Predictive factors of distal femoral fracture nonunion after lateral locked plating: a retrospective multicenter case-control study of 283 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.

Geriatric Distal Femur Fractures Treated with Arthroplasty Are Associated with Lower Mortality but Greater Costs Compared with Open Reduction and Internal Fixation at 30 Days

Distal femur fractures (DFFs) are common injuries with significant morbidity. Surgical options include open reduction and internal fixation (ORIF) with plates and/or intramedullary devices or a distal femur endoprosthesis (distal femur replacement [DFR]). A paucity of studies exist that compare the two modalities. The present study utilized a 1:2 propensity score match to compare 30-day outcomes of geriatric patients with DFFs who underwent an ORIF or DFR. The National Surgical Quality Improvement Program data from 2008 to 2019 were utilized to identify all patients who sustained a DFF and underwent either ORIF or DFR. This yielded 3,197 patients who underwent an ORIF versus 121 patients who underwent a DFR. A final sample of 363 patients (242 patients with ORIF vs. 121 with DFR) was obtained after a 1:2 propensity score match. Costs were obtained from the National Inpatient Sample database using multiple regression analysis and validated with a 7:3 train-test algorithm. Independent samples t-tests and chi-square analysis were conducted to assess cost and outcome differences, respectively. Patients who received a DFR had higher transfusion rates than ORIF (p = 0.021) and higher mean inpatient hospital costs (p = 0.001). Subgroup analysis for patients 80 years of age or older revealed higher 30-day unplanned readmission (0 vs. 18.2%; p < 0.001) and 30-day mortality (0 vs. 18.2%; p < 0.001) rates for patients undergoing ORIF compared with DFR. The total number of DFR cases needed to prevent one ORIF-related 30-day mortality for DFR for patients 80 years of age was 6 (95% confidence interval: 3.02-19.9). The mean hospital costs associated with preventing one case of death within 30 days from operation by undergoing DFR compared with ORIF was $176,021.39. Our results demonstrate higher rates of transfusion and increased inpatient costs among the DFR cohort compared with ORIF. However, we demonstrate lower rates of mortality for patients 80 years and older who underwent DFR versus ORIF. Future studies randomized controlled trials are necessary to validate the results of this study.

Delayed Union and Nonunion: Current Concepts, Prevention, and Correction: A Review

Surgical management of fractures has advanced with the incorporation of advanced technology, surgical techniques, and regenerative therapies, but delayed bone healing remains a clinical challenge and the prevalence of long bone nonunion ranges from 10 to 15% of surgically managed fractures. Delayed bone healing arises from a combination of mechanical, biological, and systemic factors acting on the site of tissue remodeling, and careful consideration of each case's injury-related, patient-dependent, surgical, and mechanical risk factors is key to successful bone union. In this review, we describe the biology and biomechanics of delayed bone healing, outline the known risk factors for nonunion development, and introduce modern preventative and corrective therapies targeting fracture nonunion.

Risk Factors of Failure in 228 Periprosthetic Distal Femur Fractures: A Multicenter Study

OBJECTIVES

To identify risk factors of reoperation to promote union or to address deep surgical-site infection (DSSI) in periprosthetic distal femur fractures treated with lateral distal femoral locking plates (LDFLPs).

METHODS

DESIGN

Multicenter retrospective cohort study.

SETTING

Ten level-I trauma centers.

PATIENT SELECTION CRITERIA

Patients with Orthopaedic Trauma Association/Association of Osteosynthesis (OTA/AO) 33A or 33C periprosthetic distal femur fractures who underwent surgical fixation between January 2012 and December 2019 exclusively using LDFLPs were eligible for inclusion. Patients with pathologic fractures or with follow-up less than 3 months without an outcome event (unplanned reoperation to promote union or for deep surgical infection) before this time point were excluded. Fracture fixation constructs used medial plates, intramedullary nails, or hybrid fixation constructs were excluded from analysis.

OUTCOME MEASURES AND COMPARISONS

To examine the influence of patient demographics, injury characteristics, and features of the fracture fixation construct on the occurrence of unplanned reoperation to promote union or to address a DSSI.

RESULTS

There was an 8.3% rate (19/228) of unplanned reoperation to promote union. Predictive factors for the need for reoperation to promote union included increasing body mass index (odds ratio [OR] = 1.09; 95% confidence interval [CI]: 1.02-1.16; P = 0.01), increasing number of screws in the distal fracture segment (OR = 1.73; 95% CI: 1.06-2.95; P = 0.03), and decreasing proportion of proximal segment screws that are locking (OR = 0.17; 95% CI: 0.03-0.70; P = 0.02) There was a 4.8% rate (11/228) of reoperation to address DSSI. There were no statistically significant predictive factors identified as risk factors of the need for reoperation to address DSSI ( P > 0.05).

CONCLUSIONS

8.3% of periprosthetic distal femur fractures treated at 10 centers with LDFLPs underwent unplanned reoperation to promote union. Increasing patient body mass index and increasing number of screws in the distal fracture segment were found to be predictive factors, whereas increased locking screws in the proximal segment were found to be protective. 4.8% of patients in this cohort underwent reoperation to address DSSI.

LEVEL OF EVIDENCE

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

Treatment of supracondylar femoral fractures by minimally invasive techniques vs. exposure of the fracture site: A retrospective cohort study

INTRODUCTION

Fractures of the distal femoral third are an important cause of morbidity and mortality, and their treatment is currently controversial.

OBJECTIVES

To compare the results between minimally invasive techniques versus exposure of the fracture site. Secondly, to evaluate the relationship between demographic factors, mechanism of injury and surgical delay with patient prognosis.

METHOD

Retrospective cohort study carried out between 2015 and 2021 in a tertiary hospital. Data collection was performed by reviewing medical histories, measuring demographic and hospital parameters and definitive treatment strategy. One year of follow-up was completed in all patients, assessing the occurrence of surgical complications and mortality. A stratified analysis of the variables of interest was performed among patients over 65 years of age.

RESULTS

128 fractures were recorded, with definitive osteosynthesis being performed in 117. Patients who underwent minimally invasive techniques required a shorter hospital stay (9 [7-12] vs. 12 [8.75-16] days) (p=0.007), with no differences in mortality or complications during follow-up. In those over 65 years of age, opening the fracture site was associated with an increased risk of infection compared to minimally invasive techniques (33.3% vs. 2%) (p=0.507). All the deceased were patients over 65 years of age (33.7% at one year). Surgical delay longer than 48hours increased mortality by 10% among those older than 65 years (p=0.3). High-energy trauma had a higher proportion of pseudarthrosis (27.6% vs. 6.1%) (p=0.011).

CONCLUSIONS

Minimally invasive techniques decreased hospital stay but not complications or long-term mortality.

LEVEL OF EVIDENCE

IIb.

Risk factors for nonunion of osteoporotic vertebral compression fracture: a case‒control study

BACKGROUND

Early assessment of the risk of nonunion in osteoporotic vertebral compression fracture (OVCF) is beneficial to early clinical decision making. However, a comprehensive understanding of the risk factors for OVCF nonunion is lacking.

METHODS

We conducted a case-control study to investigate risk factors for OVCF nonunion. Patients who underwent surgery for nonunited OVCFs between January 2011 and December 2021 were eligible for inclusion as cases. Patients with successful OVCF healing confirmed by MRI over the same period were identified as controls. Patient demographics, comorbidities, and fasting blood test data were extracted for analysis.

RESULTS

A total of 201 patients with nonunited OVCFs and 1044 controls were included to evaluate the risk factors for nonunited OVCFs. There were statistically significant differences in sex, age, number of patients with hypertension, number of patients on bed rest after OVCF and T-score of BMD between the two groups. Logistic regression showed that female patients had a higher risk of OVCF nonunion than male patients and that smoking, drinking, diabetes, and hypertension were risk factors for nonunion of OVCFs, while bed rest and spinal support were protective factors against nonunion of OVCFs. We also found that age, BMD, FBG, and β-CTX were positively correlated with nonunited OVCFs, and that HGB and 1,25-(OH)2VitD3 level were negatively correlated with nonunited OVCFs.

CONCLUSION

Smoking, drinking, diabetes and hypertension were risk factors for nonunion of OVCFs, while bed rest and spinal support were protective factors against nonunion of OVCFs. Age, BMD, FBG and β-CTX were positively correlated with nonunited OVCFs, while HGB and 1,25-(OH)2VitD3 level were negatively correlated with nonunited OVCFs. Based on the results of our study, we suggest that bed rest or spinal support for at least 3 consecutive weeks is necessary to reduce the risk of OVCFs nonunion.

