Distal femur fractures in elderly treated with internal fixation or distal femoral replacement - retrospective cohort study on 75 patients assessing functional outcomes, reoperations, and mortality.

PURPOSE: This cohort study aimed to describe the functional outcomes, complications, and mortality of patients over 65 with acute distal femur fractures treated with open reduction and internal fixation (ORIF) or distal femoral replacement (DFR). METHODS: We retrospectively analyzed all patients older than 65, operated consecutively for a distal femur fracture treated with ORIF or DFR. We included 75 patients (9 33A, 5 33B, and 61 33C AO/OTA fractures), 55 treated with ORIF, and 20 with DFR. We used Parker's mobility index (PMI) to assess functional outcomes at 1, 3, and 12 months and study closure. We analyzed complications, reoperations, and mortality at 30 days, one year, and at the end of the study. RESULTS: The PMI was significantly higher in the DFR group at months 1 (p = 0.023) and 3 (p = 0.032). We found no significant differences between cohorts at one year and the end of follow-up. Postoperative complications were significantly more frequent in the ORIF group (38.10% vs. 10%, p = 0.022). Reoperations were similar in both cohorts (p = 0.98). Mortality at one month was 4% and 20% at one year, and at the end of follow-up, there were no significant differences between groups. CONCLUSION: The outcomes of this study suggest that DFR offers a faster functional recovery with lower complication rates than those treated with ORIF. Additionally, both options have similar reoperation and mortality rates. Appropriately designed studies are needed to define the best treatment strategy for this type of patient.

High revision rates and mortality after distal femoral replacement for periprosthetic distal femoral fractures: analysis from the German Arthroplasty Registry (EPRD).

PURPOSE: This study was initiated to analyze the outcome after distal femoral replacement (DFR) for periprosthetic distal femoral fractures (PDFF). METHODS: Data from the German Arthroplasty Registry (EPRD) were analyzed. A total of 626 patients could be identified with a DFR for PDFF. Mean age was 78.8 years, and 84.2% were female. Revisions and mortality were analyzed and compared with patient groups with a similar procedure (revision total knee arthroplasty) or similar general condition (fracture total hip arthroplasty, hip hemiarthroplasty). Matched-pair-analyses were performed. RESULTS: Within one year after surgery, 13.2% of the patients had died and further 9.4% were revised. Within four years, 32.7% had died and 19.7% were revised. Revisions were nearly twice as high as in the comparison groups. Periprosthetic infection (PJI) was the most frequent cause for revision, resulting in a PJI rate of 12.8%, which was lower in the comparison groups. Mortality after DFR was as similar high as after fracture hip arthroplasty. CONCLUSION: PDFF are a serious injury, and the necessary surgical treatment has a high risk of complications. Every third patient after DFR for PDFF had died and every fifth patient needed revision within 4 years after surgery. Efforts should be undertaken to provide optimal treatment to these high-risk patients to reduce unfavorable outcomes. LEVEL OF EVIDENCE: III. REGISTRATION OF CLINICAL TRIALS: As this is a registry-derived study of data of the German Arthroplasty Registry (EPRD), no registration was performed.

Osseointegration reduces aseptic loosening of primary distal femoral implants in pediatric and adolescent osteosarcoma patients: a retrospective clinical and radiographic study.

