Treatment Options for Distal Femur Fractures

Outcomes of operatively managed periprosthetic distal femur fractures compared to fractures in patients with native knees

Introduction

With the increasing incidence of total knee arthroplasty (TKA), there is an expected rise in rate of periprosthetic fractures in the coming years. It is unclear how the outcomes of patients with distal femur fractures (DFF) and a total knee arthroplasty compare to patients of the same age group with native knees (NK).

Materials and methods

A retrospective review was completed for distal femur fractures treated with surgical fixation from January 2019-March 2021. We excluded patients <50 years old, non-ambulatory patients, revision surgeries, and patients with less than 90 days of follow-up. A chart review was performed to collect age, gender, BMI, smoking status, American Society of Anesthesiology (ASA) classification, fracture type, fixation method, time to full weight bearing, and complications. Comparisons between the TKA vs native knee groups were performed using t-test, chi-square, and Fisher's exact test where appropriate.

Results

138 patients were included in our study with a mean age of 74 years. 69 DFF ipsilateral to a TKA were included in the study group and 71 DFF were included in the native knee group. Age, sex, BMI, smoking status, and ASA class were similar between the groups. All patients with periprosthetic femur fractures had 33A AO/OTA fracture classification. Patients with native knees were more likely to receive dual implant fixation, 15.5% compared to 4.3% (p = 0.02). Full weight bearing was achieved at 8.5 vs 8.6 weeks between the NK and TKA groups (p = 0.64). The complication rate was 16.9% in the NK group vs. 7.2% in the TKA group (p = 0.21).

Conclusion

Patients with periprosthetic femur fractures have similar time to weight bearing and complications rate with patients with distal femur fracture in native knees. We found a higher utilization rate of dual implant fixation in the native knee group.

Which fixation produces the best outcome for distal femoral fractures? Meta-analysis and systematic review of retrograde nailing versus distal femoral plating in 2432 patients and 33 studies

PURPOSE

The distal femur comprises a wide intramedullary cavity and thin cortical bone. Firm internal fixation of comminuted fractures with displacement is challenging. Although many comparative studies have reported retrograde intramedullary nailing (RIN) and distal femoral plating (DFP) as the usual fixation methods for distal femoral fractures, no clear conclusion has been reached. Therefore, a meta-analysis and systematic review of the clinical and radiological results were conducted to determine the appropriate treatment method for distal femoral fractures.

METHODS

A systematic search of the PubMed, Embase, Scopus, and Cochrane Library databases from their inception to December 19, 2022, was performed using predefined criteria. Studies comparing the effects of RIN and DFP were considered. The analyzed outcome measures included duration of surgery, blood loss, time to union, delayed union, nonunion, malalignment, implant failure, infection, reoperation, limb length discrepancy, range of motion, persistent anterior knee pain, knee stiffness, and functional scores. Meta-analysis of pooled data was conducted using a random-effects model to determine the standard mean difference (SMD) or odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

Thirty-three studies with 2,432 patients were included. Compared to DFP, RIN was associated with a shorter time to fracture union (SMD, 1.83 months; 95% CI - 2.76 to - 0.90; P < 0.001) and a lower incidence of postoperative infection (OR 0.54; 95% CI 0.31-0.94; P = 0.03). Pooled analysis revealed no significant differences in other outcome measures between the two treatment modalities.

CONCLUSION

In distal femoral fractures, RIN had a shorter bone union time and was more resistant to infection than DFP. However, there were no significant differences in the other clinical parameters. Therefore, the characteristics, strengths, and weaknesses of RIN and DFP should be carefully identified, and appropriate treatment should be provided based on the patient's medical condition and fracture pattern.

Rates of interlock screw back-out are high with the retrograde femoral nailing advanced system for distal femur fractures

PURPOSE

The retrograde femoral nailing advanced (RFNA) system (DePuy synthes) is a commonly used implant for the fixation of low distal femur and periprosthetic fractures. There is concern that the rate of distal interlock screw back-out may be higher for the RFNA compared to other nails (ON). The purpose of this study was to evaluate the incidence of interlock screw back-out and associated screw removal for RFNA versus ON, along with associated risk factors.

METHODS

A retrospective comparative study of patients who underwent retrograde nailing for a distal femur fracture at an academic level one trauma center was performed. The incidence of distal interlock screw back-out and need for screw removal were compared for RFNA versus a propensity score matched cohort who received other nails.

RESULTS

One hundred and ten patients underwent retrograde nailing with the RFNA for a distal femur fracture from 2015 to 2022 (average age: 66, BMI: 32, 52.7% smokers, 54.5% female, 61.8%). There was a significantly higher rate of interlock back-out in the RFNA group compared to the ON (27 patients, 24.5% vs 12 patients, 10.9%, p = 0.01), which occurred 6.3 weeks postoperatively. Screw removal rates for back-out were not significantly different for the RFNA group versus ON (8 patients, 7.3% vs 3 patients, 2.7%, p = 0.12).

CONCLUSION

In this retrospective comparative study of distal femur fractures treated with retrograde nailing, the RFNA implant was associated with an increased risk of distal interlock screw back-out compared to other nails.

Comparative study of retrograde intramedullary nailing versus locking extramedullary plating in complete articular fractures with metaphyseal comminution of the distal femur

INTRODUCTION

Fractures of the distal femur with metaphyseal comminution and complete intra-articular involvement (AO/OTA classifications 33C2 and 33C3) present challenges for reduction and fixation. However, an optimal fixation method remains unknown. This study aimed to compare the clinical and radiographic outcomes of locking extramedullary plating (LEP) and retrograde intramedullary nailing (RIN) for complete distal femoral intra-articular fractures with metaphyseal comminution.

MATERIALS AND METHODS

Between January 2016 and May 2022, 80 patients (45 men and 35 women; average age, 56.7 years) diagnosed with AO/OTA 33C2 and 33C3 were treated with either LEP or RIN and followed up for at least one year. Post-operative evaluations included radiographic assessments of bone union rate, timing, and alignment. Clinically, the knee joint range of motion (ROM), lower extremity functional scale (LEFS), and Kellgren and Lawrence (KL) grade were analyzed. The complications were also compared.

RESULTS

36 underwent LEP and 44 underwent RIN. Bone union was observed in 69.4% and 63.6% of the patients in the LEP and RIN groups, respectively (p = 0.64). The average union time was 6.9 months for the LEP group and 6.6 months for the RIN group (p = 0.51). A tendency toward varus deformity was observed in the RIN group, although the difference was not statistically significant. No significant differences were observed in knee ROM, LEFS, or KL grade. Complications included non-union (33.8%; RIN, 11; LEP, 16), varus deformity (5%; RIN, 4; LEP, 0), infection (1.3%; RIN, 0; LEP, 1), heterotrophic ossification (1.3%; RIN, 0; LEP, 1), and wound dehiscence (2.5%; RIN, 2; LEP, 0).

CONCLUSIONS

The surgical fixation methods, RIN and LEP, for complete distal femoral intra-articular fractures with metaphyseal comminution showed similar clinical and radiological outcomes. However, regardless of the type of fixation device used, there was a reduced rate of bone union owing to high energy and a less favorable prognosis.

Retrograde intramedullary nailing with supplemental plate and lag screws allows early weight bearing following distal end-segment femur fractures (AO/OTA 33) in a low-resource setting

PURPOSE

To underline the feasibility of achieving early weight bearing in patients with distal end-segment femur fractures (AO/OTA 33) treated with retrograde intramedullary nailing and supplemental plate or lag screws in the absence of C-arm.

METHODS

41 distal end-segment femur fractures (DFFs) included in the study were treated with SIGN nails with or without a side plate in a center that lacked intraoperative fluoroscopy and fracture table. A medial or lateral para-patellar incision was used for fracture reduction, nail insertion and side plate placement. Follow-ups were done at six weeks, 12 weeks, and six months post-operatively.

RESULTS

Distal end-segment fractures constituted 13.2% of all femur fractures treated. The patients' mean age and range were 49.6 and 23-83 years respectively. They were mostly injured in road traffic accidents. 27 were daily-income earners. By the 12th week post-operatively, 82.1% of them could flex their knee beyond 90°, all of them could bear weight fully, and 71.8% could squat & smile.

