Distal femoral fractures: long-term outcome following stabilisation with the LISS

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%.

Radiographic Union Assessment in Surgically Treated Distal Femur Fractures: A Systematic Review

BACKGROUND

Distal femur fractures are known to have challenging nonunion rates. Despite various available treatment methods aimed to improve union, optimal interventions are yet to be determined. Importantly, there remains no standard agreement on what defines radiographic union. Although various proposed criteria of defining radiographic union exist in the literature, there is no clear consensus on which criteria provide the most precise measurement. The use of inconsistent measures of fracture healing between studies can be problematic and limits their generalizability. Therefore, this systematic review aims to identify how fracture union is defined based on radiographic parameters for surgically treated distal femur fractures in current literature.

METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Medline, EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science Core Collection databases were searched from inception to October 2022. Studies that addressed surgically treated distal femur fractures with reported radiographic union assessment were included. Outcomes extracted included radiographic definition of union; any testing of validity, reliability, or responsiveness; reported union rate; reported time to fracture union; and any functional outcomes correlated with radiographic union.

RESULTS

Sixty articles with 3,050 operatively treated distal femur fractures were included. Operative interventions included lateral locked plate (42 studies), intramedullary nail (15 studies), dynamic condylar screw or blade plate (7 studies), dual plate or plate and nail construct (5 studies), distal anterior-posterior/posterior-anterior screws (1 study), and external fixation with a circular frame (1 study). The range of mean follow-up time reported was 4.3 to 44 months. The most common definitions of fracture union included "bridging or callus formation across 3 of 4 cortices" in 26 (43%) studies, "bony bridging of cortices" in 21 (35%) studies, and "complete bridging of cortices" in 9 (15%) studies. Two studies included additional assessment of radiographic union using the Radiographic Union Scale in Tibial fracture (RUST) or modified Radiographic Union Scale in Tibial fracture (mRUST) scores. One study included description of validity, and the other study included reliability testing. The reported mean union rate of distal femur fractures was 89% (range 58%-100%). The mean time to fracture union was documented in 49 studies and found to be 18 weeks (range 12-36 weeks) in 2,441 cases. No studies reported correlations between functional outcomes and radiographic parameters.

CONCLUSION

The current literature evaluating surgically treated distal femur fractures lacks consistent definition of radiographic fracture union, and the appropriate time point to make this judgement is unclear. To advance surgical optimization, it is necessary that future research uses validated, reliable, and continuous measures of radiographic bone healing and correlation with functional outcomes.

LEVEL OF EVIDENCE

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

The double-plate fixation technique prevents varus collapse in AO type C3 supra-intercondylar fracture of the distal femur

INTRODUCTION

Varus collapse followed by osteosynthesis for distal femoral fractures with conventional implants has been well documented but is seldom mentioned in fractures managed with locking plates. The purpose of this study was to assess the incidence of varus collapse after treating complex supra-intercondylar fractures of the distal femur (AO type C3) using a Single Plate (SP) or Double Plate (DP) fixation technique.

MATERIALS AND METHODS

We retrospectively reviewed 357 patients with distal femoral fractures who were treated at our hospital between 2006 and 2017. After excluding cases of infection, malignancy, periprosthetic fracture, revision surgery, pediatric fracture, and extra-articular fracture, 54 patients were included in the study. All demographic data and radiological and clinical outcomes were reviewed and analyzed.

RESULTS

There were 54 patients enrolled into this study with age from 15 to 85 years old (mean 41.6, SD = 19.9), and 32 of them were open fractures (59%). The patients were further divided into either an SP (n = 15) or a DP group (n = 39). Demographics, including age, sex, injury severity score, and open fracture type, were all compatible between the two groups. The overall nonunion rate was 25.9% (n = 14; 6 from the SP and 8 from the DP group; p = 0.175). The varus collapse rate was 9.3% (n = 5; 4 from the SP and 1 from the DP group (p = 0.018).

CONCLUSIONS

The varus collapse rate after osteosynthesis with a single lateral locking plate could be as high as 26.7% in AO type C3 fractures of the distal femur, which would be decreased to 2.6% by adding a medial buttress plate. Surgeons should consider DP fixation to avoid varus collapse in severely comminuted complete intra-articular fractures of the distal femur.

Locked Lateral Plating Versus Retrograde Nailing for Distal Femur Fractures: A Multicenter Randomized Trial

OBJECTIVES

The 2 main forms of treatment for distal femur fractures are locked lateral plating and retrograde nailing. The goal of this trial was to determine whether there are significant differences in outcomes between these forms of treatment.

DESIGN

Multicenter randomized controlled trial.

SETTING

Twenty academic trauma centers.

PATIENTS/PARTICIPANTS

One hundred sixty patients with distal femur fractures were enrolled. One hundred twenty-six patients were followed 12 months. Patients were randomized to plating in 62 cases and intramedullary nailing in 64 cases.

INTERVENTION

Lateral locked plating or retrograde intramedullary nailing.

MAIN OUTCOME MEASUREMENTS

Functional scoring including Short Musculoskeletal Functional Assessment, bother index, EQ Health, and EQ Index. Secondary measures included alignment, operative time, range of motion, union rate, walking ability, ability to manage stairs, and number and type of adverse events.

RESULTS

Functional testing showed no difference between the groups. Both groups were still significantly affected by their fracture 12 months after injury. There was more coronal plane valgus in the plating group, which approached statistical significance. Range of motion, walking ability, and ability to manage stairs were similar between the groups. Rate and type of adverse events were not statistically different between the groups.

CONCLUSIONS

Both lateral locked plating and retrograde intramedullary nailing are reasonable surgical options for these fractures. Patients continue to improve over the course of the year after injury but remain impaired 1 year postoperatively.

LEVEL OF EVIDENCE

Therapeutic Level I. 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.

Safe and dangerous zones for the superficial femoral artery in femoral surgery

The proximity of the superficial femoral artery (SFA) to the femur exposes the SFA to risks that have serious complications. Although surgeons have used the lateral or medial approach to lessen these risks, they have not been eliminated. Therefore, this study aimed to identify dangerous and safe zones in terms of the SFA that can be used during femoral surgical procedures, using anatomical reference points. Computed tomography angiography (CTA) of 50 patients aged between 16 and 60 years obtained from the local institution's database was examined. Radiological and clinical measurements were performed to determine the position of the SFA relative to the femur. The mean age of the patients included in this study was 38.08 ± 9.44 (16-60) years. The average ratio of the distance between the proximal and distal borders of the dangerous zone and the lateral joint spaces (LJS) to the distance between the greater trochanter (GT) and LJS was 0.5722 ± 0.053, respectively. The average ratio of the distance between the end of the dangerous zone and LJS to the distance between the GT and LJS was 0.4108 ± 0.05026. This study found that 40% and 60% of the clinically measured distance between the GT and LJS can be used to determine safe and dangerous zones during femoral surgery. Additionally, the half distance between the anterior superior iliac spine (ASIS) and medial joint space (MJS) and one-fourth of the distance between the ASIS and LJS can be used to determine safe and dangerous zones in patients whose GT are not easily palpated.

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.