AIM: The challenge of distal femoral replacement (DFR) longevity remains a priority for orthopaedic oncologists as the overall survival and activity level of young patients with osteosarcoma continues to improve. This study hypothesized that increased extracortical osseointegration at the bone-implant shoulder (i.e., where the metal implant shaft abuts the femur) will improve stress transfer adjacent to the implant, as evidenced by reduced cortical bone loss, radiolucent line progression and implant failure in young patients (< 20 years) following DFR surgery. METHODS: Twenty-nine patients of mean age 13.09 ± 0.56 years received a primary DFR. The clinical outcome of 11 CPS®, 10 GMRS®, 5 Stanmore® and 3 Repiphysis® implants was evaluated over a mean follow-up period of 4.25 ± 0.55 years. The osseous response to a bone-implant shoulder composed of either a hydroxyapatite-coated grooved ingrowth collar (Stanmore®), a porous metal coating (GMRS®) or a polished metal surface (Repiphysis®) was quantified radiographically. RESULTS: All (100.0%) of the Stanmore® implants, 90.0% of GMRS®, 81.8% of CPS® and 33.3% of the Repiphysis® implants survived. Significantly increased extracortical bone and osseointegration were measured adjacent to the Stanmore® bone-implant shoulder when compared with the GMRS® and Repiphysis® implants (p < 0.0001 in both cases). Significantly decreased cortical loss was identified in the Stanmore® group (p = 0.005, GMRS® and p < 0.0001, Repiphysis®) and at 3 years, the progression of radiolucent lines adjacent to the intramedullarly stem was reduced when compared with the GMRS® and Repiphysis® implants (p = 0.012 and 0.026, respectively). CONCLUSIONS: Implants designed to augment osseointegration at the bone-implant shoulder may be critical in reducing short- (≤ 2 years) to mid- (≤ 5 years) term aseptic loosening in this vulnerable DFR patient group. Further longer-term studies are required to confirm these preliminary findings.

Patient safety in distal femoral resection knee arthroplasty for non-tumor indications: a single-center consecutive cohort study of 45 patients.

BACKGROUND: Distal femoral resection knee arthroplasty may be a viable option for several indications other than bone tumors. Resection knee arthroplasty appears to be becoming more common, but patients requiring this type of surgery are often elderly and with high comorbidity. The aim of this study was to report in-hospital complications, readmissions, reoperations, and mortality after distal femoral resection knee arthroplasty for non-tumor indications. METHODS: We retrospectively identified a consecutive cohort of 45 knees (45 patients) treated with distal femoral resection knee arthroplasty in a single institution between 2012 and 2021. Indications for surgery were failure of osteosynthesis (8), primary fracture treatment (2), periprosthetic fracture (22), and revision arthroplasty with severe bone loss (13). A major reoperation was defined as a major component exchange procedure or amputation. Mean follow-up was 3.9 years. RESULTS: The mean age was 71.3 years (SD 12.3), and 64.4% were female; 8.9% were ASA I, 40% ASA II, and 51% ASA III. Median length of stay was 7 days (range 3-19) with no major in-hospital complications, but 55.6% (n = 25) required blood transfusion. The 90-day readmission rate was 17.8% (n = 8), of which 50% was prosthesis-related. Four patients (8.9%) underwent major reoperation due to infection (n = 2), mechanical failure (n = 1), or periprosthetic fracture (n = 1). The mortality rate was 0% ≤ 90 days and 2.2% ≤1 year. CONCLUSIONS: Distal femoral resection knee arthroplasty in this fragile patient population appears to be a viable and safe option considering that it is a limp salvage procedure most cases.

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.

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.

Distal femoral replacement versus ORIF for severely comminuted distal femur fractures.

INTRODUCTION: Distal femoral replacement (DFR) and open reduction and internal fixation (ORIF) are surgical options for comminuted distal femur fractures. Comparative outcomes of these techniques are limited. The aims of this study were to compare implant survivorship, perioperative factors, and clinical outcomes of DFR vs. ORIF for comminuted distal femur fractures. METHODS: Ten patients treated with rotating hinge DFRs for AO/OTA 33-C fractures from 2005 to 2015 were identified and matched 1:2 based on age and sex to 20 ORIF patients. Patients treated with DFR and ORIF had similar ages (80 vs. 76 years, p = 0.2) and follow-up (20 vs. 27 months, p = 1.0), respectively. Implant survivorship, length of stay (LOS), anesthetic time, estimated blood loss (EBL), ambulatory status, knee range of motion (ROM), and Knee Society scores (KSS) were assessed at final follow-up. RESULTS: Survivorship free from any revision at 2 years was 90% and 65% for the DFR and ORIF groups, respectively (p = 0.59). Survivorship free from any reoperation at 2 years was 90% for the DFR group and 50% for the ORIF group (p = 0.16). Three ORIF patients (15%) went on to nonunion and two went on to delayed union. Mean EBL and LOS were significantly higher for the DFR group: 592 mL vs. 364 mL, and 13 vs. 6.5 days, respectively. Knee ROM (p = 0.71) and KSSs (p = 0.36) were similar between groups. CONCLUSIONS: Comminuted distal femur fractures treated with DFR trended toward lower revision and reoperation rates, with similar functional outcomes when compared to ORIF. We noted a trend toward increased EBL and LOS in the DFR group. LEVEL OF EVIDENCE: Level IV.