CONCLUSION

The study highlighted the procedure for retrograde nailing of DFFs in a setting without the requisite facilities for minimally-invasive surgeries. The findings demonstrated the feasibility of achieving an expedited weight bearing for the predominantly daily-income-earning victims to ensure early return to work and poverty reduction. While the small sample size is a limitation, the study does provide information that could serve as a basis for future randomized controlled trials in low-resource settings.

Physical Rehabilitation Subsequent to Fixation of Ilizarov Ring Fixator for the Management of Distal Femur Fracture: A Case Report

Distal femur fractures are severe all over the world. The goal of the study was to assess the effect of physiotherapy on ROM, strength, and improving quality of life. Due to the anatomy of distal femur fracture, the Ilizarov ring fixator is useful as it helps maintain mobility and stability. Distal femur fractures are most treated surgically compared to non-surgical treatment. The use of external fixators differs according to the patient's condition and the stability of the patient. This study's objective was to evaluate the effectiveness of an evidence-based procedure prepared for the management of distal femur fracture and chronic osteomyelitis femur. In some cases, due to discharging sinus, the patient requires long-term treatment followed by a home physiotherapy rehabilitation program. The objective was to assess the effects of Ilizarov circular external fixators (ICEF) on distal femur fracture.

Management of distal femoral fractures with metaphyseal and articular comminution (AO/OTA 33C) using nail and plate fixation: a technical note and case series of 14 patients

PURPOSE

To describe the surgical technique and the outcome of a case series of comminuted intra-articular distal femur fractures (AO/OTA 33C) treated with a nail-plate combination (NPC) implant.

METHODS

We retrospectively analyzed a case series of 14 patients with comminuted intra-articular distal femur fractures (DFF) treated with an intramedullary retrograde nail in combination with a lateral low-contact condylar locking plate, in a period between June 2020 and January 2023 at a Level 1 trauma center. Baseline demographic and clinical data were recorded. Time to bone healing, function using Schatzker Lambert Score, and complications were documented.

RESULTS

Fourteen patients, 8 males and 6 females, with a total of 15 NPC implants, were included in this study. Eight out of 14 patients had open fractures, all with a Gustilo Anderson type IIIA exposure. The mean age was 48.5 ± 18.05 years. The median follow-up was 392 days, with only one patient lost to follow-up. 11 out of 15 implants achieved complete radiographic consolidation during follow-up, at a mean of 5.40 ± 1.07 months. At the 12-month follow-up, all patients could fully bear weight painlessly or with mild pain. Schatzker Lambert Score was excellent for 4 patients, good for 2 patients, fair for 5 patients, and failure for 2 patients. The main postoperative complications were rigidity (3 cases), limb shortening (2 cases), and septic non-union (1 case).

CONCLUSION

This study suggests that the nail-plate combination (NPC) may provide a more effective surgical technique for addressing the challenges associated with comminuted intra-articular distal femur fractures (AO/OTA 33C).

LEVEL OF EVIDENCE: 4

An analytical model of lateral condylar plate working length

BACKGROUND

The locking plate is a common device to treat distal femur fractures. Healing is affected by construct stiffness, thus many surgeon-controlled variables such as working length have been examined for their effects on strain at the fracture. No convenient analytical model which aids surgeons in determining working length has yet been described. We propose an analytical model and compare it to finite element analysis and cadaveric biomechanical testing.

METHODS

First, an analytical model based on a cantilever beam equation was derived. Next, a finite element model was developed based on a CT scan of a "fresh-frozen" cadaveric femur. Third, biomechanical testing in single-leg stance loading was performed on the cadaver. In all methods, strain at the fracture was recorded. An ANCOVA test was conducted to compare the strains.

FINDINGS

In all models, as the working length increased so did strain. For strain at the fracture, the shortest working length (35 mm) had a strain of 8% in the analytical model, 9% in the finite element model, and 7% for the cadaver. The longest working length (140 mm) demonstrated strain of 15% in the analytical model, and the finite element and biomechanical tests both demonstrated strain of 14%.

INTERPRETATION

The strain predicted by the analytical model was consistent with the strain observed in both the finite element and biomechanical models. As demonstrated in existing literature, increasing the working length increases strain at the fracture site. Additional work is required to refine and establish validity and reliability of the analytical model.

Effect of Physiotherapy on a Rare Case of Malunion of Femur and Patellar Fracture in a 43-Year-Old Male: A Case Report

The hip is a ball-and-socket joint surrounded by strong and well-balanced muscles that allow for a wide range of motion in many physical planes. Iliofemoral, ischiofemoral, and pubofemoral are the three major ligaments of the hip joint that provide stability to the joint. Supracondylar femoral fractures are common in old age and can be caused in young people due to accidents or traumatic causes. These types of fractures are complicated to fix surgically due to different architectural designs. If not treated appropriately, these can cause malunion or non-union of the joint. The knee joint is a synovial joint of the hinge type. It has two major degrees of movement, which are flexion and extension. However, rotation in both the medial and lateral directions is possible to some extent in the joint. Patellar fractures can be transverse, vertical, comminuted, marginal, or osteochondral. In this case report, we present a 43-year-old male patient who had a history of falling from a bike. He was diagnosed with a comminuted supracondylar fracture of the left femur and a comminuted fracture of the patella on the left side on an X-ray. For this, he was managed with open reduction, internal fixation, and vacuum-assisted closure (VAC). Physiotherapy rehabilitation was programmed to attain a good and fast recovery for the patient to make him functionally independent and improve his quality of life.

Risk Factors for Nonunion of Distal Femur Fractures

OBJECTIVES

To determine patient, fracture, and construct related risk factors associated with nonunion of distal femur fractures.

DESIGN

Retrospective cohort study.

SETTING

Academic Level I trauma center.

PARTICIPANTS

Patients 18 years and older presenting with OTA/AO 33A and 33C distal femur fractures from 2004 to 2020. A minimum follow-up of 6 months was required for inclusion. OTA/AO 33B and periprosthetic fractures were excluded, 438 patients met inclusion criteria for the study.

MAIN OUTCOMES

The primary outcome of the study was fracture nonunion defined as a return to the OR for management of inadequate bony healing. Patient demographics, comorbidities, injury characteristics, fixation type, and construct variables were assessed for association with distal femur fracture nonunion. Secondary outcomes include conversion to total knee arthroplasty, surgical site infection, and other reoperation.

RESULTS

The overall nonunion rate was 13.8% (61/438). The nonunion group was compared directly with the fracture union group for statistical analysis. There were no differences in age, sex, mechanism of injury, Injury Severity Score, and time to surgery between the groups. Lateral locked plating characteristics including length of plate, plate metallurgy, screw density, and working length were not significantly different between groups. Increased body mass index [odds ratio (OR), 1.05], chronic anemia (OR, 5.4), open fracture (OR, 3.74), and segmental bone loss (OR, 2.99) were independently associated with nonunion. Conversion to total knee arthroplasty (TKA) ( P = 0.005) and surgical site infection ( P < 0001) were significantly more common in the nonunion group.

CONCLUSION

Segmental bone loss, open fractures, chronic anemia, and increasing body mass index are significant risk factors in the occurrence of distal femoral nonunion. Lateral locked plating characteristics did not seem to affect nonunion rates. Further investigation into the prevention of nonunion should focus on fracture fixation constructs and infection prevention.

LEVEL OF EVIDENCE

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

5-year fracture risk among children with cerebral palsy

BACKGROUND

Epidemiologic evidence documenting fracture risk as children with cerebral palsy (CP) age throughout growth is lacking to inform on when to implement fracture prevention strategies. The objective was to characterize the 5-year risk of fractures by each year of age among <1-13 year olds with CP and effects by patient-level factors.

METHODS

This retrospective cohort study used commercial administrative claims from 01/01/2001 to 12/31/2018 from children <1-13 years old with ≥5 years of insurance enrollment. Fractures were examined during the 5-year follow-up. For the CP cohort, the association between 5-year fracture rate and patient-level factors was assessed using Cox regression.

RESULTS

Children with (n = 5559) vs. without (n = 2.3 million) CP had a higher 5-year fracture risk at the vertebral column, hip, and lower extremities at almost each year of age, but lower 5-year fracture risk at the upper extremities after 6 years old (all P < 0.05). Among children with CP, the 5-year fracture rate was elevated for co-occurring neurological conditions and non-ambulatory status at the vertebral column, hip, and lower extremities (hazard ratio [HR] range, 1.44-2.39), and higher for males at the upper extremities (HR = 1.29) (all P < 0.05).

