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

Infected Non-Union of the Distal Femur

The reported levels of non-union in the lateral locking plate differ widely, with some early studies showing rates of less than 6% and up to 17%-21% in more recent studies. We report a case where better results were shown by a non-union treated with distal femoral nailing with allogenic grafting.

Is Immediate Weight-Bearing Safe After Single Implant Fixation of Elderly Distal Femur Fractures?

OBJECTIVES

To compare early complications in elderly patients with extra-articular distal femur fractures (DFFs) allowed to weight-bear as tolerated (WBAT) immediately versus patients prescribed initial touchdown weight-bearing (TDWB).

DESIGN

Retrospective cohort study.

SETTING

Level 1 academic trauma center.

PATIENTS

One hundred thirty-five patients 60 years or older who underwent surgical fixation of an extra-articular DFF, including the OTA/AO fracture classification of 33-A1-3, and periprosthetic fractures with a stable knee prosthesis (Lewis and Rorabeck type I or II) with at least 6 months follow-up.

INTERVENTION

Immediate WBAT or TDWB after surgical fixation of an extra-articular DFF with either an intramedullary nail or locked plate.

MAIN OUTCOME MEASUREMENTS

The primary outcome was a major adverse event within the first 6 months, defined as (1) early fixation failure or change in alignment leading to reoperation, (2) nonunion, or (3) deep infection. Secondary outcomes included postoperative inpatient length of stay, discharge disposition (secondary facility vs. home), malunion, mortality, and patient-reported outcomes.

RESULTS

The rate of early adverse events requiring reoperation was similar between the WBAT group (6, 10.7%) and the TDWB group (15, 19.0%; P = 0.23). There was no difference between groups with respect to length of stay, discharge disposition, malunion, and patient-reported outcomes.

CONCLUSIONS

This study supports allowing carefully selected elderly patients, based on surgeon preference, to immediately weight-bear after operative fixation of an extra-articular DFF regardless of implant choice.

LEVEL OF EVIDENCE

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

[Distal femoral fractures in geriatric patients : Does time to surgery affect revision and mortality?]

BACKGROUND

For proximal femoral fractures the time to surgery has been reported to influence the mortality rate. To date, detailed analyses in geriatric patients with distal femoral fractures are not available.

MATERIAL AND METHODS

A monocentric study with retrospective data retrieved from an electronic database was performed. The study included distal femoral fractures with surgical treatment between 2006 and 2017 in patients aged 65 years and older. A total of ten variables were evaluated and two outcome measures were investigated: revision and mortality in relation to time of surgery within 24 h or later. The minimum follow-up was 2 years. For patients who were still alive the Parker score was calculated. The null hypothesis was that time to surgery does not affect revision and mortality.

RESULTS

A total of 57 consecutive patients with 60 fractures and an average age of 82.5 years (65-97 years) were included. Most of the fractures were supracondylar (n = 42). All but three fractures were treated with internal fixation. The revision rate was 17.5% (peri-implant fractures n = 4, infections n = 2, non-union n = 2, impaired wound healing n = 2 and secondary dislocation n = 1). The 1‑year mortality rate was 20%. No significant effects on revision (p = 0.414) and survival rate (log rank 0.175) were observed for patients treated within 24 h or later. After a mean postoperative period of 5.5 years, the mean Parker score for 18 living patients was 5.9.

CONCLUSION

Time to surgery demonstrated no significant effects with respect to revision and mortality. Multicenter studies are absolutely necessary to increase the sample size and statistical power.

Surgical outcomes of simple distal femur fractures in elderly patients treated with the minimally invasive plate osteosynthesis technique: can percutaneous cerclage wiring reduce the fracture healing time?

INTRODUCTION

Achieving adequate reduction is difficult when performing minimally invasive plate osteosynthesis (MIPO) in elderly patients with simple distal femur fracture. This study aimed to evaluate the elderly patients who had undergone percutaneous wiring-assisted reduction with MIPO for simple distal femur fractures to determine the effect of this technique on reduction quality and fracture union.

MATERIALS AND METHODS

Between January 2009 and September 2017, 56 patients (56 femurs) with displaced simple distal femur fractures treated with MIPO at three trauma centers were finally enrolled. The MIPO technique with percutaneous cerclage wire reduction was performed in 25 patients (Group A). Among them, 12 patients had a simple spiral metaphyseal fracture (Group A*). In comparison, MIPO without percutaneous cerclage wire reduction was performed in 31 patients (Group B). Among them, seven patients had a simple spiral metaphyseal fracture (Group B*). Medical records containing surgical records were retrospectively reviewed to investigate demographic data, comorbidities, complications, operative time, and fluoroscopic time. Radiographs were evaluated for assessing the quality of the reduction and fracture union.

RESULTS

The mean fracture union time of Group A* was 21.7 weeks, which was significantly shorter than that of Group B* (28.6 weeks). The mean coronal and sagittal angulation in Group A* was 0.6° and 0.7°, respectively, which were significantly lesser than those in Group B* (2.4° and 3.2°, respectively). Mean translation in Group A* was 1.43 mm, which was significantly shorter than that in Group B* (3.81 mm). Nonunion occurred in two patients in Group B.

CONCLUSION

Surgical treatment of simple spiral distal femur fractures with percutaneous cerclage wiring-assisted reduction and the MIPO technique in elderly patients resulted in better reduction and faster union time. Therefore, this technique could be a good solution if used in accordance with the indication.

Analysis of risk factors for revision in distal femoral fractures treated with lateral locking plate: a retrospective study in Chinese patients

BACKGROUND

To analyze the risk factors of revision operation after the treatment of distal femoral fracture with lateral locking plate (LLP).

METHODS

Retrospective analysis of the clinical data of 152 cases with distal femoral fracture treated in our hospital from March 2005 to March 2019. The SPSS 26.0 software (univariate analysis and logistic regression analysis) was used to analyze the general condition, fracture-related factors, operation-related factors, and construct characteristics of internal fixation.

RESULTS

Sixteen of 152 patients who were included in the study underwent revision surgery, with a revision rate 10.5%. Univariate analysis showed that there were significant differences in age, body mass index (BMI), fracture type, supracondylar involved or not, type of incision, quality of reduction, ratio of length of plate/fracture area (R1), the ratio of the length of the plate/fracture area above the condylar (R2), ratio of distance between proximal part of fracture and screw/working length of proximal plate (R3) between the two groups (P < 0.05). Logistic regression analysis showed that age [OR for age > 61.5 group is 4.900 (1.071-22.414)], fracture type [OR for A3 fracture is 8.572 (1.606-45.750), the OR for periprosthetic fracture after TKA is 9.073 (1.220-67.506)], poor reduction quality [OR is 7.663 (1.821-32.253)], and the ratio of the length of the plate/fracture area above the condylar were the possible risk factors (P < 0.05).

CONCLUSION

Age, fracture type (A3 and periprosthetic fracture after TKA), poor reduction quality, and the ratio of the length of the plate/fracture area above the condylar were the possible risk 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.

Early fixation failure of locked plating in complex distal femoral fractures: Root causes analysis

BACKGROUND/PURPOSE

Orthopaedic Trauma Association (OTA) C-type distal femoral fractures can be very challenging to treat effectively. While locked plating is widely used in the complex distal femoral fracture, failure of locked plate fixation is not uncommon. First, we tried to determine the risk factor related to early failure of multiplanar OTA C-type fracture in the distal femur after fixation with lateral locked plate. Second, we tried to provide a strategy for surgeons to prevent pitfalls of early failure in the complex distal femoral fractures treated with lateral locked plating.

METHODS

We retrospectively reviewed 44 adults with OTA C-type fractures of the distal femur treated with locked plate fixation between 2010 and 2016 at Tri-Service General Hospital. Average length of follow-up was 27.6 months (range, 12-54 months). Univariate and multivariate logistic regression were used to determine the association of variables on early failure of fixation. A p-value < 0.05 in univariate and multivariate analyses were considered significant.

RESULTS

There were six patients experiencing early failure, and the early failure rate was 13.6%. The risk factors associated with early failure of complex distal femoral fracture identified by univariate analysis included sagittal oblique fracture pattern, longer working length and post-operative sagittal malalignment (odds ratio [OR] and 95% confidence intervals [CI]: 90.00 (6.85-1183.33), 0.55 (0.31-0.98) and 8.63 (1.077-69.075) respectively). The multivariate analysis showed only sagittal oblique fracture pattern was associated with early failure [OR: 52.348 (3.06-895.23)].

