‘Modern’ distal femoral locking plates allow safe, early weight-bearing with a high rate of union and low rate of failure

Weightbearing versus non-weight bearing in geriatric distal femoral fractures: a systematic review and meta-analysis

BACKGROUND

Demographics of patients who sustain geriatric distal femoral fractures (DFF) match those of patients with neck-of-femur fractures but have limited evidence with which to support post-operative weightbearing protocols.

PURPOSE

This systematic review sought to identify any difference in outcomes for elderly patients with DFF who were allowed early versus delayed weightbearing postoperatively.

METHODS

DATA SOURCES: PubMed, Medline, Embase and The Cochrane Library, reference lists of retrieved articles.

STUDY SELECTION

English language papers published between January 2010 and February 2023 with AO-OTA type 33A, B and C femoral fractures as well as Lewis and Rorabeck Type I and II periprosthetic DFF surgically treated with either a lateral locking plate or retrograde intramedullary nail and an average patient age of ≥ 60 years.

DATA EXTRACTION

Studies were assessed for inclusion by two authors and quality was assessed using the MINORS tool.

DATA SYNTHESIS

Sixteen studies were included, Meta-analysis of non-union, malunion, infection, delayed union and implant complications was performed using Microsoft Excel and the MetaXL extension. The data on return to mobility were presented in narrative form. The analyses demonstrated no difference between the early and delayed weightbearing groups.

CONCLUSIONS

There are no significant differences in complication rates between early versus delayed weightbearing after surgery for DFF in an elderly population. The study results are limited by high heterogeneity and low-quality studies. High quality, prospective studies are needed to determine the ideal postoperative weightbearing protocol.

LEVEL OF EVIDENCE

Level III, Systematic Review and Meta-analysis of Level III studies. International Prospective Register of Systematic Reviews registration-Prospero CRD42022371460.

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

Background

Periprosthetic fracture is a rare complication of arthroplasty but can have devastating consequences for the patient and presents a complex surgical challenge. Locking compression plate and retrograde intramedullary nail are both widely accepted surgical fixation techniques for distal femoral periprosthetic fractures around a total knee arthroplasty. Although there is still a need for further high-quality research into both techniques, there is even less literature concerning the use of distal femoral replacement to treat distal femoral periprosthetic fractures. Interest has been piqued in distal femoral replacements for the treatment of distal femoral periprosthetic fractures due to the theoretical advantages of immediate post-operative weight-bearing and lack of dependence on fracture union, but there are still understandably reservations about performing such an extensive and invasive procedure when an accepted alternative is available. This meta-analysis aims to evaluate the current literature to compare the complication rates and return to pre-operative ambulatory status of distal femoral replacement and locking compression plate.

Method

A literature search was performed to identify articles related to the management of distal femoral periprosthetic fractures around a total knee arthroplasty in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Methodological quality was assessed using the methodological index for non-randomized studies (MINORS) criteria. Articles were reviewed, and data extracted for analysis.

Results

Five articles met the inclusion criteria, reporting on 345 periprosthetic fractures. The overall rates of complications for distal femoral replacement and locking compression plate were: re-operation (6.1% vs 12.1%), infection (3.0% vs 5.3%), mortality (19.7% vs 19.3%), and return to pre-operative ambulatory status (60.9% vs 71.8%) (respectively).

Conclusion

This meta-analysis shows no statistically significant difference in the rates of re-operation, infection, mortality or return to pre-operative ambulatory status when comparing distal femoral replacement to locking compression plate.

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%.

Retrograde Intramedullary Nailing Versus Locked Plating for Extreme Distal Periprosthetic Femur Fractures: A Multicenter Retrospective Cohort Study

OBJECTIVES

To compare clinical and radiographic outcomes after retrograde intramedullary nailing (rIMN) versus locked plating (LP) of "extreme distal" periprosthetic femur fractures, defined as those that contact or extend distal to the anterior flange.

METHODS

DESIGN

Retrospective review.

SETTING

Eight academic level I trauma centers.

PATIENT SELECTION CRITERIA

Adult patients with periprosthetic distal femur fractures at or distal to the anterior flange (OTA/AO 33B-C[VB1]) treated with rIMN or LP.

OUTCOME MEASURES AND COMPARISONS

The primary outcome was reoperation to promote healing or to treat infection (reoperation for elective removal of symptomatic hardware was excluded from this analysis). Secondary outcomes included nonunion, delayed union, fixation failure, infection, overall reoperation rate, distal femoral alignment, and ambulatory status at final follow-up. Outcomes were compared between patients treated with rIMN or LP.

RESULTS

Seventy-one patients treated with rIMN and 224 patients treated with LP were included. The rIMN group had fewer points of fixation in the distal segment (rIMN: 3.5 ± 1.1 vs. LP: 6.0 ± 1.1, P < 0.001) and more patients who were allowed to weight-bear as tolerated immediately postoperatively (rIMN: 45%; LP: 9%, P < 0.01). Reoperation to promote union and/or treat infection was 8% in the rIMN group and 16% in the LP group ( P = 0.122). There were no significant differences in nonunion ( P > 0.999), delayed union ( P = 0.079), fixation failure ( P > 0.999), infection ( P = 0.084), or overall reoperation rate ( P > 0.999). Significantly more patients in the rIMN group were ambulatory without assistive devices at final follow-up (rIMN: 35%, LP: 18%, P = 0.008).

CONCLUSIONS

rIMN of extreme distal periprosthetic femur fractures has similar complication rates compared with LP, with a possible advantage of earlier return to weight-bearing. Surgeons can consider this treatment strategy in all fractures with stable implants and amenable prosthesis geometry, even extreme distal fractures.