CONCLUSIONS

This study provides novel epidemiologic evidence of 5-year fracture risk for each year of age for children with CP.

IMPACT

This study provides novel epidemiologic evidence of 5-year fracture risk for each year of age across important developmental stages for children with vs. without cerebral palsy (CP). Children with vs. without CP were more likely to fracture at the vertebral column, hip, lower extremities, and humerus and less likely to fracture at the forearm and hands. The age-related 5-year fracture risk was associated with clinically relevant patient-level factors, but in different ways by fracture region. Study findings may be used to enhance clinical detection of at-risk children and strategize when to implement fracture prevention efforts for children with CP.

Application of Cortical Bone Plate Allografts Combined with Less Invasive Stabilization System (LISS) Plates in Fixation of Comminuted Distal Femur Fractures

Background and Objectives: At present, the management of comminuted distal femur fractures remains challenging for orthopedic surgeons. The aim of this study is to report a surgical treatment for comminuted distal femur fractures using supplementary medial cortical bone plate allografts in conjunction with the lateral less invasive stabilization system (LISS) plates. Materials and Methods: From January 2009 to January 2014, the records of thirty-three patients who underwent supplementary medial cortical bone plate allografts combined with lateral LISS plates fixation were reviewed. Clinical and radiographic data were collected during regular postoperative follow-up visits. Functional outcomes were determined according to the special surgery knee rating scale (HSS) used at the hospital. Results: Thirty patients were followed for 13 to 73 months after surgery, with an average follow-up time of 31.3 months. The mean time to bone union was 5.4 months (range of 3-12 months) and the mean range of knee flexion was 105.6° (range of 80-130°). Of the remaining patients, 10 had a score of "Excellent", while 10 had a score of "Good". Three patients had superficial or deep infections, one patient had nonunion that required bone grafting, and one patient had post-traumatic knee arthritis. Conclusions: Based on these promising results, we propose that supplementary medial cortical bone plate allografts combined with lateral LISS plate fixation may be a good treatment option for comminuted distal femur fractures. This treatment choice not only resulted in markedly improved stability on the medial side of the femur, but also satisfactory outcomes for distal femoral fractures.

Short-term outcomes of periprosthetic compared to native distal femur fractures, a national database study

BACKGROUND

Distal femur fractures (DFFx) are highly morbid injuries with a complication rate comparable to hip fractures. Rising rates of total knee arthroplasty (TKA) have led to increasing rates of periprosthetic DFFx (pDFFx). We sought to determine how pDFFx complication rates differed from native DFFx (nDFFx).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) was used to identify patients who sustained pDFFx or nDFFx between 2012 and 2018. Patients were further stratified by operative treatment: open reduction internal fixation (ORIF) or distal femur replacement (DFR). Multivariate logistic regression was used to compare 30-day complication rates between pDFFx versus nDFFx and, among pDFFx patients, ORIF versus DFR or revision TKA (rTKA).

RESULTS

563 patients with pDFFx and 2259 patients with nDFFx were identified between 2012 and 2018. pDFFx patients had significantly lower rates of ORIF than nDFFx patients (36.4 vs 95.4%, p < 0.001). On multivariate analysis, pDFFx were associated with a higher rate of surgical site complications (OR 2.48, p = 0.009) compared to nDFFx. There were no differences in mortality, reoperations, major complications, rate of blood transfusion, venous thromboembolism and disposition. In patients with pDFFx, patients undergoing DFR/rTKA were more likely to be discharged home versus a rehab facility, compared to those undergoing ORIF (OR 2.62, p < 0.001).

CONCLUSIONS

In this first large registry study comparing pDFFx and nDFFx, we find similar outcomes between these groups in the first 30 days after surgery. Patients with pDFFx did have higher rates of surgical site complications, including infection and dehiscence. In pDFFx patients, those undergoing DFR were more likely to return home post-operatively.

Modified use of the proximal humeral internal locking system (PHILOS) plate for distal femoral nonunions

PURPOSE

Nonunion is a common complication after a distal femoral fracture (DFF). Standard treatment consists of revision plating and/or bone grafting. Single lateral plating for a distal femoral nonunion can be insufficient in case of a persistent medial gap and compromised bone stock. Alternatively, dual plating can be used to treat a distal femoral nonunion, but to date there is no Gold standard. The aim of our study was to report our results after use of a minimally invasively placed proximal humeral internal locking system (Philos) plate as a medial buttress in the treatment of a distal femoral nonunion.

METHODS

Fifteen adult patients with a distal femoral nonunion were prospectively entered in a trauma database and retrospectively assessed. All patients underwent a similar operation, which included removal of failed hardware, nonunion debridement, fixation with a lateral plate, and a medial Philos plate combined with bone grafting. Data collected included union rate, time to union, complications and functional outcome.

RESULTS

In twelve out of fifteen patients (80%), the fracture united after our index operation. Median time to union was 4.8 months (range 1.6-15). Three patients (20%) needed additional bone grafting surgery. One patient underwent a Judet quadricepsplasty.

CONCLUSION

This study suggests that the Philos plate is a safe and effective adjunct as a medial buttress plate for distal femoral nonunions.

The comparison of stress and strain between custom-designed bone plates (CDBP) and locking compression plate (LCP) for distal femur fracture

BACKGROUND

Distal femur fracture is considered one of the most common fractures due to high-energy traumas such as car accidents or low-energy traumas such as osteoporosis. Locking plates are orthopedic implants used for stabilized femur fracture. Thus, designing a bone plate fitted exactly with the patient's bone and correctly fixing bone segments are required for better fracture healing.

OBJECTIVES

This study aims to design a bone plate based on anthropometric characteristics of patients' femurs and compare performing custom-designed bone plates (CDBP) with the locking compression plate (LCP) by finite element method.

MATERIALS AND METHODS

In this analytical study, a 3D model of four patients' femur and CDBP were firstly designed in MIMICS 19.0 based on the patient's femur anatomy. After designing the bone plate, the CDBPs and LCP were fixed on the bone and analyzed by finite element method (FEM) in ANSYS, and stress and strain of bone plates were also compared.

RESULTS

The maximum principal stress for all 3D models of patients' fracture femur by CDBPs was stabilized better than LCP with a decrease by 39.79, 12.54, 9.49, and 20.29% in 4 models, respectively. Also, in all models, the strain of CDBPs is less than LCP. Among the different thicknesses considered, the bone plate with 5 mm thickness showed better stress and strain distribution than other thicknesses.

CONCLUSION

Customized bone plate designed based on patient's femur anatomical morphology shows better bone-matching plate, resulting in increasing the quality of the fracture healing and fails to any need for additional shaping.

TRIAL REGISTRATION NUMBER

Design and analysis of an implant were investigated in this study. There was no intervention in the diagnosis and treatment of patients and the study was not a clinical trial.

The fragility of statistical significance in distal femur fractures: systematic review of randomized controlled trials

PURPOSE

The purpose of this study was to apply both the fragility index (FI) and fragility quotient (FQ) to evaluate the degree of statistical fragility in the distal femur fracture (DFF) literature. We hypothesized that the dichotomous outcomes within the DFF literature are statistically fragile.

METHODS

Using preferred reporting items for systematic reviews and meta-analyses, we performed a PubMed search for distal femur fractures clinical trials from 2000 to 2022 reporting dichotomous outcomes. The FI of each outcome was calculated through the reversal of a single outcome event until significance was reversed. The FQ was calculated by dividing each fragility index by study sample size. The interquartile range (IQR) was also calculated for the FI and FQ.

RESULTS

Of the 4258 articles screened, 92 met the search criteria, with eleven RCTs included for analysis. Ninety eight outcome events with 25 significant (P < 0.05) outcomes and 73 nonsignificant (P > 0.05) outcomes were identified. The overall FI and FQ for all 98 outcomes were 5 (IQR 4-6) and 0.130 (IQR 0.087-0.174), respectively. Three studies (33.3%) reported loss to follow (LTF) greater than 5.

