Distal femoral replacement for selective periprosthetic fractures above a total knee arthroplasty

Weight-bearing Restrictions after Distal Femur Fractures - Review of Current Literature

The incidence of distal femur fractures increases in the geriatric patient. The primary treatment goal in these fractures is early mobilisation to prevent secondary injuries associated with immobility. In light of the increasing spectrum of therapeutic options for postoperative fracture treatment, including double plating, nail-plate combination and distal femur replacement as postoperative treatments, weight-bearing recommendations are becoming increasingly important. The aim of this study was thus to analyse the weight-bearing recommendations and associated therapy results within the literature of the past 9 years and compare the recommendations to our own approach.

Megaprosthesis in Non-Oncologic Settings-A Systematic Review of the Literature

Modular megaprostheses (MPs) are commonly used after bone-tumor resection, but they can offer a limb salvage solution in massive bone defects. The aim of this systematic review of the Literature is to provide a comprehensive data collection concerning the use of MPs in non-oncologic cases, and to provide an overview of this topic, especially from an epidemiologic point of view. Three different databases (PubMed, Scopus, and Web of Science) were searched for relevant articles, and further references were obtained by cross-referencing. Sixty-nine studies met the inclusion criteria, reporting on cases of MP in non-oncologic cases. A total of 2598 MPs were retrieved. Among these, 1353 (52.1%) were distal femur MPs, 941 (36.2%) were proximal femur MPs, 29 (1.4%) were proximal tibia MPs and 259 (10.0%) were total femur MPs. Megaprostheses were most commonly used to treat periprosthetic fractures (1158 cases, 44.6%), in particular in the distal femur (859, 74.2%). Overall, complications were observed in 513 cases (19.7%). Type I (soft tissue failures) and type IV (infection) according to the Henderson classification were the most frequent (158 and 213, respectively). In conclusion, patients with severe post-traumatic deformities and/or significant bone loss who have had previous septic complications should be considered as oncologic patients, not because of the disease, but because of the limited therapeutic options available. The benefits of this treatment include relatively short operative times and immediate weight-bearing, thus making MP particularly attractive in the lower limb.

Periprosthetic distal femur fractures around total knee replacements: A comprehensive review

With a growing number of patients undergoing total knee replacements globally, coupled with an elderly population, the incidence of periprosthetic fractures around total knee replacements is increasing. As such, this is a highly topical subject that is gaining increasing interest within the orthopaedic community. This review provides a narrative synthesis of the most contemporary literature regarding distal femoral periprosthetic fractures. We review the related epidemiology, initial patient evaluation, the evolution and relevance of the classification systems and treatment options, particularly related to endoprosthetics and hybrid fixation constructs. The latest orthopaedic evidence related to this topic has been included.

Optimal surgical treatment for periprosthetic distal femoral fractures after total knee arthroplasty: a Bayesian-based network analysis

BACKGROUND

The surgical methods for periprosthetic distal femoral fractures (PDFFs) after total knee arthroplasty included locking compression plate (LCP), retrograde intramedullary nailing (RIMN), and distal femoral replacement (DFR). However, the optimal treatment remains controversial. We performed a network meta-analysis (NMA) to provide the optimal surgical method for PDFFs.

MATERIALS AND METHODS

Electronic databases, including Embase, Web of Science, Cochrane Library, and PubMed, were searched for studies that compared LCP, RIMN, and DFR for PDFFs. The quality of the included studies was assessed according to the Newcastle-Ottawa scale. Pairwise meta-analysis was performed by Review Manager version 5.4. The NMA was conducted in Aggregate Data Drug Information System software version 1.16.5. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) for postoperative complications and reoperations.

RESULTS

A total of 19 studies and 1198 patients were included, of whom 733 for LCP, 282 for RIMN, and 183 for DFR. Pairwise meta-analysis comparing LCP to RIMN and LCP to DFR showed no significant difference in complications and reoperations except that RIMN had a higher risk of malunion comparing to LCP (OR 3.05; 95% CI 1.46-6.34; P = 0.003). No statistically significant effects were found in the NMA of overall complications, infection, and reoperation. However, results of rank probabilities showed that DFR ranked best in overall complications and reoperation, RIMN ranked best in infection but worst in reoperation, and LCP ranked worst in infection and middle in reoperation.

