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

Technical Factors Contributing to Nonunion in Supracondylar Distal Femur Fractures Treated With Lateral Locked Plating: A Risk-Stratified Analysis

OBJECTIVE

To identify technical factors associated with nonunion after operative treatment with lateral locked plating.

METHODS

DESIGN

Retrospective cohort study.

SETTING

Ten Level I trauma centers.

PATIENT SELECTION CRITERIA

Adult patients with supracondylar distal femur fractures (OTA/AO type 33A or C) treated with lateral locked plating from 2010 through 2019.

OUTCOME MEASURES AND COMPARISONS

Surgery for nonunion stratified by risk for nonunion.

RESULTS

The cohort included 615 patients with supracondylar distal femur fractures. The median patient age was 61 years old (interquartile range: 46 -72years) and 375 (61%) were female. Observed were nonunion rates of 2% in a low risk of nonunion group (n = 129), 4% in a medium-risk group (n = 333), and 14% in a high-risk group (n = 153). Varus malreduction with an anatomic lateral distal femoral angle greater than 84 degrees, was associated with double the odds of nonunion compared to those without such varus [odds ratio, 2.1; 95% confidence interval (CI), 1.1-4.2; P = 0.03]. Malreduction by medial translation of the articular block increased the odds of nonunion, with 30% increased odds per 4 mm of medial translation (95% CI, 1.0-1.6; P = 0.03). Working length increased the odds of nonunion in the medium risk group, with an 18% increase in nonunion per 10-mm increase in working length (95% CI, 1.0-1.4; P = 0.01). Increased proximal screw density was protective against nonunion (odds ratio, 0.71; 95% CI, 0.53-0.92; P = 0.02) but yielded lower mRUST scores with each 0.1 increase in screw density associated with a 0.4-point lower mRUST (95% CI, -0.55 to -0.15; P < 0.001). Lateral plate length and type of plate material were not associated with nonunion. ( P > 0.05).

CONCLUSIONS

Malreduction is a surgeon-controlled variable associated with nonunion after lateral locked plating of supracondylar distal femur fractures. Longer working lengths were associated with nonunion, suggesting that bridge plating may be less likely to succeed for longer fractures.

LEVEL OF EVIDENCE

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

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.

New Classification for Periprosthetic Distal Femoral Fractures Based on Locked-Plate Fixation Following Total Knee Arthroplasty: A Multicenter Study

BACKGROUND

This study aimed to establish a new classification using locked-plate fixation for periprosthetic distal femoral fracture (PDFF) following total knee arthroplasty (TKA) and to determine when dual locked-plate fixation is necessary through defining this classification.

METHODS

One-hundred fifteen consecutive PDFFs that underwent operative treatment were reviewed from 2011 to 2019 with minimum 1-year follow-up. Most PDFFs were fixed with single or dual locked-plate fixations using the minimally invasive plate osteosynthesis technique. Based on preoperative radiographs, PDFFs were classified according to the level of main fracture line relative to the anterior flange of femoral component: type I and II, main fracture line located proximal and distal to the anterior flange; and type III, component instability regardless of fracture line requiring revisional TKA. Furthermore, type II fractures were subclassified based on the direction of fracture beak as follows: type II_L, lateral-beak; type II_M, medial-beak. The incidence, treatment methods, and complications were analyzed according to the classification.

RESULTS

Incidences of type I, II_L, II_M, and III were 64.4%, 8.7%, 24.3%, and 2.6%, respectively. Meanwhile, most PDFFs in type I and II were treated with lateral single locked-plate fixations, except for type II_M, which was treated with either single or dual locked-plate fixations. Overall complications were significantly higher in type II (28.9%) than in type I (10.8%, P = .019). In type II_M, bone union-related complications were significantly higher in single locked-plate fixation (50.0%) than in dual locked-plate fixation (5.6%; P = .013).

CONCLUSION

The new classification provides practical and obvious strategies for the treatment of PDFF following TKA using locked-plate fixation. For type II_M fracture, dual plate fixation is necessary to prevent fixation failure or nonunion.

[Clinical application of lower extremity axial distractor in closed reduction and retrograde intramedullary nail fixation of distal femoral fractures]

Objective

To explore the efficacy and advantages of the lower extremity axial distractor assisted closed reduction and retrograde intramedullary nail internal fixation in the treatment of distal femoral fractures.

Methods

The clinical data of 49 patients with distal femoral fractures treated with retrograde intramedullary nail internal fixation between April 2016 and December 2018 were retrospectively analyzed. According to the different methods of intraoperative reduction, the patients were divided into trial group (29 cases, using lower extremity axial distractor to assist closed reduction) and control group (20 cases, using free-hand retraction reduction). There was no significant difference in general information between the two groups ( P>0.05), such as gender, age, side of injury, cause of injury, and fracture classification. The operation time, intraoperative blood loss, intraoperative fluoroscopy frequency, and callus formation time were recorded and compared between the two groups. The function of the affected limb was evaluated according to the Schatzker-Lambert standard at 1 year after operation.

Results

All patients successfully completed the operation. In the control group, there was 1 case with open reduction and internal fixation, and the rest of the two groups were closed reduction. There was no significant difference in operation time, intraoperative blood loss, and intraoperative fluoroscopy frequency between the two groups ( P>0.05). There was no complication such as vascular or nerve injury and iatrogenic fracture, etc. during and after operation, and the incisions healed by first intention. Except for 2 patients in the trial group who were lost to follow-up at 3 months after operation, the rest of the patients were followed up 12-36 months, with an average of 16.0 months. There was no significant difference in the callus formation time between the two groups ( t=2.195, P=0.145). During the follow-up, postoperative knee joint stiffness occurred in 1 case in the control group, which improved by strengthening the knee joint function exercise and removing the internal fixator; the rest were not found to be associated with delayed or nonunion fractures, knee stiffness, and internal fixation complication. The function of the affected limb was evaluated according to the Schatzker-Lambert standard at 1 year after operation, the trial group achieved excellent results in 22 cases, good in 4 cases, and fair in 1 case, with an excellent and good rate of 96.3%; in the control group, the results were excellent in 16 cases, good in 3 cases, and fair in 1 case, with an excellent and good rate was 95.0%; showing no significant difference in the excellent and good rate between the two groups ( χ ²=0.451, P=0.502).

Conclusion

The lower extremity axial distractor assisted closed reduction and retrograde intramedullary nailing for the treatment of distal femoral fractures is convenient, which has satisfactory efficacy.

Technical difficulties and mechanical failure of distal femoral locking compression plate (DFLCP) in management of unstable distal femoral fractures

Objective of the paper is to portray the technical difficulties and mechanical failure of Distal Femoral Locking Compression Plate in the management of unstable distal femoral fractures. The primary outcome measure was defined as revision surgery due to implant failure with subsequent non-union. Secondary outcome measures were mal-union, delayed union, peri-implant fracture and infection. Functional outcome were evaluated using Schatzker & Lambert criteria. Thirty nine patients were available for final follow up. The rate of revision surgery as primary outcome measure was 7.69%. Mal-union was seen in 5.1%, delayed union in 7.69%, superficial infection in 10.25% and deep infection in 5.1% patients. All except three fractures united following index surgery. Functional outcome as per the Schatzker & Lambert Criteria was excellent in 20.5%, good in 48.7%, fair in 18% and failure in 12.8%. In sight of the findings of our study along with existing literature we propose for creating a fixation construct that is conducive for fracture healing by following principles of locking compression plating and augmenting stability by medial column reconstruction.