Severity of Complications after Locking Plate Osteosynthesis in Distal Femur Fractures

Background: Locked plating for distal femur fractures is widely recommended and used. We systematically reviewed clinical studies assessing the benefits and harms of fracture fixation with locked plates in AO/OTA Type 32 and 33 femur fractures. Methods: A comprehensive literature search of PubMed, Embase, Cinahl, Web of Science, and the Cochrane Database was performed. The studies included randomized and non-randomized clinical trials, observational studies, and case series involving patients with distal femur fractures. Studies of other fracture patterns, studies conducted on children, pathological fractures, cadaveric studies, animal models, and those with non-clinical study designs were excluded. Results: 53 studies with 1788 patients were found to satisfy the inclusion and exclusion criteria. The most common harms were nonunion (14.8%), malunion (13%), fixation failure (5.3%), infection (3.7%), and symptomatic implant (3.1%). Time to full weight-bearing ranged from 5 to 24 weeks, averaging 12.3 weeks. The average duration of follow-up was 18.18 months, ranging from 0.5 to 108 months. Surgical time ranged between 40 and 540 min, with an average of 141 min. The length of stay in days was 12.7, ranging from 1 to 61. The average plate length was ten holes, ranging from 5 to 20 holes. Conclusion: This review aimed to systematically synthesize the available evidence on the risk associated with locked plating osteosynthesis in distal femur fractures. Nonunion is the most common harm and is the primary cause of reoperation. The overall combined risk of a major and critical complication (i.e., requiring reoperation) is approximately 20%.

Development and validation of predictive nomogram for postoperative non-union of closed femoral shaft fracture

Closed femoral shaft fracture is caused by high-energy injuries, and non-union exists after operation, which can significantly damage patients' body and mind. This study aimed to explore the factors influencing postoperative non-union of closed femoral shaft fractures and establish a predictive nomogram. Patients with closed femoral shaft fractures treated at Hebei Medical University Third Hospital between January 2015 and December 2021 were retrospectively enrolled. A total of 729 patients met the inclusion criteria; of them, those treated in 2015-2019 comprised the training cohort (n = 617), while those treated in 2020-2021 comprised the external validation cohort (n = 112). According to multivariate logistic regression analysis, complex fractures, bone defects, smoking, and postoperative infection were independent risk factors. Based on the factors, a predictive nomogram was constructed and validated. The C-indices in training and external validation cohorts were 0.818 and 0.781, respectively; and the C-index of internal validation via bootstrap resampling was 0.804. The Hosmer-Lemeshow test showed good fit of the nomogram (P > 0.05) consistent with the calibration plot results. The clinical effectiveness was best at a threshold probability of 0.10-0.40 in decision curve analysis. The risk prediction for patients with fractures using this nomogram may aid targeted prevention and rehabilitation programs.

Comparison of radiological and functional results in osteoporotic distal femur fractures operated with single plating, lateral incision, and double plating, anterior paramedial incision: A retrospective study

Treatment of osteoporotic distal femur fractures is often complicated by a high rate of nonunion and varus collapse. For such fractures, lateral plating with lateral incision and double plating with anterior paramedial incision have shown promising results in the recent literature. The hypothesis of this study was that bilateral plating of comminuted distal femur fractures in osteoporotic patients would result in higher union rates and lower revision rates compared to an isolated lateral locking plate. The study included 56 patients (23 males, 33 females) with supracondylar femur fracture. According to the OA/OTA classification, 9 were type A3, 8 were A2, 13 were C1, 16 were C2, and 10 were C3. The mean follow-up period was 12 months, with 29 patients treated using lateral mini-incision, lateral locking plate, and 27 patients treated with anterior paramedial incision, dual plating. The clinical and radiological results were evaluated. The mean duration of radiological union in the studied population was 15 ± 2.1 months (range, 11-21 months) in the single plate group (Group A), and 13.5 ± 2.6 months (range, 9-19 months) in the double plate group (Group B). Mean ROM was 112.3° and flexion contracture 4° in Group A, and ROM 108.3° and flexion contracture 6.7° in Group B. (P = .15). The average Western Ontario and McMaster Universities Arthritis Index (WOMAC) score was 85.6 points in Group A and 83.5 points in Group B (P = .2278). The postoperative anteversion measurement in the operated extremity ranged from -15 to 19 in Group A, and from 5 to 18 in Group B. When the anteversion degrees were compared between the injured and uninjured extremities in the postoperative period, a significant difference was observed within Group A (P = .0018), but no significant difference was observed in Group B (P = .2492). Dual plate fixation using the anterior paramedial approach is an effective operative method for osteoporotic distal femur fractures. This has many advantages such as precise exposure, easy manipulation, anatomic reduction, and stable fixation. However, for surgical indications and medial bone defects > 1 cm, grafting should be performed.

What Is the Likelihood of Union and Frequency of Complications After Parallel Plating and Supplemental Bone Grafting for Resistant Distal Femoral Nonunions?

BACKGROUND

Management of resistant distal femur nonunions is challenging because patients not only have disability from an unhealed fracture, but also often have a shortened femur, stiff knee, deformities, and bone defects to address during revision surgery. Dual plating of the distal femur in such a setting can maintain stability that allows the nonunion to heal while also addressing bone defects and correcting deformities simultaneously. Dual-plating techniques that have been described lack standardization with regard to the size and type of medial-side implants and configuration of the dual-plate construct.

QUESTIONS/PURPOSES

(1) What proportion of patients achieve radiologic evidence of union after parallel plating of resistant distal femoral nonunions? (2) What improvements in function are achieved with this approach, as assessed by improvements in femoral length discrepancy, knee flexion, and patient-reported outcome scores? (3) What complications are associated with the technique?

METHODS

Between 2017 and 2020, the senior author of this study treated 38 patients with resistant distal femoral nonunions, defined here as nonunions that persisted for more than 12 months since the injury despite a minimum of two previous internal fixation procedures. During the study period, our preferred technique for treating aseptic, resistant distal femoral nonunions was to use dual plates in a parallel configuration augmented with autografts. Of 38 patients, three patients with active signs of infection who underwent resection and reconstruction using bone transport techniques and two patients older than 65 years with deficient distal femur bone stock who underwent endoprosthetic reconstruction were excluded. Of the 33 included patients, 67% (22 of 33) were male. The median age was 40 years (range 20 to 67 years). Nonunion was articular and metaphyseal in 13 patients and metaphyseal only in 20 patients. Our surgical approach was to remove existing implants, perform intraoperative culturing to rule out infection, debride the nonunion, correct the deformity, perform intra-articular and extra-articular lysis of adhesions with quadriceps release, and apply fixation using medial and lateral fixed-angle anatomic locked implants positioned in a parallel configuration. Every attempt to improve length was undertaken, and the defects were filled with autografts. A total of 97% of patients were followed until union occurred (one of 33 was lost to follow-up before union was documented), and 79% (26 of 33) were assessed for functional outcomes at a minimum of 2 years (median 38 months [range 25 to 60 months]) after excluding patients lost to follow-up and those in whom union did not occur after parallel plating. Union was defined as evidence of central trabecular bridging on AP radiographs and posterior cortical bridging on lateral radiographs. These radiologic criteria were defined to overcome difficulties in assessing radiologic healing in patients with lateral and medial plates. With parallel plating, bridging trabecular bone along the posterior cortex on lateral radiographs and the central region on AP radiographs is visualized and can be appreciated and interpreted as evidence of healing in two orthogonal planes. Preoperative and follow-up clinical assessment of knee ROM, the extent of femoral length correction based on calibrated femoral radiographs before and after surgery, and the evaluation of improvement in lower limb function based on the preoperative and follow-up differences in responses to the lower extremity functional scale (LEFS) were studied (the LEFS is scored from 0 to 80, with higher scores representing better function). Complications and secondary surgical procedures to address them were abstracted from a longitudinally maintained trauma database.

RESULTS

Sixty-seven percent (22 of 33) of nonunions showed radiologic healing by 24 weeks, and another 24% (eight of 33) healed by 36 weeks. Six percent (two of 33) did not unite, and one patient was lost to follow-up before union was documented. In the 79% (26 of 33) of patients available for final functional outcome assessment, the median femoral shortening had improved from 2.4 cm (range 0 to 4 cm) to 1.1 cm (range 0 to 2.3 cm; p < 0.001), and the median knee ROM had improved from 70° (range 20° to 110°) to 100° (range 50° to 130°; p = 0.002) after surgery. The median LEFS score improved to 63 (range 41 to 78) compared with 22 (range 15 to 33; p < 0.001) before surgery. Serious complications, including major thromboembolic events, iliac graft site infection, knee stiffness (flexion < 60°), and medial plate impingement necessitating removal, were seen in 30% (10 of 33) of patients. Secondary surgical interventions were performed in 24% (eight of 33) of patients to address procedure-related complications.

CONCLUSION

Based on our findings, a high likelihood of union and improvements in knee and lower limb function can be expected with parallel plating of resistant distal femur nonunions using anatomic locked plates. However, the increased frequency of complications observed in our study suggests the need for improvements in dual-plating techniques and to explore possible alternative fixation methods through larger multicenter comparative studies.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Supplementary medial plating in revision surgery for distal femoral fractures: A surgical technique with clinical outcomes

INTRODUCTION

Distal femur fractures (DFF) are common, especially in the elderly and high energy trauma patients. Lateral locked osteosynthesis constructs have been widely used, however non-union and implant failures are not uncommon. Recent literature advocates for the liberal use of supplemental medial plating to augment lateral locked constructs. However, there is a lack of proprietary medial plate options, with some authors supporting the use of repurposing expensive anatomic pre-contoured plates. The aim of this study was to investigate the feasibility of an effective, readily available medial implant option.