CONCLUSION

Sagittal oblique fracture was more likely to result in early postoperative failure. Early recognition of the fracture pattern should be considered to avoid catastrophic results.

Epidemiology, Clinical Assessments, and Current Treatments of Nonunions

PURPOSE OF REVIEW

The failure of bony union following a fracture, termed a fracture nonunion, has severe patient morbidity and economic consequences. This review describes current consensuses and future directions of investigation for determining why, detecting when, and effective treatment if this complication occurs.

RECENT FINDINGS

Current nonunion investigation is emphasizing an expanded understanding of the biology of healing. This has led to assessments of the immune environment, multiple cytokines and morphogenetic factors, and the role of skeletogenic stem cells in the development of nonunion. Detecting biological markers and other objective diagnostic criteria is also a current objective of nonunion research. Treatment approaches in the near future will likely be dominated by the development of specific adjunct therapies to the nonunion surgical management, which will be informed by an expanded mechanistic understanding of nonunion biology. Current consensus among orthopedists is that improved diagnosis and treatment of nonunion hinges first on discoveries at the bench side with later translation to the clinic.

The effects of dual plating on the vascularity of the distal femur

AIMS

Dual plating of distal femoral fractures with medial and lateral implants has been performed to improve construct mechanics and alignment, in cases where isolated lateral plating would be insufficient. This may potentially compromise vascularity, paradoxically impairing healing. This study investigates effects of single versus dual plating on distal femoral vascularity.

METHODS

A total of eight cadaveric lower limb pairs were arbitrarily assigned to either 1) isolated lateral plating, or 2) lateral and medial plating of the distal femur, with four specimens per group. Contralateral limbs served as matched controls. Pre- and post-contrast MRI was performed to quantify signal intensity enhancement in the distal femur. Further evaluation of intraosseous vascularity was done with barium sulphate infusion with CT scan imaging. Specimens were then injected with latex medium and dissection was completed to assess extraosseous vasculature.

RESULTS

Quantitative MRI revealed a mean reduction of 21.2% (SD 1.3%) of arterial contribution in the lateral plating group and 25.4% (SD 3.2%) in the dual plating group (p = 0.051); representing a mean decrease in arterial contribution of 4.2%. The only significant difference found between both experimental groups was regionally, at the lateral aspect of the distal femur with a mean drop in arterial contribution in the lateral plating group of 18.9% (SD 2.6%) versus 24.0% (SD 3.2%) in the dual plating group (p = 0.048), representing a mean decrease in arterial contribution of 5.1%. Gross dissection revealed complete destruction of periosteal vessels underneath either medial or lateral plates in both groups. The network of genicular branches contributing to the posterior and distal femoral condyles was preserved in all specimens. A medial vascular pedicle was found dividing from the superficial femoral artery at a mean 12.7 cm (SD 1.7) proximal to the medial epicondyle and was undisrupted in the dual plating group.

CONCLUSION

Lateral locking-plate application resulted in mean 21.2% reduction in distal femur vascularity. Addition of medial plates did not further markedly decrease vascularity. As such, the majority of the vascular insult occurred with lateral plating alone. Supplemental medially based fixation did not lead to marked devascularization of the distal femur, and should therefore be considered in the setting of comminution and poor bone stock in distal femoral fractures. Further clinical research is required to confirm the results of this study. Cite this article: Bone Joint J 2020;102-B(4):530-538.

Corrective Intra-Articular Osteotomy Using a 3D-Printed Model and Induced Membrane Technique for AO/OTA C3 Distal Femur Fracture with Articular Malunion and Metaphyseal Nonunion

Comminuted distal femur fracture is a challenging injury, and care must be taken to reduce the articular fragment and acquire the sufficient stability for the metaphyseal comminution. We report the case of a AO/OTA C3-type distal femur fracture with articular malunion and metaphyseal nonunion. Articular malunion was treated with corrective osteotomy using a 3D-printed model for planning, and metaphyseal nonunion was treated with an induced membrane technique. Conclusion. Two major complications in the comminuted periarticular fracture can be addressed by an osteotomy and induced membrane technique. A 3D-printed model is a useful tool to evaluate the morphology of the malunited articular surface.

Radiostereometric Analysis of Stability and Inducible Micromotion After Locked Lateral Plating of Distal Femur Fractures

OBJECTIVES

To evaluate interfragmentary motion over 1 year after distal femoral fracture fixation using radiostereometric analysis (RSA). The secondary aim was to assess whether RSA data are consistent with diagnoses of nonunion.

DESIGN

Prospective cohort study.

SETTING

Level I urban trauma center.

PATIENTS

Sixteen patients between 22 and 89 years of age with distal femoral fracture (OTA/AO type 33).

INTERVENTION

All fractures were treated with a lateral locking plate, and tantalum markers were inserted into the main proximal and distal fracture fragments. RSA was performed at 2, 6, 12, 18, and 52 weeks postoperatively. Both unloaded and loaded RSA measurements were performed.

MAIN OUTCOME MEASUREMENTS

Unloaded fracture migration over time and inducible micromotion at the fracture site in the coronal plane were determined at each follow-up interval.

RESULTS

RSA precision in the coronal plane of interfragmentary motion over time and inducible micromotion were 1.2 and 0.9 mm in the coronal plane, respectively. Two cases required revision surgery for nonunion 1 year postoperatively. For cases of union, unloaded fracture migration stopped being detectable between 12 and 18 weeks, and inducible micromotion was no longer detectable by the 12-week visit. For cases of nonunion, both unloaded migration and inducible micromotion were detected throughout the study period.

CONCLUSIONS

RSA may be used to reliably assess distal femoral fracture healing. RSA revealed differences in cases of union and nonunion by 3 months and more consistently than traditional x-rays.

LEVEL OF EVIDENCE

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

Failure of Less-Invasive Stabilization System (LISS) plating for periprosthetic distal femur fractures: Three case reports

RATIONALE

Less-Invasive Stabilization System (LISS) plate is an internal fixation commonly used for the periprosthetic distal femur fractures. Failure associated with LISS plate has been rarely reported, and the reasons for LISS plate failure are multitudinous. Various advantages have been reported, but failures continue.

PATIENT CONCERNS

We present 3 cases illustrating the failure of Less-Invasive Stabilization System (LISS) plating for periprosthetic distal femur fractures. The shaft screws of the LISS plate broke in 2 cases, and the plate placement was incorrect in 1 case. Early weight bearing, obesity, osteoporosis, and lateral collateral ligament injury due to incorrect plate placement constituted the etiologies of LISS plate failure.

DIAGNOSIS

Failure of Less-Invasive Stabilization System (LISS) plating for periprosthetic distal femur fractures after Total knee arthroplasty.

INTERVENTIONS

Three patients underwent Less-Invasive Stabilization System plates removal with replacement of the total knee arthroplasty revision surgery with rotating hinged knee prosthesis.

OUTCOMES

After completing the total knee arthroplasty revision surgery, all patients underwent regular follow-up examinations. Case 2 could walk unaided, without pain, final union was confirmed for both case 1 and case 3.

CONCLUSION

Less-Invasive Stabilization System (LISS) plate provides satisfactory results in periprosthetic fractures after Total knee arthroplasty (TKA). The LISS plate has many advantages, but failures continue to occur. The causes for failure were early weight bearing, obesity, osteoporosis, and lateral collateral ligament (LCL) injury due to incorrect plate placement in our series. We recommend that protection or properly delay of weight-bearing, active anti-osteoporosis treatment, and intraoperative fluoroscopy are the effective methods to avoid failure.

Osteoporotic distal femur fractures in the elderly: peculiarities and treatment strategies

Distal femur fractures account for 4-6% of osteoporosis related fractures of the femur in the elderly population. They represent a relevant cause of morbidity and mortality in the geriatric population with a reported 1-year mortality reaching 30%. Non-displaced fractures or even displaced fractures in patients with high operative risk can be treated conservatively. However, operative treatment is the most widely accepted management option for displaced fractures. The advantage resides in early mobilization and weight-bearing, reducing risks related with a prolonged immobilization when compared with conservative treatment. On the other hand, the intrinsic difficulty of fixing an osteoporotic bone is a major concern. The presence of osteosynthesis devices or prosthetic implants in the femur can make the surgical treatment more challenging, sometimes limiting therapeutic options. Aim of the present paper is to review the most recent literature about osteoporotic distal femur fractures in the elderly, including periprosthetic and other hardware related fractures, to highlight current evidence on management options and related results as a guide for the daily clinical practice.