Spatio-temporal characterization of fracture healing patterns and assessment of biomaterials by time-lapsed in vivo micro-computed tomography

Thorough preclinical evaluation of functionalized biomaterials for treatment of large bone defects is essential prior to clinical application. Using in vivo micro-computed tomography (micro-CT) and mouse femoral defect models with different defect sizes, we were able to detect spatio-temporal healing patterns indicative of physiological and impaired healing in three defect sub-volumes and the adjacent cortex. The time-lapsed in vivo micro-CT-based approach was then applied to evaluate the bone regeneration potential of functionalized biomaterials using collagen and bone morphogenetic protein (BMP-2). Both collagen and BMP-2 treatment led to distinct changes in bone turnover in the different healing phases. Despite increased periosteal bone formation, 87.5% of the defects treated with collagen scaffolds resulted in non-unions. Additional BMP-2 application significantly accelerated the healing process and increased the union rate to 100%. This study further shows potential of time-lapsed in vivo micro-CT for capturing spatio-temporal deviations preceding non-union formation and how this can be prevented by application of functionalized biomaterials. This study therefore supports the application of longitudinal in vivo micro-CT for discrimination of normal and disturbed healing patterns and for the spatio-temporal characterization of the bone regeneration capacity of functionalized biomaterials.

In Vitro Macrophage Immunomodulation by Poly(ε-caprolactone) Based-Coated AZ31 Mg Alloy

Due to its excellent bone-like mechanical properties and non-toxicity, magnesium (Mg) and its alloys have attracted great interest as biomaterials for orthopaedic applications. However, their fast degradation rate in physiological environments leads to an acute inflammatory response, restricting their use as biodegradable metallic implants. Endowing Mg-based biomaterials with immunomodulatory properties can help trigger a desired immune response capable of supporting a favorable healing process. In this study, electrospun poly(ε-caprolactone) (PCL) fibers loaded with coumarin (CM) and/or zinc oxide nanoparticles (ZnO) were used to coat the commercial AZ31 Mg alloy as single and combined formulas, and their effects on the macrophage inflammatory response and osteoclastogenic process were investigated by indirect contact studies. Likewise, the capacity of the analyzed samples to generate reactive oxygen species (ROS) has been investigated. The data obtained by attenuated total reflection Fourier-transform infrared (FTIR-ATR) and X-ray photoelectron spectroscopy (XPS) analyses indicate that AZ31 alloy was perfectly coated with the PCL fibers loaded with CM and ZnO, which had an important influence on tuning the release of the active ingredient. Furthermore, in terms of degradation in phosphate-buffered saline (PBS) solution, the PCL-ZnO- and secondary PCL-CM-ZnO-coated samples exhibited the best corrosion behaviour. The in vitro results showed the PCL-CM-ZnO and, to a lower extent, PCL-ZnO coated sample exhibited the best behaviour in terms of inflammatory response and receptor activator of nuclear factor kappa-B ligand (RANKL)-mediated differentiation of RAW 264.7 macrophages into osteoclasts. Altogether, the results obtained suggest that the coating of Mg alloys with fibrous PCL containing CM and/or ZnO can constitute a feasible strategy for biomedical applications.

Distal Femur Replacement Versus Surgical Fixation for the Treatment of Geriatric Distal Femur Fractures: A Systematic Review

OBJECTIVES

The management of geriatric distal femur fractures is controversial, and both primary distal femur replacement (DFR) and surgical fixation (SF) are viable treatment options. The purpose of this study was to compare patient outcomes after these treatment strategies.

DATA SOURCES

PubMed, Embase, and Cochrane databases were searched for English language articles up to April 24, 2020, identifying 2129 papers.

STUDY SELECTION

Studies evaluating complications in elderly patients treated for distal femur fractures with either immediate DFR or SF were included. Studies with mean patient age <55 years, nontraumatic indications for DFR, or SF with nonlocking plates were excluded.

DATA EXTRACTION

Two studies provided Level II or III evidence, whereas the remaining 28 studies provided Level IV evidence. Studies were formally evaluated for methodological quality using established criteria. Treatment failure between groups was compared using an incidence rate ratio.

DATA SYNTHESIS

Treatment failure was defined for both SF and arthroplasty as complications requiring a major reoperation for reasons such as mechanical failure, nonunion, deep infection, aseptic loosening, or extensor mechanism disruption. There were no significant differences in complication rates or knee range of motion between SF and DFR.

CONCLUSIONS

SF and DFR for the treatment of geriatric distal femur fractures demonstrate similar overall complication rates. Given the available evidence, no strong conclusions on the comparative effectiveness between the 2 treatments can be definitively made. More rigorous prospective research comparing SF vs. DFR to treat acute geriatric distal femur fractures is warranted.

LEVEL OF EVIDENCE

Therapeutic Level IV. See instructions for authors for a complete description of levels of evidence.

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.

Locking plate fixation versus antegrade intramedullary nailing for the treatment of extra-articular distal femoral fractures

INTRODUCTION

The current study aimed to retrospectively analyze locked plating (LP) and antegrade intramedullary nailing (AIN) for the treatment of extra-articular distal femoral fractures.

PATIENTS AND METHODS

Between January 2000 and March 2015, 97 patients (49 male, 48 female) underwent surgery for extra-articular distal femoral fractures in our clinic. Patients were grouped based on their method of treatment (69 (71.1%) with locked plate (LP group) and 28 (28.9%) with antegrade intramedullary nailing (AIN group)), and the groups were analyzed with regards to fracture types, associated trauma, hospital stay, Injury Severity Score (ISS), nonunion, reoperation rate and Lysholm Functional Knee Score.

RESULTS

The LP and AIN groups had no significant differences with regards to age and gender. Sixteen patients (16.4%) experienced nonunion; all of these (5 (5.1%) in the AIN group and 11 (11.3%) in the LP group) required a secondary procedure (p = 0.773). ISS was significantly higher in the AIN group (p = 0.033). There were no significant differences between the two groups with regards to hardware failure, postoperative malreduction, reoperation rate, deep infection, and nonunion. However, the AIN group (mean 88) had a significantly higher Lysholm Functional Knee Score than the LP group (mean 75.9) (p = 0.019).

CONCLUSION

In our study we encountered less nonunion in AIN group. Both fixation methods offer good results; however, functional outcomes in the AIN group were significantly better than those in the LP group.

Primary ilizarov external fixation in open grade III type C distal femur fractures: Our experience

INTRODUCTION

Open comminuted distal femur fractures are notorious for septic or aseptic non-union. The recommended fixed angle distal femur locking plate in such situations can lead to a septic non-union due to its extensive approach and further periosteal stripping. Supracondylar nails, though have a minimally invasive approach, are not suitable for type C2 and C3 (AO/ASIF) fractures. A monolateral fixator as damage control followed by plating may be recommended. But if wound healing is delayed it results in difficult articular reduction, poor alignment and a stiff knee. We therefore used ilizarov circular external fixators (ICEF) for such open fractures (type C1, C2 and C3) and analysed its radiological and functional outcomes.

MATERIALS AND METHODS

25 male patients, with a mean age of 31.04 ± 6.62 years (range, 22-44 years), with open grade III type C distal femoral fractures were treated with ICEF. There were 7 fractures of type C1and C3 each, 11 were of type C2. Articular reduction and compression was achieved with inter-fragmentary screws through minimal open technique by extending the open wound and then stabilising the fracture with ICEF. The main outcomes evaluated were union, range of motion, final shortening, Knee Society scoring and ASAMI scoring system for radiological and functional outcomes.

RESULTS

The mean follow-up period was 19.12 ± 1.14 months. All fractures except two united at a mean period of 30 ± 3.02 weeks, without the need of bone grafts. The bony assessment (according to ASAMI score) was excellent in 8 cases (33.33%), good in 9 cases (37.5%) and fair in 5 cases (20.83%), while there were 2 poor clinical end results. The functional results were excellent in 6 cases (25%), good in 9 cases (37.5%) fair in 6 cases (25%) poor in 3 cases (12.5%). The complications included shortening, extension lag and pin tract infections.

CONCLUSION

With the encouraging results, the use of ICEF with minimal internal fixation in grade III open comminuted distal femur fractures as a primary definitive treatment is a valuable alternative.