METHODS

A retrospective analysis from January 2014 to August 2023 was performed on DFF requiring revision open reduction internal fixation (rORIF) with supplemental medial plating with a Large Fragment Locking Compression Plate (LCP) T-Plate via a medial sub-vastus approach. The T-plate was contoured and placed superior to the medial condyle. A combination of 4.5 mm cortical, 5 mm locking and/or 6.5 mm cancellous screws were used, with oblique screw trajectories towards the distal lateral cortex of the lateral condyle. The primary outcome was union rate.

RESULTS

This technique was utilised on fifteen patients. The mean age was 55±15 (range 23-81); 73 % of cases were male and the median follow-up was 61 weeks (IQR 49-87). The two most common fracture patterns were AO/OTA 33-C3 (n = 5) and 33-A3 (n = 4), and three patients had open fractures. The union rate was 93 % (14/15), with a median time to union of 29 weeks (IQR 18-49). There were two complications: a deep infection requiring two debridements and locally eluding antibiotic insertion, and a prominent screw requiring removal; both patients achieved union. The median range of motion was 0° (IQR 0-5) of extension and 100° (IQR 90-120) of flexion.

CONCLUSION

Supplemental medial plating of DFF with a Large Fragment LCP T-Plate is a feasible, safe, and economical option for rORIF. Further validation on a larger scale is warranted, along with considerations to developing a specific implant in line with these principles.

Early weight bearing versus late weight bearing after intramedullary nailing for distal femoral fracture (AO/OTA 33) in elderly patients: A multicenter propensity-matched study

BACKGROUND

This study aimed to assess differences in implant failure and bone union rates, amount of change in alignment of lower extremities, and walking ability between early weight-bearing (EWB) and late weight-bearing (LWB) groups following retrograde intramedullary nailing (RIMN) for distal femoral fracture (AO/OTA 33) (DFF) at multiple centers using propensity score matching.

METHODS

The data of 213 patients who underwent RIMN from 2012 to 2019 in multiple tertiary hospitals were extracted from our database. Cases with the following factors were excluded: age <60, open fracture, AO/OTA-type 33-C3 fracture, preoperative New Mobility Score (NMS) < 3, postoperative follow-up <3 months, and unknown weight-bearing start time. Eighty-four patients were divided into the EWB and LWB groups. EWB group patients were encouraged to perform partial weight-bearing walking at ≤4 weeks after surgery. LWB group patients were not allowed weight bearing for >4 weeks after surgery. After propensity score matching was applied, 26 cases remained in each group.

RESULTS

There were no cases of nail failure in either the EWB group or LWB group (P = 1). Screw failure occurred in 0 cases in the EWB group and in 1 case (4.5%) in the LWB group (P = 1.0). Non-union occurred in 5 patients (19.2%) in the EWB group and 4 patients (15.3%) in the LWB group (P = 1). The mean amount of change in lower extremities alignment did not differ between the two groups. The median Knee Society Score was 95.5 (59-100) vs. 93 (72-100) points (P = 0.39). The median NMS was 7 (0-9) vs. 7 (4-9) points (P = 0.82).

CONCLUSIONS

There were no significant intergroup differences in the rates of implant failure, bone union at one year after surgery, amount of change in lower extremities alignment, or walking ability. We suggest that early weight bearing after RIMN for DFF may not be harmful in elderly people.

Changes in tibial cortical dimensions and density associated with long-term locking plate fixation in goats

PURPOSE

Cortical porosis, secondary to either vascular injury or stress-shielding, is a comorbidity of fracture fixation using compression bone plating. Locking plate constructs have unique mechanics of load transmission and lack of reliance on contact pressures for fixation stability, so secondary cortical porosis adjacent to the plate has not been widely investigated. Therefore, this study aimed to assess the effects of long-term locking plate fixation on cortical dimensions and density in a caprine tibial segmental ostectomy model.

METHODS

Data was acquired from a population of goats enrolled in ongoing orthopedic research which utilized locking plate fixation of 2 cm tibial diaphyseal segmental defects to evaluate bone healing over periods of 3, 6, 9, and 12 months. Quantitative data included tibial cortical width measurements and three-dimensionally reconstructed slab density measurements, both assessed using computed tomographic examinations performed at the time of plate removal. Additional surgical and demographic variables were analyzed for effect on cortical widths and density, and all cis-cortex measurements were compared to both the trans-cortex and to the contralateral limbs.

RESULTS

The tibial cis-cortex was significantly wider and more irregular than the trans-cortex at the same level. This width asymmetry differed in both magnitude and direction from the contralateral limb. The bone underlying the plate was significantly less dense than the trans-cortex, and this cortical density difference was significantly greater than that of the contralateral limb. These cortical changes were independent of both duration of fixation and degree of ostectomy bone healing.

CONCLUSIONS

This study provides evidence that cortical bone loss consistent with cortical porosity is a comorbidity of locking plate fixation in a caprine tibial ostectomy model. Further research is necessary to identify risk factors for locking-plate-associated bone loss and to inform clinical decisions in cases necessitating long-term locking plate fixation.

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.

Nail Plate Combination Fixation Versus Lateral Locked Plating for Distal Femur Fractures: A Multicenter Experience

OBJECTIVES

To (1) report on clinical, radiographic, and functional outcomes after nail-plate fixation (NPF) of distal femur fractures and (2) compare outcomes after NPF with a propensity matched cohort of fractures treated with single precontoured lateral locking plates.

DESIGN

Multicenter retrospective cohort study.

SETTING

Ten Level 1 trauma centers.

PATIENTS/PARTICIPANTS

Patients with OTA/AO 33A or 33C fractures.

INTERVENTION

Fixation with (1) retrograde intramedullary nail combined with lateral locking plate (n = 33) or (2) single precontoured lateral locking plate alone (n = 867).

MAIN OUTCOME MEASUREMENTS

The main outcomes of interest were all-cause unplanned reoperation and presence of varus collapse at final follow-up.

RESULTS

One nail-plate patient underwent unplanned reoperation excluding infection and 2 underwent reoperation for infection at an average of 57 weeks after surgery. No nail-plate patients required unplanned reoperation to promote union and none exhibited varus collapse. More than 90% were ambulatory with no or minimal pain at final follow-up. In comparison, 7 of the 30 matched lateral locked plating patients underwent all-cause unplanned reoperation excluding infection (23% vs. 3%, P = 0.023), and an additional 3 lateral locked plating patients were found to have varus collapse on final radiographs (10% vs. 0%, P = 0.069).

CONCLUSIONS

Despite a high proportion of high-energy, open, and comminuted fractures, no NPF patients underwent unplanned reoperation to promote union or demonstrated varus collapse. Propensity score matched analysis revealed significantly lower rates of nonunion for NPF compared with lateral locked plating alone. Larger studies are needed to identify which distal femur fracture patients would most benefit from NPF.

LEVEL OF EVIDENCE

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

Timing of Complications Following Surgery for Distal Femur Fractures in Older Adults

Introduction

The purpose of this study was to identify the timing and nature of complications associated with distal femur fracture surgery in patients aged 65 and older using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database.

Methods

The ACS NSQIP database was queried for adults aged 65 and older who received surgical treatment for a distal femur fracture between 01 January 2015 and 31 December 2021. Cox regression models and risk tables adjusted for baseline clinical characteristics were created for 14 complications (Superficial Surgical Site Infection (SSI), Deep SSI, Organ/Space SSI, Pneumonia, Pulmonary Embolism (PE), Deep Venous Thrombosis (DVT), Urinary Tract Infection (UTI), Stroke/Cerebrovascular accident (CVA), Myocardial Infarction (MI), Renal Failure, Cardiac Arrest (CA), Re-operation, Sepsis, and Death within 30 days of surgery). Model summaries were used to identify significant variables with a Bonferroni correction applied.

Results

A total of 3956 adults met inclusion criteria and were included in analysis. The most common complications were UTI (5.2%), death (4.1%), and pneumonia (3.4%). Complications typically occurred within 14 days after surgery, except for SSI, which occurred between post-op days 11 and 24.

Conclusions

Distal femur fractures are a substantial source of morbidity and mortality in the older adult population. Our findings underscore the need for comprehensive preoperative risk assessment and patient management strategies to mitigate the impact of identified risk factors in this vulnerable population.

Prediction of fracture nonunion leading to secondary surgery in patients with distal femur fractures

Aims

Several previously identified patient-, injury-, and treatment-related factors are associated with the development of nonunion in distal femur fractures. However, the predictive value of these factors is not well defined. We aimed to assess the predictive ability of previously identified risk factors in the development of nonunion leading to secondary surgery in distal femur fractures.

Methods

We conducted a retrospective cohort study of adult patients with traumatic distal femur fracture treated with lateral locking plate between 2009 and 2018. The patients who underwent secondary surgery due to fracture healing problem or plate failure were considered having nonunion. Background knowledge of risk factors of distal femur fracture nonunion based on previous literature was used to form an initial set of variables. A logistic regression model was used with previously identified patient- and injury-related variables (age, sex, BMI, diabetes, smoking, periprosthetic fracture, open fracture, trauma energy, fracture zone length, fracture comminution, medial side comminution) in the first analysis and with treatment-related variables (different surgeon-controlled factors, e.g. plate length, screw placement, and proximal fixation) in the second analysis to predict the nonunion leading to secondary surgery in distal femur fractures.