CONCLUSIONS

The randomized controlled trials in the peer-reviewed distal femur fracture literature may not be as robust as previously thought, as incorporating statistical analyses solely on a P value threshold is misleading. Standardized reporting of the P value, FI and FQ can help the clinician reliably draw conclusions based on the fragility of outcome measures.

Complex distal femoral fracture treated with interfragmentary screws and medial buttress plating

A woman in her 70s suffered a motor vehicle accident, resulting in an intraarticular, distal femoral fracture with a unique fracture pattern. A 3D-printed model was obtained using the preoperative CT scan for surgical planning. Anatomic reduction was achieved using a medial parapatellar approach and the fracture was fixed with a medial buttress plate and interfragmentary screws. After 18 months, the patient presented a fair Knee Society Score of 62.

Micromotion-based balanced drilling technology to increase near cortical strain

Objective

A micromotion-based balanced drilling system was designed based on a locking plate (LP) and far cortical locking (FCL) concept to maintain the balance of micromotions of the cortex on both sides of a fracture region. The system was tested by axial compression test.

Methods

The fracture gap was set to 2 cm, and locking screws with a diameter of 5 mm and a locking plate were used to fix it. The diameters of the two sections of the stepping drill were 3.5 mm and 5.0 mm, respectively. One of the matching drilling sleeves was a standard sleeve (eccentricity, 0 mm) and the other was an eccentric sleeve (proximal eccentricity, 1 mm). A model of the fixed locking plate (AO/ASIF 33-A3) for distal femoral fractures with a gap of 2 cm was established based on data from 42 artificial femurs (SAWBONE). According to the shape of the screw holes on the cortex, the fixed fracture models were divided into a control group (standard screw hole group X126, six cases) and an experimental group (elliptical screw hole group N, 36 cases). The experimental group was further divided into six subgroups with six cases in each (N126, N136, N1256, N1356, N12356, N123456), based on the number and distribution of the screws on the proximal fracture segment. The control, N126, and N136 groups were subjected to an axial load of 500 N, and the other groups were subjected to an axial load of 1000 N. The displacements of the kinetic head, far cortex, and near cortex were measured. The integral structural stiffness of the model and the near cortical strain were calculated. The data of each group were analyzed by using a paired t-test.

Results

When the far cortical strains were 2%, 5%, and 10%, the near cortical strains in group N126 were 0.96%, 2.35%, and 4.62%, respectively, significantly higher than those in the control group (X126) (p < 0.05). For a different distribution of the screws, when the far cortical strains were 2%, 5%, and 10%, the near cortical strains in group N126 were significantly higher than those in group N136 (p < 0.05). However, there was no significant difference between the near cortical strains in the two groups with four screws (p > 0.05). For different numbers of screws, the near cortical strains in the three-screw groups were significantly higher than those in the four-screw groups (p < 0.05), and there was no significant difference in near cortical strains among the four-, five-, and six-screw groups (p > 0.05).

Conclusion

The proposed drill and matching sleeves enabled a conventional locking compression plate to be transformed into an internal fixation system to improve the balanced motion of the near and far cortices. Thus, strain on a fracture site could be controlled by adjusting the diameter of the drill and the eccentricity of the sleeve.

Biomechanical and anatomical considerations for dual plating of distal femur fractures: a systematic literature review

INTRODUCTION

Distal femur fractures are challenging injuries historically associated with high rates of nonunion and varus collapse with operative management. As a result, clinical and research interest in dual plating (DP) of distal femur fractures has seen a dramatic increase in recent years. The purpose of this study was to systematically review the literature regarding vascular anatomy and biomechanics of distal femur fractures treated with DP constructs.

MATERIALS AND METHODS

A systematic literature review of two medical databases (PubMed & Scopus) was performed to identify peer-reviewed studies on the anatomy and biomechanics regarding DP of distal femur fractures. A total of 1,001 papers were evaluated and 14 papers met inclusion criteria (6 anatomy and 8 biomechanics). Methodological quality scores were used to assess quality and potential bias in the included studies.

RESULTS

In the biomechanical studies, DP constructs demonstrated greater axial and rotational stiffness, as well as less displacement and fewer incidences of failure compared to all other constructs. Vascular studies showed that the femoral artery crosses the mid-shaft femur approximately 16.0-18.8 cm proximal to the adductor tubercle and it is located on average 16.6-31.1 mm from the femoral shaft at this location, suggesting that medial plate application can be achieved safely in the distal femur. The methodological quality of the included studies was good for biomechanical studies (Traa score 79.1; range 53-92.5) and excellent for anatomical studies (QUACs score 81.9; range 69.0-88.5).

CONCLUSIONS

Existing biomechanics literature suggests that DP constructs are mechanically stronger than other constructs commonly used in the treatment of distal femur fractures. Furthermore, medial distal femoral anatomy allows for safe application of DP constructs, even in a minimally invasive fashion. Dual plating should be considered for patients with distal femur fractures that have risk factors for instability, varus collapse, or nonunion.

Scattering and clustering the proximal screw construct in unilateral locking plate osteosynthesis of distal femoral fractures

INTRODUCTION

The importance of fixation construct in locking compression plate (LCP) is not well enlightened until recently. The aim of this study was to investigate radiological and clinical outcomes of scattering and clustering of the proximal screw fixation construct in unilateral LCP treatment of the distal femoral fractures.

MATERIALS AND METHODS

Patients who were treated for distal femoral fractures using unilateral LCP between January 2014 and December 2019 in our institute were included in this retrospective study. They were divided into groups 1 (35 cases, scattered proximal screw fixation) and 2 (35 cases, clustered proximal screw fixation). Mean follow-up period was 23.6 months for group 1 and 21.3 months for group 2. Medical history, patient demographics, injury characteristics, and surgical characteristics were reviewed and analyzed. Radiological findings including time to callus formation, bridging callus formation, union, and symmetry of the union were assessed and compared between the groups. Clinical outcomes included total blood loss during the operation, postoperative range of motion, and number of revision surgery.

RESULTS

The time for callus formation (5.8 weeks in group 1 vs. 4.1 weeks in group 2, p = 0.009) and bridging callus formation (12.5 weeks in group 1 vs. 10.7 weeks in group 2, p = 0.009) was significantly earlier in group 2. Despite similar union rates between groups, the mean time for radiological union was longer in group 2 (10.7 vs 7.4 months, p = 0.001). Though statistically insignificant, more asymmetric union was observed in group 2 (17 vs 11 cases).

CONCLUSIONS

Despite a delay in initial callus and bridging callus formation, scattering the proximal screws was better in achieving earlier and more balanced radiographic union than the clustered fixation. We recommend to avoid bridging more than five holes in the whole plate fixation construct to lessen the asymmetric callus formation and to prevent eventual plate breakage.

Investigation of distal femur microarchitecture and factors influencing its deterioration: An ex vivo high-resolution peripheral quantitative computed tomography study

While fractures of the distal femur are often considered as fragility fractures, detailed knowledge of the bone microarchitecture at this skeletal site is largely unavailable. Initial evaluation of a patient cohort with distal femur fractures showed a markedly increased occurrence in elderly women. The purpose of this study was to determine the extent to which demographic characteristics of distal femur fractures are reflected by general age- and sex-specific variations in local microarchitectural parameters. Fifty cadaveric femora were collected from 25 subjects (12 females, 13 males, age 25-97 years). A volume of interest within 3 cm proximal to the condyles was analyzed using high-resolution peripheral quantitative computed tomography (HR-pQCT), which revealed impaired trabecular and cortical bone microarchitecture in women compared to men as well as in osteoporotic compared to normal or osteopenic subjects, as classified by dual-energy X-ray absorptiometry (DXA) T-score. Linear regression analyzes showed negative associations between age and HR-pQCT parameters in women (e.g., cortical thickness -14 µm/year, 95% CI: -21 to -7 µm/year), but not in men (e.g., cortical thickness 1 µm/year, 95% CI: -12 to 14 µm/year). HR-pQCT parameters showed strong positive associations with areal bone mineral density (aBMD) determined by DXA at the hip in both sexes. Taken together, our findings suggest that female sex, advanced age, and low aBMD represent major risk factors for impaired microarchitecture at the distal femur. Both the diagnostic value of DXA for predicting distal femur fractures and the efficacy of bone-specific agents on fracture risk reduction should be investigated in the future.