DISCUSSION

We found similar complication rate and reoperation rate between LCP, RIMN, and DFR. The results of rank probabilities favored DFR, and further studies with high-level evidence are expected to verify the optimal surgical method for PDFFs.

LEVEL OF EVIDENCE

Level II; network meta-analysis.

Distal Femoral Replacement versus Operative Fixation for Periprosthetic Distal Femur Fractures: A Systematic Review and Meta-Analysis

BACKGROUND

Open reduction and internal fixation (ORIF) and distal femoral replacement (DFR) have been utilized in the management of periprosthetic distal femur fractures. At present, much of the literature has been limited to small retrospective series. The purpose of the current investigation was to present the results of pooled data to determine the complication rates associated with ORIF and DFR.

METHODS

Publications from 2010 to 2020 describing 10 or more periprosthetic distal femur fractures treated with ORIF (ie, single plate, intramedullary nail, and dual fixation) or DFR were included, resulting in 32 publications and 1,258 fractures (977 ORIF and 281 DFR). Occurrence of surgical complications, reoperations, and medical complications were evaluated and compared.

RESULTS

The rate of surgical complications (ORIF versus DFR, 20.5 versus 14.9%, P = 1.0) and reoperations (12.9 versus 12.5%, P = 1.0) following DFR were similar. However, pooled analyses demonstrated that patients treated with DFR had a higher medical complication rate (ORIF versus DFR, 8.5 versus 23.1%, P = .0006).

CONCLUSION

ORIF and DFR for the treatment of periprosthetic distal femur fractures have similar surgical complication and reoperation profiles. While this review found an increased rate of medical complication following DFR, there are limitations in quality reporting in the literature, which should be considered when interpreting the study's findings. Failed ORIF can be salvaged with DFR, but the difficulty of this reoperation is dependent on the ORIF technique that was used. With future prospective studies, this review can help guide management of these fractures.

Does distance from joint line influence complications after distal femur fractures in native and periprosthetic knees?

BACKGROUND

Distal femur fractures are projected to increase in incidence secondary to an aging population and growing utilization of total knee arthroplasty. Surgical management is the standard of care, but optimal treatment for far distal fractures is still unclear. Our study investigates if there are distal femur fractures too distal to be treated with lateral locked plating in periprosthetic fractures.

METHODS

One hundred and ten consecutive patients treated with locked plating for distal femur fractures around a total knee replacement were identified using CPT codes. Fractures were classified by length of the distal fracture segment and Su classification. Complications studied were nonunion, malunion, infection, further fracture related surgery, readmission within 90 days, and mortality within 1 year of surgery. Sixty six fractures met inclusion criteria of 180 days of follow-up or sustaining a complication prior to180 days.

RESULTS

The size of the distal fracture segment and Su classification did not correlate with increased complication rate in periprosthetic distal femur fractures.

CONCLUSIONS

There was no difference between complications following lateral locked plating of distal femur fractures based on the size of the distal fracture segment in periprosthetic fractures. Lateral locked plating is an effective treatment modality for these fractures regardless of how distal the fracture extends.

Distal femoral replacement or internal fixation for management of periprosthetic distal femur fractures: A systematic review

BACKGROUND

The number of periprosthetic fractures above a total knee arthroplasty continues to increase. These fractures are associated with a high risk of morbidity and mortality. Techniques for addressing these fractures include open reduction internal fixation (ORIF) and revision arthroplasty, including distal femoral replacement (DFR). The primary aim of this review is to compare mortality and reoperation rates between ORIF and DFR when used to treat periprosthetic distal femur fractures.

METHODS

A systematic review including MEDLINE, Embase and Cochrane Library databases was completed from inception to April 10, 2021. Studies including a comparator cohort were meta-analyzed.

RESULTS

Fourteen studies were identified for inclusion, of which, five had sufficient homogeneity for inclusion in a meta-analysis. 30-day and 2-year mortality was 4.1% and 14.6% in the DFR group. There was no statistically significant difference between ORIF and DFR (log Odds-Ratio (OR) = -0.14, 95 %CI: -0.77 to 0.50). The reoperation rate in the DFR group was 9.3% versus 14.8% for ORIF, with no difference between groups (log OR = 0.10, 95 %CI: -0.59 to 0.79). There was no difference in rates of deep infection (log OR = 0.22, 95 %CI: -0.83 to 1.28). Direct comparison of functional outcomes was not possible, though did not appear significant.