Results

We were able to include 299 fractures in 291 patients. Altogether, 31/299 fractures (10%) developed nonunion. In the first analysis, pseudo-R2 was 0.27 and area under the receiver operating characteristic curve (AUC) was 0.81. BMI was the most important variable in the prediction. In the second analysis, pseudo-R2 was 0.06 and AUC was 0.67. Plate length was the most important variable in the prediction.

Conclusion

The model including patient- and injury-related factors had moderate fit and predictive ability in the prediction of distal femur fracture nonunion leading to secondary surgery. BMI was the most important variable in prediction of nonunion. Surgeon-controlled factors had a minor role in prediction of nonunion.

Resistant distal femoral nonunion treated with combined nail/plate construct and reamer-irrigator-aspirator technique

OBJECTIVE

This study was performed to evaluate the effectiveness of intramedullary nailing and a lateral locking plate combined with the reamer-irrigator-aspirator (RIA) bone grafting technique for resistant distal femoral nonunion.

METHODS

This retrospective observational study was performed from January 2018 to December 2021 and involved five patients who presented with resistant distal femoral nonunion despite undergoing several surgeries. They were treated with intramedullary nailing and a lateral locking plate combined with the RIA bone grafting technique. Postoperative follow-up was performed to observe the healing time, and functional outcomes were evaluated using the Lower Extremity Functional Scale (LEFS).

RESULTS

After the patients had been monitored for a mean of 17.9 months, complete bone healing was observed in every patient (mean healing time of 4.8 months). Postoperative wound failure in an older patient was successfully treated with resuturing and nutritional assistance. At the last follow-up, the mean LEFS score was 71.2/80 and the mean knee flexion was 109 degrees.

CONCLUSIONS

Our study demonstrates that combining intramedullary nailing and a lateral locking plate with the RIA bone grafting technique enhances biological properties, provides good structural support, and achieves good union and functional results in the management of resistant nonunion of the distal femur.

Distal femur fractures management and evolution in the last century

PURPOSE

The purpose of this historical review is to illustrate the progression and evolution of treatment for distal femur fractures.

METHODS

Scientific literature was searched for descriptions of treatment for distal femur fractures to provide an in-depth overview of the topic, with emphasis on the evolution of surgical constructs used to treat these fractures.

RESULTS

Prior to the 1950s, distal femur fractures were treated nonoperatively, resulting in considerable morbidity, limb deformity, and limited function. As principles of surgical intervention for fractures emerged in the 1950s, surgeons developed conventional straight plates to better stabilize distal femur fractures. Angle blade plates and dynamic condylar screws emerged out of this scaffolding to prevent post-treatment varus collapse. Meanwhile, intramedullary nails, and later, in the 1990s, locking screws, were introduced to minimize soft tissue disruption. Treatment failure led to the development of locking compression plates with the advantage of accommodating either locking or nonlocking screws. Despite this advancement, the rare but significant incidence of nonunion has not been eliminated, leading to the recognition of the biomechanical environment as important for prevention and the development of active plating techniques.

CONCLUSION

Emphasis for the surgical treatment of distal femur fractures has incrementally progressed over time, with initial focus on complete stabilization of the fracture while the biological environment surrounding the fracture was ignored. Techniques slowly evolved to minimize soft tissue disruption, allow more ease of implant placement at the fracture site, and attend to the systemic health of the patient, while simultaneously ensuring appropriate fracture fixation. Through this dynamic process, the desired results of complete fracture healing and maximization of functional outcomes have emerged.

In vitro analysis and in vivo assessment of fracture complications associated with use of locking plate constructs for stabilization of caprine tibial segmental defects

PURPOSE

Locking plate fixation of caprine tibial segmental defects is widely utilized for translational modeling of human osteopathology, and it is a useful research model in tissue engineering and orthopedic biomaterials research due to its inherent stability while maintaining unobstructed visualization of the gap defect and associated healing. However, research regarding surgical technique and long-term complications associated with this fixation method are lacking. The goal of this study was to assess the effects of surgeon-selected factors including locking plate length, plate positioning, and relative extent of tibial coverage on fixation failure, in the form of postoperative fracture.

METHODS

In vitro, the effect of plate length was evaluated using single cycle compressive load to failure mechanical testing of locking plate fixations of caprine tibial gap defects. In vivo, effects of plate length, positioning, and relative tibial coverage were evaluated using data from a population of goats enrolled in ongoing orthopedic research which utilized locking plate fixation of 2 cm tibial diaphyseal segmental defects to evaluate bone healing over 3, 6, 9, and 12 months.

RESULTS

In vitro, no significant differences in maximum compressive load or total strain were noted between fixations using 14 cm locking plates and 18 cm locking plates. In vivo, both plate length and tibial coverage ratio were significantly associated with postoperative fixation failure. The incidence of any cortical fracture in goats stabilized with a 14 cm plate was 57%, as compared with 3% in goats stabilized with an 18 cm plate. Craniocaudal and mediolateral angular positioning variables were not significantly associated with fixation failure. Decreasing distance between the gap defect and the proximal screw of the distal bone segment was associated with increased incidence of fracture, suggesting an effect on proximodistal positioning on overall fixation stability.

CONCLUSIONS

This study emphasizes the differences between in vitro modeling and in vivo application of surgical fixation methods, and, based on the in vivo results, maximization of plate-to-tibia coverage is recommended when using locking plate fixation of the goat tibial segmental defect as a model in orthopedic research.

Predictors of Deep Infection After Distal Femur Fracture: A Multicenter Study

OBJECTIVES

To identify potentially modifiable risk factors for deep surgical site infection after distal femur fracture.

DESIGN

Multicenter retrospective cohort study.

SETTING

Ten Level-I trauma centers.

PATIENTS/PARTICIPANTS

Patients with OTA/AO 33A or C distal femur fractures (n = 1107).

INTERVENTION

Surgical fixation of distal femur fracture.

MAIN OUTCOME MEASUREMENT

The outcome of interest was deep surgical site infection.

RESULTS

There was a 7% rate (79/1107) of deep surgical site infection. In the multivariate analysis, predictive factors included alcohol abuse [odds ratio (OR) = 2.36; 95% confidence interval (CI), 1.17-4.46; P = 0.01], intra-articular injury (OR = 1.73; 95% CI, 1.01-3.00; P = 0.05), vascular injury (OR = 3.90; 95% CI, 1.63-8.61; P < 0.01), the use of topical antibiotics (OR = 0.50; 95% CI, 0.25-0.92; P = 0.03), and the duration of the surgery (OR = 1.15 per hour; 95% CI, 1.01-1.30; P = 0.04). There was a nonsignificant trend toward an association between infection and type III open fracture (OR = 1.73; 95% CI, 0.94-3.13; P = 0.07) and lateral approach (OR = 1.60; 95% CI, 0.95-2.69; P = 0.07). The most frequently cultured organisms were methicillin-resistant Staphylococcus aureus (22%), methicillin-sensitive Staphylococcus aureus (20%), and Enterobacter cloacae (11%).

CONCLUSIONS

Seven percent of distal femur fractures developed deep surgical site infections. Alcohol abuse, intra-articular fracture, vascular injury, and increased surgical duration were risk factors, while the use of topical antibiotics was protective.

LEVEL OF EVIDENCE

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

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.

Risk Factors for Reoperation to Promote Union in 1111 Distal Femur Fractures

OBJECTIVES

To identify modifiable and nonmodifiable risk factors for reoperation to promote union after distal femur fracture.

DESIGN

Multicenter retrospective cohort study.

SETTING

Ten Level-I trauma centers.

PATIENTS/PARTICIPANTS

Patients with OTA/AO 33A or C distal femur fractures (n = 1111).

INTERVENTION

Surgical fixation of distal femur fracture. Fixation constructs were classified as lateral plate, dual plate, nail, or nail plate combination.

MAIN OUTCOME MEASUREMENTS

The outcome of interest was unplanned reoperation to promote union.

RESULTS

There was an 11% (121/1111) rate of unplanned reoperation to promote union. In the multivariate analysis, predictive factors included body mass index [odds ratio (OR) = 1.18; 95% confidence interval (CI), 1.06-1.32; P < 0.01], intra-articular fracture (OR = 1.57; 95% CI, 1.01-2.45; P = 0.04), type III open injury (OR = 2.29; 95% CI, 1.41-3.72; P < 0.01), the presence of medial comminution (OR = 1.85; 95% CI, 1.14-3.06; P = 0.01), and medial translation on postoperative radiographs (OR = 1.23 per one 10th of condylar width; 95% CI, 1.01-1.48; P = 0.03). Construct type was not significantly predictive.

CONCLUSIONS

Eleven percent of distal femur fractures underwent unplanned reoperation to promote union. Body mass index, intra-articular fracture, type III open injury, medial comminution, and medial translation on postoperative radiographs were predictive factors. Construct type was not associated with unplanned reoperation; however, this conclusion was limited by small numbers in the dual plate and nail plate groups.