Comparison of all-polyethylene and metal-backed modular tibial components in endoprosthetic reconstruction of the distal femur.

INTRODUCTION: All-polyethylene (AP) tibial components have demonstrated equivalent or improved long-term survivorship and reduced cost compared with metal-backed (MB) components in primary total knee arthroplasty; however, there is a lack of data comparing these outcomes in the setting of an oncologic endoprosthetic reconstruction. METHODS: A total of 115 (88 AP:27 MB) patients undergoing cemented distal femur endoprosthetic reconstruction following oncologic resection were reviewed. Mean age was 40 years and 51% were females. Cumulative incidences of all-cause revision, tibial component revision, reoperation, and infection were calculated utilizing a competing risk analysis with death as the competitor. Mean follow-up was 14 years. RESULTS: The 10-year cumulative incidence of all-cause revision was 19.9% in the AP group and 16.3% in the MB group (hazard ratio [HR] = 0.93, p = 0.88). The cumulative incidence of tibial component revision was significantly lower in AP compared with MB at 10 years (1.1% vs. 12.5%, HR = 0.18, p = 0.03). There was no difference in infection-free survival when comparing the two groups (p = 0.72). CONCLUSIONS: Reconstruction utilizing an MB or AP tibia component resulted in equivalent overall outcome; however, the tibial component in the AP group was less likely to be revised. AP tibial component should be considered for all primary oncologic reconstructions in the distal femur. LEVEL OF EVIDENCE: Level III Therapeutic.

Metaphyseal Stem Tip Location is a Risk Factor for Aseptic Loosening of Cemented Distal Femoral Replacements.

BACKGROUND: The objective of this study was to describe the incidence of aseptic loosening (AL) of cemented stem distal femoral replacements (DFR) and to identify modifiable risk factors for its development. METHODS: A retrospective review was performed of 245 consecutive primary, cemented stem DFRs implanted at a single institution over a 40-year period. The primary outcome was revision surgery for AL. A multivariate analysis was performed to identify risk factors for AL. Radiographs were reviewed to identify stem tip location, which was defined as diaphyseal or metaphyseal. Implant survival to AL was compared using Kaplan-Meier analysis. RESULTS: AL and structural failure were the most common causes of implant failure (incidence 11.8%, 29/245). Younger age (P = .002), male sex (P = .01), longer resection length (P = .04), and nonmodular implants (P = .002) were all significantly associated with AL. After 1:1 matching, stem tip location in metaphyseal bone was independently associated with AL (P = .04). 36% (9/25) of implants that loosened had a stem tip located in the metaphysis vs only 8% (2/25) of implants that did not fail. 30-year survival to AL was lower for implants with a metaphyseal stem tip than implants with a diaphyseal stem tip (22.7% vs 47.6%; P = .11). CONCLUSION: A stem tip location in metaphyseal bone is associated with diminished survival to AL. When templating before DFR, stem tip location can assist in identifying high-risk reconstructions that may benefit from alternative or supplemental fixation techniques to prevent the development of AL.

Distal Femoral Replacement and Periprosthetic Joint Infection After Non-Oncological Reconstruction: A Retrospective Analysis.

