A new classification of TKA periprosthetic femur fractures considering the implant type

Double plating is a suitable option for periprosthetic distal femur fracture compared to single plate fixation and distal femoral arthroplasty

Aims

The purpose of this study was to compare reoperation and revision rates of double plating (DP), single plating using a lateral locking plate (SP), or distal femoral arthroplasty (DFA) for the treatment of periprosthetic distal femur fractures (PDFFs).

Methods

All patients with PDFF primarily treated with DP, SP, or DFA between 2008 and 2022 at a university teaching hospital were included in this retrospective cohort study. The primary outcome was revision surgery for failure following DP, SP, or DFA. Secondary outcome measures included any reoperation, length of hospital stay, and mortality. All basic demographic and relevant implant and injury details were collected. Radiological analysis included fracture classification and evaluation of metaphyseal and medial comminution.

Results

A total of 111 PDFFs (111 patients, median age 82 years (interquartile range (IQR) 75 to 88), 86% female) with 32 (29%) Su classification 1, 37 (34%) Su 2, and 40 (37%) Su 3 fractures were included. The median follow-up was 2.5 years (IQR 1.2 to 5.0). DP, SP, and DFA were used in 15, 66, and 30 patients, respectively. Compared to SP, patients treated with DP were more likely to have metaphyseal comminution (47% vs 14%; p = 0.009), to be low fractures (47% vs 11%; p = 0.009), and to be anatomically reduced (100% vs 71%; p = 0.030). Patients selected for DFA displayed comparable amounts of medial/metaphyseal comminution as those who underwent DP. At a minimum follow-up of two years, revision surgery for failure was performed in 11 (9.9%) cases at a median of five months (IQR 2 to 9): 0 DP patients (0%), 9 SP (14%), and 2 DFA (6.7%) (p = 0.249).

Conclusion

Using a strategy of DP fixation in fractures, where the fracture was low but there was enough distal bone to accommodate locking screws, and where there is metaphyseal comminution, resulted in equivalent survival free from revision or reoperation compared to DFA and SP fixation.

Retrograde intramedullary nail fixation with oblique fixed angle screws versus locking plates in periprosthetic supracondylar fractures after total knee arthroplasty

PURPOSE

Common surgical procedures in the treatment of periprosthetic distal femur fractures (PPFF) include osteosynthesis with fixed angle locking plates (LP) and retrograde intramedullary nails (RIN). This study aimed to compare LPs to RINs with oblique fixed angle screws in terms of complications, radiographic results and functional outcome.

METHODS

63 PPFF in 59 patients who underwent treatment in between 2009 and 2020 were included and retrospectively reviewed. The anatomic lateral and posterior distal femoral angle (aLDFA and aPDFA) were measured on post-surgery radiographs. The Fracture Mobility Score (FMS) pre- and post-surgery, information about perceived instability in the operated leg and the level of pain were obtained via a questionnaire and previous follow-up (FU) examinations in 30 patients (32 fractures).

RESULTS

The collective (median age: 78 years) included 22 fractures treated with a RIN and 41 fractures fixed with a LP. There was no difference in the occurrence of complications (median FU: 21.5 months) however the rate of implant failures requiring an implant replacement was higher in fractures treated with a LP (p = 0.043). The aPDFA was greater in fractures treated with a RIN (p = 0.04). The functional outcome was comparable between both groups (median FU: 24.5 months) with a lower outcome in the post-surgery FMS (p =  < 0.001).

CONCLUSION

Fractures treated with RIN resulted in an increased recurvation of the femur however the rate of complications and the functional outcome were comparable between the groups. The need for implant replacements following complications was higher in the LP group.

Primary and Periprosthetic Distal Femur Fractures in Older Adults: No Difference in 12-Month Mortality and Patient-Reported Outcomes

OBJECTIVES

To compare fracture incidence, mortality, and patient-reported health outcomes at 6 and 12 months postinjury between primary and periprosthetic distal femur fractures in older adults.

METHODS

A registry-based cohort study was conducted including all adults 70 years of age or older registered by the Victorian Orthopaedic Trauma Outcomes Registry who experienced a primary or periprosthetic distal femur fracture between 2007 and 2017. Outcomes included mortality and health status (Three-Level European Quality of Life-Five Dimensions Scale [EQ-5D-3L]) collected at 6 and 12 months postinjury. All distal femur fractures were confirmed by radiological review. Multivariable logistic regression was conducted to report associations between fracture type and mortality and health status.