LEVEL OF EVIDENCE

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

Weight-bearing Restrictions after Distal Femur Fractures - Review of Current Literature

The incidence of distal femur fractures increases in the geriatric patient. The primary treatment goal in these fractures is early mobilisation to prevent secondary injuries associated with immobility. In light of the increasing spectrum of therapeutic options for postoperative fracture treatment, including double plating, nail-plate combination and distal femur replacement as postoperative treatments, weight-bearing recommendations are becoming increasingly important. The aim of this study was thus to analyse the weight-bearing recommendations and associated therapy results within the literature of the past 9 years and compare the recommendations to our own approach.

Weight-bearing Guidelines for Common Geriatric Upper and Lower Extremity Fractures

PURPOSE OF REVIEW

The purpose of this review paper is to summarize current weight-bearing guidelines for common geriatric fractures, around weight-bearing joints, of the upper and lower extremities.

RECENT FINDINGS

There is an increasing amount of literature investigating the safety and efficacy of early weight-bearing in geriatric fractures, particularly of the lower extremity. Many recent studies, although limited, suggest that early weight-bearing may be safe for geriatric distal femur and ankle fractures. Given the limited data pertaining to early weight-bearing in geriatric fractures, it is difficult to establish concrete weight-bearing guidelines in this population. However, in the literature available, early weight-bearing appears to be safe and effective across most injuries. The degree and time to weight-bearing vary significantly based on fracture type and treatment method. Future studies investigating postoperative weight-bearing protocols should focus on the growing geriatric population and identify methods to address specific barriers to early weight-bearing in these patients such as cognitive impairment, dependence on caregivers, and variations in post-acute disposition.

Temporary Partial Weight-Bearing Restriction in Elderly Patients Treated With a Plate Fixation After a Distal Femur Fracture had a Negative Long-Term Impact on Gait Recovery

Background

Restricted weight-bearing is still used after lower extremity fracture surgery in elderly patients. The long-term effect on gait recovery in elderly patients with distal femur fractures (DFF) and their ability to comply with the restrictive weight-bearing regime is unknown. This study aimed to investigate the effect of restricted postoperative weight-bearing on gait recovery (actual weight-bearing and cadence) during a 1-year follow-up.

Methods

This study evaluated secondary outcomes from a randomized controlled trial (32 patients ≥65 years, with a traumatic DFF). Internal fixation was achieved using an anatomical lateral plate. Patients were allocated to either immediate full weight-bearing (FWB) or partial weight-bearing (PWB) (30% of body weight) for 8 weeks. Pressure-sensitive sensors (F-scan™ system, Tekscan, Massachusetts, USA) were used to measure weight-bearing and cadence postoperatively and at 8-, 16-, and 52-week follow-ups. Twenty-six patients with at least 1 measurement were included.

Results

There was a statistically significant difference in actual weight-bearing between the PWB and FWB groups postoperatively of 32.3% (95% confidence interval CI, -50.0; -13.0, P < .001) and at the 8-week follow-up of 36.8% (95% CI -61.0; -18.0, P = .01), but not at later follow-ups. The PWB group presented a consistently lower cadence compared to the FWB group, which was statistically significant at the 16-week follow-up with 9.0 steps/min (95% CI -16.2; -1.1, P = .047) and 52-week follow-up with 9.3 steps/min (95% CI -18.0; -3.9, P = .009).

Conclusions

Restricting postoperative weight-bearing in elderly patients with a DFF had a significant effect on postoperative weight-bearing. The effect lingered with a delayed return to FWB and persistent significantly lower cadence in the PWB group. These findings suggest that even temporary weight-bearing restrictions most likely have negative long-term effects on gait function at 1 year and, therefore, cannot be recommended.

Periprosthetic Fractures After a Total Knee Arthroplasty

As the number of total knee arthroplasties performed continues to increase, complications such as postoperative periprosthetic fractures are becoming increasingly more common. Femoral periprosthetic fractures are the most common type of fractures around a total knee arthroplasty, whereas tibial and patellar periprosthetic fractures are infrequent. Treatment principles depend on the bone the fracture is located, the status of the implant fixation, bone stock, and the type of implants available. The Vancouver classification allows for a standardized system to describe and manage these injuries, incorporating these factors. A systematic approach is vital in obtaining the best possible outcomes because complications and mortality rates mimic those of hip fractures.

Surgical approaches to periprosthetic femoral fractures for plate fixation or revision arthroplasty

Periprosthetic femoral fractures are increasing in incidence, and typically occur in frail elderly patients. They are similar to pathological fractures in many ways. The aims of treatment are the same, including 'getting it right first time' with a single operation, which allows immediate unrestricted weightbearing, with a low risk of complications, and one that avoids the creation of stress risers locally that may predispose to further peri-implant fracture. The surgical approach to these fractures, the associated soft-tissue handling, and exposure of the fracture are key elements in minimizing the high rate of complications. This annotation describes the approaches to the femur that can be used to facilitate the surgical management of peri- and interprosthetic fractures of the femur at all levels using either modern methods of fixation or revision arthroplasty.

Effects of Early Weight-Bearing Treadmill Training Combined with Pre-Emptive Analgesia on Femoral Fracture Recovery

Background

The effect of pre-emptive analgesia plus early weight-bearing treadmill training (EWBTT) on healing and motor function recovery of femoral shaft fracture is not clear.