Post-fracture rehabilitation pathways and association with mortality among adults with cerebral palsy

OBJECTIVE

Rehabilitation may mitigate the high mortality rates and health declines post-fracture for adults with cerebral palsy, but this is understudied. The objectives were to characterize the post-fracture rehabilitation pathways and identify their association with 1-year survival among adults with cerebral palsy.

METHODS

A retrospective cohort study of adults with cerebral palsy with a fragility fracture with continuous health plan enrollment ≥1-year prior to and ≥1 day after their fracture date was performed using a random 20% Medicare fee-for-service dataset. Participants were categorized as a home discharge or inpatient rehabilitation admission post-fracture. For the home discharge cohort, weekly exposure to outpatient physical/occupational therapy (PT/OT) was examined up to 6-month post-fracture. Cox regression examined the association between time-varying PT/OTuse within 6-month post-fracture and mortality from 30 days to 1-year post-fracture before and after adjusting for confounders (e.g. medical complexity).

RESULTS

Of 3598 adults with cerebral palsy with an incident fragility fracture, 74% were discharged home without inpatient rehabilitation; they were younger, but more medically complex compared to the 26% admitted to inpatient rehabilitation. Among the home discharge cohort (n = 2662), 43.1% initiated PT/OTwithin 6-month post-fracture, and cumulative PT/OTexposure post-fracture was associated with improved survival; for example, per 3 weeks of PT/OTexposure, the adjusted mortality rate was 40% lower (95% confidence interval (CI) = 0.41-0.89).

CONCLUSIONS

Most adults with cerebral palsy with a fragility fracture were discharged home rather than to inpatient rehabilitation, and only 43.1% of that group initiated outpatient PT/OTwithin 6 months post-fracture. Receiving outpatient PT/OTwas associated with improved 1-year survival.

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.

Practical approach to the native distal femur fractures in the elderly: A rapid review over the recent trends

Significant work has been done in recent years on treatment strategies for distal femur fractures. Inclusive reviews on periprosthetic fractures of distal femur have been carried out recently, but there is a lack of such reviews on the subject of native distal femur fractures in the recent literature. In this narrative review, we are set out to address the latest updates on geriatric non-periprosthetic distal femur fractures, and perform a rapid review over different treatment options, arriving at a summarized proposed treatment algorithm.

[Distal femoral fractures]

CLINICAL ISSUE

Fractures of the distal femur represent rare but serious injuries with a high 1‑year mortality. An increasingly older patient population requires adapted treatment concepts.

STANDARD TREATMENT PROCEDURE

Surgical treatment using angular stable plating and retrograde nailing is the standard procedure. Conservative treatment is only indicated in cases of low demands and high perioperative risks of the patient.

TREATMENT INNOVATIONS

Primary double plate osteosynthesis and primary implantation of a distal femoral replacement represent new treatment procedures and show promising initial results in the collective of geriatric patients.

DIAGNOSTIC WORK-UP

Conventional radiographs in 2 planes and computed tomography with multiplanar and 3D reconstructions should be performed to enable an adequate assessment of the indications and treatment planning.

PERFORMANCE

Nonunion rates of plate and nail osteosyntheses range from 4% to 10%. No significant differences in long-term results can be observed. The results regarding double plate osteosynthesis and distal femoral replacement so far do not show any disadvantages compared to the existing procedures but there is still insufficient data for general recommendations.

ASSESSMENT

Complex fractures with extensive reconstructive procedures and treatment by distal femoral replacement should be performed in specialized centers.

PRACTICAL RECOMMENDATIONS

The gold standard is still surgical treatment by means of minimally invasive angular stable plate or retrograde nail osteosynthesis. Complex fracture forms require individual treatment planning considering all currently available treatment options.

Application of Finite Element Analysis Combined With Virtual Computer in Preoperative Planning of Distal Femoral Fracture

Background

Distal femoral fractures are increasing with an aging population. The computer-assisted preoperative planning has great potential, but there are no preoperative plans to determine appropriate fixation methods for distal femoral fractures on an individual basis. The aims of this study are: (1) to describe the technique of finite element analysis combined with computer-assisted preoperative planning to determine a fixation method for distal femoral fractures and (2) to evaluate the intra-operative realization of this technology and the clinical outcomes based on it for distal femoral fractures.

Materials and Methods

Between January 2017 and January 2020, 31 patients with distal femoral fractures treated by open reduction and internal fixation were included and randomly divided into two groups based on preoperative planning methods: conventional group (n = 15) and computer-assisted group (n = 16). Firstly, how to determine the most appropriate plate and screw length and placement in the preoperative planning of distal femoral fractures was described. The time taken for preoperative planning for different fracture types in the computer-assisted group was then analyzed. Finally, intraoperative and postoperative parameters were compared between the conventional and computer-assisted groups, assessing operative time, intraoperative blood loss, number of intraoperative fluoroscopies, days of hospital stay, Visual Analog Scale for Pain Score (VAS), and Knee Society Score (KSS).

Results

Mean total planning time for 33-A, 33-B, and 33-C fractures in computer-assisted group were 194.8 ± 6.49, 163.71 ± 9.22, and 237 ± 5.33 min, respectively. Compared with the conventional group, the patients in the computer-assisted group had less blood loss, fewer fluoroscopic images, and shorter operation time (p < 0.05). However, there was no significant difference in the hospitalization days, KSS score and VAS score between the two groups (p > 0.05).

Conclusions

The results of this study show that finite element combined with computer-assisted preoperative planning can effectively help surgeons to make accurate and clinically relevant preoperative planning for distal femoral fractures, especially in the selection of appropriate plate length and screw positioning.

How does intraoperative fracture malalignment affect postoperative function and bone healing following distal femoral fracture?

Aims

Postoperative malalignment of the femur is one of the main complications in distal femur fractures. Few papers have investigated the impact of intraoperative malalignment on postoperative function and bone healing outcomes. The aim of this study was to investigate how intraoperative fracture malalignment affects postoperative bone healing and functional outcomes.

Methods

In total, 140 patients were retrospectively identified from data obtained from a database of hospitals participating in a trauma research group. We divided them into two groups according to coronal plane malalignment of more than 5°: 108 had satisfactory fracture alignment (< 5°, group S), and 32 had unsatisfactory alignment (> 5°, group U). Patient characteristics and injury-related factors were recorded. We compared the rates of nonunion, implant failure, and reoperation as healing outcomes and Knee Society Score (KSS) at three, six, and 12 months as functional outcomes. We also performed a sub-analysis to assess the effect of fracture malalignment by plates and nails on postoperative outcomes.

Results

The rates of nonunion and reoperation in group U were worse than those in group S (25.0% vs 14.3%; 15.6% vs 5.6%), but the differences were not significant (p = 0.180 and p = 0.126, respectively). Mean KSS in group U at all follow-up periods was significantly worse that in group S (75.7 (SD 18.8) vs 86.0 (SD 8.7); p < 0.001; 78.9 (SD 17.2) vs 89.1 (SD 9.8); p < 0.001; 85.0 (SD 11.9) vs 91.1 (SD 7.2); p = 0.002, respectively). In the sub-analysis of plates, mean KSS was significantly worse in group U at three and six months. In the sub-analysis of nails, the rate of reoperation was significantly higher in group U (28.6% vs 5.8%; p = 0.025), and mean KSS at six and 12 months was significantly worse in Group U.

Conclusion

To obtain good postoperative functional results, intraoperative alignment of the coronal plane should be accurately restored to less than 5°.

Cite this article: Bone Jt Open 2022;3(2):165–172.

Impact on periosteal vasculature after dual plating of the distal femur: a cadaveric study

Although dual plating of distal femur fractures has been described for injuries at risk of varus displacement, the vascular insult to the medial distal femur utilizing this technique is unknown. The aim of this study was to evaluate the perfusion of the medial distal femoral periosteal arteries after supplemental medial plating of the distal femur.

Methods

Fifteen human fresh-frozen cadaveric femora were thawed and randomized to lateral locked plating alone or with supplemental medial plate fixation. Conventional submuscular medial plating was performed using a 12-hole small fragment plate and multiple cortical screws. The superficial femoral artery was injected with latex dye. Specimens were dissected. The patency of the medial distal femoral periosteal vessels was evaluated.