RESULTS

A final cohort of 292 participants was identified. Overall mortality for the cohort was 29.8%, and no significant differences were found in mortality rate or EQ-5D-3L outcomes between fracture types (ie, primary vs. periprosthetic). A large proportion of participants reported problems across all EQ-5D-3L domains at 6 and 12 months postinjury, with slightly worse outcomes in the primary fracture group.

CONCLUSIONS

This study reports high mortality and poor 12-month outcomes in an older adult cohort with both periprosthetic and primary distal femur fractures. Given these poor outcomes, fracture prevention and a greater focus on long-term rehabilitation is needed in this cohort. In addition, the involvement of an ortho-geriatrician should be considered as a routine component of care.

LEVEL OF EVIDENCE

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

Treatment of supracondylar periprosthetic femoral fractures with retrograde intramedullary nailing versus distal femoral plating: A systematic review and meta-analysis of current evidence

BACKGROUND

Supracondylar periprosthetic fractures, when amenable to fixation, can be treated by either retrograde intramedullary nailing (RIMN) or plating. There is paucity of evidence regarding the superiority of one fixation method over the other. This review aims to determine which fixation method leads to better functional outcomes and perioperative complications.

HYPOTHESIS

Superiority of intramedullary nailing in terms of fracture healing and surgical complications when compared to distal femoral plating.

MATERIALS AND METHODS

Using PRISMA guidelines, a systematic search was performed. Studies which reported comparative outcome data following the two interventions were included. Qualitative data analysis and narrative synthesis were reported. Pooled comparisons were conducted when similar quantifiable outcomes were reported in a minimum of three studies.

RESULTS

A total of 151 records were generated by the search. Eight studies met the eligibility criteria so were included in the final analysis. The studies comprised a total of 407 cases, with a follow up period ranging from 1 to 15 years. 252 cases were treated with plate fixation and 155 with RIMN. All studies were mitigated by heterogeneity and methodological limitations. The review showed marked variation in descriptive fracture classifications. Narrative data synthesis was conducted. Although guarded by the methodological limitations of individual studies, outcomes showed that mean time to union was equivalent; 5.88 months for RIMN compared to 6.75 months in plating, standardised mean difference=0.28 (95% CI -0.02-0.58). Similarly, no statistically significant differences were reported between RIMN and plating for deep infection (OR:1.41 95%CI 0.40-5.00) and revision surgery (OR: 0.74, 95%CI 0.39-1.41).

DISCUSSION

Clinical outcomes showed a tendency that favours intramedullary nailing; however, generalisation of results was not possible. Future priority must be awarded to higher quality research in the form of a collaborative multicentre observational studies to delineate appropriate major diagnostic categories, ultimately informing a large comparative trial using condition specific validated outcome measures.

LEVEL OF EVIDENCE

III, meta-analysis.

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.

KNEE PERIPROSTHETIC FRACTURES IN THE ELDERLY: CURRENT CONCEPT

Periprosthetic fractures around total knee arthroplasty in elderly represent an emerging cause of implant revision and their incidence seems destined to further increase in the upcoming years, considering the ever-increasing number of implanted prostheses. These are complex injuries with very high complication rates. It has been estimated that the incidence of femoral periprosthetic fractures after T.K.A. ranged between 0,3 to 2,5%, but increases up to 38% when considering revision T.K.A. Patient-related risk factors for T.K.A. periprosthetic fracture (T.K.A.P.F.) include osteoporosis, age, female sex, revision arthroplasty and peri-implant osteolysis. The grate debate concerns the choice of the most appropriate fixation device for T.K.A.P.F.: closed or open reduction with internal fixation with either locked plate or intramedullary nail is the most commonly used for treating these fractures. Success of these methods depends on the fracture pattern, the stability of implants, and the patient’s bone quality which is often poor in elderly, thus resulting in high complication rates. Conversely, a revision of T.K.A. (R.T.K.A.) should be considered in case of prosthetic component instability, severe comminution or metaphyseal extension of the fracture (that precludes a good fixation), previous treatments failure and severe malalignment of T.K.A. Instead megaprosthesis and allograft-prosthesis composite are necessary in case of sever bone loss. Considering the variability of the clinical scenario of T.K.A.P.F., this complex injury requires and experienced and comprehensive approach based on both facture fixation and/or revision arthroplasty.