Methods

A total of 60 SD male rats were randomly allocated into 4 groups: group A (pre-emptive analgesia with EWBTT), group B (pre-emptive analgesia with delayed weight-bearing treadmill training, DWBTT), group C (pre-emptive analgesia with no weight-bearing), and group D (EWBTT with no pre-emptive analgesia). All rats were molded by internal fixation with Kirschner wire after right femoral shaft fracture. In groups A, B, and C, tramadol was intramuscularly injected 15 minutes before surgery. EWBTT was performed at day 1 postoperatively in groups A and D, and DWBTT was performed at day 14 postoperatively in group B. Oblique plate test was accomplished to assess hindlimb motor function recovery of rats in each group. Status of fracture healing was assessed through digital radiography (DR). Hematoxylin-eosin (HE) staining and immunohistochemistry of bone morphogenetic protein-2 (MBP-2) and vascular endothelial growth factor (VEGF) in callus were performed to explore fracture healing. The expression of BMP-2 and VEGF protein in quadriceps femoris muscle was detected by Western blot technique and mRNA expression of BMP-2 and VEGF in callus ascertained via reverse transcription-polymerase chain reaction (RT-PCR) technique.

Results

For oblique plate test, rats in group A outperformed those in groups B and C at all time points after operation. DR image revealed that large numbers of callus growth, blurred fracture line, and obvious continuous callus passing through the fracture line can be found in group A at day 28 postoperatively, which is the best healing status among all groups. HE staining of callus confirmed the optimal effect of healing for rats in group A. VEGF and BMP-2 expression by immunohistochemistry showed a significantly higher positive score for callus in group A while those in group C being the lowest at all time points postoperatively. Significantly higher expression level of VEGF and BMP-2 protein was detected in quadriceps femoris muscle from group A, which exceeded those in all other groups at all time points. RT-PCR testing proved the highest expression of BMP-2 and VEGF mRNA in callus of rats from group A, significantly higher than those of other groups.

Conclusions

Both pre-emptive analgesia and EWBTT can effectively invoke the expression of VEGF and BMP-2 and promote recovery of hindlimb locomotor function in rats with femoral fracture, and the combination of them leads to more superior results.

Distal Femoral Replacement for Fractures Allows for Early Mobilization with Low Complication Rates: A Multicenter Review

Periprosthetic fractures around a total knee arthroplasty (TKA), comminuted and intra-articular femur fractures, or fracture nonunions in osteoporotic bone represent technically challenging problems. This is particularly true when the fracture involves a loose femoral component or the pattern results in suboptimal fixation potential. These clinical indications often arise in an older and comorbid patient population in whom a principal goal of treatment includes allowing for early mobilization. Limited data indicate that arthroplasty via distal femoral replacement (DFR) is a reasonable alternative to open reduction and internal fixation, allowing for early ambulation with low complication rates. We performed a retrospective review of trauma and arthroplasty surgeries at three tertiary referral institutions. Adult patients treated for the above with a DFR were included. Patients with active infection, open and/or high-energy injuries and revisions unrelated to fracture were excluded. Patient demographics, treatment details, and outcomes were assessed. Between 2002 and 2017, 90 DFR's were performed for the above indications with a mean follow-up of 24 months. Postoperatively, 80 patients (88%) were allowed to weight bear as tolerated, and at final follow-up, 9 patients (10%) remained dependent on a wheelchair. The average arc of motion at final follow-up was 95 degrees. There were seven (8%) implant-related complications requiring secondary surgeries: two infections, one with associated component loosening; one fracture of the hinge mechanism and one femoral component failure in conjunction with a patellofemoral dislocation (both requiring revision); one case of patellofemoral arthrosis in a patient with an unresurfaced patella; one periprosthetic fracture with associated wound dehiscence; and one case of arthrofibrosis. In each of these cases, only modular components of the DFR were exchanged. All nonmodular components cemented into the femur or tibia were retained. DFR provides a viable reconstruction option in the treatment of acute distal femur fractures, periprosthetic femur fractures, and fracture nonunions. We noted that in an elderly patient population with high comorbidities, the complication and secondary surgery rates remained relatively low, while allowing for immediate weight bearing.

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

BACKGROUND

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

TRIAL REGISTRATION NUMBER

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

Smart fracture plate for quantifying fracture healing: Preliminary efficacy in a biomechanical model

The diagnosis of fracture nonunion following plate osteosynthesis is subjective and frequently ambiguous. Initially following osteosynthesis, loads applied to the bone are primarily transmitted through the plate. However, as callus stiffness increases, the callus is able to bear load proportional to its stiffness while forces through the plate decrease. The purpose of this study was to use a "smart" fracture plate to distinguish between phases of fracture healing by measuring forces transmitted through the plate. A wireless force sensor and small adapter were placed on the outside of a distal femoral locking plate. The adapter converts the slight bending of the plate under axial load into a transverse force which is measurable by the sensor. An osteotomy was created and then plated in the distal femur of biomechanical Sawbones. Specimens were loaded to simulate single-leg stance first with the osteotomy defect empty (acute healing), then sequentially filled with silicone (early callus) and then polymethyl methacrylate (hard callus). There was a strong correlation between applied axial load and force measured by the "smart" plate. Data demonstrate statistically significant differences between each phase of healing with as little as 150 N of axial load applied to the femur. Forces measured in the plate were significantly different between acute (100%), early callus (66.4%), and hard callus (29.5%). This study demonstrates the potential of a "smart" fracture plate to distinguish between phases of healing. These objective data may enable early diagnosis of nonunion and enhance outcomes for patients.

Reliability of current classification systems for periprosthetic distal femur fractures

INTRODUCTION

This study aims to determine which Periprosthetic Distal Femur Fracture (PDFF) classification system is the most reliable. The secondary aim was to determine which classification system correlated most accurately with the surgical management recommended and delivered.