LEVEL OF EVIDENCE

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

Outcome Evaluation of Distal Femoral Fractures Following Surgical Management: A Retrospective Cohort Study

BACKGROUND

Distal femur fractures are challenging in surgical management as the outcome is crucial for restoring the biomechanical stability and longitudinal axis of the leg and function of the knee joint.

METHODS

A retrospective review of all distal femoral fractures treated in a level I trauma center over a decade was performed. The radiographs were reviewed for fracture entity, osseous healing, implant failure, mechanical axis, and degenerative joint changes. Clinical outcome was reviewed regarding postoperative complications and postoperative range of motion of the knee joint.

RESULTS

130 patients who were managed with screw fixation (n = 35), plating systems (n = 92) or intramedullary nailing systems (n = 3) remained for evaluation. Mean follow up was 26 months. Clinical outcome was significantly better for flexion degrees following screw fixation (p = 0.009). Delayed fracture union (p = 0.002) or non-union (p = 0.006) rates were significantly higher in plate osteosynthesis. Mild pathologic deformity for varus and valgus collapse was found following plate osteosynthesis.

CONCLUSIONS

Screw fixation shows fewer postoperative complications than plate fixation and is favored for extra and partial intraarticular distal femur fractures. Plating constructs remain the superior fixation method in complex distal femur fractures but are associated with higher rates of non-union and leg axis deviation.

Influence of plate size and screw distribution on the biomechanical behaviour of osteosynthesis by means of lateral plates in femoral fractures

Distal femoral fractures are fractures associated with high rates of morbidity and mortality, affecting to three different groups of individuals: younger people suffering high-energy trauma, elderly people with fragile bones and people with periprosthetic fractures around previous total knee arthroplasty. They have been classically treated with conventional plates and intramedullary nails and more recently with locked plates that have increased their indications to more types of fractures. The main objective of the present work is the biomechanical study, by means of finite element simulation, of the stability achieved in the osteosynthesis of femoral fractures in zones 4 and 5 of Wiss, by using locked plates with different plate lengths and different screw configurations, and analysing the effect of screw proximity to the fracture site. A three dimensional (3D) finite element model of the femur from 55-year-old male donor was developed, and then a stability analysis was performed for the fixation provided by Osteosynthesis System LOQTEC® Lateral Distal Femur Plate in two different fracture zones corresponding to the zones 4 and 5 according to the Wiss fracture classification. The study was focused on the immediately post-operative stage, without any biological healing process. The obtained results show that more stable osteosyntheses were obtained by using shorter plates. In the cases of longer plates, it results more convenient disposing screws in a way that the upper ones are closer to fracture site. The obtained results can support surgeons to understand the biomechanics of fracture stability, and then to guide them towards the more appropriate osteosynthesis depending on the fracture type and location.

Open Reduction Internal Fixation Versus Distal Femoral Replacement (DFR) for Treatment of OTA/AO 33C Fractures in the Elderly: A Review of Functional Outcomes and Cost Analysis

OBJECTIVES

To determine the economic cost associated with the treatment of OTA/AO 33C fractures in patients older than 65 years of age using open reduction internal fixation (ORIF) or DFR and to assess the perioperative outcomes of elderly patients treated surgically following OTA/AO 33C fractures.

DESIGN

Retrospective cohort over a 10-year period.

SETTING

A single level-1 trauma center.

PARTICIPANTS AND INTERVENTION

Thirty-nine patients 65 or older with OTA/AO 33C fractures who underwent treatment with ORIF (n = 27) or DFR (n = 12) were included.

MAIN OUTCOME MEASUREMENTS

Direct cost associated with surgical treatment along with LOS, functional outcomes, patient-reported outcomes, and all-cause reoperation.

RESULTS

Index procedure costs were as follows: DFR: $ 61,259 vs. ORIF: $44,490 (P = 0.056). Five (20%) ORIF patients required revision versus one (8%) in the DFR group. Total cost when including reoperation resulted in DFR being $14,805 more costly, which was not significant. Hospital LOS was similar between groups; however, convalescent LOS was longer in ORIF patients (43.2 vs. 23.1 days, P = 0.02).

CONCLUSION

This study demonstrates that there is no significant difference in overall cost between ORIF and DFR when all costs are considered. A larger portion of DFR patients were able to mobilize postoperatively, with subacute length of stay being longer in ORIF patients. A multicenter trial is warranted to determine optimal treatment for this complex problem.

LEVEL OF EVIDENCE

Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Analysis of 101 Mechanical Failures in Distal Femur Fractures Treated with 3 Generations of Precontoured Locking Plates

OBJECTIVES

To evaluate mechanical treatment failure in a large patient cohort sustaining a distal femur fracture treated with a distal femoral locking plate (DFLP).

DESIGN

This retrospective case-control series evaluated mechanical treatment failures of DFLPs.

SETTING

The study was conducted at 8 Level I trauma centers from 2010 to 2017.

PATIENTS AND PARTICIPANTS

One hundred one patients sustaining OTA/AO 33-A and C distal femur fractures were treated with DFLPs that experienced mechanical failure.

INTERVENTION

The intervention included the treatment of a distal femur fracture with a DFLP, affected by mechanical failure (implant failure by loosening or breakage).

MAIN OUTCOME MEASURE

The main outcome measures included injury and DFLP details; modes and timing of failure were studied.

RESULTS

One hundred forty-six nonunions were found overall (13.4%) including 101 mechanical failures (9.3%). Failures occurred in different manners, locations, and times depending on the DFLPs. For example, 33 of 101 stainless steel (SS) plates (33%) failed by bending or breaking in the working length, whereas no Ti plates failed here ( P < 0.05). Eleven of 12 failures with titanium-Less Invasive Stabilization System (92%) occurred by lost shaft fixation, mostly by the loosening of unicortical screws (91%). Sixteen of 44 variable -angled-LCP failures (36%) occurred at the distal plate-screw junction, whereas only 5 of 61 other DFLPs (8%) failed this way ( P < 0.05). Distal failures occurred on average at 23.7 weeks compared with others that occurred at 38.4 weeks ( P < 0.05). Variable -angled-LCP distal screw-plate junction failures occurred earlier (mean 21.4 weeks).

CONCLUSION

Nonunion and mechanical failure occurred in 14% and 9% of patients, respectively, in this large series of distal femur fracture treated with a DFLP. The mode, location, presence of a prosthesis, and timing of failure varied depending on the characteristics of DFLP. This information should be used to optimize implant usage and design to prolong the period of stable fixation before potential implant failures occur in patients with a prolonged time to union.

LEVEL OF EVIDENCE

Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

[Related factors of revision of distal femoral fractures treated with lateral locking plate]

OBJECTIVE

To analyze the factors related to the need for revision surgery due to nonunion or internal fixation failure after the treatment of distal femoral fracture with lateral locking plate (LLP).

METHODS

Retrospective analysis was made of the clinical data of 130 cases with distal femoral fracture treated in our hospital from March 2005 to March 2019. SPSS 17.0 software (univariate analysis and Logistic regression analysis) was used to analyze the general condition [gender, age, body mass index (BMI), comorbidities, smoking history], injury related factors (energy of injury, open or closed injury, AO/OTA classification of fracture, fracture area distribution), operation related factors (operation time, reduction quality, postoperative infection) and construct characteristics of internal fixation.

RESULTS

Twelve of 130 patients who were included in the study underwent revisional surgery, with a revision rate 9.2%. Univariate analysis showed that there were significant differences in age, BMI, AO/OTA classification, fracture area distribution, operation time, reduction quality, length of plate/fracture area, length of plate/fracture area above condylar between the two groups (P < 0.05). Logistic regression analysis showed that AO/OTA classification (A3), supracondylar involved fracture, operation time, reduction quality and the length of the plate/fracture area above the condylar were the possible related factors (P < 0.05). Destruction of the medial support ability of the femur in comminuted type A3 fracture, supra-condylar cortex area fracture involvement, increase of the bending stress of the LLP due to poor fracture reduction quality, damage of the blood supply of fracture end due to long-time operation, and stress concentration caused by insufficient length of plate might be risk factors of revisional operation after the treatment of distal femoral fracture with LLP. For the patients who needed revision after LLP treatment, additional use of medial minimally invasive plate fixation and autologous bone transplantation, change to intramedullary nail fixation were commonly used clinical treatment strategies.

CONCLUSION

AO/OTA classification (A3), supracondylar involved fracture, long operation time, poor reduction quality and the length of the plate/fracture area above the condylar were the possible predictive factors of the revision in distal femoral fractures treated with lateral locking plate. The appropriate application of the locking plate and operation strategy are the key to reduce the revision rate in distal femoral fractures.

DISTAL FEMORAL FRACTURES FROM HIGH-ENERGY TRAUMA: A RETROSPECTIVE REVIEW OF COMPLICATION RATE AND RISK FACTORS

Objective

Determine complications' incidence and risk factors in high-energy distal femur fractures fixed with a lateral locked plate.

Methods

Forty-seven patients were included; 87.2% were male, and the average age was 38.9. The main radiographic parameters collected were distal lateral femoral angle (DFA), distal posterior femoral angle (DPLF), comminution length, plate length, screw working length, bone loss, and medial contact after reduction and plate-bone contact, location of callus formation, and implant failure. The complications recorded were nonunion, implant failure, and infection.

