries but, in selected cases, it is possible to predict them by analyzing the construct used in the treatment of the previous periprosthetic fracture. P-PFRFs, on the other hand, define re-fractures occurring on a previous periprosthetic non-union or delayed union: the new fracture line appears in the same district of the old one. According to the etiologic factors influencing the P-PFRFs pathogenesis, it is possible to define re-fractures caused by mechanical failures, biological failures, septic failures and multifactorial failures, i.e., a combination of the previously mentioned concerns. A successful postoperative outcome, following the surgical management of PFRFs, requires the correct identification of all the underlying causes, which should be promptly and appropriately managed.

[Periprosthetic fractures around the knee]

BACKGROUND

Periprosthetic fractures of the knee joint are complex injuries and frequently represent a challenge for the surgeon.

OBJECTIVE

The aim of this review is to present and discuss the current classification and treatment options for periprosthetic knee fractures.

MATERIAL AND METHODS

A selective review of the existing literature on periprosthetic fractures around the knee was performed in PubMed. The various classifications and treatment regimens are discussed with respect to the advantages and disadvantages and from this knowledge a new algorithm was developed.

RESULTS

The classifications of periprosthetic fractures have changed in recent years and have been replaced by a uniform fracture classification; however, not only the radiological evaluation of the fractures is crucial to determine the treatment regimen for periprosthetic fractures. A thorough evaluation of the inserted endoprosthesis should be carried out in order to be able to decide between the treatment options of osteosynthesis and revision arthroplasty. Treatment options are available for osteosynthesis and revision arthroplasty that enable a safe treatment of these complex injuries.

CONCLUSION

Periprosthetic fractures of the knee joint are complex injuries, requiring a thorough preoperative planning and an interdisciplinary treatment with trauma and endoprosthetic expertise.