CONCLUSION

DFR in the setting of periprosthetic distal femur fractures is equivalent to ORIF with respect to mortality and reoperation rate and thus a safe and reliable treatment strategy. DFR may be more reliable in complex fracture patterns where the ability to obtain adequate fixation is difficult.

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.

Clinical Outcomes Following Distal Femur Replacement for Periprosthetic Distal Femur Fractures: A Systematic Review and Meta-Analysis

BACKGROUND

Management of periprosthetic distal femur fractures (PDFFs) is often complicated by poor bone quality and limited bone stock making fixation attempts challenging and prone to failure. Distal femoral replacement (DFR) is being used to treat such injuries although outcome data are mostly from small case series. We sought to systematically review the literature on DFR for PDFF to summarize their outcomes.

METHODS

PubMed, MEDLINE (EBSCO), and Cochrane Central Database were searched to identify reports of PDFFs treated with DFR. Articles reporting on 5 or more knees were systematically reviewed for clinical function, complications, and mortality. Random effects meta-analysis was used to create summary estimates and publication bias also assessed.

RESULTS

Of 287 identified and screened articles, 15 were included, 14 retrospective, reporting on 352 knees. Following DFR, 87% (95% confidence interval [CI] 71-95) of patients were able to ambulate. The mean postoperative Knee Society Score was 80 (95% CI 77-84). The risk of periprosthetic joint infection was 4.3% (95% CI 2.2-8.2). One-year postoperative mortality rate was 10% (95% CI 6-18). There was some evidence of publication bias with a trend toward smaller studies reporting lower infection risk and mortality.

CONCLUSION

DFR for PDFFs is associated with high functional outcomes and a relatively modest risk of infection. The periprosthetic joint infection and 1-year mortality rates reported here should be considered lower bounds estimates due to publication bias and loss to follow-up. Further investigation of long-term outcomes following DFR for PDFFs is warranted though short-term functional outcomes are promising.

Cost-effectiveness of fixation versus arthroplasty for geriatric distal femur fractures

INTRODUCTION

Geriatric distal femur fractures are challenging to treat. The high mortality rate associated with a loss of mobility in this population has led some authors to compare distal femur fractures to femoral neck fractures with respect to the importance of rapidly regaining mobility in the geriatric population. Acute distal femur replacement has been advocated by some as a preferred treatment over internal fixation because arthroplasty may facilitate a more rapid return to a patient's baseline mobility level. The purpose of this study was to systematically review the literature on the costs and outcomes of fixation and arthroplasty in the geriatric distal femur fracture population and to employ decision modeling techniques to generate evidence-based treatment recommendations.

METHODS

A systematic literature review of clinical studies published since 2000 was conducted to synthesize the available data on outcomes, reoperation rates, and mortality rates after fixation or arthroplasty for distal femur fractures in patients with an average age greater than 70 years. A Markov decision analysis model was created. Costs, health state utilities, reoperation rates, and mortality rates were derived from the systematic literature review and publicly available data. The model was analyzed via probabilistic statistical analysis as well as sensitivity analyses with a willingness-to-pay threshold set at $100,000 per QALY and a 5-year time horizon.

RESULTS

From a US societal perspective, fixation was associated with a greater quality of life benefit (2.44 QALYs vs. 2.34 QALYs) and lower cost ($25,556 vs. $65,536) compared with distal femur replacement for geriatric distal femur fractures. Probabilistic analysis demonstrated that 82 in 100 model outcomes favored fixation over arthroplasty and 18 in 100 model outcomes favored distal femur replacement. Sensitivity analyses demonstrated that this result was robust to small deviations in the cost and functional outcome variables in the model.

CONCLUSION

Compared to distal femur replacement, ORIF is likely to be a more cost-effective treatment for distal femur fractures in the geriatric patient population, though this recommendation is tempered by the relatively low quality of evidence available on the comparative functional outcomes of these treatments.

Distal Femur Replacement Versus Open Reduction and Internal Fixation for Treatment of Periprosthetic Distal Femur Fractures: A Systematic Review and Meta-Analysis

OBJECTIVE

To compare complications and functional outcomes of treatment with primary distal femoral replacement (DFR) versus open reduction and internal fixation (ORIF).

DATA SOURCES

PubMed, Embase, and Cochrane databases were searched for English language studies up to May 19, 2020, identifying 913 studies.