Results

Complex C2 and C3 fractures accounted for 85.1% of cases. Open fractures accounted for 63.8% of cases. The mean AFDL and AFDP were 79.8 4.0 and 79.3 6.0, respectively. The average total proximal and distal working lengths were 133.3 42.7, 60.4 33.4, and 29.5 21.8 mm, respectively. The infection rate was 29.8%, and the only risk factor was open fracture (p = 0.005). The nonunion rate was 19.1%, with longer working length (p = 0.035) and higher PDFA (p = 0.001) as risk factors. The site of callus formation also influenced pseudoarthrosis (p = 0.034).

Conclusion

High-energy distal femoral fractures have a higher incidence of pseudoarthrosis and infection. Nonunion has greater working length, greater AFDL, and absence of callus formation on the medial and posterior sides as risk factors. The risk factor for infection was an open fracture. Level of Evidence III; Retrospective Cohort Study .

The Management of Aseptic Non-unions of Distal Femur Fractures with Anatomical Lateral Locking Plates

Background

Distal femoral non-unions are challenging, and frequently associated with short distal fragments, poor bone stock, and with issues from previous implants.

Materials and methods

A retrospective study of 31 patients admitted with distal femoral non-unions treated using anatomical lateral locking plates. Non-union scores were used. The Knee Society and Neer's scores were used for the comparison of results. The mean follow-up was 39.5 months (from 24 months to 60 months).

Results

Stable union was accomplished in all. There was a significant improvement in the average Neer's score (24 preoperative to 82 post-operatively at final follow-up), the Part 1 Knee Society score from an average of 46 preoperatively to 84 post-operatively, and Part 2 Knee Society score from 36 preoperatively to 80 post-operatively.

Conclusion

Optimal stability, good compression at the non-union site (either by lag screws or a compression device or both), maintaining the axial alignment strictly, freshening of bone ends, using an adequate amount of cortico-cancellous bone graft, respecting the biology along with the correct choice of the implant (including the size) are essential to achieve union at the fracture site.

Clinical significance

Paying attention to the basic principles of management, good contact, stability and maintaining biology is essential in the treatment of non-union.

How to cite this article

Mukhopadhaya J, Ranjan R, Sinha AK, et al. The Management of Aseptic Non-unions of Distal Femur Fractures with Anatomical Lateral Locking Plates. Strategies Trauma Limb Reconstr 2022;17(3):137-143.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Comminuted periprosthetic distal femoral fractures have greater postoperative extension malalignment

INTRODUCTION

Comminution is a significant aspect of periprosthetic distal femoral fracture characterization and may influence post-surgical outcomes. Existing classification systems that guide treatment decisions do not take into account comminution and current literature is unclear on which surgical approach is optimal. We hypothesize that fractures with comminution will have poorer quality post-reduction alignment, especially with a lateral approach.

MATERIALS AND METHODS

37 study patients were identified with billing codes designating a distal femoral periprosthetic fracture. A retrospective chart review was performed to categorize fractures by absence or presence of comminution and medial parapatellar versus lateral surgical approach. These patients underwent an imaging evaluation for the primary outcome of reduction quality including the anatomic lateral distal femoral angle (LDFA) and the posterior distal femoral angle (PDFA). Differences in radiographic outcomes were analyzed with Wilcoxon/Kruskal-Wallis tests, and analysis by approach was through Fisher's exact test.

RESULTS

Patients with comminuted fractures had significantly greater extension of the fragment (PDFA = 95.4° vs 90.0°, p = 0.018) and similar coronal alignment (LDFA = 85.3° vs 86.3°, p = 0.83) of the knee compared to non-comminuted fractures after surgical reduction. This difference was more prominent amongst those treated with a lateral approach (PDFA = 96.1° vs 89.4°, p = 0.032) than with a medial approach (PDFA = 93.7° vs 91.5°, p = 0.41) (Table 1).

DISCUSSION

Current classification systems and treatment guidelines for periprosthetic distal femoral fractures do not adequately address several issues that may influence treatment outcomes, especially comminution. Comminuted fractures had greater post-reduction extension malalignment, falling outside the recommended PDFA range of 87-90°, especially with a lateral approach. Consideration should be given to surgical approach and techniques to reduce excessive extension when treating comminuted periprosthetic distal femoral fractures.

Primary fibular grafting combined with double plating in distal femur fractures in elderly patients

PURPOSE

To report functional and radiological outcomes of using primary fibular graft together with double plating in distal femoral fractures in the elderly.

METHODS

A retrospective study on 30 elderly patients with comminuted distal femoral fractures managed by primary fibular grafting and double plating through an anterior midline approach has been conducted. Only isolated distal femoral fractures type 33-A3, 33-C2, and 33-C3 were included. The patient's mean age was 75.3 years. Evaluation included operative time, blood loss, time to union, knee range of motion, Sanders scoring, and presence of complications.

RESULTS

The average follow-up period was 26.6 months. Mean intraoperative blood loss was 401 ml, and mean operative time was 216 min. All patients had a knee range of motion (90-120°) during follow-up. Time for union ranged from 16 to 23 weeks with a mean of 18.4 weeks, with no cases of non-union. A total of 22 patients (73.3%) showed excellent functional outcomes, and the remaining eight (26.7%) showed good functional outcomes according to the Sanders scoring system. Only two cases (6.6%) had superficial wound infections managed conservatively. No post-operative deformity, loss of reduction, or implant failure was observed until the end of follow-up period.

CONCLUSION

Primary fibular grafting combined with double plating of comminuted distal femur fractures in patients above 70 years is an effective technique with higher rates of union and lower re-operation rates compared to other fixation modalities.

Low body mass index is a risk factor for increased post-operative mortality and poor functional improvement in distal femur fractures among patients aged over 65: A multicentre (TRON) study

BACKGROUND

Distal femur fractures have been reported to have a mortality rate comparable to hip fractures, but the risk is still unknown. Recent studies have reported that low body mass index (BMI) is a risk factor for mortality in the elderly. We investigated the efficacy of low BMI for predicting the risk of mortality in distal femur fractures in patients aged over 65 within 18 months after injury and its impact on postoperative clinical outcomes and mortality.

METHODS

Data from patients followed for more than six months were obtained from our trauma research group's database. We investigated risk factors for increased mortality using Cox proportional hazards models. We divided the analysed cases into low (<18.5 kg/m²) and high (>18.5 kg/m²) BMI groups. We adjusted the background characteristics of the groups by patient matching, and evaluated the postoperative mortality, complication rate, and knee society score (KSS).

RESULTS

We identified 216 patients, including 58 (26.9%) with low BMI values. Low BMI was an independent risk factor for mortality in all models (Hazard Ratio: 2.9, p = 0.011). The overall survival rate of the low BMI group at 18 months was significantly lower than that of the high BMI group (70.7% vs. 89.1%; p = 0.003). The complication rates of the low BMI and high BMI groups were not significantly different (33.3% vs. 22.2%; p = 0.283). The mean KSS values at 3, 6, and 12 months in the low BMI group was significantly worse than that in the high BMI group (78.7 ± 16.2 vs. 84.8 ± 13.1; p = 0.035, 82.2 ± 16.9 vs. 89.7 ± 8.9; p = 0.005, 86.4 ± 13.0 vs. 91.4 ± 8.4; p = 0.020, respectively).

CONCLUSIONS

Our study indicated that low BMI was independent associated with increased mortality and impaired postoperative functional recovery in distal femur fractures of the elderly patients.

Immediate Full Weight-Bearing Versus Partial Weight-Bearing After Plate Fixation of Distal Femur Fractures in Elderly Patients. A Randomized Controlled Trial

Introduction

After surgery for distal femur fractures in elderly patients, weight-bearing is commonly restricted. Immediate non-restrictive weight-bearing might have beneficial effects. There are no randomized studies on the topic. The purpose of this study was to compare the functional outcome between immediate full weight-bearing (FWB) as tolerated and partial weight-bearing (PWB) during the first 8 weeks following plate fixation of distal femur fractures in elderly patients.

Methods

Patients aged 65 years or older with distal femur fractures of AO/OTA types 33 A2, A3, B1, B2, C1, and C2 were included. Exclusion criteria were impaired cognitive function, concomitant injuries, or inability to follow the postoperative regimen. Internal fixation was achieved with an anatomical lateral distal femur plate applied as a strictly bridge-plating construct. The primary outcome measure was the function index of the short musculoskeletal functional assessment (SMFA) after 52 weeks from injury.

Results

Thirty-two patients were randomized to FWB (n = 11) or PWB (n = 21). After 16 and 52 weeks, there were no differences in the mean SMFA function index between FWB and PWB (36 vs 43, P = .42 and 52 vs 40, P = .18, respectively) nor in the mean EuroQol 5-dimension index or range of motion (ROM). Overall, the SMFA function index was higher at 52 weeks compared with before injury (44 vs 30, P = .001) as was the mean bothersome index (37 vs 21, P = .011). There was no clear difference in the occurrence of adverse events between the treatment groups.