BACKGROUND: Distal femoral replacement (DFR) is commonly used to manage massive bone loss around the knee arising from aseptic loosening, periprosthetic joint infection (PJI), and distal femoral fractures. A number of studies report the outcome of DFR with considerable variation in long-term survivorship. This study investigated the outcome of DFR for patients with aseptic failures, fractures, and PJI. METHODS: A retrospective review of 182 patients who underwent DFR for non-oncological indications between 2002 and 2018 was conducted. Data collected included the following: indication, postoperative complications, reoperation, revision, and follow-up. Implant survivorship with Kaplan-Meier curves along with a log-rank test for different preoperative indications was performed. A Cox regression model was used to evaluate the risk of revision. RESULTS: The overall postoperative complication rate was very high at 36%. The most common complication was PJI (17%). The rate of reoperation for any cause was 29.7%, and the revision rate was 13.7%. The most common cause of re-revision was PJI (7.1%). Revision-free survivorship of the DFR implant was 91.6% at 1 year, 87.9% at 2 years, 82.5% at 5 years, and 73.4% at 10 years. Patients who had a prior-PJI had the lowest survivorship compared to patients undergoing DFR for management of periprosthetic fracture and mechanical loosening. Additionally, the prior-PJI group was at a fourfold increased risk of postoperative PJI compared to the aseptic group. CONCLUSION: DFR is a valuable reconstructive option for patients with massive bone loss around the knee. However, patients undergoing DFR are at high risk of complications, reoperations, and failure.

Contemporary Distal Femoral Replacements for Supracondylar Femoral Fractures Around Primary and Revision Total Knee Arthroplasties.

BACKGROUND: There is a paucity of data on the outcomes of distal femoral replacements (DFRs) in patients with total knee arthroplasty (TKA) periprosthetic fractures. We sought to characterize these patients' survivorship free from rerevision. METHODS: We retrospectively identified 49 patients, including 34 after primary TKA (primary cohort), 9 after revision TKA, and 6 conversions for failed open reduction and internal fixation (revision cohort) that underwent DFR for a periprosthetic femur fracture. The mean age was 76 years, and 40 patients (82%) were female. The mean follow-up was 4 years. Femoral fixation included 44 cemented stems (90%) and 5 cementless stems (10%). Survivorship free from rerevision was characterized by the Kaplan-Meier method; cox proportional regression was used to analyze the risk factors for rerevision. RESULTS: Survivorship free from any rerevision at 5 years in the primary and revision cohort was 93% and 18%, respectively. The revision cohort had a 5.3× higher risk of re-revision (P = .008). Survivorship free from re-revision for aseptic loosening at 5 years in the primary and revision cohort was 93% and 53%, respectively. Two of the 3 patients with cementless stems in the primary cohort underwent early rerevision for aseptic loosening, but patients with prior primary TKAs treated with cemented femoral fixation (n = 31) had a 97% 5-year survivorship free from re-revision. CONCLUSION: Patients with periprosthetic fractures around prior primary TKAs treated with DFRs with cemented femoral fixation had a 97% 5-year survivorship free from any re-revision. DFRs for periprosthetic femur fractures around revision TKAs or conversions of failed open reduction and internal fixations have a 5× increased risk of rerevision.

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.

[Locking plate fixation of distal periprosthetic femoral fractures : Clinical outcome and mortality]. / Winkelstabile Plattenosteosynthese bei distalen periprothetischen Femurfrakturen : Klinisches Outcome und Mortalität.