Reliability of current classification systems for periprosthetic distal femur fractures

INTRODUCTION

This study aims to determine which Periprosthetic Distal Femur Fracture (PDFF) classification system is the most reliable. The secondary aim was to determine which classification system correlated most accurately with the surgical management recommended and delivered.

METHODS

Between 2011 and 2019, 83 patients with 83 PDFFs that extended to the femoral component of a total knee arthroplasty (TKA) were retrospectively identified from a trauma database. Minimum follow-up was 1 year. Age, BMI, time from TKA, operative management, and Nottingham Hip Fracture Scores were collected, and AP and lateral radiographs used to classify all fractures using seven established classification systems by two observers blinded to management. In patients treated operatively (n = 69), preoperative radiographs were reviewed by two surgeons with expertise in trauma and knee revision who recommended fixation or distal femoral replacement (DFR) requirement.

RESULTS

Mean age was 80.7 years (SD9.4) and 50 (84.7%) were female. PDFFs occurred at a mean 9.5 years (SD5.2) after primary TKA. Mean follow-up was 3.8 years (SD2.9). Management was fixation in 47, DFR in 22 and non-operative for 14. The Fakler classification demonstrated highest interobserver reliability (ICC=0.948), followed by the Rorabeck (ICC=0.903), UCS (ICC=0.850) and Chen (ICC=0.906). The Neer classification demonstrated weakest agreement (ICC=0.633). Overall accuracy of predicting DFR requirement (as determined by two experts) was highest for the Fakler system (83.9%). Compared with actual management delivered the Rorabeck system was most accurate (94.1%). Multivariate regression demonstrated that the ultimate need for DFR (n = 22) was independently associated with medial comminution (HR 2.66 (1.12-6.35 95%CI), p = 0.027) and fractures distal to the anterior flange and posterior condyle of the femoral component (HR 2.45 (1.13-5.31), p = 0.024).

CONCLUSION

The Fakler classification showed highest interobserver agreement and was most accurately predictive of the management recommended by two experts. No classification system accurately predicted the fractures that required DFR, and none included medial comminution which was independently associated with DFR requirement. There remains a need for a PDFF classification system that reliably guides operative management of PDFFs.

Comparable Outcomes Between Native and Periprosthetic Fractures of the Distal Femur

Despite the rising prevalence of arthroplasty and aging population, limited data exist regarding differences in periprosthetic fracture clinical outcomes compared with native counterparts. This study compares differences in hospital treatment, morbidity, and mortality associated with periprosthetic distal femur fractures at an urban level 1 trauma center. We retrospectively reviewed all adult AO/OTA type 33 fractures (526) that presented to our institution between 2009 and 2018. In total, 54 native and 54 periprosthetic fractures were matched by age and gender. We recorded demographics, operative measures, length of stay (LOS), discharge disposition, and mortality. We used McNemar's and paired t-tests for analysis where appropriate (p < 0.05) (IBM SPSS Statistics for Windows, Version 26.0. Armonk, NY; IBM Corp.). The average age at injury was 74 years ± 12 (native) compared with 73 years ± 12 (periprosthetic). After 1:1 matching, the groups had similar body mass index (31.01 vs. 32.98, p = 0.966 for native and periprosthetic, respectively) and mechanisms of injury with 38 native and 44 periprosthetic (p = 0.198) fractures from low-energy falls. Both groups had 51/54 fractures managed with open reduction internal fixation with a locking plate. The remaining were managed via amputation or intramedullary nail fixation. Mean operative time (144 minutes (±64) vs. 132 minutes (±62), p = 0.96) and estimated blood loss (319 mL (±362) vs. 289 mL (±231), p = 0.44) were comparable between the native and periprosthetic groups, respectively. LOS: 9 days ± 7 (native) versus 7 days ± 5 (periprosthetic, p = 0.31); discharge disposition (to skilled nursing facility/rehab): n = 47 (native) versus n = 43 (periprosthetic, p = 0.61); and mortality: n = 6 (native) versus n = 8 (periprosthetic, p = 0.55). No significant differences were observed. We found no statistical differences in morbidity and mortality in periprosthetic distal femur fractures treated over 10 years at a level 1 trauma center. Native and periprosthetic AO/OTA type 33 distal femur fractures are serious injuries with similar outcomes at a level 1 trauma center.