METHODS

Between 2011 and 2019, 83 patients with 83 PDFFs that extended to the femoral component of a total knee arthroplasty (TKA) were retrospectively identified from a trauma database. Minimum follow-up was 1 year. Age, BMI, time from TKA, operative management, and Nottingham Hip Fracture Scores were collected, and AP and lateral radiographs used to classify all fractures using seven established classification systems by two observers blinded to management. In patients treated operatively (n = 69), preoperative radiographs were reviewed by two surgeons with expertise in trauma and knee revision who recommended fixation or distal femoral replacement (DFR) requirement.

RESULTS

Mean age was 80.7 years (SD9.4) and 50 (84.7%) were female. PDFFs occurred at a mean 9.5 years (SD5.2) after primary TKA. Mean follow-up was 3.8 years (SD2.9). Management was fixation in 47, DFR in 22 and non-operative for 14. The Fakler classification demonstrated highest interobserver reliability (ICC=0.948), followed by the Rorabeck (ICC=0.903), UCS (ICC=0.850) and Chen (ICC=0.906). The Neer classification demonstrated weakest agreement (ICC=0.633). Overall accuracy of predicting DFR requirement (as determined by two experts) was highest for the Fakler system (83.9%). Compared with actual management delivered the Rorabeck system was most accurate (94.1%). Multivariate regression demonstrated that the ultimate need for DFR (n = 22) was independently associated with medial comminution (HR 2.66 (1.12-6.35 95%CI), p = 0.027) and fractures distal to the anterior flange and posterior condyle of the femoral component (HR 2.45 (1.13-5.31), p = 0.024).

CONCLUSION

The Fakler classification showed highest interobserver agreement and was most accurately predictive of the management recommended by two experts. No classification system accurately predicted the fractures that required DFR, and none included medial comminution which was independently associated with DFR requirement. There remains a need for a PDFF classification system that reliably guides operative management of PDFFs.

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

Introduction

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

Methods

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

Results

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

Conclusions

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

Early Weight Bearing after Distal Femur Fracture Fixation

Objectives

To assess outcomes following early weight bearing after distal femur fracture fixation with locked lateral plating.

Design

Retrospective cohort study

Setting

Two Level 1 Academic Trauma Centers.

Patients/Participants

Patients 18 years and older with distal femur fractures treated with locked lateral plating

Intervention

Early full weight bearing (defined as less than 30 days from date of surgery) versus restricted post-operative weight bearing

Main Outcome Measurements

Composite complication comprising malunion, nonunion, surgical site infection, re-admission, or death

Results

270 distal femur fractures were reviewed, with 165 meeting inclusion criteria. 21 patients had been allowed early full weight bearing. Fractures were divided into two groups based on when full weight bearing was allowed post-operatively. The two groups had similar fractures as determined by the distribution of AO distal femur fracture and Su periprosthetic femur fracture classifications. The early weight bearing group was significantly older and more comorbid. Despite being older, more comorbid, and allowed early full weight bearing on their fracture fixation construct, there was no difference in the rate of composite complications between groups.

Conclusion

Our data contributes to the small, but growing body of literature that has found no increased rate of fracture related complications in surgically treated distal femur fractures allowed early post-operative weight bearing.

Level of Evidence

Therapeutic Level III Study.

To Fix or Revise: Differences in Periprosthetic Distal Femur Fracture Management Between Trauma and Arthroplasty Surgeons

INTRODUCTION

This study sought to determine the effect of trauma fellowship training on the surgical decision to fix or revise to distal femoral replacement in periprosthetic distal femur fractures.

METHODS

An anonymous online survey including nine cases of geriatric periprosthetic distal femur fractures was distributed through the Orthopaedic Trauma Association website. Respondents were asked whether they would recommend fixation or revision to distal femoral replacement. Fractures were classified by the location relative to the anterior flange (proximal or distal) and the presence or absence of comminution. Recommendations were compared between type of fellowship completed (trauma, arthroplasty, or both), practice setting, and number of periprosthetic distal femur fractures treated monthly.

RESULTS

One hundred fifty-one surgeon survey responses were included. Completion of a trauma fellowship was associated with a higher likelihood of recommending fixation for any periprosthetic distal femur fracture compared with arthroplasty training (odds ratio [OR] 2.55, 95% confidence interval [CI] 1.97 to 3.29; P < 0.0001). Disagreement was significant for comminuted proximal (OR 6.90, 95% CI 3.24 to 14.68; P < 0.0001), simple distal (OR 20.90, 95% CI 6.41 to 67.71; P < 0.001), and comminuted distal fractures (OR 2.47, 95% CI 1.66 to 3.68; P < 0.0001). Dual fellowship-trained surgeons were less likely to recommend fixation than surgeons who completed a trauma fellowship alone (OR 0.60, 95% CI 0.39 to 0.93; P = 0.027) and more likely to recommend fixation than surgeons who completed an arthroplasty fellowship alone (OR 1.70, 95% CI 1.13 to 2.63; P = 0.012). Surgeons who treat three or more periprosthetic distal femur fractures monthly showed a significant preference for fracture fixation compared with lower volume surgeons (OR 2.45, 95% CI 1.62 to 3.68; P < 0.0001).

DISCUSSION

Fellowship-trained trauma surgeons show a notable preference for fracture fixation over distal femoral replacement for periprosthetic distal femur fractures, as compared with arthroplasty-trained surgeons. Additional research is needed to clarify surgical indications that maximize outcomes for these injuries.

Distal Femur Replacement Versus Open Reduction and Internal Fixation for Treatment of Periprosthetic Distal Femur Fractures: A Systematic Review and Meta-Analysis

OBJECTIVE

To compare complications and functional outcomes of treatment with primary distal femoral replacement (DFR) versus open reduction and internal fixation (ORIF).

DATA SOURCES

PubMed, Embase, and Cochrane databases were searched for English language studies up to May 19, 2020, identifying 913 studies.