BACKGROUND: The care of distal periprosthetic femoral fractures (PFF) is becoming a major interdisciplinary challenge due to demographic developments. The operative treatment is often performed (depending on the type of fracture) by means of locking plate fixation (LPF), although little data on the clinical outcome exist by now. The aim of the study is to identify risk factors for a poor outcome and increased mortality METHODS: In this retrospective study, 36 cases with distal PFF were examined. Exclusively treatment with LPF were included. Relevant previous illnesses (ASA score, Charlson index), fracture morphology and major complications were recorded as well as 1- and 3- year mortality. The clinical outcome was detected by using the Lysholm score. RESULTS: The 1- and 3- year mortality were 9% and 26% - exclusively affecting ASA 3 and 4 patients. The Lysholm Score showed a high variability (65 ± 27 points) with higher values in the ASA 1-2 subgroup (82 vs. 63 points) but independent of fracture type. The preoperative ASA score, the Charlson comorbidity index, and the patient age were determined to be decisive for 3-year mortality. CONCLUSION: This case series displayed a high absolute mortality even if the rate was slightly lower compared to previously published data. The rate of secondary dislocations, lack of fracture healing or follow-up operations were also low. The LPF therefore appears to be a suitable treatment for fractures with a stable prosthesis. However, there is a high variability in the clinical outcome regardless of the type of fracture and significantly increased mortality rates in previously ill patients.

Periprosthetic Fractures of the Distal Femur: Is Open Reduction and Internal Fixation or Distal Femoral Replacement Superior?

BACKGROUND: The purpose of this study is to compare open reduction and internal fixation (ORIF) to distal femoral replacement (DFR) for treatment of displaced periprosthetic distal femur fractures. METHODS: We identified 72 patients with minimum 2-year follow-up following a displaced periprosthetic distal femur fracture: 50 were treated with ORIF and 22 with DFR. Outcomes were assessed with multivariate regression analysis and include Knee Society Scores (KSS), infection rates, revision incidence, and mortality. RESULTS: Patients treated with DFR had a higher Charlson comorbidity index (5.2 vs 3.8; P = .006). The mean postoperative KSS were similar between groups, but the Knee Society Functional Scores were higher in the ORIF group (P = .01). Six ORIF patients (12%) and 3 DFR patients (14%) underwent a revision surgery (P = .1). In the ORIF group, 3 revisions were associated with periprosthetic infection, and 3 revisions occurred for aseptic nonunion. In the DFR group, 1 infection was treated with irrigation and debridement, and 2 cases of patellar maltracking resulted in 1 liner exchange with soft tissue release and 1 femoral revision for malrotation. More patients in the ORIF group required repeat revisions, with twice as many total revisions (P < .001). Six ORIF patients and 7 DFR patients died within 2 years (P = .26). CONCLUSION: The Knee Society Functional Score favored ORIF, but the total incidence of revision was higher in the ORIF cohort. Given the high mortality and the substantial risk of reoperation in both groups, additional studies are needed regarding the prevention of and optimal treatment for patients with periprosthetic distal femur fractures.

Comparison between uncemented and cemented fixation for the tibial component in distal femoral replacement: a clinical and radiological study.

PURPOSES: We performed a retrospective, cohort study to compare uncemented tibial fixation with cemented tibial fixation in distal femoral replacement (DFR). METHODS: Sixty-two cases with uncemented tibial fixation and 58 cases with cemented tibial fixation were included. Inter-group comparisons were performed for baseline data, oncological and prosthetic outcomes, and changes of cortical thickness of tibial diaphysis. Radiological signs of bone adaptations around the uncemented tibial stem were identified through evaluation of plain films during follow-up. RESULTS: Uncemented tibial fixation shortened operative duration by 26 minutes, achieved equivalent oncological and prosthetic outcomes, and helped preserve anterior cortical thickness of tibia compared with the cemented counterpart after a mean follow-up of over 40 months. Radiological signs of osseointegration and reactive line were observed in 64.3 and 17.9% cases with uncemented tibial fixation. The two signs had different patterns of distribution and no significant predisposing factors could be identified. CONCLUSIONS: For DFR, the uncemented tibial fixation was safe and effective in functional reconstruction and in preservation of anterior cortex of tibial diaphysis. It could achieve osseointegration and might permit adaptive micromotion of the tibial stem post-operatively. LEVEL OF EVIDENCE: level III Therapeutic.

Revision knee arthroplasty using a distal femoral replacement prosthesis for periprosthetic fractures in elderly patients.