STUDY SELECTION

Studies that assessed complications of periprosthetic distal femur fractures with primary DFR or ORIF were included. Studies with sample size ≤5, mean age <55, nontraumatic indications for DFR, ORIF with nonlocking plates, native distal femoral fractures, or revision surgeries were excluded. Selection adhered to the PRISMA criteria.

DATA EXTRACTION

Study quality was assessed using previously reported criteria. There were 40 Level IV studies, 17 Level III studies, and 1 Level II study.

DATA SYNTHESIS

Fifty-eight studies with 1484 patients were included in the meta-analysis. Complications assessed {incidence rate ratio [IRR] [95% confidence interval (CI)]: 0.78 [0.59-1.03]} and reoperation or revision [IRR (95% CI): 0.71 (0.49-1.04)] were similar between the DFR and ORIF cohorts. The mean knee range of motion was greater in the ORIF cohort (DFR: 90.47 vs. ORIF: 100.36, P < 0.05). The mean Knee Society Score (KSS) (DFR: 79.41 vs. ORIF: 82.07, P = 0.35) and return to preoperative ambulatory status were similar [IRR (95% CI): 0.82 (0.48-1.41)].

CONCLUSIONS

In comparing complications among patients treated for periprosthetic distal femur fracture with DFR or ORIF, there was no difference between the groups. There were also no differences in functional outcomes, although knee range of motion was greater in the ORIF group. This systematic review and meta-analysis highlights the need for future prospective trials evaluating the outcomes of these divergent treatment strategies.

LEVEL OF EVIDENCE

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

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.

Early complications and reoperation rates are similar amongst open reduction internal fixation, intramedullary nail, and distal femoral replacement for periprosthetic distal femur fractures: a systematic review and meta-analysis

BACKGROUND

Our purpose was to perform a systematic review and meta-analysis to evaluate complication and revision rates for periprosthetic distal femur fractures (PPDFF) treated with: (1) ORIF using periarticular locking plates (ORIF), (2) retrograde intramedullary nail (IMN), and (3) distal femoral replacement (DFR).

METHODS

Systematic review of the literature was performed to identify eligible studies (N = 52). Identified treatment groups were: ORIF (N = 1205 cases), IMN (N = 272 cases), and DFR (N = 353 cases). Median follow-up was 30 months (range 6-96 months). Primary outcomes were: (1) major complication rates and (2) reoperation rates over the follow-up period. Secondary outcomes were incidence of deep infection, periprosthetic fracture, mortality over the follow-up period, 1-year mortality, non-union, malunion, delayed union, and hardware failure. Data for primary and secondary outcomes were pooled and unadjusted analysis was performed. Meta-analysis was performed on subset of individual studies comparing at least two of three treatment groups (N = 14 studies). Odds-ratios and their respective standard errors were determined for each treatment group combination. Maximum likelihood random effects meta-analysis was conducted for primary outcomes.

RESULTS

From the systematic review, major complication rates (p = 0.55) and reoperation rates (p = 0.20) were not significantly different between the three treatment groups. DFR group had a higher incidence of deep infection relative to IMN and ORIF groups (p = 0.03). Malunion rates were higher in IMN versus ORIF (p = 0.02). For the meta-analysis, odds of major complications were not significantly different between IMN versus DFR (OR 1.39 [0.23-8.52]), IMN versus ORIF (OR 0.86 [0.48-1.53]), or the ORIF versus DFR (OR 0.91 [0.52-1.59]). Additionally, odds of a reoperation were not significantly different between IMN versus DFR (OR 0.59 [0.08-4.11]), IMN versus ORIF (OR 1.26 [0.66-2.40]), or ORIF versus DFR (OR 0.91 [0.51-1.55]).

CONCLUSIONS

There was no difference in major complications or reoperations between the three treatment groups. Deep infection rates were higher in DFR relative to internal fixation, malunion rates were higher in IMN versus ORIF, and periprosthetic fracture rates were higher in DFR and IMN versus ORIF.

Distal Femoral Replacements for Acute Comminuted Periprosthetic Knee Fractures: Satisfactory Clinical Outcomes at Medium-Term Follow-up

Background

Fracture fixation techniques of comminuted periprosthetic distal femoral fractures have high risk of complications. The aim of this study was to evaluate short- to medium-term outcomes of comminuted periprosthetic distal femoral fractures treated with distal femoral replacements (DFR) at a tertiary arthroplasty unit.