Non-union in lateral locked plating for distal femoral fractures: A systematic review

INTRODUCTION

This study aims to identify patient and intra-operative factors that contribute to non-union in locked lateral plating for distal femoral fractures.

METHODS

Systematic searches of English-language articles in Ovid Medline, PubMed, Embase, Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews were undertaken in February 2018 according to the PRISMA guidelines. The search terms were (fracture or fracture*) AND (distal femur or distal femoral) AND (malunion or non-union). Eligible studies published at any time reported non-union rates and compared patient and intraoperative factors in patients who underwent locked lateral plating for traumatic distal femoral fractures. The quality of included papers was assessed using The Journal of Bone and Joint Surgery levels of evidence (Wright et al., 2003), and further appraised using the Downs and Black score (Downs and Black, 1998).

RESULTS

Eight studies investigating 1380 distal femoral fractures were found to satisfy the inclusion and exclusion criteria. These studies analysed a variety of patient and intra-operative factors that may contribute to non-union. These include high BMI, open fracture, comminution, fracture infection, stainless steel plate material, shorter working length, open reduction and internal fixation when compared with minimally invasive plate osteosynthesis, high construct rigidity scores and purely locking screw constructs.

CONCLUSION

This review has identified multiple factors which potentially contribute to non-union including stainless steel plate material, high construct rigidity scores and purely locking screw constructs. These findings may reflect that overly rigid plating constructs can contribute to non-union. However, they should be taken in the context of heterogeneity amongst included studies, with further research necessary to support these findings.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Early clinical and radiographic outcomes of a mini-fragment, low profile plating system in tibial plafond fractures

OBJECTIVE

The Smith and Nephew mini-EVOS plating system is a mini-fragment, low profile, variable-angled plating system designed to obtain anatomic reduction while also minimizing soft tissue handling. However, literature has been limited in reporting the clinical and surgical outcomes of these specific plates. The goal of our study is to evaluate the safety and efficacy of the Smith and Nephew mini-EVOS plate in pilon fracture management, where significant high energy forces can result in severe fracture patterns and soft tissue injury.

METHODS

Patients 18-65 years of age who underwent plate fixation of their tibial plafond fractures (OTA/AO) using the Smith and Nephew mini-EVOS plating system at our urban university-based level-1 trauma center were included in this retrospective investigation. A total of 37 patients (37 fractures) from January 2015 to March 2018 were included in this study. Primary outcome measure was mechanical hardware failure. Secondary outcome measures included nonunion, malunion, medical and surgical complications.

RESULTS

The fractures were classified according to the OTA/AO classification as 43C1 (n = 15), 42C2 (n = 6), and 43C3 (n = 16). A mechanical failure was observed in three patients (8.1%). Six additional patients needed a re-operation of the surgical site including two nonunion repairs, one malunion repair, one symptomatic hardware removal, and two soft tissue debridements. The mean follow-up was 298.9 days (range: 96-936).

CONCLUSIONS

Early results of operative fixation of tibial plafond fractures using the Smith-Nephew mini-EVOS demonstrated low hardware failure and complication rates. This plating system is a safe and effective implant.

LEVEL OF EVIDENCE

Therapeutic Level IV.

Additional fixation of medial plate over the unstable lateral locked plating of distal femur fractures: A biomechanical study

INTRODUCTION

Lateral locked plating is a standard treatment option for distal femur fractures. However, the unstable conditions after lateral locked plating are increasing. The objective of this study was to investigate the biomechanical strength of additional medial plate fixation over the unstable lateral locked plating of distal femur fractures.

MATERIALS AND METHODS

A distal femur fracture model (AO/OTA 33-A3) was created with osteotomies in the composite femur. Three study groups consisting of 6 specimens each were created for single-side lateral locked plating with 6 distal locking screws (LP-6), single-side lateral locked plating with 4 distal locking screws (LP-4), and additional medial locked plating on LP-4 construct (DP-4). A compressive axial load (10 mm/min) was applied in the failure test. Mode of failure, load to failure, and ultimate displacement were documented.

RESULTS

All single-side lateral locked plating (LP-4 and LP-6) showed plate bending at the fracture gap, while none of the DP-4 showed plate bending at the fracture gap. Load to failure of DP-4 (mean 5522 N) was 17.1% greater than that of LP-6 (mean 4713.3 N, p < 0.05) and 29.2% greater than that of LP-4 (mean 4273.2 N, p < 0.05). Ultimate displacement of DP-4 (mean 5.6 mm) was significantly lower than that of LP-6 (mean 8.8 mm, p < 0.05) and LP-4 (mean 9.1 mm, p < 0.05).

CONCLUSIONS

Additional fixation of medial plate significantly increased the fracture stability in distal femur fractures fixed with the lateral locked plating. Especially in the clinical situations where sufficient stability cannot be provided at the distal segment, the medial plate may be considered as a useful biomechanical solution to obtain adequate stability for fracture healing.

Dual plate fixation results in improved union rates in comminuted distal femur fractures compared to single plate fixation

Purpose

The treatment of distal femur fractures with extensive metaphyseal comminution is frequently complicated by high rates of nonunion and varus collapse. Dual plating with lateral and medial locking plates for these types of fractures has shown promising results in the recent literature. We hypothesize that dual plating of comminuted distal femur fractures leads to higher union rates and lower revision rates compared to an isolated lateral locking plate.

Methods

A retrospective medical chart review between January 2015 and December 2017 was conducted. Inclusion criteria included patients 18 years of age and older who sustained a complex distal femur fracture (AO/OTA 33-C2/33-C3 or periprosthetic fracture with significant metaphyseal comminution) and at least 6 months of follow up. Patients with simple fracture patterns, alternative fixation methods, and inadequate follow up were excluded. All patients in the single plating group were treated with a lateral distal femoral locking plate using a lateral approach. In the patients treated with dual plating, an extensile parapatellar approach was utilized for fracture reduction and placement of an adjunctive medial plate. Demographic information, fracture types, injury severity score (ISS), medical comorbidities, type of surgical fixation, union rates, complications, knee range of motion, time to follow up, and need for revision surgery were extrapolated from the medical charts for analysis.

Results

Twenty-one patients were included in the study. Thirteen patients underwent single plate fixation and 8 underwent dual plate fixation. There were no significant differences in demographics, number of co-morbidities, fracture classification, or ISS between single and dual plate groups (p > 0.05 for all). There was a statistically significant difference in union rates between the single plate group (6 nonunions, 4 unions, and 3 delayed unions) and the dual plate group, with no nonunions or delayed unions (p = 0.0049). Although not statistically significant, 4 patients treated with single plating underwent revision ORIF, compared to none in the dual plating group (p = 0.13). There were no significant differences in time to follow up, time to full weight bearing, or infection rates (p > 0.1 for all).

Conclusion

Based on these results, the medial and lateral locked plating technique demonstrates a higher union rate, with possible lower rates of revision surgery, compared to a single lateral plate in highly comminuted distal femur fractures.

Level of evidence

Level 3. Retrospective Cohort Study.

Prevalence of Deep Surgical Site Infection After Repair of Periarticular Knee Fractures: A Systematic Review and Meta-analysis

IMPORTANCE

Surgical management of periarticular knee fractures can be challenging, and adverse outcomes may be severe. Recent literature indicates that the rate of periarticular knee surgical site infection (SSI) may range from 2% to 88% depending on the fracture site.

OBJECTIVE

To examine the prevalence of deep SSI and the rate of septic arthritis after surgical repair of fractures around the knee.

DATA SOURCES

The electronic databases MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched from their inception to July 1, 2018.

STUDY SELECTION

Eligible studies had to specifically report deep SSI rates and include fractures in the distal femur, patella, tibial plateau, or proximal tibia. Risk factors that were associated with increased the risk of deep SSI were also examined.

DATA EXTRACTION AND SYNTHESIS

This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. Data were extracted by multiple investigators. Comprehensive Meta-Analysis software was used for the pooling of data, using either random-effects or fixed-effects models, with respect to the degree of statistical heterogeneity present. Data analyses were conducted in October 2019.

MAIN OUTCOMES AND MEASURES

The primary outcome was overall prevalence of deep SSI after periarticular knee fracture repair. The secondary outcomes were the overall prevalence of septic arthritis, risk factors associated with deep SSI, and the most commonly cultured bacteria specimens found periarticular knee infections.