STUDY SELECTION

Studies that assessed complications of periprosthetic distal femur fractures with primary DFR or ORIF were included. Studies with sample size ≤5, mean age <55, nontraumatic indications for DFR, ORIF with nonlocking plates, native distal femoral fractures, or revision surgeries were excluded. Selection adhered to the PRISMA criteria.

DATA EXTRACTION

Study quality was assessed using previously reported criteria. There were 40 Level IV studies, 17 Level III studies, and 1 Level II study.

DATA SYNTHESIS

Fifty-eight studies with 1484 patients were included in the meta-analysis. Complications assessed {incidence rate ratio [IRR] [95% confidence interval (CI)]: 0.78 [0.59-1.03]} and reoperation or revision [IRR (95% CI): 0.71 (0.49-1.04)] were similar between the DFR and ORIF cohorts. The mean knee range of motion was greater in the ORIF cohort (DFR: 90.47 vs. ORIF: 100.36, P < 0.05). The mean Knee Society Score (KSS) (DFR: 79.41 vs. ORIF: 82.07, P = 0.35) and return to preoperative ambulatory status were similar [IRR (95% CI): 0.82 (0.48-1.41)].

CONCLUSIONS

In comparing complications among patients treated for periprosthetic distal femur fracture with DFR or ORIF, there was no difference between the groups. There were also no differences in functional outcomes, although knee range of motion was greater in the ORIF group. This systematic review and meta-analysis highlights the need for future prospective trials evaluating the outcomes of these divergent treatment strategies.

LEVEL OF EVIDENCE

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

A Comparison of Acute Complications and Mortality Between Geriatric Knee and Hip Fractures: A Matched Cohort Study

INTRODUCTION

To compare acute complication and mortality rates for operatively treated, closed, isolated, low-energy geriatric knee fractures (distal femur [DFF] or tibial plateau [TPF]) with hip fractures (HFs).

METHODS

This is a retrospective cohort study using the American College of Surgeons National Surgical Quality Improvement Program. We identified all patients ≥ 70 years from 2011 to 2016 who underwent surgery for DFF, TPF, or HF. We recorded patient demographics, functional status, complications, and mortality. We matched DFF:TPF:HF patients on a 1:1:10 ratio based on age, sex, body mass index, baseline functional status, and comorbidity. We used the chi square, Fisher exact, and Mann Whitney U tests to compare unadjusted differences between groups and multivariable logistic regression to compare the risk of complications, readmission, or death while adjusting for relevant covariates.

RESULTS

When compared with HF, patients in the DFF and TPF groups had longer length of stay and time to index surgery and were more likely to be discharged home. The rate of deep vein thrombosis was significantly higher in the TPF group (TPF = 3.9%, DFF = 1.3%, and HF = 1.2%, P = 0.005).

CONCLUSION

Geriatric knee fractures pose a similar risk of acute complications, mortality, and readmission compared with patients with HF. Future studies investigating strategies to decrease risk in this patient cohort are warranted.

LEVEL OF EVIDENCE

Therapeutic Level III.

Interprosthetic femoral fractures managed with modern distal femoral locking plates: 10 years' experience at a UK major trauma centre

INTRODUCTION

Interprosthetic femoral fractures (IFF) are rare but increasing with an ageing population. Operative management is challenging and there is currently a paucity of outcome data in literature. The purpose of this study was to evaluate outcomes of IFFs managed with modern distal femoral locking plates, in a larger sample size than previously published.

METHOD

This retrospective study reviewed 49 closed IFFs in 48 patients at a major trauma center from 2009 to 2019 occurring between previous total hip arthroplasty (n=38), hemi hip arthroplasty (n=3), dynamic hip screw (n=6) or cephalomedullary nail (n=2) and total knee arthroplasty. They were managed with Minimally Invasive Plate Osteosynthesis (MIPO) employing modern biological fixation techniques and stabilised with VA-LCP Condylar (Synthes; n=28) or Peri-Loc (S&N; n=21) plate. Clinical and radiographic outcomes were measured.

RESULTS

The majority of fractures were in female patients (80%), who were elderly (average 83 years), and comorbid (55% ASA grade 3 or 4). Most fractures were Pires type IIA and OTA/AO type 33A. Average plate spanning femur was 16 holes, with average working length of 6 holes. 86% had unrestricted weight bearing immediately post operatively. 31 fractures reached radiological (n=25) or clinical (n=6) union. 13 patients died with 2 lost to follow up. There were 3 non-unions, with implant failure occurring before 4 months in all 3. We present a union rate of 91% (n=31/34).

CONCLUSION

IFFs are occurring with increasing frequency in a frail elderly population. In patients with IFFs, MIPO and biological fixation techniques using modern distal femoral locking plates can achieve high rate of union when combined with immediate unrestricted weight bearing postoperatively.

Immediate weight-bearing is safe following lateral locked plate fixation of periprosthetic distal femoral fractures

PURPOSE

This study aimed to determine whether unrestricted weight-bearing as tolerated (WBAT) following lateral locking plate (LLP) fixation of periprosthetic distal femoral fractures (PDFFs) is associated with increased failure and reoperation, compared with restricted weight-bearing (RWB).

MATERIALS AND METHODS

In a retrospective cohort study of consecutive patients with unilateral PDFFs undergoing LLP fixation, patients prescribed WBAT were compared with those prescribed 6 weeks of RWB. The primary outcome measure was reoperation. Kaplan-Meier and Cox multivariable analyses were performed.