Treatment Algorithm of Periprosthetic Femoral Fracturens

Introduction. The ever-expanding indications for total hip arthroplasty are leading to more implants being placed in younger as well as in older patients with high functional demand. Also, prolonged life expectancy is contributing to an overall increment of periprosthetic femoral fractures. The Vancouver classification has been the most used for guiding the surgeon choice since its proposal in 1995. Fractures occurring over a hip femoral implant can be divided into intra-operative and post-operative PFFs, and their treatment depends on factors that may severely affect the outcome: level of fracture, implant stability, quality of bone stock, patients’ functional demand, age and comorbidities, and surgeon expertise. There are many different treatment techniques available which include osteosynthesis and revision surgery or a combination of both. The goals of surgical treatment are patients’ early mobilization, restoration of anatomical alignment and length with a stable prosthesis and maintenance of bone stock. Significance. The aim of this review is to describe the state-of-the-art treatment and outcomes in the management of PFFs. We performed a systematic literature review of studies reporting on the management of PFFs around hip stems and inter-prosthetic fractures identifying 45 manuscripts eligible for the analysis. Conclusions. PFFs present peculiar characteristic that must be considered and special features that must be addressed. Their management is complex due to the extreme variability of stem designs, the possibility of having cemented or uncemented stems, the difficulty in identifying the “real” level of the fracture and the actual stability of the stem. As a result, the definition of a standardized treatment is unlikely, thereby high expertise is fundamental for the surgical management of PPFs, so this kind of fractures should be treated only in specialized centres with both high volume of revision joint arthroplasty and trauma surgery.

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.

Treatment of B1 Distal Periprosthetic Femur Fractures

The burden of periprosthetic distal femoral fractures is projected to increase accordingly with the increase in total knee arthroplasties (TKAs) performed globally in the future. Less invasive plating and intramedullary (IM) nailing techniques still seem to provide similar outcomes based on current literature. Double-plating and combination techniques may prove to be beneficial in the future pending further large-scale studies but currently have not demonstrated superiority over single plating and IM nailing based on current evidence. Distal femoral replacement may provide a useful option for future treatment, provided it is performed by a trained knee arthroplasty surgeon.

Bilateral Periprosthetic Knee Fracture with the Right Floating Total Knee and Left Periprosthetic Patella Fracture Management Strategy: A Case Report

Introduction:

Periprosthetic fractures (PPFs) in total knee replacement are an uncommon condition. The floating knee injury around total knee arthroplasty (TKA) is even rare and poses challenges in management. Incidence is increasing due to growing primary joint arthroplasties and revision procedures. We report a case of bilateral PPF with a floating total knee.

Case Report:

A 74-year-old female involved in a violent car accident sustained bilateral knee injuries, facial, and hand injury. In the emergency room, the initial resuscitation and trauma protocol stabilization were done and she was provisionally immobilized for her limb injuries. She presented with the right-sided floating total knee involving periprosthetic periarticular comminuted distal femur fracture and midshaft comminuted fracture tibia fibula. The patient also had left knee lower pole periprosthetic patellar fracture. The patient had a history of bilateral TKA around 2 years back. She underwent surgical management of the right floating total knee by stabilization of distal femur fracture and tibial shaft fracture fixation with locking plates. She underwent primary autologous bone grafting for both fracture sites. The left knee patellar fracture was managed conservatively in a brace. At 8 months follow-up, the patient was pain free and had consolidation of fractures. The patient walked without any walking aids. At 18 months, she had regained her pre-injury functional status.

Conclusion:

Each fracture in a floating total knee injury is unique and treatment should be decided based on individual analysis and the extent of soft-tissue injuries. An uncommon occurrence highlights the complex injury patterns involving PPF requiring individualized case specific management strategy.

[Locking plate fixation of distal periprosthetic femoral fractures : Clinical outcome and mortality]

Hintergrund

Die Versorgung distaler periprothetischer Femurfrakturen (PFF) stellt aufgrund des geriatrischen Patientenkollektivs eine große interdisziplinäre Herausforderung dar und erfolgt (abhängig vom Frakturtyp) häufig mittels winkelstabiler Plattenosteosynthese (WPO), wobei bisher nur wenige Daten zum klinischen Outcome existieren. Ziel der Untersuchung ist die Identifikation von Risikofaktoren für ein schlechtes Outcome und erhöhte Mortalität.