Results

Four vessels were consistently observed traversing the distal medial femur: the transverse and descending (d-MMPA) branches of the medial metaphyseal periosteal artery, and the transverse and longitudinal branches of the descending geniculate artery. The anterior longitudinal arch (ALA) was present in 13 of 15 specimens and was fed by the d-MMPA. The median number of periosteal arteries occluded by the medial plate was 2 (6 out of 8 specimens). The d-MMPA was occluded in 6 of 8 medially plated femurs, resulting in a complete lack of perfusion of the ALA.

Conclusions

Submuscular medial plating of the distal femur compressed the d-MMPA in the majority of specimens. This vessel gives rise to the ALA, which lacked perfusion in these specimens. This vascular insult could affect the healing of metaphyseal distal femur fractures treated with dual plating.

Locking retrograde nail, non-locking retrograde nail and plate fixation in the treatment of distal third femoral shaft fractures: radiographic, bone densitometry and clinical outcomes

BACKGROUND

Distal third femoral shaft fractures are characterized by increasing incidence and complexity and are still considered a challenging problem (high morbidity and mortality). No consensus on best surgical option has been achieved. This study aims to investigate radiographic, mineral bone densitometry and clinical outcomes of locking retrograde intramedullary (LRN) nailing, non-locking retrograde intramedullary nailing and anatomical locking plate to surgically treat distal third femoral shaft fractures in young adults. Our hypothesis was that there is no significant statistical difference among the surgical options in terms of results (radiographic, bone densitometry and outcomes assessment).

METHODS

Retrospective study: 90 patients divided into three groups (group 1 LRN, group 2 NLRN, group 3 plating). Average age was respectively 42.67 (± 18.32), 44.27 (± 15.11) and 42.84 (± 18.32) years. Sex ratio F:M was respectively 2.75, 2.33 and 2.00. AO Classification, KOOS, NUSS and RUSH score, VAS, DEXA scans and plain radiographs were used. Evaluation endpoint: 12 months after surgery.

RESULTS

There were no statistical differences in terms of surgery time, transfusions, and wound healing. Results were similar with regard to average time of bone healing, RUSH scores, VAS, KOOS, regression between RUSH and VAS, average correlation clinical-radiographic results and patients outcomes.

CONCLUSIONS

Our results showed no statistical difference in the use of LNR, NLNR and plating for treatment of distal third femur shaft fractures in terms of radiographic, bone densitometry and clinical outcomes. Good subjective and objective results are provided by all three techniques. The choice among the studied techniques must be based on surgeons' experience, indications and subjective patients' aspects. The absence of relevant similar data in the published literature does not allow definitive validation (or rejection) of our hypothesis. A more powered study with a bigger cohort is needed for definitive validation.

Comparing Intramedullary Nailing Versus Locked Plating in the Treatment of Native Distal Femur Fractures: Is One Superior to the Other?

INTRODUCTION

Distal femur fractures make up < 1% of all fractures and 3-6% of all femur fractures. In the literature, both intramedullary nailing (IMN) and locked plating (LP) have shown favorable results, but there is no consensus on a gold standard. The purpose of this systematic review is to compare outcomes of native distal femur fractures treated via IMN versus LP in an effort to determine if one is superior to the other.

METHODS

Systematic review of MEDLINE, EMBASE, and Cochrane Library databases was conducted according to PRISMA guidelines. Only articles published within the last ten years were included. Evidence and study quality were evaluated with the MQOE and Oxford Criteria.

RESULTS

Forty-six articles were included in the review. Fractures treated with IMN were found to have a 93.9% union rate, an average time to union of 19.2 weeks, an average arc of motion of 105.1 degrees, with an average of 14.4 degrees of malalignment. Fractures treated with LP were found to have a 90.2% union rate, an average time to union of 20.5 weeks, an average arc of motion of 104 degrees, with an average of 12.6 degrees of malalignment.

CONCLUSION

Compiled data comparisons revealed no differences in union rate, malalignment, time to union, average arc of motion, or complication rates requiring a return to the operating room. Until higher level randomized data is available, either IMN or LP are acceptable methods of treatment for native distal femur fractures.

Application of a double reverse traction repositor in the retrograde intramedullary nailing of distal femur fractures

Objective

The purpose of this prospective study was to introduce the application of a double reverse traction repositor (DRTR) in the retrograde intramedullary nailing (RE-IMN) of AO/OTA 33A distal femur fractures.

Patients and methods

A total of 27 patients with AO/OTA type 33A distal femur fractures who were admitted from January 2015 to May 2017 to a level I trauma center of a tertiary university hospital were enrolled in this prospective study. A DRTR was used to facilitate RE-IMN for the reduction of distal femur fractures in all patients. The demographic and fracture characteristics, surgical data, postoperative complications, and prognostic indicators of 24 patients were recorded.

Results

The DRTR helped achieve and maintain the reduction of all distal femur fractures in the present study. All surgeries were conducted by closed reduction, and excellent alignment was observed in the postoperative X-ray images. In the present study, 18 males and 6 females were included, and the average age of all patients was 51.3 years (range, 24–68 years). The mean operation time, intraoperative blood loss, intraoperative fluoroscopy time, and length of postoperative hospital stay were 137 min (range from 80 to 210 min), 320 ml (range from 200 to 600 ml), 28 (from 24 to 33), and 9 days (from 5 to 14 days), respectively. Eleven patients were found to have postoperative deep venous thrombosis before discharge. No cases of wound infection were observed. No cases of nonunion or malunion were observed. The average follow-up duration was 21 months (18–30 months). The average HHS, LKFS, and VAS scores at the 1-year follow-up were 89.9 (86–97), 79.1 (75–87), and 2.1 (from 0 to 5). No complications associated with DRTR were found.

Conclusions

A DRTR can be successfully applied in the treatment of distal femur fractures with RE-IMN, and it can not only help achieve or maintain the reduction of distal femur fractures with closed methods but also promote fixation with RE-IMN.

Biphasic plating improves the mechanical performance of locked plating for distal femur fractures

Internal fixation by plate osteosynthesis is the gold standard treatment for distal femur fractures. Despite improvements that preserve the biological conditions for bone healing, there are concerns standard locked plating constructs may be overly stiff. Biphasic plating is a novel concept designed to provide suitable fracture motion and increased implant strength to support early full weight-bearing. This study aims to demonstrate that the Biphasic Plate can be incorporated into a pre-contoured distal femur plate while providing adequate flexibility and increased implant strength. The mechanical performance of the Biphasic Plate (BP) was investigated in comparison to a standard locking plate for the distal femur (LCP-DF). Constructs were formed by mounting the implants on a bone substitute. The construct stiffness and strength under axial loading and the magnitude of interfragmentary movement were determined using finite element analysis. The Biphasic Plate exhibited a bi-linear stiffness response; at low loads, the BP construct was 55% more compliant and at high loads 476% stiffer than the LCP-DF. The Biphasic Plate provided more consistent interfragmentary movement over a wider loading range. At partial weight-bearing loads, the Biphasic Plate produced larger interfragmentary movements (0.18 vs. 0.04 mm). However, at loads equivalent to full weight-bearing, the maximum movements were substantially smaller than the LCP-DF construct (1.5 vs. 3.5 mm). The increased flexibility at low loads was provided without sacrificing implant strength with peak stress in the Biphasic Plate 63% lower than the LCP-DF construct. The biphasic plating concept can be successfully incorporated into anatomically contoured distal femur plates while providing adequate flexibility and increasing implant strength.

Early Failure of a Carbon-Fiber-Reinforced Polyetheretherketone Distal Femur Plate: A Case Report

CASE

In this case, we report on a carbon-fiber-reinforced polyetheretherketone plate failure 4 months after implantation, radiation therapy, chemotherapy, and protective weight-bearing in a 75-year-old woman who sustained a nontraumatic pathological distal femur fracture due to lymphoma.

CONCLUSION

Although carbon-fiber composite implants are regularly used and, to date, there have been no reports of early clinical failures, the longevity of the implant's structural integrity after high-dose radiation and/or chemotherapy treatment has not been fully explored. Therefore, we deem it too early to conclude that carbon-fiber-reinforced polyetheretherketone implants are superior to conventional implants in treating (pathological) fractures.