PURPOSE: Distal femoral periprosthetic fractures above a total knee replacement in elderly patients are technically challenging to treat. Bone quality is often poor, the fractures comminuted, and post-operative mobilisation is difficult. This study assesses the clinical, radiological and functional outcome of revision knee distal femoral replacement (DFR) in these fractures. METHODS: We identified 14 patients over 70 years of age (70-94) who underwent DFR for periprosthetic fractures above a knee replacement. All the 14 fractures were classified as Su type III. Clinical and radiological records were retrospectively reviewed. The mean of clinical follow-up was 27 months (8-46). Functional outcome was assessed using Oxford Knee Score and EQ-5D (UK English Version) score at a mean time of 35 months (20-65). The Knee Society patient category score was also evaluated. RESULTS: The median post-operative knee flexion was 100° (range 90°-135°). Nine patients (64%) returned to their pre-fracture level of mobility or better. The median post-operative Oxford Knee Score was 27 (range 4-40). The median EQ-5D was 11 (range 6-12). Cognitive impairment negatively impacted the functional outcome in four patients. One patient died early post-operatively, and two patients had complications. CONCLUSIONS: DFR led to satisfactory outcome in our patients with a relatively low complication rate. In our experience, revision knee distal femoral replacement is an appropriate method to treat elderly patients who sustained periprosthetic Su et al. type III distal femoral fractures in association with poor bone stock, caused by osteoporosis and/or comminution.

Distal femoral replacement with the MML system: a single center experience with an average follow-up of 86 months.

BACKGROUND: The aim of this study was to compare the functional outcomes and complication rates after distal femoral replacement (DFR) performed with the modular Munich-Luebeck (MML) modular prosthesis (ESKA/Orthodynamics, Luebeck, Germany) in patients being treated for malignant disease or failed total knee arthroplasty. METHODS: A retrospective review of patient charts and a functional investigation (involving Musculoskeletal Tumor Society Score [MSTS], American Knee Society Score [AKSS], Oxford Knee Score [OKS], Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], Toronto Extremity Salvage Score [TESS], the 12-Item Short-Form [SF-12] Health Survey, and a failure classification system developed by Henderson et al.) of DFR cases from 2002 to 2015 were conducted. The indications for DFR were malignant tumor resection in the femur (n = 20, group A) or failure of revision total knee arthroplasty without a history of malignant disease (n = 16, group B). RESULTS: One-hundred and twenty-nine patients were treated during the study period. Of these, 82 were analyzed for complications and implant-survival. Further, 36 patients were available for functional assessment after a mean follow-up of 86 months (range: 24-154). There were 75 complications in total. The overall failure rate for DFR was 64.6% (53/82 patients). The most common failure mechanisms were type III (mechanical failure), followed by type I (soft tissue) and type II (aseptic loosening). The mean MSTS score (out of 30) was 17 for group A and 12 for group B. All the clinical outcome scores revealed an age-dependent deterioration of function. CONCLUSION: DFR is an established procedure to restore distal femoral integrity. However, complication rates are high. Post-procedure functionality depends mainly on the patient's age at initial reconstruction.

Predictors of Functional Recovery Following Periprosthetic Distal Femur Fractures.

BACKGROUND: Treatment options for periprosthetic distal femur fractures include open reduction internal fixation (ORIF) and distal femoral replacement (DFR). The purpose of this study was to evaluate the complications, and functional recovery (ambulatory status, living situation, mortality) in patients undergoing operative treatment (DFR and ORIF) of periprosthetic distal femur fractures. METHODS: A retrospective review of 58 patients with distal femoral periprosthetic fractures treated with either ORIF or DFR was conducted. Surgical complications, discharge disposition, ambulatory status, living situation at 1 year, and mortality at 1 year were compared between patients treated with ORIF and DFR. Outcomes at 1 year were also compared between patients older and younger than 85 years of age. RESULTS: Fifty-eight patients with a mean age of 80 years (range, 61-95 years) met inclusion criteria. The mean follow-up was 29.5 months (range, 5-81 months). Patients undergoing DFR were significantly older than those who underwent ORIF (83 vs 78, P < .01). The 1-year mortality rate was 20.6%. There was no difference between groups with respect to mortality, complications, discharge disposition, or ambulatory status and living situation at 1 year. Patients who lost the ability to ambulate at 1 year were significantly older than patients who maintained the ability to ambulate (87.5 vs 76.4 years, P < .05). Patients older than 85 years were more likely to lose the ability to ambulate and to live in a skilled nursing facility at 1 year (P < .01). CONCLUSION: Distal femoral periprosthetic fractures have a high morbidity and mortality. Age at time of injury, not treatment rendered, is predictive of ambulatory status and living independence after periprosthetic distal femur fractures.