Methods

Retrospective consecutive study of all patients who underwent DFR for periprosthetic fractures with minimum 2-year follow-up between 2010 and 2018. Clinical outcomes, surgical complications, revision for any cause, loosening, Knee Society Score and mortality data were collected at final follow-up.

Results

Thirty patients with average age 81 years (range, 65-90; 6 males and 24 females) were included. All had comminuted fractures (Rorabeck type-2/3). All patients had cemented DFRs. Three patients (10%) with multiple comorbidities died postoperatively. Average time from admission to being fit for discharge was 9 days (range, 3-14). Clinical outcomes and follow-up were available for 27 patients with a median follow-up duration of 4 years (2-13 years). Complication rate was 7.4% with one reoperation, change of polyethylene insert. None of the components have been revised to date. Average Knee Society Score at final follow-up was 78 (range, 57-92) with median arc of motion flexion-extension being 100° (range, 60°-125°).

Conclusions

In our experience, DFRs for comminuted periprosthetic fractures allow immediate mobilization and rehabilitation leading to satisfactory clinical outcomes with low complication rate for this challenging group of patients.

Level of evidence

level IV.

The Treatment of Periprosthetic Distal Femoral Fractures After Total Knee Replacement: A Critical Analysis Review

Periprosthetic distal femoral fracture after total knee arthroplasty carries substantial morbidity and mortality regardless of fixation technique. Surgical treatment is favored in most patients compared with conservative therapy because of high rates of nonunion, malunion, and reoperation after casting or bracing. Internal fixation techniques including retrograde intramedullary nailing and locked plating are favored for surgical treatment in most fractures when bone stock in the distal fragment allows for appropriate fixation. In the setting of deficient distal femoral bone stock or femoral component loosening, revision arthroplasty with distal femoral replacement is the favored technique. Further studies with regard to the use of intramedullary nailing, locked plating, and distal femoral replacement are necessary to refine the indications for each technique and to define the use of combinations of these fixation techniques.

Demographics, Treatment, and Cost of Periprosthetic Femur Fractures: Fixation Versus Revision

Introduction:

Periprosthetic femur fractures (PPFX) are complications of both total hip and knee arthroplasty and may be treated with open reduction and internal fixation (ORIF) or revision arthroplasty. Differences in treatment and fracture location may be related to patient demographics and lead to differences in cost. Our study examined the effects of demographics and treatment of knee and hip PPFXs on length of stay (LOS) and cost.

Methods:

Of all, 932 patients were identified with hip or knee PPFXs in the National Inpatient Sample from January 2013 to September 2015. Age, gender, race, mortality, comorbidity level, LOS, total cost, procedure type, geographic region, and hospital type were recorded. A generalized linear regression model was conducted to analyze the effect of fracture type on LOS and cost.

Results:

Differences in gender (66% vs 83.7% female, P < .01), comorbidities (fewer in hips, P < .01), and costs (US$30 979 vs US$27 944, P < .01) were found between the hip and knee groups. Knees had significantly higher rates of ORIF treatment (80.7% vs 39.1%) and lower rates of revision arthroplasties (19.3% vs 60.9%) than hip PPFXs (P < .01). Within both groups, patients with more comorbidities, revision surgery, and blood transfusions were more likely to have a longer LOS and higher cost.

Conclusion:

Periprosthetic femur fractures patients are not homogenous and treatment varies between hip and knee locations. For knee patients, those treated with ORIF were younger, with fewer comorbidities than those treated with revision. Conversely, hip patients treated with ORIF were older, with more comorbidities than those treated with revision. Hips had higher costs than knees, and cost correlated with revision arthroplasty and more comorbidities. In both hip and knee groups, longer LOS was associated with more comorbidities and being treated in urban teaching hospitals. Total cost had the strongest associations with revision procedures as well as number of comorbidities and blood product use.

Acute Distal Femoral Replacement for Fractures About the Knee in the Elderly

Distal femoral replacement (DFR) is a reasonable treatment option when used for select indications. In the setting of comminuted intra-articular distal femoral fractures, distal femoral arthroplasty should be considered in low-demand patients with poor bone quality. This article summarizes the existing literature plus the authors' personal experience with DFR use for distal femoral fractures of the native knee.