RESULTS

Of 6928 articles screened, 117 articles met inclusion criteria and were included in analysis. Among 11 432 patients included in analysis, 653 patients (5.7%) experienced deep SSIs, most commonly among patients with proximal tibia fractures (56 of 872 patients [6.4%]). Among studies that included information on septic arthritis, 38 of 1567 patients (2.4%) experienced septic arthritis. The 2 most commonly reported bacteria were methicillin-resistant Staphylococcus aureus, found in 67 SSIs, and methicillin-susceptible S aureus, found in 53 SSIs. Sixty-two studies (53.0%) in the sample received a Coleman Methodological Score of poor (<50 points).

CONCLUSIONS AND RELEVANCE

Deep SSIs occurred in nearly 6% of periarticular knee fracture repairs, and 2.4% of SSIs were associated with septic arthritis. Surgeons managing these injuries should be vigilant when wounds are not pristine. Efforts should be made to elevate the quality of research conducted not only in this subject but also in orthopedic surgery as a whole.

Nonunited Lower Extremity Fractures Initially Repaired Outside the Developed Western World Develop a High Rate of Postoperative Complications After Nonunion Repair

OBJECTIVES

To evaluate the clinical and functional outcomes after operative repair of nonunited lower extremity fractures initially repaired outside the developed Western world.

DESIGN

Retrospective analysis of prospectively collected data.

SETTING

Academic medical center.

PATIENTS/PARTICIPANTS

From September 2004 through February 2017, 227 patients who underwent operative repair of a lower extremity fracture nonunion were prospectively enrolled in a research registry. All patients underwent previous fracture surgery and had at least 12 months of postoperative follow-up.

INTERVENTION

Repair of lower extremity fracture nonunion.

MAIN OUTCOME MEASUREMENTS

Postoperative complications, reoperation rate, time to union, and functional outcomes were assessed using the Short Musculoskeletal Function Assessment and Visual Analog Scale pain scores. Univariate and multivariate analyses were performed to evaluate the differences in patients who underwent initial fracture repair outside the developed Western world as opposed to within the United States.

RESULTS

Twenty-one patients (9.3%) underwent initial fracture repair outside the developed Western world. These patients had a greater incidence of infected nonunions (47.6% vs. 23.3%; P = 0.015) and failure of a previous implant at the time of presentation (52.4% vs. 22.8%; P = 0.003) than those initially managed within the United States. This cohort also experienced a greater rate of postoperative complications after nonunion repair (23.8% vs. 6.3%; P = 0.016). The geographic location of initial fracture repair was not associated with postoperative Short Musculoskeletal Function Assessment scores or Visual Analog Scale pain scores after controlling for possible confounding variables.

CONCLUSIONS

Patients who present with a nonunited lower extremity fracture initially repaired outside the developed Western world experience a high rate of postoperative complications after fracture nonunion repair but can expect good short- and long-term functional outcomes.

LEVEL OF EVIDENCE

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

Early versus delayed weight bearing after surgical fixation of distal femur fractures: a non-randomized comparative study

Distal femur fractures are rare injuries with a bimodal distribution (high-energy injury in young males and low-energy fragility fractures in old females). Their management can be challenging: open reduction and internal fixation (ORIF) with distal femur locking plates is a commonly performed procedure especially in comminuted fractures with articular involvement. Anxiety regarding the stability of the fixation, especially in osteoporotic bone, leads to post-operative restrictive instructions with limitations regarding the weight-bearing status. Early weight bearing (EWB), however, was shown to enhance bone healing and was not correlated with an increased risk of fracture displacement or implant failure in previous published studies, which reported the results of proximal femur, tibia and ankle fractures surgical treatment. The current study analysed the results of a series of distal femur fractures (51 patients, mean age 64.3 ± 20.7) all treated with ORIF in a level-I major trauma centre, but differently rehabilitated. Group A was, in fact, instructed not to weight bear or to touch weight bear, while group B started to weight bear soon after surgery without specific restrictions. The objective was to compare the outcome and the complication rate in the two groups at 6 and 12 weeks after surgery. The results showed no statistically significant differences in the two groups and no post-operative complications in the EWB group. Six complications were observed in the non-weight-bearing group (four fractures displacement and two implants failure at 12-week follow-up). Distal femur fractures treated with locking plates can be rehabilitated with EWB to allow early return to function. There is no evidence that EWB increases the risk of fracture displacement or implant failure in distal femur fractures treated with distal locking plates. Instead, it is possible that post-operative non-weight-bearing status delays the fracture-healing process increasing the risk of failure of the fixation.

Comparison of outcomes and analysis of risk factors for non-union in locked plating of closed periprosthetic and non-periprosthetic distal femoral fractures in a retrospective cohort study

BACKGROUND

The primary aim was to compare the outcomes of locked plating of closed distal femur periprosthetic and non-periprosthetic fractures by testing the hypothesis that outcomes would be worse in the periprosthetic group. The secondary aim of this study was to identify risk factors for non-union.

METHODS

A single-center study over an 8-year period utilizing a retrospective cohort design was performed. Sixty-eight patients with periprosthetic fractures and 57 patients with non-periprosthetic fractures met inclusion criteria for the study. There was a significant difference between groups in mean age (80.1 years periprosthetic vs. 70.9 years non-periprosthetic (p < 0.001)). Statistical analysis between groups was used to assess the outcomes of time to union, incidence of non-union, post-operative functionality, incidence of complications, progression to revision surgery, and mortality. A secondary multivariable analysis was used to assess risk factors for non-union and factors positively associated with union.

RESULTS

There were no significant differences in outcomes between groups. Union rates were 83.8% (57/68) in the periprosthetic group and 78.9% (45/57) in the non-periprosthetic group (p = 0.648). Comminution was identified as a significant risk factor for non-union (p = 0.005). Use of a submuscular technique had a significant positive association with union (p = 0.006).

CONCLUSIONS

Outcomes of surgical treatment for periprosthetic and non-periprosthetic distal femur fractures are similar. There is a significant risk of non-union in locked plating of both groups.

Functional outcome of open distal femoral fractures managed with lateral locking plates

PURPOSE

This prospective study evaluated the functional outcome and union rates of open distal femoral fractures managed with anatomic lateral locking plates.

METHODS

Thirty-four patients with open distal femur fractures with mean age of 40.8 years (range 20-65 years) were included in the study. Patients with Gustilo-Anderson grade IIIC fractures and those managed with non-locking modalities were excluded. In total, 70.6% (n = 24) of the fractures were Type IIIA and 55.9% (n = 19) were AO/OTA Type C3 fractures. In 23.5% (n = 8) patients, knee spanning external fixator was applied initially before definitive fixation. Patients were followed up for a mean period of 11.6 months (range 8-22.5 months). Functional outcome was evaluated using Sanders Score.

RESULTS

In the primary plating group, 69.2% (n = 18) fractures united at an average of 27 weeks (range 21-40 weeks), while eight patients had non-union and required bone grafting. All eight patients with external fixator underwent lateral locked plating with bone grafting and united at an average time of 39.6 weeks (range 31-50 weeks). There were two cases each of infection and screw failure. The final mean Sanders Score was 30.1 (range19-40) with 73.5% (n = 25) patients having good to excellent functional outcomes.

CONCLUSIONS

Lateral locking plates offer excellent stability to allow fracture union in open distal femoral fractures. A proactive approach to identify and manage potential healing difficulties is advisable to promote bone healing.

Clinical effects and risk factors of far cortical locking system in the treatment of lower limb fractures

INTRODUCTION

This study aims to analyze clinical effects between far cortical locking (FCL) system and standard plating techniques in the treatment of lower limb fractures and identify potential preoperative risk factors for complications in patients treated with FCL system.

METHOD

We retrospectively analyzed 76 patients treated with FCL system (the study group) and 68 patients treated with standard plating techniques (the control group) between January 2014 and January 2017. Patients were followed up for a minimum of one year. Surgery-related complications, fixation features, fracture healing rates, the radiographic union scores, and knee functions (Kolment scores) were analyzed between the two groups in the study. Besides, we analyzed eight preoperative characteristics for surgery-related complications, including age, gender, presence of risk factors affecting bone healing, cause of injury, AO/OTA fracture classifications, facture sites, presence of open fractures, and presence of bone losses.