Modulation of Osteoclast Interactions with Orthopaedic Biomaterials

Biomaterial integration in bone depends on bone remodelling at the bone-implant interface. Optimal balance of bone resorption by osteoclasts and bone deposition by osteoblasts is crucial for successful implantation, especially in orthopaedic surgery. Most studies examined osteoblast differentiation on biomaterials, yet few research has been conducted to explore the effect of different orthopaedic implants on osteoclast development. This review covers, in detail, the biology of osteoclasts, in vitro models of osteoclasts, and modulation of osteoclast activity by different implant surfaces, bio-ceramics, and polymers. Studies show that surface topography influence osteoclastogenesis. For instance, metal implants with rough surfaces enhanced osteoclast activity, while smooth surfaces resulted in poor osteoclast differentiation. In addition, surface modification of implants with anti-osteoporotic drug further decreased osteoclast activity. In bioceramics, osteoclast development depended on different chemical compositions. Strontium-incorporated bioceramics decreased osteoclast development, whereas higher concentrations of silica enhanced osteoclast activity. Differences between natural and synthetic polymers also modulated osteoclastogenesis. Physiochemical properties of implants affect osteoclast activity. Hence, understanding osteoclast biology and its response to the natural microarchitecture of bone are indispensable to design suitable implant interfaces and scaffolds, which will stimulate osteoclasts in ways similar to that of native bone.

Any Cortical Bridging Predicts Healing of Supracondylar Femur Fractures After Treatment With Locked Plating

OBJECTIVES

To determine the accuracy and reliability of radiographic cortical bridging criteria in predicting the final healing of supracondylar femur fractures after treatment with locked plating.

DESIGN

Retrospective review.

SETTING

Two Level 1 trauma centers.

PATIENTS/PARTICIPANTS

Patients who presented with supracondylar femur fractures (OTA/AO 33A, C) and were treated with locking plate fixation between January 1, 2004, and January 1, 2011. The final study population included 82 fractures after excluding patients with open physes (n = 4), nondisplaced fractures (n = 4), early revision for technical failure (n = 4), or inadequate follow-up (n = 42).

INTERVENTION

Distal femur locking plate fixation.

MAIN OUTCOME MEASUREMENTS

Postoperative radiographs until final follow-up were assessed for cortical bridging at each cortex on anterior-posterior and lateral views. Images were analyzed independently by 3 orthopaedic traumatologists to allow for assessment of reliability. Final determination of union required both radiographic and clinical confirmation.

RESULTS

Assessment for any cortical bridging was the earliest accurate predictor of final union (95.1% accuracy at 4 months postoperatively), compared with criteria requiring bicortical bridging (93.9% accuracy at 6 months) and tricortical bridging (78% accuracy at 21 months). Any cortical bridging demonstrated a higher interobserver reliability (kappa = 0.73) relative to bicortical (kappa = 0.27) or tricortical bridging (kappa = 0.5).

CONCLUSIONS

Our results for plate fixation of supracondylar distal femur fractures mirror those previously described for intramedullary nailing of tibia shaft fractures. Any radiographic cortical bridging by 4 months postoperatively is an accurate and reliable predictor of final healing outcome after locking plate fixation of supracondylar femur fractures. Assessment for bicortical or tricortical bridging is less reliable and inaccurate during the first postoperative year.

LEVEL OF EVIDENCE

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

Treatment of Distal Femur Nonunion Following Initial Fixation with a Lateral Locking Plate

OBJECTIVE

To report and evaluate the outcomes of patients undergoing definitive treatment for distal femur nonunion after initial treatment with a locking plate.

METHODS

Fourteen patients who had undergone definitive treatment at an academic Level 1 trauma center from May 2007 to December 2013 for distal femur nonunion were identified from a fracture database. Thirteen of them were female; the average age was 65 years (range, 50-84 years). Ten patients had sustained their injuries in falls at ground level, and four in motor vehicle accidents. Twelve patients were obese (body mass index ≥30), 10 had diabetes, none were current smokers, and one had an open fracture classified as type IIIa according to the Gustilo-Anderson classification system for open fractures. The fractures were classified according to the AO classification system for distal femur fractures; there were three type 33-A1, six 33-A2, two 33-A3 and three 33-C3 fractures. Methods of definitive treatment involved open reduction and internal fixation (ORIF) revision, medial plating, bone grafting and the use of other biologic materials.

RESULTS

Eight of the 14 patients (57%) achieved union during follow-up. Definitive treatment for nonunion involved ORIF revision in 11 cases. Three patients who did not undergo ORIF revision were treated with iliac crest stem cell autografts, bone graft substitutes or recombinant human-bone morphogenetic protein-2 (rh-BMP-2). Other treatments included rh-BMP-2 (12 cases), iliac crest bone autograft (five), iliac crest stem cell autograft (two), crushed cancellous bone allograft (three), CaSO 4 and tricalcium phosphate bone graft substitute (two) and demineralized bone matrix (one). The average time from definitive treatment to union was 19 weeks (range, 12-51 weeks). Two of the 11 cases who underwent ORIF revision had medial plates added to improve biomechanical stability and prevent varus collapse. This was also performed in one patient with a grade III open type 33-C3 fracture and one with a closed 33-A2 fracture. Five study patients had comminuted fractures. Two had type 33-A3 and three type 33-C3 fractures. Both patients with 33-A3 fractures and 2 two with 33-C3 fractures had persistent nonunion at the end of follow-up.

CONCLUSIONS

Definitive treatment of distal femur nonunion after initial treatment with a locking plate had a low rate of success in this study, suggesting that this procedure is ineffective as a definitive treatment for distal femur nonunion.

Application of calcium phosphates and fibronectin as complementary treatment for osteoporotic bone fractures

INTRODUCTION

The gradual aging of the population results in increased incidence of osteoporotic bone fractures. In a good quality bone, the fixation with the usual methods is adequate, but not in osteoporotic bone, in which consolidation delays and other complications are common, with failure rates for screws up to 25%.

OBJECTIVE

To test fibronectin loaded hydroxyapatite as a complementary treatment for osteoporotic fractures.

MATERIAL AND METHODS

This study was performed in a vivo model; 42 female osteoporotic adult rabbits 4-5kg (White New Zealand) were used. Two groups (hydroxyapatite and fibronectin loaded hydroxyapatite) and a control group were tested. 3 time points 24h, 48h and 5days were studied. Defects were created in both femurs, in one of them, a cannulated screw (4mm) and a biocompatible material were placed; in the other femur a screw was inserted without supplemented material forming the control group. Osteoporosis was induced from models already known throughout administration of steroids. Samples were analyzed histologically and through imaging (micro Ct).

RESULTS

Basal levels of BMD are observed below to normal when compared to other studies (0.25/0.3 instead of 0.4). Global and dependent of time analysis of samples, show no significant differences for samples analyzed. However, an important trend was noted for variables that define the trabecular bone microarchitecture. Indices that define trabecular microarchitecture in the comparative analysis found to have statistical differences (p<0.01).

DISCUSSION

Osteosynthesis in an osteoporotic bone is a challenge for the surgeon, due to a reduced bone mineral density and different bone architecture. The main finding was the verification of the hypothesis that the trabecular bone parameters increases with our augmentation material in weak rabbit bone quality. Also, the histological analyses of samples show an increase of non inflammatory cells in protein samples (OHAp-Fn) from the first 24hours.

CONCLUSION

An early response of rabbit osteroporotic bone to a complementary treatment with fibronectin loaded hydroxyapatite has been observed. This response is reflected in greater values for indices that define the trabecular bone microarchitecture, thickness and separation, a greater non-inflammatory cellularity after only 24hours and an increased amount of connective tissue observed at 48hours.