RESULTS

There were 43 patients (mean age 80.9 ± 11.7 years, body mass index 26.8 ± 5.7 kg/m² and 86.0% female): 28 WBAT and 15 RWB. There were more interprosthetic fractures in the RWB group (p = 0.040). Mean follow-up was 3.8 years (range 1.0-10.4). Eight patients (18.6%) underwent reoperation. Kaplan-Meier analysis demonstrated no difference in 2-year survival between WBAT (80.6%, 95% CI 65.3-95.9) and RWB (83.3%, 95% CI 62.1-100.0; p = 0.54). Cox analysis showed increased reoperation risk with medial comminution (hazard ratio 10.7, 95% CI 1.5-80; p = 0.020) and decreased risk with anatomic reduction (hazard ratio 0.11, 95% CI 0.01-1.0; p = 0.046). Immediate weight-bearing did not significantly affect the risk of reoperation compared with RWB (relative risk 1.03, 95% CI 0.61-1.74; p = 0.91).

CONCLUSIONS

LLP fixation failure was associated with medial comminution and non-anatomic reductions, not with postoperative weight-bearing. Medial comminution should be managed with additional fixation. Weight-bearing restrictions additional to this appear unnecessary and should be avoided.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Management of low periprosthetic distal femoral fractures

AIMS

Debate continues regarding the optimum management of periprosthetic distal femoral fractures (PDFFs). This study aims to determine which operative treatment is associated with the lowest perioperative morbidity and mortality when treating low (Su type II and III) PDFFs comparing lateral locking plate fixation (LLP-ORIF) or distal femoral arthroplasty (DFA).

METHODS

This was a retrospective cohort study of 60 consecutive unilateral (PDFFs) of Su types II (40/60) and III (20/60) in patients aged ≥ 60 years: 33 underwent LLP-ORIF (mean age 81.3 years (SD 10.5), BMI 26.7 (SD 5.5); 29/33 female); and 27 underwent DFA (mean age 78.8 years (SD 8.3); BMI 26.7 (SD 6.6); 19/27 female). The primary outcome measure was reoperation. Secondary outcomes included perioperative complications, calculated blood loss, transfusion requirements, functional mobility status, length of acute hospital stay, discharge destination and mortality. Kaplan-Meier survival analysis was performed. Cox multivariate regression analysis was performed to identify risk factors for reoperation after LLP-ORIF.

RESULTS

Follow-up was at mean 3.8 years (1.0 to 10.4). One-year mortality was 13% (8/60). Reoperation was more common following LLP-ORIF: 7/33 versus 0/27 (p = 0.008). Five-year survival for reoperation was significantly better following DFA; 100% compared to 70.8% (95% confidence interval (CI) 51.8% to 89.8%, p = 0.006). There was no difference for the endpoint mechanical failure (including radiological loosening); ORIF 74.5% (56.3 to 92.7), and DFA 78.2% (52.3 to 100, p = 0.182). Reoperation following LLP-ORIF was independently associated with medial comminution; hazard ratio (HR) 10.7 (1.45 to 79.5, p = 0.020). Anatomical reduction was protective against reoperation; HR 0.11 (0.013 to 0.96, p = 0.046). When inadequately fixed fractures were excluded, there was no difference in five-year survival for either reoperation (p = 0.156) or mechanical failure (p = 0.453).

CONCLUSION

Absolute reoperation rates are higher following LLP fixation of low PDFFs compared to DFA. Where LLP-ORIF was well performed with augmentation of medial comminution, there was no difference in survival compared to DFA. Though necessary in very low fractures, DFA should be used with caution in patients with greater life expectancies due to the risk of longer term aseptic loosening. Cite this article: Bone Joint J 2021;103-B(4):635-643.

Incidence of nonunion after surgery of distal femoral fractures using contemporary fixation device: a meta-analysis

PURPOSE

Nonunion is the most frequent cause of reoperation and is associated with high morbidity after distal femur fracture (DFF). We examined the rates of nonunion requiring reoperation after fixation for DFF using a locking compression plate (LCP) or retrograde intramedullary nail (RIMN).

METHODS

We included four studies comparing LCP and RIMN and 38 single-cohort studies reporting LCP or RIMN. In total, 2156 femurs were included and 166 non-unions were detected. We conducted a pair-wise meta-analysis (with a fixed-effects model) on the four comparative studies and a proportional meta-analysis on the 38 articles to estimate the nonunion rate. We performed sensitivity analysis by comparing studies using LCP with less invasive surgical systems (LISS) with those that used RIMN.

RESULTS

The pairwise meta-analysis showed a similar nonunion rate between the groups [odds ratio: 1.02; 95% confidence interval (CI) 0.94-1.11, p = 0.633]. According to proportional meta-analysis, the pooled prevalence of nonunion was 5% (95% CI 4-7) totally, 6% (95% CI 4-8) in the LCP group, and 4% (95% CI 2-6) in the RIMN group (heterogeneity: p = 0.105). According to the sensitivity analysis, there was no difference in the union rate. The pooled prevalence of nonunion from sensitivity analysis was 4 % (95% CI, 3-5); it was 4% (95% CI, 3-6) in LCP with LISS and was 4% (95% CI, 2-6) in RIMN group (heterogeneity: p = 0.941).

CONCLUSION

Approximately 5% of patients who underwent LCP or RIMN fixation developed nonunion. Therefore, LCP and RIMN are effective DFF techniques and mastering one of them is essential.

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.

Contradictory working length effects in locked plating of the distal and middle femoral fractures-a biomechanical study

BACKGROUND

Working length have been reported to affect the plate stress and fixation stiffness. However, the results of previous studies have been controversial. The present study was to determine working length effects on different locations of femoral bone gap.