RESULTS

The distributions of baseline date were similar between the two groups (P＞0.05). The average number of FCL screws was 4.5 (range: 3-9) in the study group. The average time to union was 2.8 ± 0.9 months in the study group and 3.6 ± 1.0 months in the control group (P＜0.001), and average time to whole weight bearing was 2.3 ± 0.8 months and 2.8 ± 1.2 months, respectively (P = 0.004). Regarding radiographic union score, the study group scores were significantly higher than the control group scores at 1 and 3 months after surgery (P＜0.001), while it becomes insignificant between the two groups at 6 and 12 months after surgery (P = 0.19 and P = 0.15).The working lengths, fracture healing rates, complication rates, and Kolment scores were similar between the two groups (P＞0.05). In the multivariate analysis, fracture sites (OR = 5.34; 95% CI, 1.11-25.75; P = 0.03) and presence of open fractures (OR = 6.19; 95% CI, 1.05-36.38; P = 0.04) were significant associated with complications, whereas other variables were not included.

DISCUSSION

FCL system can truly accelerating bone healing and allow earlier whole weight bearing. Fracture healing rates and complication rates were similar between patients treated with FCL implants or conventional plating techniques. Patients with shaft fractures and open fractures trended to have higher complication rates.

CONCLUSIONS

FCL system is superior to standard plating technique in terms of early callus formation, but standard plating technique is not inferior to FCL system in terms of final fracture healing, surgery-related complication, and function outcome. Fracture site and presence of open fracture are the independent factors for complications in patients treated with FCL system.

Geriatric distal femoral fractures: A retrospective study of 30 day mortality

INTRODUCTION

Distal femoral fractures have many of the same challenges as hip fractures, but there has been limited research into outcomes following these. The aim of this study was to assess 30 day mortality following distal femoral fractures in comparison to hip fractures presenting to a single institution Secondary outcomes included risk factors for mortality, post-operative complications and union.

METHODS

A retrospective case series of all distal femoral fragility fractures in patients over 65, and hip fractures over a 5 year period at a single institution.

RESULTS

88 distal femoral fractures and 2837 hip fractures fulfilled the inclusion criteria. In the distal femoral fractures there were 80 females and 8 males with a mean age of 82.4 (range 65-103). The mean age of the hip fractures was 83.7 (range 65-106) and there were 2066 females and 771 males. The overall 30 day mortality for hip fractures was 7.7% and was 9.1% for distal femoral fractures. The risk ratio was 1.1777(95% CI 0.6009-2.3080) (p = 0.6338). There was no significant difference in 30 day mortality between the two fracture types. Of the 88 distal femoral fractures 75 (85.2%) underwent open reduction internal fixation, 5 (5.7%) intramedullary nail and 8 (9.1%) conservative treatment. 11.4% suffered a medical complication. 9.1% patients required at least 1 further surgical procedure. The union rate was 94.3%. The 1 year mortality was 34.1%.

CONCLUSIONS

There is no significant difference in 30 day mortality between distal femoral and hip fractures. Distal femoral fractures occur in a complex group of patients that is similar to hip fractures. They have high mortality and complication rates.

Far Cortical Locking Fixation of Distal Femur Fractures is Dominated by Shear at Clinically Relevant Bridge Spans

OBJECTIVES

Far cortical locking (FCL) constructs have been shown to increase axial interfragmentary displacement while limiting shear and have been specifically recommended in the treatment of distal femur fractures. However, there is no available data regarding their mechanical behavior within the range of bridge spans typically used for comminuted distal femur fractures. This biomechanical study of distal femur locked plate fixation assessed 4 methods of diaphyseal fixation for associated axial and shear displacement at bridge spans typically used in clinical practice.

METHODS

Distal femur locking plates were used to bridge simulated fractures in femur surrogates with 4 different methods of diaphyseal fixation (bicortical locking, bicortical nonlocking, near cortical locking, and FCL). Axial and shear displacement were assessed at 5 different bridge spans for each fixation method.

RESULTS

Diaphyseal fixation type was associated with the amount of shear (P = 0.04), but not the amount of axial displacement (P = 0.39). Specifically, FCL constructs demonstrated greater shear than bicortical locking (median 4.57 vs. 2.94 mm, P = 0.02) and bicortical nonlocking (median 4.57 vs. 3.41 mm, P = 0.02) constructs.

CONCLUSIONS

Unexpectedly, FCL constructs demonstrated greater shear than bicortical locking and nonlocking constructs and similar axial displacement for all fixation methods. Bridge span had a dominant effect on displacement that interacted negatively with more flexible FCL diaphyseal fixation. Potentially interactive construct features are best studied in concert. Given the complexity of these relationships, computational modeling will likely play an integral role in future mechanotransduction research.

Low risk of nonunion with lateral locked plating of distal femoral fractures-A retrospective study of 191 consecutive patients

INTRODUCTION

The reported rate of nonunion of distal femoral fractures varies in the literature. Several risk factors for nonunion following lateral locked plating (LLP) have been described. We aimed to study the rate of nonunion, and risk factors thereof, in a Swedish population where fragility fractures are common. A secondary aim was to study risk factors for reoperation for any cause.

PATIENTS AND METHODS

We retrospectively reviewed the hospital files and radiographs of all adult patients admitted to our institution with a distal femoral fracture, from 2004 through 2013. In cases treated with LLP, medical comorbidities, fracture characteristics and implant characteristics were analysed as potential risk factors for nonunion, defined as any surgical intervention to improve healing.

RESULTS

There were 8 cases (4%, 95%CI: 1.8-8.1%) of nonunion in 191 fractures treated with LLP. Patients with nonunion were younger: 62 vs. 81 years (p = 0.009) and more commonly had open fractures: 38% vs. 9% (p = 0.034). No patient 80 years or older had a surgical intervention for nonunion. Lower age was independently associated with reoperation for any cause, but not for nonunion.

DISCUSSION

The low rate of nonunion in this study is probably due to the fact that we present data from a complete cohort from a geographic catchment area. Referral centres with a high proportion of young patients with high-energy injuries, may be better suited for studies on risk factors for nonunion, due to higher statistical power. However, results from such institutions may not be generalizable to the more common low-energy fractures.

Evaluating the susceptibility of AGO2-loaded microRNAs to degradation by nucleases in vitro

MicroRNAs (miRNAs) comprise a class of small non-coding RNAs that regulate the stability and/or translatability of most protein-coding transcripts. Steady-state levels of mature miRNAs can be controlled through mechanisms that influence their biogenesis and/or decay rates. Pathways that mediate mature miRNA decay are less well understood than those that mediate miRNA biogenesis. We recently described Tudor-staphylococcal/micrococcal-like nuclease (TSN)-mediated miRNA decay (TumiD) as a cellular pathway that promotes the sequence-specific endonucleolytic decay of miRNAs that harbor a CA and/or UA dinucleotide. Here, we describe an in vitro assay for evaluating the susceptibility of AGO2-loaded miRNAs to degradation by different classes of nucleases. This in vitro approach can be used to complement in vivo studies that aim to identify novel miRNA decay factors.

Periprosthetic femoral nonunions treated with internal fixation and bone grafting

INTRODUCTION

Periprosthetic femoral nonunions (PPFN) have a reported incidence of 3-9%. Literature on PPFN management is scarce. The study aim was to review combined results of two academic teaching hospitals using comparable PPFN treatment strategies.

MATERIALS AND METHODS

A retrospective review was conducted of all patients treated for a PPFN between February 2005 and December 2016. All patients treated with internal fixation for a PPFN with complete clinical and radiological follow-up until healing were included. Nineteen patients were identified (mean age 71.2 years, range 49-87). Treatment consisted of failed hardware removal, debridement, reduction, and rigid internal fixation with or without bone graft. For revision PPFN surgery, use of dual-plating and bone graft augmentation was common.

RESULTS

Eighteen of 19 patients (94.7%) progressed to osseous union. One patient was converted to a total femoral prosthesis. No patients were lost to follow-up. All were ambulatory at last follow-up and mean follow-up was 39.8 months. Fourteen patients (73.7%) united after our index nonunion surgery at mean 9.8 months. Five patients (26.3%) required revision surgery after our index nonunion treatment and in 4 of these cases union was achieved at mean 18.0 months.

CONCLUSIONS

Our results suggest debridement, revision of fixation and liberal use of bone grafting can lead to reliable healing in the majority of PPFNs. For those PPFNs that do not heal following initial treatment, good healing potential persists with an additional procedure.