Fixation of supraglenoid tubercle fractures using distal femoral locking plates in three Warmblood horses

Three horses that were presented with supraglenoid tubercle fractures were treated with open reduction and internal fixation using distal femoral locking plates (DFLP). Placing the DFLP caudal to the scapular spine in order to preserve the suprascapular nerve led to a stable fixation, however, it resulted in infraspinatus muscle atrophy and mild scapulohumeral joint instability (case 1). Placing the DFLP cranial to the scapular spine and under the suprascapular nerve resulted in a stable fixation, however, it resulted in severe atrophy of the supraspinatus and infraspinatus muscles and scapulohumeral joint instability (case 2). Placing the DFLP cranial to the scapular spine and slightly overbending it at the suprascapular nerve passage site resulted in the best outcome (case 3). Only a mild degree of supraspinatus and infraspinatus muscle atrophy was apparent, which resolved quickly and with no effect on scapulohumeral joint stability. In all cases, fixation of supraglenoid tubercle fractures using DFLP in slightly different techniques led to stable fixations with good long-term outcome. One case suffered from a mild incisional infection and plates were removed in two horses. Placement of the DFLP cranial to the scapular spine and slightly overbending it at the suprascapular nerve passage prevented major nerve damage. Further cases investigating the degree of muscle atrophy following the use of the DFLP placed in the above-described technique are justified to improve patient outcome.

The outcome of Polyax Locked Plating System for fixation distal femoral non-implant related and periprosthetic fractures

The objective of this study was to report on the safety, efficacy and clinical outcomes of the Polyax Locked Plating System (Biomet, Warsaw, IN, USA) in the management of acute (non-implant related and periprosthetic) distal femoral fractures. We retrospectively reviewed 71 patients with 73 distal femoral fractures. Thirty-three of the included fractures occurred around previously placed implants. The average patients' age was 67 years (range 18-98). There were 7 early postoperative complications (9.5%) including one deep surgical site infection, 2 pulmonary embolisms and 4 urinary or respiratory infections. At final follow-up (mean 12, range 9-55 months) all fractures progressed to clinical and radiological union. However, major revision surgery for healing problems was required in 5 cases (6.8%) and minor in 3 cases (4.1%). The average time to healing was 6 (range 3-23) months. Angulation less than 5 degrees in any plane was observed in 66 cases (89.7%), within 5-10 degrees in 5 cases (7.3%) and within 10-15 degrees in 2 cases (2.9%). The mean pre-injury and final follow-up values of Glasgow Outcome Scale were 1.5(1-3) and 1.7(1-3) respectively. Overall 61 patients (83.53%) retained their pre-injury activity status. The Polyax Locked Plating System offers a safe and efficient fixation in distal femoral fractures.

Results of treatment of distal extra: articular femur fractures with locking plates using minimally invasive approach--experience with 25 consecutive geriatric patients

PURPOSE

Fractures involving the femur in older adults are reasonably common. The aim of this study was to evaluate the results of MIPO technique using locking plates in geriatric patients for distal extra-articular femur fractures.

METHODS

About 25 consecutive patients with distal extra-articular femur fractures aged 60 years and above were treated using locking plates and minimally invasive technique. Patients were studied prospectively over a period of 3 years. Parameters studied included patient demographics, fracture type, time taken for the surgery, time to union and any complications.

RESULTS

Mean age of patients was 66.5 years. Nineteen (76%) patients were females. Most of fractures in our study were type 33A2 fractures (64%). Average time to full weight bearing was 14.32 weeks, and fractures united at an average of 16.88 weeks. There were two (8%) patients with superficial infection, two (8%) with implant tenderness. One (4%) patient developed knee stiffness. Five (20%) patients had extension lag of average 5°. One (4%) patient sustained a peri-implant fracture at 2 months. None of the patients developed non-union or delayed union. According to criteria laid by Schatzker's and Lambert, excellent results were achieved in 22 (88%) patients.

CONCLUSIONS

Outcome of minimally invasive fixation of distal extra-articular femur fractures with locking plates in patients of age 60 years and above seems to be good with high union rate despite high prevalence of osteoporosis and comminution.

Combination of modified free vascularized fibular grafting and reverse Less Invasive Stabilization System (LISS) for the management of femoral neck nonunion in patients thirty years of age or younger

Femoral neck nonunion (FNN) is a potential complication in patients with displaced femoral neck fractures, occurring in 33%. This may lead to early hip dysfunction or arthroplasty. Combination of modified free vascularized fibular grafting (FVFG) and a reverse LISS may provide a reasonable means to salvage a painless, functional and native hip. Between August 2010 and August 2012, sixteen patients with femoral neck nonunion were treated with a combined procedure involving modified free vascularized fibular grafting and a reverse LISS. The average age of them is 20.3 years (range 12.0-28.0 years). After removing old implants, the nonunion site was debrided, reduced and fixed with a LISS. The fibular grafts were compacted into a trough in the femoral neck. The Harris Hip score system was used to assess hip function and anteroposterior and frog-lateral hip roentgenograms were used to evaluate bone healing. All femoral neck nonunion healed without severe complications. The mean follow-up time was 32.9 months (range 23.0-47.0 months) and the average union time was 7.6 months (range 5.0-10.0 months). All coxa vara deformities and retroversions of the femoral head were corrected. The Harris hip scores (HHS) were improved 36.6 points on average (59.6 points preoperatively to 96.2 points postoperatively). No incidences of osteonecrosis of the femoral head were observed. The combined modified FVFG and reverse LISS plating is a suitable procedure for the management of femoral neck nonunion in patients younger than 30 years, especially for those patients with a revision history.

Radiological assessment of the safe zone for medial minimally invasive plate osteosynthesis in the distal femur with computed tomography angiography

INTRODUCTION

Surgical treatment options for distal femur fractures include intramedullary nailing or plating using a lateral or lateral parapatellar approach. However, medial plating is required for additional stability in some fractures such as severely comminuted fractures and periprosthetic fractures, and in those for which use of a lateral plate or nail is not appropriate. This study aimed to explore the safe zone for medial minimally invasive plate osteosynthesis of the distal femur with computed tomography angiography.

MATERIAL AND METHODS

In a series of 30 patients, the region of interest between the lesser trochanter (LT) to the adductor tubercle (AT) was divided into six levels (I to VI), and the distance from the femur to the femoral artery (FA) was measured. At each level, the medial half of the femur was divided into eight sections that were assigned ‘A to H’ from anteromedial to posteromedial, and the position of the FA and the deep femoral artery (DFA) was recorded.

RESULTS

The average length from the LT to AT was 295.0 mm. The average distance to FA was 38.0 mm, 29.9 mm, 26.9 mm, 27.0 mm, 21.8 mm, and 12.2 mm from level I to VI, respectively. The FA was positioned posteromedially below level IV and positioned at C–H below level II, which was out of the anterior aspect of the femur. The DFA was in the same location as the FA between levels II and III.

CONCLUSION

The anteromedial aspect of the distal half of the femur is the safe zone, and a long plate can be positioned safely in this zone at the anterior aspect up to the level of 8 cm below the LT.

Biomechanical design of less invasive stabilization system femoral plates: computational evaluation of the fracture environment

Less Invasive Stabilization System femoral plates are currently accepted as a suitable fixation technique for supra-intercondylar femoral fractures. However, general agreement does not exist regarding the optimum design of this fixator type. Therefore, the aim of this article is to reduce the intrinsic Less Invasive Stabilization System complications by clarifying, from a biomechanical point of view, how the number of screws, the screw connection type (unicortical or bicortical), or the structured position of the screws can influence the outcome of the fracture site. These studies include a specific finite element analysis that determines how several biomechanical variables, such as the movement at the fracture site, are influenced by the preconditions of bone healing. The results of this study show that the screw type affects the mechanical stabilization of the femur to a greater extent than the material type of the Less Invasive Stabilization System femoral plates. The most significant differences among all the analyzed configurations are observed in the shear interfragmentary strain between screw types. Values are approximately 50% higher with unicortical screws than with bicortical ones.