Total knee arthroplasty with distal femoral replacement is associated with an important complication rate. A case series

BACKGROUND

With the aging population and an increasing number of total knee arthroplasties (TKAs) performed yearly worldwide, revision surgeries for many causes (septic or aseptic loosening, periprosthetic femoral fractures (PDFF), non-unions, malunions) are more frequent and challenging. Distal femoral replacement (DFR) is sometimes the only option to restore knee function and quality of life. DFR in non-oncologic patient is still a rare indication and few reports are published on this topic, with a non-consistent variety of functional results, complication rates and survivorship.

METHODS

We present a retrospective series of patients who underwent a DFR for a non-oncologic indication between 2010 and 2017. Nineteen patients were available for a full evaluation (clinical and radiological) with a mean follow-up of 48.3 months (range 15-99). Goniometry was performed at the six-week postoperative visit. Complications were reported. Osteolysis and/or signs of aseptic loosening were described using the Knee Society Radiographic Evaluation. Survivorship was calculated for aseptic loosening, infection, and revision for any cause.

RESULTS

The mean Knee Society Score was good for the pain score (42.2, range 10-50) and fair for the function score (60.6, range 0-100). Four deep infections (21.1%) were successfully treated with mobile parts exchange and debridement. Three patients presented femoral osteolysis ≥5 years after the DFR. Survivorship for aseptic loosening was 100% at four years, 81.8% after five years and 53.3% after eight years.

CONCLUSIONS

TKA with DFR is a valuable option for patients with a severe bone loss and poor bone quality in the distal femur. DFR restores an acceptable quality of life but is related to an important complication rate.

Single-stage bilateral distal femur replacement for traumatic distal femur fractures

Treatment of periprosthetic distal femur fractures and comminuted intraarticular distal femur fractures with previous arthritis remains a difficult challenge for orthopedic surgeons. Previous case series have shown that distal femur replacement (DFR) can effectively compensate for bone loss, relieve knee pain, and allow for early ambulation in both of these fracture patterns. Owing to the typical low-energy mechanism of these injuries, a bilateral injury treated with DFR is rarely encountered. We present a patient with traumatic open left Rorabeck III/Su III periprosthetic distal femur fracture and closed right intraarticular distal femur fracture (AO fcation 33-C2) with end-stage arthrosis treated with single-stage bilateral DFR. We suggest that in patients with similar injuries, single-stage bilateral DFR can provide the benefits of early mobilization and accelerated recovery.

Equivalent mortality and complication rates following periprosthetic distal femur fractures managed with either lateral locked plating or a distal femoral replacement

INTRODUCTION

Management of distal femur fractures above total knee arthroplasty (TKA) remains challenging. Two common surgical options are locked lateral plating (LLP) and distal femoral arthroplasty (DFR). Unfortunately, approximately 30-50% of patients may die within one year of injury, require further surgery, or not regain prior mobility performance. We compared 87 LLP to 53 DFR patients - to our knowledge the largest comparative study - focusing on 90- and 365-day mortality, mobility maintenance, and further surgery.

METHODS

We performed a retrospective review of patients at least 55 years old who sustained femur fractures near a primary TKA (essentially OTA-33 or Su types 1, 2, or 3) from 2000 to 2015 assigning cohort based on treatment: LLP or DFR. We excluded patients having prior care for the injury, whose surgery was not for fracture (e.g. loosening), or having other surgical intervention (e.g. intramedullary nail).

RESULTS

Results Cohorts were similar based on body mass index and age adjusted Charlson Comorbidity Index (aaCCI). LLP was more common than DFR for fractures above and at the level of the implant, but similar for fractures within the implant for patients with aaCCI ≥ 5. LLP and DFR had similar mortality at 90 days (9% vs 4%) and 365 days (22% vs 10%), need for additional surgery (9% vs 3%), and survivors maintaining ambulation (77% vs 81%). Patients whose surgery occurred 3 or more days after presentation had similar mortality risk to those whose surgery was before 3days. The mean age of one year survivors was 77 whereas for patients who died it was 85. Neither surgical choice nor aaCCI was associated with increased risk in time to surgery.

CONCLUSIONS

Fracture location, remaining bone stock, and patient's prior mobility and current comorbidities must guide treatment. Our study suggests that 90- and 365-day mortality, final mobility, and re-operation rate are not statistically different with LLP vs DFR management.