LEVEL OF EVIDENCE

Prognostic Level III.

Single-Incision Double-Plating Approach in the Management of Isolated, Closed Osteoporotic Distal Femoral Fractures

INTRODUCTION

Distal femoral fractures in elderly population had recorded an increase in incidence in the last 2 decades. Lateral distal femoral locking plating is considered one of the best options especially when dealing with comminuted fractures but varus collapse of the medial femoral condyle occurs frequently in patients with osteoporosis. Anatomical reduction of the fracture with stable rigid fixation using double-plating approach allows early mobilization of geriatric population and prevents varus collapse minimizing the comorbidities in such fractures.

PATIENTS AND METHODS

Between September 2014 and January 2017, a prospective study on 23 patients with comminuted osteoporotic distal femoral fractures managed through the double-plating approach through a single parapatellar approach has been conducted. Only osteoporotic geriatric patients with isolated distal femoral fractures were included. Polytraumatized, open fractures, and fracture type 33-A1, 33-A2, and 33-B were excluded. The mean age was 69.6 years (61-80). All patients have been evaluated as regard duration of procedure, time to union, EQ-5D-5L score, the need of autologous bone grafts, range of knee motion, and presence of complications.

RESULTS

The average follow-up was 14.1 months. The majority of fractures were type 33-C2 (13 patients). Average procedure time was 148 minutes (117-193 minutes). Mean EQ-5D-5 L score was 83.8 (72-82). Average time to union was 9 months (3-12 months). Four (17.4%) cases needed autologous bone graft after 6 months. No loss of reduction in any of the cases was evident, although 6 (26%) cases had screw breakage or cutout in one of the plate fixation. Two (8.7%) patient developed superficial wound infection and 1 (4.3%) developed DVT.

DISCUSSION

This study aimed at evaluation of the success of double plating of distal femoral fractures in geriatric population. different fixation methods were studied for reduction and fixation of such a fracture such as external fixation, intramedullary nails and lateral plating. the quality of fracture reduction, functional and radiological outcomes, time to union, the need for bone grafting and complication are the main debatable issues.

CONCLUSION

Single-incision double-plating approach for distal femoral osteoporotic fractures is effective and provides stable construct without reduction loss allowing early rehabilitation. Delayed union and the need for bone graft are the major drawbacks for this technique.

Outcomes of distal femur fractures treated with the Synthes 4.5 mm VA-LCP Curved Condylar Plate

PURPOSE

Given the recent controversy in the literature and the alarming reports of early mechanical failure associated with the use of the Synthes 4.5 mm VA-LCP Curved Condylar Plate in acute distal femur fractures, the goal of our study was to examine the outcomes and mechanical failure rates of this implant in a larger patient population.

METHODS

Patients 18 years of age and older who underwent plate fixation of their acute distal femoral fracture using the Synthes 4.5 mm VA-LCP Curved Condylar Plate were included in this retrospective study. The study data was collected through a retrospective chart review and review of the existing radiographic studies. Primary outcome measure was mechanical hardware failure while secondary outcome measures included nonunion, malunion, and medical and surgical complications.

RESULTS

A total of 74 patients (77 fractures) were included in this study. The fractures were classified according to the OTA/AO classification as 33-A2 (n = 6), 33-A3 (n = 19), 33-C1 (n = 5), 33-C2 (n = 25), and 33-C3 (n = 22). Thirty-two out of 77 fractures presented as open fractures (41.6%). A mechanical failure was observed in 7 patients (9.1%). Twenty additional patients needed a re-operation of the surgical site including two nonunion repairs, one malunion repair, 15 staged treatments of traumatic segmental bone defects, and two soft tissue debridements.

CONCLUSIONS

In our experience, the Synthes 4.5 mm VA-LCP Curved Condylar Plate is a safe and effective implant with a relatively low mechanical failure rate.

ORIF With Submuscular Plating of an Intercondylar/Supracondylar Distal Femur Fracture

Fractures of the distal femur with intercondylar extension and comminution are challenging cases and demand a thorough preoperative evaluation and execution of proper surgical technique. Identification of the intra-articular fractures, including coronal fractures of the lateral condyle, is important in planning surgery and emphasizes the need for computerized tomography scans. Recent advances with anatomic, locking plates have made minimally invasive surgery easier, but joint reduction needs to be performed meticulously in an open manner, and restoration of the mechanical alignment through plate fixation is essential for a good clinical outcome. Stable fixation that allows for early range of motion and mobilization are essential for the patient's recovery. This video demonstrates open reduction and internal fixation of a high-energy supracondylar/intercondylar distal femur fracture and emphasizes minimally invasive, biologically friendly techniques.

The Use of Fibular Allograft in Complex Periarticular Fractures Around the Knee

Although the use of fibular strut allografts in proximal humerus fractures has gained popularity, their use in other types of fractures is less well described. Fibular allografts have recently been used in the repair of complex periarticular fractures of the proximal tibia and distal femur. Fibular allografts can be inserted in a variety of manners to achieve goals specific to each individual fracture pattern. In the proximal tibia, insertion through a fracture line or cortical window facilitates joint surface elevation, prevents subsidence and enhances overall construct stability. In distal femoral fractures, including complex periarticular fractures, insertion through the fracture or cortical window permits indirect reduction of the medial cortex and provides necessary medial column support. An additional option in distal femur fractures includes fibula insertion as an intramedullary nail, allowing enhanced fixation in short distal fracture segments. In all cases, the use of a fibular allograft augments poor bone stock and provides improved screw purchase and construct stability when combined with conventional plating methods. Here we present a series of cases at our institution illustrating an array of novel techniques utilizing endosteal fibular allografts in the fixation of complex periarticular fractures about the knee.

Fixation of periprosthetic or osteoporotic distal femoral fractures with locking plates: a pilot randomised controlled trial

Introduction

We hypothesised that the use of a polyaxial locking plate design offers the same clinical benefits as a monoaxial locking plate system following distal femoral osteoporotic/periprosthetic fracture fixation.

Method

A multicentre prospective randomised pilot trial was conducted. Inclusion criteria were patients over 60 years with a displaced osteoporotic or periprosthetic distal femoral fracture. Details documented included time to union, complications, reinterventions and functional outcomes according to the Oxford knee score and EuroQol EQ-5D. Analysis of factors influencing an early fracture healing response was performed between those with clear features of radiological callus formation at three months. Statistical analysis was performed using a logistic regression model with multiple covariates assessed for each plate system (1:1 ratio) over a follow-up period of one year.

Results

Forty patients (34 females) with a mean age of 77 (60–99) were recruited. Four patients deceased within the first six months. Twenty-five patients united by the six month follow-up. Six more patients progressed to union between six and nine months. Five patients developed non-union (two patients had implant failure; one in each group) and all underwent revision surgery. Malunion was evident in two cases, one with 15° of valgus (monoaxial plate), and one with 12° of recurvatum (polyaxial plate). Between the two plate systems, statistical analysis revealed no significant differences in most of the recorded parameters. Radiological features of early bone healing were present when the surgical approach was smaller (p = 0.015), and when a greater working length of the bridging plate was present (p = 0.016).

Conclusion

Both plate systems demonstrated good union rates and limited implant related complications. Good reduction, mechanically sound construct and respect of the local fracture biology was more important than the particular plate design characteristics.

Electronic supplementary material

The online version of this article (10.1007/s00264-018-4061-1) contains supplementary material, which is available to authorized users.

In-vivo stiffness assessment of distal femur fracture locked plating constructs

BACKGROUND

The purpose of this study was to design and validate a novel stiffness-measuring device using locked plating of distal femur fractures as a model.

METHODS

All patients underwent a laterally-based approach, with a bridging locked construct after indirect reduction. A custom and calibrated intraoperative stiffness device was applied and the stiffness of the construct was blindly recorded. Fourteen of twenty-seven patients enrolled with distal femur fractures (AO/OTA 33A and 33C) completed the study. Correlations between stiffness and callus formation, working length, working length/plate length ratio, number of distal locking screws, and fracture pattern were explored.

FINDINGS

Callus and modified radiographic union scale in tibias scores as a linear function of stiffness did not correlate (R2 = 0.06 and 0.07, respectively). Construct working length and working length to plate length ratio did not correlate to stiffness (R2 = 0.18 and 0.16 respectively). A combined delayed and nonunion rate was 14%. Lower extremity measure scores were not statistically different when comparing delayed and nonunion with healed fractures.