Conclusions

There were no differences in functional outcome, adverse events, or ROM between immediate FWB and PWB following plate fixation for a distal femur fracture in elderly patients. A distal femur fracture has a negative effect on the functional status of elderly patients that persists at least up to 1 year following injury.

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.

Modeling attachment and compressive loading of locking and non-locking plate fixation: a finite element investigation of a supracondylar femur fracture model

This study developed a finite element (FE) model of simulated locking plate fixation to examine the strain response following supracondylar femoral plate attachment and under compressive loading. An implicit FE model of a synthetic femur with a distal fracture gap stabilized with a lateral plate was evaluated following attachment and 500 N loading, considering locking and non-locking proximal screws configurations. Screw pre-tension values of 60 N for both distal and proximal non-locking screws yielded good agreement with plate experimental strain data in attached (unloaded) and loaded conditions. The results highlight the importance of pre-tensioning in modeling plate attachment using non-locking screws.

Fractures of the distal femur in elderly patients: retrospective analysis of a case series treated with single or double plate

Introduction

We evaluated the radiologic and clinical outcomes of a lateral incision single plate with and a single-incision double plating in elderly patients with osteoporotic distal femoral fractures.

Materials and methods

We performed a retrospective study of 82 cases of distal femoral fractures from May 2004 to June 2018. Group A consisted of 42 patients who underwent single-plate fixation. Group B consisted of 40 patients who underwent double-plate fixation. The mean patient age was 77 years (67–87 years) and 76 years (64–86 years) in groups A and B, respectively. All patients were evaluated for procedure duration, time to union, range of knee motion, Lysholm knee score, and presence of complications.

Results

The average procedure time was 81 min (66–92 min) and 110 min (95–120 min) in groups A and B, respectively (p = 0.33). One case in group B required bone grafting after 5 months. The average time to union was 14 weeks (9–19 weeks) and 12.2 weeks (8–19 weeks) (p = 0.63), and the mean range of knee motion was 105° (90–125°) and 110.7° (90°–130°) (p = 0.37) in groups A and B, respectively. There was no significant statistical difference between the two groups in the Lysholm knee score (p = 0.44) and knee society score (p = 0.53).

Conclusion

The clinical and radiological outcomes were similar in the 2 groups. In elderly patients, double plate fixation for distal femoral fractures is an useful method for several advantages such as adequate exposure, easy manipulation, anatomical reduction and stable fixation.

Analysis of Risk Factors for Non-union After Surgery for Limb Fractures: A Case-Control Study of 669 Subjects

Objective: The purpose of this study was to analyze the risk factors for limb fracture non-union in order to improve non-union prevention and early detection.

Methods: A total of 223 patients with non-union after surgery for limb fractures performed at our institution from January 2005 to June 2017 were included as the case group, while a computer-generated random list was created to select 446 patients with successful bone healing after surgery for limb fractures who were treated during the same period as the control group, thus achieving a ratio of 1:2. The medical records of these patients were reviewed retrospectively. Age, sex, body mass index, obesity, smoking, alcohol, diabetes, hypertension, osteoporosis, fracture type, multiple fractures, non-steroidal anti-inflammatory drugs (NSAIDs) use, delayed weight bearing, internal fixation failure, and infection data were analyzed and compared between the two groups. A multivariate logistic regression model was constructed to determine relevant factors associated with non-union.

Results: After comparison between two groups by univariate analysis and multivariate logistic regression, we found some risk factors associated that osteoporosis (odds ratio [OR] = 3.16, 95% confidence interval [CI]: 2.05–4.89, p < 0.001), open fracture (OR = 2.71, 95%CI: 1.72–4.27, p < 0.001), NSAIDs use (OR = 2.04, 95%CI: 1.24–3.37, p = 0.005), delayed weight bearing (OR = 1.72, 95%CI: 1.08–2.74, p = 0.023), failed internal fixation (OR = 5.93, 95%CI: 2.85–12.36, p < 0.001), and infection (OR = 6.77, 95%CI: 2.92–15.69, p < 0.001) were independent risk factors for non-union after surgery for limb fractures.

Conclusions: Osteoporosis, open fracture type, NSAIDs use, delayed weight bearing, failed internal fixation, and infection were found to be the main causes of bone non-union; clinicians should, therefore, take targeted measures to intervene in high-risk groups early.

Fracture, nonunion and postoperative infection risk in the smoking orthopaedic patient: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to analyse negative effects of smoking in orthopaedic and trauma patients.

A PubMed search was carried out for studies published until July 2020 regarding effects of smoking on fracture risk, nonunion, infection after orthopaedic surgery, and persisting nonunion after scaphoid nonunion surgery. Random effects models calculated for outcome parameters, and relative risks (RR) with 95% confidence intervals are provided. No adjustments for covariates were made. Heterogeneity was assessed with Higgins’ I2, publication bias with Harbord’s p (Hp), sensitivity analysis performed on funnel plots and quality of studies was analysed using the Newcastle-Ottawa Scale.

Of 3362 retrieved entries, 69 were included in the final analysis. Unadjusted RR for smokers to develop vertebral (six studies, seven entries; RR: 1.61; p = 0.008; I2 = 89.4%), hip (11 studies, 15 entries; RR: 1.28; p = 0.007; I2 = 84.1%), and other fractures (eight studies, 10 entries; RR: 1.75; p = 0.019; I2 = 89.3%) was significantly higher. Postoperative infection risk was generally higher for smokers (21 studies; RR: 2.20; p < 0.001; I2 = 58.9%), and remained upon subgroup analysis for elective spinal (two studies; RR: 4.38; p < 0.001; I2 = 0.0%) and fracture surgery (19 studies; RR: 2.10; p < 0.001; I2 = 58.5%). Nonunion risk after orthopaedic (eight studies; RR: 2.15; p < 0.001; I2 = 35.9%) and fracture surgery (11 studies; RR: 1.85; p < 0.001; I2 = 39.9%) was significantly higher for smokers, as was persisting nonunion risk after surgery for scaphoid nonunion (five studies; RR: 3.52; p < 0.001; I2 = 0.0%). Sensitivity analysis for each model reduced heterogeneity whilst maintaining significance (all I2 < 20.0%).

Smoking has a deleterious impact on fracture incidence, and (subsequent) development of nonunions and postoperative infections.

Cite this article: EFORT Open Rev 2021;6:1006-1019. DOI: 10.1302/2058-5241.6.210058

A systematic review of the use of titanium versus stainless steel implants for fracture fixation

Background:

Controversy exists regarding the use of titanium and stainless steel implants in fracture surgery. To our knowledge, no recent, comprehensive review on this topic has been reported.

Purpose:

To perform a systematic review of the evidence in the current literature comparing differences between titanium and stainless steel implants for fracture fixation.

Methods:

A systematic review of original research articles was performed through the PubMed database using PRISMA guidelines. Inclusion criteria were English-language studies comparing titanium and stainless steel implants in orthopaedic surgery, and outcome data were extracted.

Results:

The search returned 938 studies, with 37 studies meeting our criteria. There were 12 clinical research articles performed using human subjects, 11 animal studies, and 14 biomechanical studies. Clinical studies of the distal femur showed the stainless steel cohorts had significantly decreased callus formation and an increased odds radio (OR 6.3, 2.7-15.1; P < .001) of nonunion when compared with the titanium plate cohorts. In the distal radius, 3 clinical trials showed no implant failures in either group, and no difference in incidence of plate removal, or functional outcome. Three clinical studies showed a slightly increased odds ratio of locking screw breakage with stainless steel intramedullary nails compared with titanium intramedullary nails (OR 1.52, CI 1.1-2.13).

Conclusion:

Stainless steel implants have equal or superior biomechanical properties when compared with titanium implants. However, there is clinical evidence that titanium plates have a lower rate of failure and fewer complications than similar stainless steel implants in some situations. Although our review supports the use of titanium implants in these clinical scenarios, we emphasize that further prospective, comparative clinical studies are required before the conclusions can be made.

Infected Nonunion of the Distal Femur in the Elderly with Bone Loss: Case Report and Treatment Options

The management of infected nonunion associated with bone loss in long bones is both a time-consuming and challenging procedure for the orthopedic and trauma surgeon. In this paper, we present the case of a 75-year-old woman with infected nonunion of the distal femur associated with bone loss after plate osteosynthesis for a distal femur fracture. The patient was referred for nonunion of the distal femur after plate fixation (nonlocking "classic" plate) and was treated with a locking compression plate (LCP) and autologous cancellous bone transplant. During the follow-up, the patient was ambulatory without pain; however, the nonunion failed to heal, therefore, the induced membrane technique (Masquelet procedure) was performed in two stages, tissue samples were taken and revealed a bacterial infection (S. epidermidis), and antibiotic treatment was started. Due to infection, fracture healing was slowed, but did commence. Unfortunately, the LC plate failed before union occurred, the nonunion was treated with a femoral nail and blocking (Poller) screws, and the bony defect was filled with Ca-P cement. The patient was operated one last time for cement dislocation when not only the dislocated cement was removed but also the femoral nail dynamized. After one year after treatment completion, the fracture healed, and leg length discrepancy was 1.5 cm shorter on the left side. The patient experienced significant pain relief and can walk with the help of crutches. Our paper demonstrates the application of different techniques in fracture surgery as they are required can result in fracture healing even in very adverse circumstances.