METHODS

Five composite femurs with wide bone gaps at five levels (G1, 2, 3, 5, and 7), were fixed with locking plates. G1-3, G5 and G7 represented gaps at distal femur, distal-middle femur and middle femur respectively. Strain gauges were applied near the screw holes. The plate-bone constructs were loaded through a hemicylinder on the femoral head with total constraints at the distal femur. The micro-strains, axial stiffness and interfragmentary motions were recorded. Then the locking screws were removed one by one and the tests were re-run. The working length effects were compared and correlated.

FINDINGS

In distal femurs (G1-3), long working length was negatively correlated with the highest strains (r = -0.97, -0.95 and - 0.95, p < 0.01) and axial stiffness (r = -1, -0.96 and -0.99, p < 0.01). In distal-middle femurs (G5), as the working length increased, the highest strain decreased initially and then increased (r = 0.81, p = 0.026) and the axial stiffness decreased (r = -0.98, p < 0.01). In middle femurs (G7), the highest strain and gap motions were much higher than that in the other groups and not significantly correlated with the working length change.

INTERPRETATION

Long working length could reduce the highest plate strain in distal femurs, but had no significant effects in middle femurs. The working length effects were markedly affected by the loading and boundary conditions.

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.

Evaluation of callus formation in distal femur fractures after carbon fiber composite versus stainless steel plate fixation

INTRODUCTION

Carbon-fiber-reinforced polyetheretherketone (CFR) composite plates have a more favorable stress modulus than stainless steel (SS) plates that may confer an advantage to bridge plating. The purpose of this study was to compare callus formation after CFR and SS plating of distal femur fractures.

METHODS

A retrospective review identified distal femoral fractures treated with CFR (n = 10) and SS (n = 21) plate fixation. Callus formation was measured using the modified Radiographic Union Score for Tibia (mRUST) at 3- and 6-month follow-up by three orthopedic trauma surgeons. Loss of alignment, implant failure, and revision surgeries were reviewed.

RESULTS

At 3 months, the mRUST in the CFR and SS groups was 9.0 (range, 6.3-12.3) and 6.9 (range, 4.3-11.7), respectively (p = 0.01). At 6 months, the mRUST in the CFR and SS groups was 11.4 (range, 7.7-16.0) and 10.5 (range, 6.0-15.7), respectively (p = 0.3). CFR and SS groups had a loss of fracture alignment in 1 (10%) and 1 (5%) patient, respectively (p = 0.5), and an unplanned revision surgery in 0 (0%) and 3 (15%) patients, respectively (p = 0.2). All three revisions surgeries in the SS group were for nonunion repair.

CONCLUSIONS

Treatment of distal femur fractures with CFR versus SS plating resulted in greater callus formation at 3 months. At 6 months, there was no difference in callus formation between groups. A larger series of patients is necessary to determine if the observed early increased callus formation confers a benefit to clinical outcomes.

LEVEL OF EVIDENCE

Therapeutic level III.

Comparison of the Effects of Proximal Humeral Internal Locking System (PHILOS) Alone and PHILOS Combined with Fibular Allograft in the Treatment of Neer Three- or Four-part Proximal Humerus Fractures in the Elderly

Objective

To compare and analyze the clinical outcomes of the proximal humeral internal locking system (PHILOS) alone and the PHILOS combined with fibular allograft in the treatment of Neer three‐ and four‐part proximal humerus fractures (PHF) in the elderly.

Methods

From January 2014 to January 2018, a total of 42 elderly patients with Neer three‐ or four‐part PHF admitted to our hospital were randomly divided into observation group and control group, with 21 patients in each group. The observation group was treated with the PHILOS combined with fibular allograft. The control group was treated with the PHILOS alone. Perioperative parameters and fracture classification were recorded in the two groups. Function results were assessed by Visual Analog Scale (VAS), Constant‐Murley score (CMS), American Shoulder and Elbow Surgeons (ASES) score, and the Disability of Arm‐Shoulder‐Hand (DASH) score. Radiological results were evaluated using the neck‐shaft angle (NSA) and humeral head height (HHH), and complications were also recorded in each group.

Results

There were no significant differences between the two groups in terms of preoperative status, age, gender, cause of trauma, fracture site, and fracture classification. The average follow‐up time was 12 months. At the last follow‐up, the VAS and DASH observation groups were lower than the control group, and there was significant difference between the two groups (P < 0.05). The CMS and ASES were higher in the observation group than the control group, and there was significant difference between the two groups (P < 0.05). The mean difference in the NSA and HHH were lower in the observation group than the control group, and there was a significant difference between the two groups (P < 0.05). There was one postoperative complication in the observation group, which was humeral head avascular necrosis (AVN). There were seven postoperative complications in the control group, including three cases of humeral head collapse and three cases of screw cutout and one case of humeral head AVN. The incidence of postoperative complications in the observation group was significantly lower than the control group (P < 0.05), there was a significant difference between the two groups.

Conclusions

For Neer three‐ or four‐part PHF in the elderly patients, PHILOS fixation with fibular allograft shows satisfactory short‐term results with respect to humeral head support and maintenance of reduction, and may reduce the incidence of complications associated with fixation using a PHILOS alone.

Surgical Treatment of Distal Femur Fractures in Geriatric Patients

INTRODUCTION

The treatment of distal femur fractures in geriatric patients is challenging and has a high perioperative morbidity and mortality. Treatments have evolved significantly in the past decades. The aim of our study was to analyze local and systemic morbidity and mortality, as well as functional results in this frail cohort treated with distal femur locking plates.

MATERIALS AND METHODS

In this single-institution case series, we retrospectively analyzed the data of patients aged 65 years and older with fractures of the distal femur between March 2013 and March 2018. All patients were operated with distal femur locking plates. Points of interest included perioperative morbidity, mortality, weight-bearing status, and care-dependency after hospital discharge.