Biomechanical assessment of composite versus metallic intramedullary nailing system in femoral shaft fractures: A finite element study

BACKGROUND

Intramedullary nails are the primary choice for treating long bone fractures. However, complications following nail surgery including non-union, delayed union, and fracture of the bone or the implant still exist. Reducing nail stiffness while still maintaining sufficient stability seems to be the ideal solution to overcome the abovementioned complications.

METHODS

In this study, a new hybrid concept for nails made of carbon fibers/flax/epoxy was developed in order to reduce stress shielding. The mechanical performance of this new implant in terms of fracture stability and load sharing was assessed using a comprehensive non-linear FE model. This model considers several mechanical factors in nine fracture configurations at immediately post-operative, and in the healed bone stages.

RESULTS

Post-operative results showed that the hybrid composite nail increases the average normal force at the fracture site by 319.23N (P<0.05), and the mean stress in the vicinity of fracture by 2.11MPa (P<0.05) at 45% gait cycle, while only 0.33mm and 0.39mm (P<0.05) increases in the fracture opening and the fragments' shear movement were observed. The healed bone results revealed that implantation of the titanium nail caused 20.2% reduction in bone stiffness, while the composite nail lowered the stiffness by 11.8% as compared to an intact femur.

INTERPRETATION

Our results suggest that the composite nail can provide a preferred mechanical environment for healing, particularly in transverse shaft fractures. This may help bioengineers better understand the biomechanics of fracture healing, and aid in the design of effective implants.

Treatment of distal femur fractures in a regional Australian hospital

AIM: To review our outcomes and compare the results of the Less Invasive Stabilization System (LISS) to other implants for distal femur fracture management at a regional Australian hospital.

METHODS: The LISS is a novel implant for the management of distal femur fractures. It is, however, technically demanding and treatment results have not yet been assessed outside tertiary centres. Twenty-seven patients with 28 distal femur fractures who had been managed surgically at the Mackay Base Hospital from January 2004 to December 2010 were retrospectively enrolled and assessed clinically and radiologically. Outcomes were union, pain, Lysholm score, knee range of motion, and complication rates.

RESULTS: Twenty fractures were managed with the LISS and eight fractures were managed with alternative implants. Analysis of the surgical techniques revealed that 11 fractures managed with the LISS were performed according to the recommended principles (LISS-R) and 9 were not (LISS-N). Union occurred in 67.9% of fractures overall: 9/11 (82%) in the LISS-R group vs 5/9 (56%) in the LISS-N group and 5/8 (62.5%) in the alternative implant group. There was no statistically significant difference between pain, Lysholm score, and complication rates between the groups. However, there was a trend towards the LISS-R group having superior outcomes which were clinically significant. There was a statistically significant greater range of median knee flexion in the LISS-R group with compared to the LISS-N group (P = 0.0143) and compared with the alternative implant group (P = 0.0454).

CONCLUSION: The trends towards the benefits of the LISS procedure when correctly applied would suggest that not only should the LISS procedure be performed for distal femur fractures, but the correct principle of insertion is important in improving the patient’s outcome.

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

INTRODUCTION

Reported initial success rates after lateral locked plating (LLP) of distal femur fractures have led to more concerning outcomes with reported nonunion rates now ranging from 0 to 21%. Reported factors associated with nonunion include comorbidities such as obesity, age and diabetes. In this study, our goal was to identify patient comorbidities, injury and construct characteristics that are independent predictors of nonunion risk in LLP of distal femur fractures; and to develop a predictive algorithm of nonunion risk, irrespective of institutional criteria for clinical intervention variability.

PATIENTS AND METHODS

A retrospective review of 283 distal femoral fractures in 278 consecutive patients treated with LLP at three Level1 academic trauma centers. Nonunion was liberally defined as need for secondary procedure to manage poor healing based on unrestricted surgeon criteria. Patient demographics (age, gender), comorbidities (obesity, smoking, diabetes, chronic steroid use, dialysis), injury characteristics (AO type, periprosthetic fracture, open fracture, infection), and management factors (institution, reason for intervention, time to intervention, plate length, screw density, and plate material) were obtained for all participants. Multivariable analysis was performed using logistic regression to control for confounding in order to identify independent risk factors for nonunion.

RESULTS

28 of the 283 fractures were treated for nonunion, 13 were referred to us from other institutions. Obesity (BMI>30), open fracture, occurrence of infection, and use of stainless steel plate were significant independent risk factors (P<0.01). A predictive algorithm demonstrates that when none of these variables are present (titanium instead of stainless steel) the risk of nonunion requiring intervention is 4%, but increases to 96% with all factors present. When a stainless plate is used, obesity alone carries a risk of 44% while infection alone a risk of 66%. While Chi-square testing suggested no institutional differences in nonunion rates, the time to intervention for nonunion varied inversely with nonunion rates between institutions, indicating varying trends in management approach.

DISCUSSION

Obesity, open fracture, occurrence of infection, and the use of stainless steel are prognostic risk factors of nonunion in distal femoral fractures treated with LLP independent of differing trends in how surgeons intervene in the management of nonunion.

Current options to surgical treatment in osteoporotic fractures

Treatment of osteoporotic fractures leads to significant challenges for the surgeon, including poor implant fixation related to low bone quality and compromised capacity of fracture healing. This article reviews the osteosynthesis and arthroplasty results in the surgical treatment of proximal femur, proximal humerus and wrist fractures to define the current options to decrease failure in fragility fracture management.

Currents of plate osteosynthesis in osteoporotic bone

Osteoporotic fractures are becoming more prevalent with ageing of populations worldwide. Inadequate fixation or prolonged immobilization after non-surgical care leads to serious life-threatening events, poor functional results and lifelong disability. Thus, a stable internal fixation and rapid initiation of rehabilitation are required for faster return of function. Conventional internal fixation attempts to achieve the exact anatomy, often with extended soft-tissue stripping and compression of the periosteum, causing disturbance of the metaphyseal and comminuted fracture's bone blood supply. This technique relies on frictional forces between bone and plate. Osteoporotic bone might not be able to generate enough torque with the screw to securely fix the plate to bone. Thus, this surgical management have resulted in increased incidence of poor results in elderly, osteoporotic patients. The newly developed locked internal fixators, locking compression plates and less invasive stabilization system, consist of plate and screw systems where the screws are locked in the plate, minimizing the compressive forces exerted between plate and bone. Thus, the plate does not need to compress the bone nor requires precise anatomical contouring of a plate disturbing the periosteal blood supply. These fixators allowed the development of the minimal invasive percutaneous osteosynthesis. Nowadays, locking plates are the fixation method of choice for osteoporotic, diaphyseal or metaphyseal, severely comminuted fractures.