Complication Rates after Lateral Plate Fixation of Periprosthetic Distal Femur Fractures: A Multicenter Study

OBJECTIVE

Periprosthetic fractures of the distal femur can be challenging injuries to treat; nonunion rates of up to 22% have been reported. The purpose of this study was to determine the rate of complications and nonunion in a multicenter series, and to identify patient or surgical factors that were associated with nonunion.

DESIGN

Retrospective comparative study SETTING: Three Level 1 trauma centers PATIENTS: Fifty-five patients with a periprosthetic distal femur fracture proximal to a total knee arthroplasty. Minimum follow up for inclusion was six months or until union or failure.

INTERVENTION

Surgical fixation using a precontoured lateral locking plate MAIN OUTCOME MEASUREMENT: Fracture union was the primary outcome. Patient demographic and injury variables (age, comorbidities, fracture classification and characteristics) and surgical technique factors (mode of plate fixation, plate material, working length, screw density, and proximal screw type) were identified and compared between patients who developed a nonunion and those who did not. Regression analysis was performed to identify independent risk factors for nonunion.

RESULTS

The overall rate of nonunion was 18% and the total complication rate was 24%. After additional surgery, 49 of 55 patients went on to heal (89%). There were no statistical differences in patient demographic or injury variables between the union and nonunion groups, and none of the variables studied were independent risk factors for nonunion in the regression analysis.

CONCLUSIONS

In this series of 55 patients with periprosthetic distal femur fractures treated with precontoured lateral locking plates, 18% developed nonunion and the overall complication rate was 24%. No patient or surgical variables were identified as risk factors. Future research should seek to identify patients at high risk for complication and nonunion who could benefit from alternative fixation strategies or distal femoral replacement.

Treatment of distal femur fractures with VA-LCP condylar plate: A single trauma centre experience

INTRODUCTION

Given the recent criticisms in the literature regarding Synthes Variable Angle Locking Compression Condylar Plate (VA-LCP), the purpose of this study was to evaluate functional outcome, fracture healing, and complications of distal femoral intra-articular fractures using this device.

METHODS

Patients with distal femoral fractures treated with 4.5 mm VA-LCP Curved Condylar Plate were included in this retrospective study. Follow-ups were at 4 weeks, 3 months, 6 months and 1 year. For the clinical and functional assessment of the knee, WOMAC, Koos Knee Survey, the Knee Score Society and the SF-12 questionnaire were used. Radiographically we assessed the fracture healing and the angles of the operated limb compared to the healthy contralateral limb. Complications have also been described.

RESULTS

Forty-two patients with distal femoral fractures were included in the study. The mean follow-up was 8 months. Most cases (57%) reported a type 33-A fracture. Radiological healing was achieved in 33 cases; the mean time required to heal was 13 weeks. Three patients had an early postoperative complication and four cases had a late complication. Five cases required additional surgical procedures. Most patients (47.2%) achieved a complete flexion of 130° or more. WOMAC mean value 27.4%, KSS mean value 77.6 for the clinical part and 60 for the functional part, KOOS mean score 60.1, SF-12 mean score 46.1 for MCS and 35.5 for PCS.

DISCUSSION

The results of this retrospective study suggest that VA-LCP Curved Condylar Plates have a good functional outcome and fracture healing similar to other standard distal femoral locking plates. VA technology allows greater versatility in fractures internal fixation regardless of the plate design. Fixation devices or Prosthesis implants previously placed may be avoided, as in periprosthetic fractures. Moreover, we have not recorded any early mechanical damage.

CONCLUSIONS

Osteosynthesis with Synthes 4.5 mm VA-LCP Curved Condylar Plate demonstrated to have no early mechanical failure rate with good clinical and radiological results.

[Distal femoral fractures]

With a prevalence of approximately 0.4%, distal femoral fractures are a rare entity. Nevertheless, due to the high mortality rates, which are comparable to proximal femoral fractures, these fractures are highly important. The clinical symptoms are often quite striking. In combination with preoperative computed tomography (CT) and if necessary, supplemented by CT angiography, the morphological situation can be assessed and the decision making facilitated. There are several different treatment options and the appropriate one should be selected for each individual case. The use of external fixation of the complete knee joint in the sense of damage control surgery, is useful. For definitive treatment retrograde intramedullary nailing and locking plates with angle stable screws are the main options. Modern angle stable and anatomically preformed implants enable surgical treatment using minimally invasive approaches to protect the soft tissues, with a better overall outcome.

Analysis of the fit of modern pre-contoured distal femur plates: Expect an imperfect contour

The purpose of this study was to determine if the contour of current distal femur plates can reliably be used as a reduction tool and to determine if the presence of a total knee arthroplasty (TKA) influences fit. Thirty-two patients were retrospectively reviewed. Radiographs of 19 patients with normal knees and 21 patients who had undergone TKA were evaluated. Using TraumaCad templating software, the contours of 4 different modern distal femur plates (Depuy Synthes, Stryker, Zimmer Biomet, and Smith & Nephew) were analyzed using a novel measurement technique to evaluate plate fit. To mimic non-locking screws in the shaft, the template was placed on the shaft and the plate to bone (PTB) and condyle to plate (CTP) distances were recorded. The PTB distance measured how closely the plate matched the contour of the metaphyseal flare, while the CTP value represented the distance from the plate to the distal articular surface. Larger PTB and CTP distances represent a higher mismatch between the patient's anatomy and the contour of the plate. There was significant variability in plate fit in all patients. None of the plates fit the patient's anatomy well, with PTB values averaging from 5.5 mm to 9.2 mm. There was no significant difference between normal radiographs and TKA radiographs, suggesting that the presence of a TKA may not contribute to plate fit. The results of this study show that current plate designs may not match the patient's native anatomy prior to fracture. Therefore, caution should be utilized when using non-locking screws in the shaft and using the pre-contoured nature of the plate as a template for reduction. The authors advocate for careful preoperative planning and using contralateral radiographs for templating purposes to prevent malreduction and to assist in device selection for the best device fit per patient.

Radiographic, Bone Densitometry and Clinic Outcomes Assessments in Femoral Shaft Fractures Fixed by Plating or Locking Retrograde Nail

Introduction:

Distal femoral shaft fractures are characterized by increasing incidence and complexity and are still considered a challenging problem (high morbidity and mortality). No consensus on best surgical option has been achieved.

Aim:

This study aims is to investigate radiographic, mineral bone densitometry and clinical outcomes of locking retrograde intramedullary (LRN) nailing and anatomical locking plate to surgically treat distal femoral shaft fractures in young adults based on the hypothesis that there is no statistical difference among the two surgical options in terms of results (radiographic, bone densitometry and outcomes assessment).

Methods:

Retrospective study: 30 patients divided into 2 groups (Group 1 LRN, Group 2 Nailing). Average age was 42.67±18.32 for Group 1 and 42.84 ±18.32 for Group 2 (range of age 18-65 for both groups). Gender Ratio (male: female) was 2.75 (11:4) for both Group 1 and 2. AO Classification, NUSS and RUSH score, VAS, Dexa scans, plain radiographs were used. Evaluation endpoint: 12 months after surgery (mean follow up 16.24).

Results:

No statistical difference in terms of surgery time, transfusions, wound healing. Similar results with regard to average time of bone healing, RUSH scores, VAS, regression between RUSH and VAS, average correlation clinical-radiographic results and patients outcomes. Only one patient of each group had reduction of mineral bone densitometry values.

Conclusion:

No statistical difference about the use of LNR or Nailing for treatment of distal femur shaft fractures in terms of radiographic, bone densitometry and outcomes has been found accordingly to our results. Good subjective and objective results are provided by both techniques. The choice among the two techniques must be based on surgeons’ experience, indications and subjective patients’ aspects. The absence of relevant similar data in the published literature does not allow definitive validation (or rejection) of our hypothesis. A more powered study with bigger cohort is needed for definitive validation.

Treatment of open intraarticular distal femur fractures by Ilizarov fixator; an approach to improve the outcome with mid-term results

PURPOSE

Open comminuted intraarticular distal femur fracture represents a formidable challenge for the orthopaedic surgeon for the inherent fracture complexity, soft tissue damage, and contamination. The purpose of this study was to evaluate the mid-term outcome results and safety of using the Ilizarov fixator to treat these fractures.