Methoden

In dieser retrospektiven Studie wurden 36 Fälle mit distaler PFF untersucht. Eingeschlossen wurden nur Versorgungen mit WPO. Neben relevanten Vorerkrankungen (ASA-Score, Charlson Index), der Frakturmorphologie und relevante Komplikationen, wurden u.a. die 1- und 3-Jahres-Mortalität, sowie das klinische Outcome mit Hilfe des Lysholm-Scores erfasst.

Ergebnisse

Die 1- und 3- Jahres Mortalität betrug 9% bzw. 26%, wobei dies ausschließlich ASA 3 und 4 Patienten betraf. Der Lysholm Score zeigte eine hohe Variabilität (65 ± 27 Punkte) mit höheren Werten in der ASA 1-2 Subgruppe (82 vs. 63 Punkte) aber unabhängig vom Frakturtyp. Als Risikofaktoren für die 3-Jahres Mortalität konnten der präoperative ASA-Score, der Charlson Komorbiditätsindex und das Patientenalter identifiziert werden.

Diskussion

Die dargestellte Fallserie weist eine hohe absolute Mortalitätsrate auf, auch wenn diese im Vergleich zu bisher publizierten Daten, etwas geringer war. Die Rate an Sekundärdislokationen, fehlender Frakturheilung oder Folgeoperationen war ebenfalls gering. Die WPO erscheint daher als geeignete Versorgung für Frakturen mit stabiler Prothese. Jedoch besteht eine hohe Variabilität im klinischen Outcome unabhängig vom Frakturtyp, sowie signifikant erhöhte Mortalitätsraten bei vorerkrankten Patienten.

[Periprosthetic fractures: basics, classification and treatment principles]

Periprosthetic fractures (PPFx) are becoming an increasingly important topic in orthopedics and trauma surgery due to the rising number of endoprosthetic joint replacements. The recently published unified classification system (UCS) has replaced numerous historical classification systems and can be applied to all PPFx regardless of the bone or joint involved. The treatment of PPFx requires individual therapeutic concepts taking patient-dependent and patient-independent factors into consideration. The conservative treatment of PPFx is only justified in exceptional situations. In contrast, the choice between operative treatment and deciding between osteosynthesis or revision arthroplasty is particularly based on the assessment of the implant stability. In order to achieve fracture consolidation and also a good functional outcome, knowledge of the basic biomechanical principles of operative (osteosynthesis or endoprosthesis) treatment of periprosthetic fractures is necessary.

Periprosthetic tibial fractures in total knee arthroplasty - an outcome analysis of a challenging and underreported surgical issue

Background

Periprosthetic fractures after total knee arthroplasty (TKA) are an increasing problem and challenging to treat. The tibial side is commonly less affected than the femoral side wherefore few studies and case reports are available. The aim of this study was to analyze the outcome of periprosthetic tibial fractures and compare our data with current literature.

Methods

All periprosthetic tibial TKA fractures that were treated at our Level 1 Trauma Center between 2011 and 2015 were included and analyzed consecutively. The Felix classification was used to assess the fracture type and evaluation included the radiological and clinical outcome (Knee Society Score/KSS, Oxford Knee Score/OKS).

Results

From a total of 50 periprosthetic TKA fractures, 9 cases (7 female, 2 male; 2 cruciate retaining, 7 constrained TKAs) involving the tibial side were identified. The mean age in this group was 77 (65–85) years with a follow-up rate of 67% after a mean of 22 (0–36) months. The Felix classification showed type IB (n = 1), type IIB (n = 2), type IIIA (n = 4) and type IIIB (n = 2) and surgical intervention included ORIF (n = 6), revision arthroplasty (n = 1), arthrodesis (n = 1) and amputation (n = 1). The rate of adverse events and revision was 55.6% including impaired wound healing, infection and re-fracture respectively peri-implant fracture. Main revision surgery included soft tissue surgery, arthrodesis, amputation and re-osteosynthesis. The clinical outcome showed a mean OKS of 29 (19–39) points and a functional/knee KSS of 53 (40–70)/41 (17–72) points. Radiological analyses showed 4 cases of malalignment after reduction and plate fixation.

Conclusions

Periprosthetic tibial fractures predominantly affect elderly patients with a reduced bone quality and reveal a high complication rate. Careful operative planning with individual solutions respecting the individual patient condition is crucial. If ORIF with a plate is considered, restoration of the correct alignment and careful soft tissue management including minimal invasive procedures seem important factors for the postoperative outcome.