Immediate weight bearing of comminuted supracondylar femur fractures using locked plate fixation

Comminuted supracondylar femur fractures (AO-OTA 33A3) are commonly treated with locked plates. Weight bearing is generally restricted for 6 to 12 weeks until radiologic evidence exists of sufficient callous to support weight bearing. Recent clinical studies have reported high nonunion rates with distal femur locked plates. In an attempt to induce beneficial motion across the fracture site, some studies have recommended earlier weight bearing. The purpose of the current study was to determine the biomechanical feasibility of an immediate weight-bearing rehabilitation protocol to encourage healing of distal femur fractures treated with lateral locked plate fixation.Sixteen fresh-frozen cadaveric femora were used for this study. A 2.5-cm supracondylar gap osteotomy was made. Ten-hole, 4.5-mm distal femur locking plates were used with a standardized screw configuration that maximized the working length. The specimens were placed in a servohydraulic testing machine and axially loaded (unidirectional) at 1 Hz for up to 200,000 cycles. Failure was defined as 1 cm of deformation of the construct. The staircase method was used to determine the fatigue limit of the construct. The fatigue limit was calculated to be 1329±106 N. No specimen failed through the non-locking diaphyseal screws. Plastic deformation, when present, occurred at the metaphyseal flare of the plate. The fatigue limit of the locked plate constructs equaled 1.9 times body weight for an average 70-kg patient over a simulated 10-week postoperative course. Given that distal femoral loads during gait have been estimated to be more than 2 times body weight, the data from this study do not support immediate full weight bearing.

Highly unstable complex C3-type distal femur fracture: can double plating via a modified Olerud extensile approach be a standby solution?

Background

Multiplanar complex C3-type unstable distal femoral fractures present many challenges in terms of approach and fixation. This prospective study investigates a possible solution to these problems through double plating with autogenous bone grafting via a modified Olerud extensile approach.

Materials and methods

Twelve patients with closed C3-type injuries were included; eight of them were male, and their mean age was 33.5 years (range 22–44 years). Mechanism of injury was road traffic accident (RTA) in nine patients and fall from height in the other three cases. Eight cases were operated during the first week and four cases during the second week after injury. Mean follow-up was 13.7 months (range 11–18 months).

Results

Mean radiological healing time was 18.3 weeks (range 12-28 weeks), and all cases had good radiological healing without recorded nonunion or malunion. Clinically, two cases (16.7 %) had excellent results, five cases (41.7 %) had good results, three cases (25 %) had fair results, and two cases (16.7 %) had poor results. No cases developed skin necrosis, deep infection, bone collapse, or implant failure. However, two cases (16.7 %) had limited knee flexion to 90° and required subsequent quadricepsplasty.

Conclusions

Use of this modified highly invasive approach facilitated anatomical reconstruction of C3-type complex distal femoral fractures with lower expected complication rate and acceptable clinical outcome, especially offering good reconstruction of the suprapatellar pouch area. It can be considered as a standby solution for managing these difficult injuries.

Comparison of the 95-degree angled blade plate and the locking condylar plate for the treatment of distal femoral fractures

OBJECTIVES

In the distal femur, locked plating is efficacious when coronal fractures preclude the use of a conventional fixed-angle device. However, minimal comparative data exist for supracondylar fracture patterns, which could be treated with other devices. The purpose of this study was to compare the 95-degree angled blade plate (ABP) versus the Locking Condylar Plate (LCP) by assessing complications and secondary procedures in fractures amenable to treatment with either implant.

DESIGN

Retrospective review.

SETTING

Level 1 trauma center.

PATIENTS/PARTICIPANTS

Seventy patients with 71 distal femoral fractures (OTA 33-A, 33-C1, 33-C2) amenable to either ABP or LCP with a mean age of 59.5 years (range, 20-92 years) were included. Seventeen fractures (24%) occurred adjacent to a previous knee arthroplasty (10 ABP and 7 LCP). The 2 groups were similar with respect to age, fracture pattern, and the presence of open fracture. Most injuries were the result of high-energy trauma, and 21% were open fractures.

INTERVENTION

Thirty-two fractures (45%) were treated with an ABP, and 39 (55%) were treated with the LCP.

MAIN OUTCOME MEASURES

Complications, including infection, nonunion, and malunion, and secondary operations were determined.

RESULTS

After a mean of 26-month follow-up, 4 patients (6.0%) were treated for infections. Malunions occurred in 11% of LCP patients and in 1 ABP patient (3.4%, P = 0.14). All patients with malunions were older than 55 years. Seven patients (11%) were treated for nonunions. Six of the nonunions occurred after LCP (16% vs. 3.4%, P = 0.11) Complications were more frequent in LCP patients (35%) versus ABP patients (10%, P = 0.001). Complications were not related to fracture pattern, periprosthetic fracture, or open fracture. Mean age of patients with complications was 64 years (vs. 53 years, P = 0.01), and they were more likely to have lower energy mechanisms (P = 0.017). Overall, 18 patients (27%) underwent secondary procedures, including treatment of infection, nonunion, malunion, or prominent implant removal. Secondary procedures were more common after LCP (43%) versus ABP (6.9%, P = 0.0008) patients. Painful prominent implants were removed from 7 LCP patients (18%) and no ABP patients (P = 0.01).

CONCLUSIONS

Distal femur fractures are often associated with prolonged healing and rehabilitation times, which increase substantially when complications occur. Internal fixation of these fractures may be performed successfully with ABP or LCP. In our review of fractures that could be treated with either implant, patients treated with locking plates had more complications and nonunions, requiring more secondary procedures to treat complications and to remove prominent implants. Furthermore, locking plates are substantially more expensive than conventional fixed-angle devices. Future investigation is needed in the form of a large randomized prospective study to clearly define clinical differences, functional outcomes, and costs of care.

LEVEL OF EVIDENCE

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

Less invasive stabilization system (LISS) versus proximal femoral nail anti-rotation (PFNA) in treating proximal femoral fractures: a prospective randomized study

OBJECTIVE

To evaluate the outcome and efficacy of LISS (Less Invasive Stabilization System; Synthes USA, Paoli, PA) for the treatment of proximal femoral fractures to find another appropriate minimally invasive surgery for these fractures in which intramedullary nailing may be difficult.

DESIGN

A consecutive prospective randomized clinical study.

SETTING

University teaching hospital.

PATIENTS

Between May 2006 and March 2008, 64 consecutive patients who had a proximal femoral fracture were randomized to be treated with fixation with either LISS or PFNA (Proximal Femoral Nail Anti-rotation; Synthes USA).

INTERVENTION

LISS or PFNA fixation of proximal femoral fractures.

MAIN OUTCOME MEASUREMENTS

Intraoperative time, intraoperative blood loss, length of hospitalization, hip function (Harris score), general complications, fracture complications.

RESULTS

Fifty-nine patients were evaluated with a mean follow-up time of 26.8 months (range, 21-36 months). No statistical differences in general complications, intraoperative blood loss, length of hospitalization, or hip function could be found between the two groups. The average operative time was longer in the LISS group (98.25 minutes) compared with the PFNA group (65.36 minutes) (P < 0.05). One PFNA case had intrapelvic penetration of the helical blade; two LISS cases had breakage of the screws.

CONCLUSION

There were no major differences in outcome or complications between the treatment groups. LISS can be used effectively in treating proximal femoral fractures, especially for complex fractures patterns in which intramedullary nailing may be difficult.

LEVEL OF EVIDENCE

Therapeutic Level II. See page 128 for a complete description of levels of evidence.

2010 mid-America Orthopaedic Association Physician in Training Award: healing complications are common after locked plating for distal femur fractures

BACKGROUND

Several mechanical studies suggest locking plate constructs may inhibit callus necessary for healing of distal femur fractures. However, the rate of nonunion and factors associated with nonunion are not well established.

QUESTIONS/PURPOSES

We (1) determined the healing rate of distal femur fractures treated with locking plates, (2) assessed the effect of patient injury and treatment variables on fracture healing, and (3) compared callus formation in fractures that healed with those that did not heal.