Factors predicting failure of internal fixations of fractures of the lower limbs: a prospective cohort study

Background

We assessed predictive factors of patients with fractures of the lower extremities caused by trauma. We examined which factors are associated with an increased risk of failure. Furthermore, the predictive factors were set into context with other long-term outcomes, concrete pain and physical functioning.

Methods

We performed a prospective cohort study at a single level I trauma center. We enrolled patients with traumatic fractures of the lower extremities treated with internal fixation from April 2017 to July 2018. We evaluated the following predictive factors: age, gender, diabetes, smoking status, obesity, open fractures and peripheral arterial diseases. The primary outcome was time to failure (nonunion, implant failure or reposition). Secondary outcomes were pain and physical functioning measured 6 months after initial surgery. For the analysis of the primary outcome, we used a stratified (according fracture location) Cox proportional hazard regression model.

Results

We included 204 patients. Overall, we observed failure in 33 patients (16.2 %). Most of the failures occurred within the first 3 months. Obesity and open fractures were associated with an increased risk of failure and decreased physical functioning. None of the predictors showed an association with pain. Age, female gender and smoking of more than ≥ 10 package years increased failure risk numerically but statistical uncertainty was high.

Conclusions

We found that obesity and open fractures were strongly associated with an increased risk of failure. These predictors seem promising candidates to be included in a risk prediction model and can be considered as a good start for clinical decision making across different types of fractures at the lower limbs. However, large heterogeneity regarding the other analyzed predictors suggests that “simple” models might not be adequate for a precise personalized risk estimation and that computer-based models incorporating a variety of detailed information (e.g. pattern of injury, x-ray and clinical data) and their interrelation may be required to significantly increase prediction precision.

Trial registration

NCT03091114.

Knee mega-prosthesis in the management of complex knee fracture of the elderly : a case series and review of the literature

The management of complicated distal femur fractures (DFF) of the elderly continues to pose a challenge. Knee mega-prosthesis are mostly used for Total knee arthroplasty revision and tumor resection surgery but they can be used for the treatment of complex knee fractures. The purpose of the present study is to examine the short- to mid- term outcomes of their use for complex DFF of the elderly. We retrospectively identified 4 patients with DFF AO33C3 on osteoporotic bone treated by total knee arthroplasty from September 2015 to October 2019. The average age at the time of the surgery was 79,5 years (range, 69 to 95 years). All patients were females and underwent a total knee replacement by one senior surgeon, with the OSS TM Orthopaedic Salvage System (Zimmer Biomet, Warsaw, Indiana, USA). Outcome measures included clinical outcome scores, radiological analyses, reoperation rate and complications. At an average follow-up of 2,3 years (range, 0,6 to 4,2 years), the average Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) was 17,25 (range, 7 to 37), the average Oxford knee score was 35,25 (range, 25 to 41) and the average pain Numerical Rating Scale (NRS) was 0,5 (range, 0 to 1). 3 Patients had postoperative anemia but no implant related complications has been reported. Complex DFF of the elderly treated with mega knee arthroplasty exhibit good clinical outcomes scores. The patients should be selected carefully as the complication rate found in the literature remains high.

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.

The effect of surgeon-controlled variables on construct stiffness in lateral locked plating of distal femoral fractures

Background

Nonunion following treatment of supracondylar femur fractures with lateral locked plates (LLP) has been reported to be as high as 21 %. Implant related and surgeon-controlled variables have been postulated to contribute to nonunion by modulating fracture-fixation construct stiffness. The purpose of this study is to evaluate the effect of surgeon-controlled factors on stiffness when treating supracondylar femur fractures with LLPs:

Does plate length affect construct stiffness given the same plate material, fracture working length and type of screws?

Does screw type (bicortical locking versus bicortical nonlocking or unicortical locking) and number of screws affect construct stiffness given the same material, fracture working length, and plate length?

Does fracture working length affect construct stiffness given the same plate material, length and type of screws?

Does plate material (titanium versus stainless steel) affect construct stiffness given the same fracture working length, plate length, type and number of screws?

Methods

Mechanical study of simulated supracondylar femur fractures treated with LLPs of varying lengths, screw types, fractureworking lenghts, and plate/screw material. Overall construct stiffness was evaluated using an Instron hydraulic testing apparatus.

Results

Stiffness was 15 % higher comparing 13-hole to the 5-hole plates (995 N/mm849N vs. /mm, p = 0.003). The use of bicortical nonlocking screws decreased overall construct stiffness by 18 % compared to bicortical locking screws (808 N/mm vs. 995 N/mm, p = 0.0001). The type of screw (unicortical locking vs. bicortical locking) and the number of screws in the diaphysis (3 vs. 10) did not appear to significantly influence construct stiffness (p = 0.76, p = 0.24). Similarly, fracture working length (5.4 cm vs. 9.4 cm, p = 0.24), and implant type (titanium vs. stainless steel, p = 0.12) did also not appear to effect stiffness.

Discussion

Using shorter plates and using bicortical nonlocking screws (vs. bicortical locking screws) reduced overall construct stiffness. Using more screws, using unicortical locking screws, increasing fracture working length and varying plate material (titanium vs. stainless steel) does not appear to significantly alter construct stiffness. Surgeons can adjust plate length and screw types to affect overall fracture-fixation construct stiffness; however, the optimal stiffness to promote healing remains unknown.

Endosteal substitution with medial plate in the treatment of acute distal femur fracture (AO/OTA type A): surgical technique and case-series

INTRODUCTION

Distal Femur fractures account for 4- 6% of all femur fractures and can be challenging to treat. The aims of this study are: (1) to describe a surgical technique using a medial distal femur endosteal plate to augment the stability of standard lateral plate fixation; (2) to report the results of a case-series of acute distal femur fractures (AO/OTA Type A/ Vancouver periprosthetic fractures Type C) treated using this technique.

METHODS

This study describes the surgical steps for placement of a medial endosteal plate in combination with lateral locking plate in a cadaver model using fluoroscopy guidance. In addition, a retrospective database chart review for all patients with acute distal femur fractures treated with this technique over the last five years was performed. Exclusion criteria were involvement of type B and C distal femur intraarticular fractures, treatment with other endosteal substitutions (i.e., intramedullary nail fixation and fibula allograft), and treatment for non-union or pathological fractures.

RESULTS

Twelve patients were identified with mean age of 75 years. All patients were female and all of them were allowed full weight bearing and full range of motion exercises immediately post-operatively. The complete follow up for one patient was not available; however, the mean fracture union was confirmed at 3.8 months in 10 of 12 patients. One patient had a failed construct at three months in the context of a periprosthetic fracture with a loose implant that was initially thought to be stable. One acute superficial surgical site infection was reported and healed uneventfully following debridement, primary closure, and antibiotic treatment.

CONCLUSION

We believe that the placement of a medial endosteal plate can be a useful augment for standard lateral plate fixation in acute distal femur fractures, particularly in the context of severe comminution or poor bone quality. Uneventful healing was confirmed in 10 of 12 cases and no patients were restricted with regard to motion or weight bearing immediately post-operatively. Further studies with larger sample size would be required to fully assess this technique.

LEVEL OF EVIDENCE

IV. Therapeutic Study (Surgical technique and Cases-series).

Interleukin-6 (IL-6) deficiency enhances intramembranous osteogenesis following stress fracture in mice

Interleukin-6 (IL-6) is highly upregulated in response to skeletal injury, suggesting it plays a role in the inflammatory phase of fracture repair. However, the impact of IL-6 on successful repair remains incompletely defined. Therefore, we investigated the role of IL-6 in two models of fracture repair (full fracture and stress fracture) using 12-week old IL-6 global knockout mice (IL-6 KO) and wild type (WT) littermate controls. Callus morphology and mineral density 14 days after full femur fracture did not differ between IL-6 knockout mice and controls. In contrast, IL-6 KO mice had an enhanced bone response 7 days after ulnar stress fracture compared to WT, with increased total callus volume (p = 0.020) and callus bone volume (p = 0.045). IL-6 KO did not alter the recruitment of immune cells (Gr-1 or F4/80 positive) to the stress fracture callus. IL-6 KO also did not alter the number of osteoclasts in the stress fracture callus. Using RNA-seq, we identified differentially expressed genes in stress fracture vs. contralateral control ulnae, and observed that IL-6 KO resulted in only modest alterations to the gene expression response to stress fracture (SFx). Wnt1 was more highly upregulated in IL-6 KO SFx callus at both day 1 (fold change 12.5 in KO vs. 5.7 in WT) and day 3 (fold change 4.7 in KO vs. 1.9 in WT). Finally, using tibial compression to induce bone formation without bone injury, we found that IL-6 KO directly impacted osteoblast function, increasing the propensity for woven bone formation. In summary, we report that IL-6 knockout enhanced formation of callus and bone following stress fracture injury, likely through direct action on the osteoblast's ability to produce woven bone. This suggests a novel role of IL-6 as a suppressor of intramembranous bone formation.