Does the type of medial plate fixation matter for supplemental fixation of distal femur fractures manage with a lateral pre-contoured locked plate? A Biomechanical study.

INTRODUCTION: Fixation of distal femur fractures with a lateral pre-contoured locking plate provides stable fixation and is the standard treatment in most cases, allowing early range of motion with a high rate of union. However, in situations, the stability achieved with the lateral plate alone may be insufficient, predisposing to fixation failure. The objective of the study was to compare, in synthetic bone models, the biomechanical behaviour of the fixation with a distal femur lateral pre-contoured locking plate solely and associated with a 3.5 mm proximal humeral locking plate applied upside down or a 4.5 mm helical locking compression plate on the medial side. MATERIAL AND METHODS: A total of 15 solid synthetic left femur samples were used. A metaphysical defect at the level of the medial cortex was simulated. The samples were randomly distributed into three groups equally. All groups received a 4.5/5.0 mm single lateral 9-hole distal femur lateral pre-contoured locking plate. Group 1 had no supplementary plate. Group 2 received a supplementary 6-hole 3.5 mm proximal humeral locking plate and Group 3 received a supplementary 4.5/5.0 mm helical 14-hole narrow locking compression plate. RESULTS: Both supplementary plate types used in groups 2 and 3 contributed to increase the apparent stiffness of the construct, but pairwise comparison showed statically significant difference only between group 1 and 3. No significant difference was observed between groups 2 and 3. CONCLUSION: Both supplementary plates might be considered for improving the fixation in distal femur fracture in selected cases.

The polymicrobial infection affects the infection recurrence rate (not failure) in treating femoral and tibial bone defects with the Masquelet technique-a comparative retrospective analysis of 54 patients with mono- and polymicrobial infections.

INTRODUCTION: This study evaluated whether polymicrobial infection affects reoperation rates due to infection recurrence and treatment failure with the Masquelet technique in infected posttraumatic segmental bone defects of the femur and tibia. METHODS:  We retrospectively analyzed patients treated between 2012 and 2021 in two trauma referral centers. We evaluated demographic data, injury, treatment, infection recurrence, failures, and bone healing rates according to whether the infection was mono- or polymicrobial. After uni-bivariate analysis between patients with polymicrobial and monomicrobial infection, we identified the variables associated with infection recurrence and failure through multivariate analysis. RESULTS:  We analyzed 54 patients, 30 (55.55%) with tibial and 24 (44.44%) femoral segmental bone defects, with a mean follow-up of 41.7 ± 15.0 months. Forty-four (81.48%) presented monomicrobial, and 10 (18.51%) polymicrobial infections. Comparatively, the need for soft tissue reconstruction and the infection recurrence rate was significantly higher in patients with polymicrobial infections. There was no significant difference in the failure rate (20 vs. 6.81% p = 0.23). Multivariable logistic regression analysis identified the polymicrobial infection as the only independent variable associated with infection recurrence (Odds Ratio = 11.07; p = 0.0017). CONCLUSION:  Our analysis suggests that polymicrobial infection is associated with a higher risk of infection recurrence in treating the femur and tibia segmental bone defects with the Masquelet technique. This information can help surgeons to inform patients about this and give them a realistic expectation of the outcome and the possibility of reoperation.

Effectiveness of two-stage revision with commercial polymethylmethacrylate articulated hip spacer: similar outcomes against monomicrobial and polymicrobial hip periprosthetic joint infections.

Background: orthopaedic surgeons still struggle against a devastating complication - periprosthetic joint infection (PJI). A two-stage revision is considered the gold standard for chronic PJI for several authors, with success rates over 90 %. This strategy implies the remotion of the prosthesis and the implantation of an antibiotic-impregnated cement spacer in the joint. The primary objective of this study was to assess the effectiveness of a two-stage revision approach using a commercial prefabricated antibiotic-impregnated cement hip spacer for the treatment of hip PJI regarding monomicrobial and polymicrobial infections. Secondly, to assess risk factors for failure of two-stage revision. Material and methods: we conducted a retrospective study on patients that underwent revision of total hip arthroplasty (THA) between January 2002 and January 20218. We included adult patients with a diagnosis of chronic hip PJI that underwent two-stage revision using a prefabricated gentamicin-impregnated cement of polymethylmethacrylate (PMMA) hip spacer. We assessed whether it was monomicrobial or polymicrobial infections and comorbidities. Treatment success was defined when eradication of the infection was observed and no further procedures or mortality were registered after the second stage. Persistence or recurrence of infection was considered a failure of treatment. Results: the final series consisted of 84 patients treated with the same hip spacer: 60 (71.4 %) monomicrobial and 24 (28.6 %) polymicrobial joint infections with an overall follow-up of 59.0 (36.0-84.0) months. The overall success rate was 90.5 %. Eight (9.5 %) patients failed. Smoking and BMI greater than 30 m kg-2 were identified independent risk factors for failure in multivariate analysis. Conclusion: our study suggests that prefabricated gentamicin-impregnated PMMA spacer is an effective tool for the treatment of PJI, achieving similar outcomes whether it is monomicrobial or polymicrobial infections. Randomized prospective studies are needed to obtain more reliable conclusions.

Does the distal nail position impact the rates of misalignment and bone union in distal tibial fractures?