PATIENTS AND METHODS

We retrospectively reviewed 82 patients treated with 86 distal femur fractures using lateral locking plates. We reviewed all charts and radiographs to determine patient and treatment variables and then determined the effects of these variables on healing. We quantitatively measured callus at 6, 12, and 24 weeks. The minimum time for telephone interviews and SF-36v2(TM) scores was 1 year (mean, 4.2 years; range, 1-7.2 years).

RESULTS

Fourteen fractures (20%) failed to unite. Demographics and comorbidities were similar in patients who achieved healing compared with those who had nonunions. There were more empty holes in the plate adjacent to fractures that healed; comminuted fractures failed to heal more frequently than less comminuted fractures. Less callus formed in fractures with nonunions and in patients treated with stainless steel plates compared with titanium plates. Complications occurred in 28 of 70 fractures (40%), 19 of which had additional surgery.

CONCLUSIONS

We found a high rate of nonunion in distal femur fractures treated with locking plates. Nonunion presented late without hardware failure and with limited callus formation suggesting callus inhibition rather than hardware failure is the primary problem. Mechanical factors may play a role in the high rate of nonunion.

Locking plates for distal femur fractures: is there a problem with fracture healing?

OBJECTIVES

Fractures of the distal femur are severe injuries that present many clinical challenges. Nonunion, delayed union, implant failure, and the need for secondary procedures can reflect complications of healing. This article reviews the literature on distal femur fractures treated with locking plates to determine the reported rate of healing difficulties.

DATA SOURCES

The PubMed database and the Orthopaedic Trauma Association and American Academy of Orthopedic Surgeons abstract archives were searched for studies including the key words distal femur fracture, supracondylar femur fracture, or locking plate from the year 2000 to the present.

STUDY SELECTION

Reports were included when distal femur fractures were treated with locking plates and when the number of healed fractures was identified in the study. The reported healing rates and the rate of healing complications were determined from the studies. The time to implant failure was recorded. Those articles that included periprosthetic fractures were separated from those only including acute distal femur fractures.

DATA SYNTHESIS

Fifteen full-length publications and three abstracts were included. The rate of complications related to healing ranged from 0% to 32% in these studies. Implant failures occurred late with 75% of the failures occurring after 3 months and 50% occurring after 6 months.

CONCLUSIONS

Complications of healing including nonunion, delayed union, and implant failure are not infrequent and represent ongoing problems with distal femur fracture treatment. Further clinical research combined with innovation in surgical techniques and implant design will be necessary to improve the results of the last decade.

Locked plating of distal femur fractures leads to inconsistent and asymmetric callus formation

OBJECTIVES

Locked plating constructs may be too stiff to reliably promote secondary bone healing. This study used a novel imaging technique to quantify periosteal callus formation of distal femur fractures stabilized with locking plates. It investigated the effects of cortex-to-plate distance, bridging span, and implant material on periosteal callus formation.

DESIGN

Retrospective cohort study.

SETTING

One Level I and one Level II trauma center.

PATIENTS

Sixty-four consecutive patients with distal femur fractures (AO types 32A, 33A-C) stabilized with periarticular locking plates.

INTERVENTION

Osteosynthesis using indirect reduction and bridge plating with periarticular locking plates.

MAIN OUTCOME MEASUREMENT

Periosteal callus size on lateral and anteroposterior radiographs.

RESULTS

Callus size varied from 0 to 650 mm2. Deficient callus (20 mm2 or less) formed in 52%, 47%, and 37% of fractures at 6, 12, and 24 weeks postsurgery, respectively. Callus formation was asymmetric, whereby the medial cortex had on average 64% more callus (P=0.001) than the anterior or posterior cortices. A longer bridge span correlated minimally with an increased callus size at Week 6 (P=0.02), but no correlation was found at Weeks 12 and 24 postsurgery. Compared with stainless steel plates, titanium plates had 76%, 71%, and 56% more callus at Week 6 (P=0.04), Week 12 (P=0.03), and Week 24 (P=0.09), respectively.

CONCLUSIONS

Stabilization of distal femur fractures with periarticular locking plates can cause inconsistent and asymmetric formation of periosteal callus. A larger bridge span only minimally improves callus formation. The more flexible titanium plates enhanced callus formation compared with stainless steel plates.

Treatment of distal femoral fracture by minimally invasive percutaneous plate osteosynthesis: comparison between the dynamic condylar screw and the less invasive stabilization system

BACKGROUND

Treatment of distal femoral fractures by percutaneous plating without direct manipulation of the fracture fragments leads to good clinical outcome. Percutaneous plating has traditionally involved using a dynamic condylar screw (DCS) and the less invasive stabilization system (LISS) was reported. The biomechanical study showed that the LISS had the enhanced ability to withstand higher loads. However, there were no clinical comparison study of distal femoral fractures treated with DCS and LISS. The aim of this study was to outline any differences in clinical and radiological results between the DCS and the LISS for treating distal femoral fractures.

METHODS

Forty-five supracondylar or intercondylar femoral fractures were treated by minimally invasive percutaneous plating with the DCS or the LISS without bone graft. There were 26 patients with 26 fractures in the DCS group and 19 patients with 19 fractures in the LISS group. The data of the clinical and radiographic outcomes were compared between the two different fixation devices.

RESULTS

Complete union was achieved in 41 of the 45 patients (91.1%). The success rate was 96.2% in the DCS group and 94.7% in the LISS group (p = 0.672). The mean fusion time was 19.18 weeks in the DCS group and 19.38 weeks in the LISS group (p = 0.835). The average range of motion of the knee joint was 111.65 degrees in the DCS group and 116.26 degrees in the LISS group (p = 0.334). Early implant failure only occurred in the DCS group (11.5%, p = 0.252, odds ratio = 1.826 [95% CI: 1.387-2.404]). The total complication rate was 15.4% in the DCS group and 15.8% in the LISS group (p = 0.641). The mean loss of coronal fracture fragment angle was -0.77 degrees in the DCS group and -0.19 degrees in the LISS group (p = 0.125).

CONCLUSION

Minimally invasive percutaneous plating with the DCS or the LISS provides good outcome with few complications in the treatment of distal femoral fractures. Both systems minimize soft tissue trauma. LISS seems to have lower risk of early implant loosening than the DCS.

The role of LISS (less invasive stabilisation system) in the treatment of peri-knee fractures

The purpose of present study was to evaluate the role of LISS after a large series of patients in whom a fracture around the knee had been treated with this uniform technique. Between April 2004 and September 2006, 210 patients with a total of 216 fractures around the knee were treated with LISS, all at the Affiliated Hospital to Nantong University. Patients were followed for a mean of 27 months (range 12-42 months). 26 patients were excluded from the study. The remaining 184 patients with a total of 189 fractures of either distal femur (85 cases) or proximal tibia (104 cases) were available for analysis. The mean age of these patients was 49 years (range 18-82 years). Immediate postoperative X-rays showed the alignment of bone and joint was satisfactorily maintained with LISS in all cases and an ideal implant position in 176 cases (93%). All cases healed the fracture without non-union. The mean time to union was 15 weeks (range 12-27 weeks) for the femoral and 16 weeks (range 12-27 weeks) for the tibia fractures. Functional assessment was performed using HSS (hospital for special surgery) score. At the time of the latest follow-up, 158 patients (86%) had an excellent or good outcome. Overall, 3 patients were subject to a salvage operative procedure due to implant failure. Three cases underwent secondary bone graft for open fractures. Superficial and deep infection was found each in one patient and both were treated successfully. Hardware prominence irritation was found in 2 patients. LISS was removed in 27 patients after bone healing, and this procedure was neither less invasive nor easy as imagined. The results indicate the LISS system is perfect but by no means unique in the treatment of the fractures around the knee. The fixation is adequate enough to maintain alignment and obtain union with a low incidence of complications even in patients with osteoporotic bone. We firmly believe favourable results can be achieved when this device is combined with correct indications as well as skillful techniques.