INTERPRETATION

The lack of correlation may have been due to the mechanical properties of the plate itself and its large contribution to the overall stiffness of the construct. To our knowledge, clinically relevant stiffness has not been described and this study may provide some estimates. This methodology and these preliminary findings may lay the groundwork for further investigations into this prevalent clinical problem. Other parameters not investigated may play a key role such as body mass index and bone mineral density.

LEVEL OF EVIDENCE

Diagnostic/Prognostic Level II.

Minimally invasive plate osteosynthesis versus conventional open insertion techniques for osteosynthesis

Osteosynthesis has evolved theoretically and practically throughout its evolution. Similar to trends in other surgical fields, surgical techniques in fracture fixation, such as minimally invasive plate osteosynthesis (MIPO), have moved from large dissections to more tissue sparing methods. These plating techniques have been developed for a variety of bones, but more universal clinical adoption will rely upon improved clinical outcomes. The current review will describe minimally invasive techniques, evaluate their rationale, and summarize evidence for their efficacy.

Distal femur: dynamization of plating

With advances in osteosynthesis technology providing improved stability of fixation and better outcomes, surgical treatment has become the standard of care for distal femur fractures. Pre-contoured distal femoral locking plates are the most commonly used implants for fixation. However, healing problems such as delayed union, failure of fixation, and /or nonunion are not uncommon. The fixation construct being "too stiff" is a commonly quoted reason when nonunion/failure of fixation occurs on distal femur fractures fixed with a plate. A flexible fixation construct allowing controlled axial micromotion could help stimulate the bone healing. In order to achieve this goal, plating construct stiffness can be modified by several methods.

Osteoimmunology: Effects of Standard Orthopaedic Interventions on Inflammatory Response and Early Fracture Healing

Achieving fracture union is highly dependent on the initial inflammatory phase of fracture healing, which is influenced by both the local and systemic inflammatory environments. The rapidly emerging field of osteoimmunology involves the study of the interactions between the immune system and the skeletal system. Recent research has advanced the current state of knowledge regarding the effects of the surrounding soft-tissue injury, fracture hematoma, and the method of fracture fixation on the inflammatory phase of fracture healing. Acute systemic inflammation, as seen in patients with polytrauma, and chronic systemic inflammation, as seen in patients with diabetes or rheumatoid arthritis, affects the inflammatory phase of fracture healing. The use of NSAIDs can influence early fracture healing. Understanding the effects of standard orthopaedic interventions on the local and systemic inflammatory responses and early fracture healing is important for optimizing fracture union.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Biologically synthesized titanium oxide nanostructures combined with morphogenetic protein as wound healing agent in the femoral fracture after surgery

The aim of the present study is to develop novel approach for the green synthesis of titanium oxide nanoparticles (TiO₂ NPs) using Eichhornia crassipes extract and calcined at different temperatures for evaluate the wound healing activity in the femoral fracture. The synthesized TiO₂ are formed different (plate and rod-like) nanostructures at various calcination temperatures. These samples were characterized by X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), Field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM). Microscopic studies of TiO₂ NPs revealed that the synthesized TiO₂ NPs are formed well-defined rod-like structures at 400 °C with size ranged from 200 nm to 500 nm. The characterized plate and rod-like TiO₂ NPs are combined with human morphogenetic protein (HbMP) to improving its wound healing activity and osteoblast properties on femoral fractures. The biocompatibility was tested by using human bone marrow mesenchymal stem cells (BMSC) cells and antibacterial efficacy analyzed using human pathogenica bacteria Staphylococcus aureus and Escherichia coli through agar well diffusion assay. The green synthesized rod-like TiO₂ NPs combined with HbMP has been exhibited effective bone fusion behaviors with biomechanical properties and also improved antibacterial activity against pathogenic bacteria. From this study results, it is suggested that green synthesized TiO₂NPs could be used effectively in biomedical application.

Endosteal Substitution With an Intramedullary Rod in Fractures of the Femur

BACKGROUND

Morbid obesity and segmental fracture/bone loss are challenging problems in the treatment of fractures and nonunions of the distal femur. The use of an intramedullary rod as an endosteal substitute for a deficient medial cortex along with a lateral locked plate is 1-tool to combat these problems. This article describes the technique used and its results at a single Level 1 trauma center.

METHODS

Retrospective chart and radiographic review of all patients treated for acute fractures and nonunions of the distal femur using endosteal substitution with an intramedullary nail and a lateral locked plate. Fixation construct was determined at the surgeon's discretion and was strongly influenced by bone loss and patient body habitus.

RESULTS

Seven of 8 acute fractures and 8 of 8 nonunions healed without an unplanned reoperation. There were no cases of secondary displacement after fixation, and only 1 unplanned reoperation in the study group.

CONCLUSION

Endosteal substitution with an intramedullary rod and the use of a lateral locked plate provides the stability needed to allow bone healing under prolonged or supraphysiologic loads seen in morbid obesity or segmental bone loss.

LEVEL OF EVIDENCE

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

Diabetes and Healing Outcomes in Lower Extremity Fractures: A Systematic Review

OBJECTIVE

The purpose of this study was to review the rates of adverse healing outcomes following surgical fixation of lower extremity fractures in diabetic patients and matched controls.

MATERIALS AND METHODS

Searches of PubMed, MEDLINE, CINAHL and Embase were performed for studies published between the date of database inception and July 6, 2015. Patient characteristics and the incidence of adverse healing outcomes (nonunion, malunion, delayed union, infection and reoperation) were extracted from each study. The occurrence of each fracture healing complication was pooled and analyzed for comparisons between diabetic and non-diabetic patients. An odds ratio with a 95% confidence interval for each healing outcome was calculated between the diabetic and non-diabetic groups.

RESULTS

Diabetes was found to significantly increase rates of malunion, infection and reoperation in patients with surgically treated lower extremity fractures. In addition, when only peripheral lower extremity fractures (i.e. below the knee) were examined, diabetes significantly increased the rates of nonunion.

CONCLUSION

Diabetes substantially alters bone metabolism and soft tissue healing, posing a risk of adverse fracture healing and other complications. This systematic review provides evidence that the presence of diabetes significantly increases the risks of infection, malunion, nonunion and re-operation across a wide variety of surgically treated lower extremity fractures. This study provides prognostic information for clinicians and may aid in guiding treatment for this population.

[Flexible internal fixation with locking plate for distal femoral fractures]

Objective

To analyze the effectiveness of flexible internal fixation with locking plate for distal femoral fractures.

Methods

Between January 2015 and June 2016, 21 cases of distal femoral fractures were treated. There were 5 males and 16 females with an average age of 62 years (range, 32-88 years). Injury was caused by falling in 14 cases, by traffic accident in 5 cases, and by falling from height in 2 cases. The fractures located at the left side in 13 cases and the right side in 8 cases. Twenty cases were fresh closed fractures and 1 case was open fracture. According to AO/Association for the Study of Internal Fixation (AO/OTA) typing, there were 5 cases of type 33-A1, 3 of type 33-A2, 8 of type 33-A3, 2 of type 33-C2, and 3 of type 33-C3. The time from injury to operation was 3-13 days (mean, 6.5 days).

Results

All operation incisions healed primarily. Eighteen patients were followed up 12-24 months (mean, 16 months). All fractures healed, and the healing time was 8-24 weeks (mean, 16.6 weeks). The articular surface was smooth and the thigh length was recovered. No screw loosening, plate breakage, valgus or varus of the knee, stiff of the knee or non-unions occurred during follow-up. There was no significant difference in visual analogue scale (VAS) score between at 6 and 12 months after operation ( P>0.05), and the difference was significant bewteen the other time points ( P<0.05). There were significant differences in the range of motion of knee between 1 month and 3, 6, 12 months ( P<0.05); there was no significant difference between 3, 6, and 12 months ( P>0.05). There were significant differences in the Neer scores between 1, 3, 6, and 12 months after operation ( P<0.05). According to Neer score criteria, the results were excellent in 12 cases and good in 6 cases at 12 months after operation.

Conclusion

Flexible internal fixation with locking plate for distal femoral fractures can get good functional recovery.

Percutaneous Application of a Medial Plate for Dual Plate Stabilization of Supracondylar Femur Fractures

Supracondylar femur fractures with segmental defects can be difficult fractures to treat. When associated with open wounds, these injuries can be associated with numerous complications including nonunion, malunion, infection, and arthrofibrosis. In this article, we review our algorithm for treating these fractures and highlight critical aspects of the process which differs from previous techniques described. We feel that this technique has specific benefits that mitigate infection risk and minimize additional soft-tissue insult without compromising stability. Our results demonstrate good postoperative knee range of motion, a high union rate, with low complication rates.