RESULTS

We assessed 49 patients (median age: 86.5 years) with 52 distal femur fractures (AO type A 77%, type C 15%, type B 8%). A total of 30 (58%) periprosthetic fractures with 4 (8%) interimplant femur fractures were documented. The perioperative morbidity was 64%, and the 3-month and 1-year mortality rates were 29% and 35%, respectively. The local complication rate was 6% with no documented implant failure. Of the patients who were living at home before the surgery, 62% required long-term accommodation in residential or nursing homes after dicharge from the hospital or short-term rehabilitation.

CONCLUSIONS

Geriatric patients with distal femur fractures face a high perioperative mortality. Osteosynthesis with distal femur locking plates is a reliable technique that can be used in various fracture patterns including periprosthetic and interimplant fractures.

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.

Outcomes of locking plate fixation with fibular allograft augmentation for proximal humeral fractures in osteoporotic patients

Aims

The aim of this study was to evaluate the clinical and radiological outcomes of locking plate fixation, with and without an associated fibular strut allograft, for the treatment of displaced proximal humeral fractures in elderly osteoporotic patients.

Patients and Methods

We undertook a retrospective comparison of two methods of fixation, using a locking plate without an associated fibular strut allograft (LP group) and with a fibular allograft (FA group) for the treatment of these fractures. The outcome was assessed for 52 patients in the LP group and 45 in the FA group, with a mean age of 74.3 years (52 to 89), at a mean follow-up of 14.2 months (12 to 19). The clinical results were evaluated using a visual analogue scale (VAS) score for pain, the Constant score, the American Shoulder and Elbow Surgeons (ASES) score, and the range of movement. Radiological results were evaluated using the neck-shaft angle (NSA) and humeral head height (HHH).

Results

The mean forward elevation in the LP and FA groups was 125.3° (sd 21.4) and 148.9° (sd 19.8), respectively (p = 0.042), while other clinical factors showed no statistically significant differences between the groups. The changes in NSA and HHH immediately after the operation and at final follow-up were significantly better in the FA group than in the LP group (p = 0.015 and p = 0.021, respectively).

Conclusion

For comminuted proximal humeral fractures in osteoporotic patients, locking plate fixation with a fibular strut allograft shows satisfactory short-term results with respect to humeral head support and maintenance of reduction, and may reduce the incidence of complications associated with fixation using a locking plate alone. Cite this article: Bone Joint J 2019;101-B:260–265.

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.

Screw head plugs increase the fatigue strength of stainless steel, but not of titanium, locking plates

Objectives

Screw plugs have been reported to increase the fatigue strength of stainless steel locking plates. The objective of this study was to examine and compare this effect between stainless steel and titanium locking plates.

Methods

Custom-designed locking plates with identical structures were fabricated from stainless steel and a titanium alloy. Three types of plates were compared: type I unplugged plates; type II plugged plates with a 4 Nm torque; and type III plugged plates with a 12 Nm torque. The stiffness, yield strength, and fatigue strength of the plates were investigated through a four-point bending test. Failure analyses were performed subsequently.

Results

For stainless steel, type II and type III plates had significantly higher fatigue strength than type I plates. For titanium, there were no significant differences between the fatigue strengths of the three types of plates. Failure analyses showed local plastic deformations at the threads of screw plugs in type II and type III stainless steel plates but not in titanium plates.

Conclusion

The screw plugs could increase the fatigue strength of stainless steel plates but not of titanium plates. Therefore, leaving screw holes open around fracture sites is recommended in titanium plates.

Cite this article: L-W. Hung, C-K. Chao, J-R. Huang, J. Lin. Screw head plugs increase the fatigue strength of stainless steel, but not of titanium, locking plates. Bone Joint Res 2018;7:629–635. DOI: 10.1302/2046-3758.712.BJR-2018-0083.R1.

Radiographic and Clinical Outcomes of Periprosthetic Distal Femur Fractures Treated With Open Reduction Internal Fixation

OBJECTIVES

To report outcomes and complications of periprosthetic distal femur fractures (PPDFF) treated with open reduction internal fixation (ORIF) using a plate construct, with or without endosteal augmentation.

DESIGN

Retrospective Case Series.

SETTING

One Level I trauma center and one tertiary care hospital.

PATIENTS/PARTICIPANTS

Forty patients with PPDFFs, treated by 3 surgeons, were identified using an institutional trauma registry. Thirty-two patients with 12 months of clinical and radiographic follow-up were included, and 8 patients were lost to follow-up before 12 months.

INTERVENTION

All patients underwent ORIF of the PPDFF with lateral locked plating, and 11 received additional endosteal augmentation using allograft fibula.

RESULTS

Thirty-two patients were available for the final follow-up. Ninety-four percent of patients achieved union at an average of 6.5 months postoperatively. Twenty-one percent of patients underwent subsequent surgery, with more than half of those being for removal of implants. Anatomic limb alignment was achieved in all cases (no malunions). Almost half of the patients required assistive devices for ambulation in the long term.

CONCLUSIONS

ORIF of PPDFF with direct visualization using periarticular locking plates ± endosteal strut allograft resulted in a 94% union rate and no deep infections. There was no difference in outcomes between groups treated with or without additional endosteal fibular allograft. However, these are catastrophic injuries in frail patients, and 20% of patients either died or were lost to follow-up, and almost half required an assistive device for ambulation after surgery despite restoration of limb alignment.

LEVEL OF EVIDENCE

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

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

OBJECTIVE

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

DESIGN

Retrospective comparative cohort study.

SETTING

ACS Level I trauma center.

PATIENTS/PARTICIPANTS

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

MAIN OUTCOME MEASUREMENTS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

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