Open Reduction vs Distal Femoral Replacement Arthroplasty for Comminuted Distal Femur Fractures in the Patients 70 Years and Older.

BACKGROUND: The ideal management of distal femur fractures in the elderly is unclear. Acute arthroplasty has the theoretical advantage of earlier mobilization. We examined the outcomes of patients 70 years and older who underwent open reduction internal fixation (ORIF) vs distal femoral replacement (DFR) for comminuted, intra-articular distal femur fractures. METHODS: A retrospective review of patients with AO/OTA classification 33C distal femur fractures treated with either ORIF or DFR was performed. Outcomes including all-cause reoperation, length of stay, fracture union, postoperative complications, use of ambulatory device and living situation at 1 year, and mortality were evaluated. RESULTS: The study cohort included 38 patients: 10 underwent DFR and 28 ORIF. Mean patient age for both cohorts was 82 years. No difference in comorbidities or mechanism of injury was found between groups. The incidence of reoperation was 11% in the ORIF group and 10% in the DFR group. In the ORIF group, the average time to fracture union was 24 weeks, with a nonunion incidence of 18%. Twenty-three percent of ORIF group were wheelchair dependent vs none in the DFR cohort, although not statistically significant. Differences between the groups with respect to all-cause reoperation, living situation or need for ambulatory device at 1 year, and 1-year mortality did not reach statistical significance. CONCLUSION: Nearly 1 in 5 patients older than 70 years developed a nonunion after ORIF of an intra-articular distal femur fracture. At 1-year follow-up, all patients in DFR group were ambulatory while 1 in 4 in the ORIF group were wheelchair bound.

Distal femoral replacement for the treatment of periprosthetic distal femoral fractures around a total knee arthroplasty: a meta-analysis.

Background: Periprosthetic fracture is a rare complication of arthroplasty but can have devastating consequences for the patient and presents a complex surgical challenge. Locking compression plate and retrograde intramedullary nail are both widely accepted surgical fixation techniques for distal femoral periprosthetic fractures around a total knee arthroplasty. Although there is still a need for further high-quality research into both techniques, there is even less literature concerning the use of distal femoral replacement to treat distal femoral periprosthetic fractures. Interest has been piqued in distal femoral replacements for the treatment of distal femoral periprosthetic fractures due to the theoretical advantages of immediate post-operative weight-bearing and lack of dependence on fracture union, but there are still understandably reservations about performing such an extensive and invasive procedure when an accepted alternative is available. This meta-analysis aims to evaluate the current literature to compare the complication rates and return to pre-operative ambulatory status of distal femoral replacement and locking compression plate. Method: A literature search was performed to identify articles related to the management of distal femoral periprosthetic fractures around a total knee arthroplasty in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Methodological quality was assessed using the methodological index for non-randomized studies (MINORS) criteria. Articles were reviewed, and data extracted for analysis. Results: Five articles met the inclusion criteria, reporting on 345 periprosthetic fractures. The overall rates of complications for distal femoral replacement and locking compression plate were: re-operation (6.1% vs 12.1%), infection (3.0% vs 5.3%), mortality (19.7% vs 19.3%), and return to pre-operative ambulatory status (60.9% vs 71.8%) (respectively). Conclusion: This meta-analysis shows no statistically significant difference in the rates of re-operation, infection, mortality or return to pre-operative ambulatory status when comparing distal femoral replacement to locking compression plate.