Proximal Screw Configuration Alters Peak Plate Strain Without Changing Construct Stiffness in Comminuted Supracondylar Femur Fractures

OBJECTIVES

Assess the effect of proximal screw configuration on the strain in lateral plating of a simulated comminuted supracondylar femur fracture.

METHODS

Fractures were simulated in 12 synthetic femurs by removing a 200-mm section of bone, located 60 mm from the intercondylar fossa and repaired using a 16-hole locked lateral plate instrumented with 8 uniaxial strain gauges. Three proximal screw type configurations were evaluated: (1) 4 nonlocking screws, (2) 4 locking screws, and (3) a hybrid configuration of 2 nonlocking screws flanked by a locking screw at each end of the proximal fragment. Each screw type was compared for 2 working lengths (∼90 and 160 mm). The longer working length was created by removing the proximal screw closest to the fracture gap. Testing consisted of a vertical load (500 N) applied to the head of femur. Configurations were compared using plate strain, construct stiffness, and fracture gap displacement as outcome measures.

RESULTS

Plate strain immediately above the fracture gap was reduced with nonlocking screws compared with the other screw types. Plate strains were reduced around the fracture gap with the longer working length but increased for the nonlocking construct at the location of the removed screw. Construct stiffness was not altered by screw type or working length. An increase in fracture gap displacement was only evident in shear translation with the longer working length.

CONCLUSIONS

Plate strain in lateral plating of supracondylar femur fractures is decreased using nonlocking screws proximal to the fracture. Increasing the working length reduces plate strains over the working length yet should be cautioned because of increased interfragmentary shear motion.

Working length and proximal screw constructs in plate osteosynthesis of distal femur fractures

BACKGROUND

The study purpose is to evaluate the working length, proximal screw density, and diaphyseal fixation mode and the correlation to fracture union after locking plate osteosynthesis of distal femoral fractures using bridge-plating technique.

METHODS

A four-year retrospective review was performed to identify patients undergoing operative fixation of distal femur fractures with a distal femoral locking plate using bridge-plating technique for the metadiaphyseal region. Primary variables included fracture union, secondary surgery for union, plate working length, and diaphyseal screw technique and configuration. Multiple secondary variables including plate metallurgy and coronal plane fracture alignment were also collected.

RESULTS

Ninety-six patients with distal femur fractures with a mean age 60 years met inclusion criteria. None of the clinical parameters were statistically significant indicators of union. Likewise, none of the following surgical technique parameters were associated with fracture union: plate metallurgy, the mean working length, screw density and number of proximal screws and screw cortices. However, diaphyseal screw technique did show statistical significance. Hybrid technique had a statistically significant higher chance of union when compared to locking (p=0.02). All proximal locking screw constructs were 2.9 times more likely to lead to nonunion.

CONCLUSIONS

Plating constructs with all locking screws used in the diaphysis when bridge-plating distal femur locking plates were 2.9 times more likely to incur a nonunion. However, other factors associated with more flexible fixation constructs such as increased working length, decreased proximal screw number, and decreased proximal screw density were not significantly associated with union in this study.

Risk Factors for Failure of Bone Grafting of Tibia Nonunions and Segmental Bone Defects: A New Preoperative Risk Assessment Score

OBJECTIVE

To develop a clinically useful prediction model of success at the time of surgery to promote bone healing for established tibial nonunion or traumatic bone defects.

DESIGN

Retrospective case controlled.

SETTING

Level 1 trauma center.

PATIENTS

Adult patients treated with surgery for established tibia fracture nonunion or traumatic bone defects from 2007 to 2016. Two hundred three patients met the inclusion criteria and were available for final analysis.

INTERVENTION

Surgery to promote bone healing of established tibia fracture nonunion or segmental defect with plate and screw construct, intramedullary nail fixation, or multiplanar external fixation.

MAIN OUTCOME MEASURES

Failure of the surgery to promote bone healing that was defined as unplanned revision surgery for lack of bone healing or deep infection. No patients were excluded who had a primary outcome event.

RESULTS

Multivariate logistic modeling identified 5 significant (P < 0.05) risk factors for failure of the surgery to promote bone healing: (1) mechanism of injury, (2) Increasing body mass index, (3) cortical defect size (mm), (4) flap size (cm), and (5) insurance status. A prediction model was created based on these factors and awarded 0 points for fall, 17 points for high energy blunt trauma (OR = 17; 95% CI, 1-286, P = 0.05), 22 points for industrial/other (OR = 22; 95% CI, 1-4, P = 0.04), and 28 points for ballistic injuries (OR = 28; 95% CI, 1-605, P = 0.04). One point is given for every 10 cm of flap size (OR = 1; 95% CI, 1-1.1, P < 0.001), 10 mm of mean cortical gap distance (OR = 1; 95% CI, 1-2, P = 0.004), and 10 units BMI, respectively (OR = 1.5; 95% CI, 1-3, P = 0.16). Two points are awarded for Medicaid or no insurance (OR = 2; 95% CI, 1-5, P = 0.035) and 3 points for Medicare (3; 95% CI, 1-9, P = 0.033). Each 1-point increase in risk score was associated with a 6% increased chance of requiring at least 1 revision surgery (P < 0.001).

CONCLUSIONS

This study presents a clinical score that predicts the likelihood of success after surgery for tibia fracture nonunions or traumatic bone defects and may help clinicians better determine which patients are likely to fail these procedures and require further surgery.

A double-plating approach to distal femur fracture: A clinical study

BACKGROUND

Locked plating is one of the latest innovative options for treating supracondylar femur fractures with relatively low failure rates. Single lateral plating was often found to have a relative higher failure rate. No clinical studies of double-plating distal femur fixation have thus far been reported. The aim of this study is to present our clinical experience with this surgical approach.

PATIENTS AND METHODS

Thirty-two patients (26 females and 6 males, mean age 76 years, range 44-101) were included in the study. Eight of them patients had a periprosthetic stable implant fracture and two patients were treated for a nonunion.

RESULTS

All fractures, excluding one that needed bone grafting and one refracture, healed within 12 weeks. One patient needed bone grafting for delayed union and one patient needed fixation exchange due to femur re-fracture at the site of the most proximal screw. Two patients developed superficial wound infection and one patient required medial plate removal after union due to deep infection.

CONCLUSIONS

Based on these promising results, we propose that the double-plating technique should be considered in the surgeon's armamentarium for the treatment of supracondylar femur fractures, particularly in patients with poor bone quality, comminuted fractures and very low periprosthetic fractures.

Open Supracondylar-Intercondylar Fractures of the Femur Treatment With Taylor Spatial Frame

OBJECTIVES

To evaluate the Taylor spatial frame (TSF) for primary and definitive fixation of open supracondylar-intracondylar femoral (SIF) fractures.

DESIGN

Retrospective.

SETTING

Level I trauma center.

PATIENTS

Subset of 20 SIF open fractures treated with TSF extracted from a consecutive series of 80 SIF fractures treated between 2007 and 2013.

INTERVENTION

Eighteen (90%) fractures underwent definitive fixation with the TSF; 2 were treated primarily within 24 hours of injury. Mean time interval between primary treatment and secondary TSF was 5 days.

MAIN OUTCOME MEASUREMENTS

Clinical and radiological.

RESULTS

Complete union was obtained in 17 (85%) fractures without additional surgery at an average of 33 weeks. Three nonunions and 1 malunion occurred. No deep infection occurred. Results based on Association for the Study and Application of the Method of Ilizarov criteria: 37% excellent, and 63% good for bone outcomes; 5% excellent, 58% good, and 37% fair for functional outcomes. Neer knee scores were 21% excellent, 68% good, and 11% fair. The mechanical lateral distal femoral angle and anatomic posterior distal femoral angle values were within normal range in 80% and 90% of patients, respectively. Abnormal mechanical axis deviation was observed in 4 (20%) cases (2 had associated tibia fractures).

CONCLUSIONS

Primary and definitive fixation with the TSF are effective. Advantages include continuity of device until union, reduced risk of infection, early mobilization, restoration of primary defect caused by bone loss, easy and accurate application, convertibility and versatility, and improved union rate and range of motion for SIF open fractures.

LEVEL OF EVIDENCE

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