The clinical and radiological outcomes of the LISS plate for distal femoral fractures: a systematic review

PURPOSE

The purpose of this systematic review was to assess the literature evaluating the clinical and radiological outcomes following less invasive surgical stabilisation system (LISS) fixation of distal femoral fractures (AO 32/33).

METHODS

A review of EMBASE, Medline, CINAHL and AMED from their inception to November 2008, sources of grey literature and a pertinent hand search of specialist orthopaedic journals was undertaken.

RESULTS

Twenty-one studies assessing 663 patients with 694 fractures were reviewed. The findings suggest that the LISS system may be an appropriate fixation method for the management of distal femoral fractures. However, there remains a high incidence of loss of reduction (n=134; 19%), delayed or non-union (n=40; 6%) and implant failure (n=38; 5%). On analysis, such complications were largely confined to articles published before 2005, therefore during the infancy of the widespread clinical application of this trauma system. On critical appraisal, the evidence-base remains limited by recruiting small, under-powered sample sizes and poorly accounting for confounding variables such as osteoporosis, diabetes, multi-trauma and fracture classification.

CONCLUSION

Further study is required to assess the outcomes of LISS fixation in specific patient populations, and to compare the outcome of this fixation method to condylar plates and intrameduallary devices, to determine the optimal management strategy for this complex patient group.

Locking plates for extremity fractures

Thirty-three peer-reviewed studies met the inclusion criteria for the Overview. Criteria were framed by three key questions regarding indications for the use of locking plates, their effectiveness in comparison with traditional nonlocking plates, and their cost-effectiveness. The studies were divided into seven applications: distal radius, proximal humerus, distal femur, periprosthetic femur, tibial plateau (AO/OTA type C), proximal tibia (AO/OTA type A or C), and distal tibia. Patient enrollment criteria were recorded to determine indications for use of locking plates, but the published studies do not consistently report the same enrollment criteria. Regarding effectiveness, there were no statistically significant differences between locking plates and nonlocking plates for patient-oriented outcomes, adverse events, or complications. The literature search did not identify any peer-reviewed studies that address the cost-effectiveness or cost-utility of locking plates.

Early rehabilitation following less invasive surgical stabilisation plate fixation for distal femoral fractures

OBJECTIVE

The less invasive surgical stabilisation (LISS) plate fixation method is an orthopaedic procedure for the fixation of distal femoral fractures. Early physiotherapy treatments of motion and mobilisation have been advocated following this procedure. This article critically appraises the evidence base assessing the early rehabilitation of patients following LISS fixation for distal femoral fractures.

DATA SOURCES

A review of EMBASE, Medline, CINAHL and AMED, and a hand search were undertaken.

REVIEW METHODS

Two independent reviewers identified all eligible articles. Two reviewers extracted the data, which were verified by a third reviewer. All included articles were critically appraised by two independent reviewers using the Critical Appraisal Skills Programme tool.

RESULTS

Seventeen case series assessing 508 patients with 535 fractures were reviewed. No clinical trials comparing physiotherapy programmes were identified. The review identified that following LISS fixation for distal femoral fractures, patients begin range-of-motion exercises immediately and are initially required to restrict weight-bearing following surgery. It remains unclear whether casts, braces or immobilisation aids are applied during the initial postoperative period.

CONCLUSION

The efficacy of different physiotherapy protocols following LISS fixation for distal femoral fractures remains unclear. Further well-designed randomised controlled trials are required to compare different postoperative physiotherapy rehabilitation programmes for patients following LISS fixation of distal femoral fractures in order to determine the optimal postoperative management for this complex patient group.

The condylar plate for treatment of distal femoral fractures: a long-term follow-up study

The aim of this retrospective study was to present the long-term functional and radiological outcomes of indirect reduction techniques and fixation with a condylar plate for treatment of distal femoral supracondylar or intracondylar femoral fractures. The series included 24 men and 17 women, mean age 51 years, between March 1994 and April 1999. All fractures were AO type 33, and eight were open fractures. Primary iliac bone graft was used in five cases. In one case of severe osteoporosis, screw fixation was augmented with cement. There were three delayed unions, one non-union and two infections; four participants required reoperation with bone grafts. Two (5%) participants developed a second varus deformity and three a second valgus deformity; correction osteotomy with bone grafts was necessary in these cases. After a mean follow-up of 9.5 years, the mean Neer score was 82 points and indicated that function was excellent in 16, satisfactory in 9, unsatisfactory in 4 and poor in 2 cases. The mean Neer score in cases of isolated fracture was 89 points and in cases with additional injuries was 72 points. Thus the long-term results of indirect reduction techniques of distal femoral fractures treated with the condylar plate were good to excellent in 82% of cases.

Fixation of distal femoral fractures with the Less Invasive Stabilization System: a minimally invasive treatment with locked fixed-angle screws

BACKGROUND

The Less Invasive Stabilization System (LISS) is an internal fixator, which combines closed reduction of the diaphysis or metaphysis of distal femur fractures with locked unicortical screw fixation.

METHODS

In a retrospective consecutive study, 50 patients with Association for the Study of the Problems of Internal Fixation/Orthopaedic Trauma Association (AO/OTA) type 33-A1 to 33-C3 fractures were treated with the LISS between January 1999 and December 2003. Final results were assessed using the functional score of Neer after a median follow-up of 29 months (15-48 months).

RESULTS

Fifteen male and 16 female patients were followed up. The mean age was 49 years (17-90 years). Deep wound infection was seen in one patient (3%) and malpositioning with cutting-out of the proximal screws was in two patients (6%). All other fractures healed uneventfully without bone graft requirements after a mean of 12 weeks (7-20 weeks). A revised osteosynthesis was performed for correction of a valgus deformity of 20 degrees after 4 months. There was no difference in leg length exceeding 2 cm. One patient had a valgus deformity of 10 degrees combined with a rotational deformity of 10 degrees. Range of motion of the knee joint was >120 degrees in 15 patients (48%); 12 (39%) had a range of motion between 90 degrees and 120 degrees and 4 (13%) between 70 degrees and 90 degrees. The function according to the Neer score was excellent in 15 (48%), good in 10 patients (32%), and fair in 6 patients (20%). The mean Neer score was 80 (60-100).

CONCLUSIONS

The LISS promotes early mobilization and rapid rates of bony and clinical healing without bone grafting with low rates of infection.

Long-term functional outcomes after intra-articular distal femur fractures: ORIF versus retrograde intramedullary nailing

This retrospective study evaluated the long-term clinical, functional, and radiographic outcomes of traditional open reduction internal fixation (ORIF) versus limited open reduction with retrograde intramedullary nailing for supracondylar-intercondylar distal femur fractures (Arbeitsgemeinschaft für Osteosynthesefragen [AO] 33-C type). Twenty-three fractures were followed in 22 patients for a mean follow-up of 80 months. The rate of subsequent bone-grafting procedures (67% vs 9%) and malunion (42% vs 0%) were significantly higher in ORIF compared to the less invasive retrograde intramedullary nailing treatment. A nonsignificant trend was noted for increased infection (25% vs 0%) and nonunion (33% vs 9%) in the ORIF group. The physical function component of the SF-36 was approximately 2 standard deviations below the US population mean, and 50% of patients demonstrated radiographic changes of posttraumatic arthritis. No patient has had a subsequent total knee arthroplasty.

Treatment of acute distal femur fractures

An emphasis on indirect reduction techniques to restore limb alignment has improved the rate of fracture healing and decreased infection rates, fixation failure, and the need for bone grafting.