PATIENTS AND METHODS

The study included 22 fractures treated by debridement with reduction and stabilization by Ilizarov external fixator. The mean age was 35 years. Gustilo grade of open fracture was III-A (19 cases), III-B (2 cases), and III-C (1 case). Six fractures were AO-OTA type 33C2, and 16 cases were type 33C3. Eight patients had associated injuries. Bone and functional results were evaluated by Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria, and Neer knee score. The statistical analysis was done using the IBM SPSS Statistics for Windows.

RESULTS

Seven cases had autogenous bone grafting. The frame crossed the knee in 8 patients. The fixator was removed after a mean of 7 months with union in all cases, and without any malalignment >5°. Deep infection occurred in two cases. Quadriceps-plasty was needed for 3 cases. After a mean of 44 months, the last follow-up results showed full knee extension and a mean flexion of 107.59°. The ASAMI functional and bone results were good to excellent in all cases. Neer knee score averaged 86.59.

CONCLUSIONS

Ilizarov fixator was an effective treatment modality of open comminuted distal femur fractures with high union rate, adequate alignment and satisfactory functional outcomes.

Distal Femur Locking Plates Fit Poorly Before and After Total Knee Arthroplasty

OBJECTIVE

To evaluate the fit of distal femur locking plates. Secondarily, we sought to compare plate fit among patients with and without a total knee arthroplasty (TKA).

DESIGN

Retrospective.

SETTING

University hospital.

INTERVENTION

Standard length precontoured distal femur locking plates from 4 manufacturers were digitally templated onto each patient's pre-TKA and post-TKA radiographs.

MAIN OUTCOME MEASUREMENTS

The maximum distance from the plate to the lateral femoral cortex (plate-bone distance) was measured in the metaphyseal region. Mean plate-bone distances were compared between manufacturers and between pre-TKA and post-TKA radiographs.

RESULTS

All implants tested were undercontoured in all patients. Plate-bone distances ranged from 6.6 ± 0.4 mm to 8.0 ± 0.4 mm (mean ± SE) pre-TKA and 8.2 ± 0.3 mm to 8.6 ± 0.3 mm after TKA, indicating worse fit after arthroplasty (P < 0.001). There were also intermanufacturer differences, with Synthes and Smith & Nephew implants demonstrating the lowest plate-bone distances in the pre-TKA and post-TKA groups, respectively. Proportionally, plate-bone increase was greater in the female cohort (16%) compared with the male cohort (8%).

CONCLUSIONS

There was plate-bone mismatch for the distal femur locking plates tested in this study, due to undercontouring of the implants. After patients underwent TKA, poor implant fit was exacerbated. Surgeons must be aware of the potential for deformity if the proximal segment is brought into contact with the implant. These finding may help optimize implant design for the treatment of periprosthetic distal femur fractures.

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.

Intraoperative Assessment of Coronal Alignment in Distal Femur Fracture Fixation: Technical Trick

Supracondylar femur fractures represent a challenging and common injury treated by many orthopedic surgeons. An array of surgical fixation options has been developed to help the treating surgeon restore normal anatomic alignment of these fractures, and lateral precontoured condylar femoral locking plates have become a common implant for most surgeons in treating these fractures. Although these precontoured plates provide significant benefit to the treating physician in regards to gaining appropriate bony fixation, common technical errors that may lead to malalignment when using these plates have been described. Avoiding these errors will help improve patient outcomes. Here, we describe a novel, inexpensive, and universally available technique that may aid the treating surgeon in restoring coronal alignment when treating distal femur fractures.

Early Comparative Outcomes of Carbon Fiber-Reinforced Polymer Plate in the Fixation of Distal Femur Fractures

OBJECTIVE

To evaluate the early clinical results of distal femur fractures treated with carbon fiber-reinforced polyetheretherketone (CFR-PEEK) plates compared with stainless steel (SS) lateral locking plates.

DESIGN

Retrospective comparative cohort study.

SETTING

ACS Level I trauma center.

PATIENTS/PARTICIPANTS

Twenty-two patients (11 SS, 11 CFR-PEEK) with closed distal femur fractures treated by a single surgeon over a 6-year period.

MAIN OUTCOME MEASUREMENTS

Nonunion, hardware failure, reoperation, time to full weight-bearing, and time union were assessed.

RESULTS

The CFR-PEEK cohort was on average older (71 vs. 57 years, P = 0.03) and more likely to have diabetes (P = 0.02). Nonunion was diagnosed in 4/11 (36%) patients in the SS group and 1/11 (9%) patients in the CFR-PEEK group (P = 0.12). Hardware failure occurred in 2 SS patients (18%) compared with none in the CFR-PEEK group (P = 0.14). Time to full weight-bearing was similar between groups, occurring at 9.9 and 12.4 weeks in the CFR-PEEK and SS groups, respectively (P = 0.23). Time to radiographic union averaged 12.4 weeks in the SS group and 18.7 weeks in the CFR-PEEK group (P = 0.26). There were 4 reoperations in the SS group and 1 in the CFR-PEEK group (P = 0.12).

CONCLUSIONS

CFR-PEEK plates show encouraging short-term results in the treatment of distal femur fractures with a comparable nonunion, reoperation, and hardware failure rates to those treated with SS plates. This data suggest that CFR-PEEK plates may be a viable alternative to SS plates in fixation of these fractures.

LEVEL OF EVIDENCE

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

Lateral locked plating for distal femur fractures by low-energy trauma: what makes a difference in healing?

PURPOSE

The objective of this study is to investigate healing outcome of lateral locked plating for distal femoral fractures caused by low-energy trauma. In addition, we sought to determine predictable factors associated with fracture healing time.

METHODS

Seventy-three patients (73 fractures) with distal femur fractures (AO/OTA type 33) caused by low-energy trauma were recruited. The mean age of patients was 69.8 years (range, 43-87 years). All fractures were stabilized by less invasive osteosynthesis with anatomical periarticular locking system. Patients were followed up for mean 17.3 months (range, 6-44 months).

RESULTS

Of the 73 fractures, 52 (71.2%) fractures showed bony union within 6 months after the index surgery while the remaining 21 (28.8%) fractures showed delayed union or received revision surgery prior to complete healing. Although overall healing rate from the initial surgery was 93.2% (68/73), which seems to be satisfactory, the rate of surgical complications was 11.0% (8/73). Of all 73 fractures, seven received further surgery including three re-osteosynthesis. On multivariable analysis, plate-screw density at the fracture site was an independent predictable factor associated with the problematic healing.

CONCLUSIONS

Our findings suggest that complications related to increased healing time and fixation construct are not infrequent and ongoing problems in managing low-energy distal femur fractures. Specifically, plate-screw density at the fracture site has a significant influence on healing time in these fractures.

Healing, nonunion, and re-operation after internal fixation of diaphyseal and distal femoral fractures: a systematic review and meta-analysis

PURPOSE

Nonunion is a highly morbid complication that exacerbates the pain, disability and financial burden of distal and diaphyseal femur fractures. This study examined the modern rates of healing, nonunion, and other complications requiring reoperation of different fixation methods for distal and diaphyseal femur fractures.

METHODS

A systematic review and meta-analysis of all records from PubMed, Embase and the Cochrane Review system was performed. Included studies had >20 acute, non-pathologic distal or diaphyseal femur fractures treated with primary internal fixation. Excluded were studies on abnormal patient/fracture populations, external fixation, or cement/bone graft use.

RESULTS

Thirty-eight studies with 2,829 femoral shaft fractures and 11 studies with 505 distal femur fractures were included. Distal fractures had a lower healing rate (86.6% vs. 93.7%) and a higher re-operation rate (13.4% vs 6.1%) than shaft fractures (p < 0.00001), primarily due to higher rates of mechanical failure (p < 0.00001). Nonunion was the most frequent complication, occurring in 4.7% of distal fractures and 2.8% of shaft fractures. There was no difference between plate and nail fixation of distal fractures in healing, nonunion, or other causes of re-operation. Shaft fractures developed nonunion in 6.6% of unreamed nails and 2.1% of reamed nails (p = 0.002). Nonunion occurred in 2.3% of antegrade nailed fractures and 1.5% of retrograde nailed fractures (p = 0.66).

CONCLUSIONS

Approximately one out of every eight distal fractures and one of every 16 shaft fractures requires re-operation. The most common cause of fixation failure is nonunion. Further research is needed to improve outcomes, particularly in distal femur fractures.