PURPOSE: This retrospective study aimed to assess the impact of distal nail placement on misalignment and healing rates in distal tibial fractures. METHODS: We reviewed all patients with distal tibial fracture treated with intramedullary nailing between 2015 and 2021, and a minimum follow-up of 12 months. Distal nail positioning was determined according to the Triantafillou zones. We related these positioning zones to misalignments (alignment ≥ 3°) and too bony union disorders (delayed union, non-union). RESULTS: Out of the 62 patients included, 56 (90.3%) show bone union without additional procedure, 3 (4.8%) with dynamization, and 3 (4.8%) showed non-union. Twenty-one (33.8%) presented misalignment, with valgus in the coronal plane being the most frequent (76.19%). In patients with and without misalignment, the most frequent distal nail position was 2-2 in 47.6% and 80.5%, respectively (p = 0.01). In multivariate analysis, distal nail positioning in the 2-2 zone showed a significant protective effect against misalignment (OR 0.18; p = 0.018), while nail positioning in the 3-2 zone generated a significant risk of misalignment (OR 18.55; p = 0.009). CONCLUSION: In intramedullary nailing of distal tibial fractures, distal positioning of the nail slightly lateral to the center of the talus in the coronal plane and slightly posterior in the sagittal plane (zone 2-2) allows high alignment percentages to be obtained. Positioning medial to this point in the coronal plane (zone 3) is associated with more significant misalignment and should be avoided.

Pre-fracture ambulation capacity, Charlson comorbidity index, and dementia as predictors of functional impairment after bipolar hemiarthroplasty for unstable intertrochanteric fracture. A retrospective analysis in 158 octogenarian patients.

Background: the primary purpose of this study was to assess the ambulatory capacity 12 months after surgery in patients that underwent bipolar hemiarthroplasty (BH) due to unstable intertrochanteric fractures (UITF). Secondly, to identify which preoperative variables influenced these modifications. Methods: We retrospectively analyzed a consecutive series of patients older than 80 years with UITF treated with BH between 2010 and 2019. Ambulatory capacity was assessed before surgery, at 3 and 12 months postoperatively, using Koval's classification and the modified Harris Hip Score (mHHS). The registered variables were: gender, age, osteoporosis, Charlson comorbidity index (CCI), ASA classification, body mass index (BMI), and dementia. The identification of variables that impaired postoperative functionality was performed by uni- and multivariate analysis. Results: 158 patients were included with a median age of 87 (range 80-102) years and a follow-up of 29.2 (range 12-56) months. The 1-year overall ambulatory capacity impairment was 28.5% and significantly affected pre-fracture community walkers (p = 0.001). A CCI >4 (OR 2.72; p = 0.044), dementia (OR 14.13; p = 0.0001), and a Koval 2-3 (OR 12.84; p = 0.001) were identified as risk factors for this impairment. Conclusion: Ambulation impairment at one year was 28.5%. The predictive characteristics found in this study help to identify patients with a greater risk of ambulation impairment and to focus rehabilitation plans to reduce this impact.

Periprosthetic fracture management of the proximal femur.

The most common periprosthetic fractures occur around the hip. The most widely used classification is the Vancouver classification, and management requires careful planning and skill in both arthroplasty and fracture surgery. This article presents an overview of the diagnosis, classification, and management of periprosthetic fractures of the proximal femur. This work represents a summary review from Latin American Society Members of the International Orthopaedic Trauma Association.

Antibiotic cement-coated rigid locked nails in infected femoral and tibial nonunion. Reoperation rates of commercial versus custom-made nails.

INTRODUCTION: The objective of this study is to assess bone union, infection control, and reoperation rates in a series of patients with infected femoral or tibial nonunion treated with antibiotic-cement-coated rigid nails and to compare the results obtained with custom-made nails versus commercial nails. METHODS: We retrospectively analyzed a series of consecutive patients with infected nonunion of the femur or the tibia treated with antibiotic-cement-coated rigid nails between January 2010 and 2020. We assessed patients' distinctive characteristics, initial injury, type of nail used (custom-made nail with vancomycin or commercial nail with gentamicin), success rate (bone union + infection control), reoperation rate, and failure rate. Comparative analyses were conducted between reoperated and non-reoperated patients regarding the type of nail used. A multivariate regression analysis was performed to assess the risk variables that impacted reoperation rates. RESULTS: We included 54 patients with 22 (40.74%) infected femoral nonunions and 32 (59.25%) tibial nonunions, who were treated with 38 (70.37%) custom-made antibiotic-cement coated nails and 16 (29.62%) commercial nails. Bone union and infection control were achieved in 51 (94.44%) cases. The reoperation rate was 40.74% (n = 22), and the failure rate was 5.55% (n = 3). The use of custom-made nails was associated with a higher risk of reoperation (Odds Ratio 4.71; 95% Confidence Interval 1.10 - 20.17; p = 0.036). CONCLUSION: Antibiotic-cement-coated nails reached a 94.44% success rate. Nails manufactured in the OR coated with vancomycin cement were associated with a higher risk of reoperation than commercial nails loaded with gentamicin cement. LEVEL OF EVIDENCE: III comparative, observational, non-randomized.

Distal articular involvement in tibial shaft fractures: an evaluation of 125 consecutive cases.

PURPOSE: To report the incidence and morphology of ipsilateral distal articular involvement (DAI) in a consecutive series of tibial shaft fractures. METHOD: A retrospective review was performed on 115 patients who underwent intramedullary nailing for tibia shaft fractures. Ankle evaluations included preoperative radiographs and computed tomography (CT) scans in all patients. RESULTS: Thirty-two patients (27.8%) in our series presented with tibial shaft fractures associated with DAI. Tibial spiral fractures (42A1) were significantly related to DAI (RR: 1788). In 28 (87.5%; 28/32) articular fractures, posterior malleolus fractures (PMF) were present; 22 were isolated, and six (18.8%) occurred in combination with medial malleolus or anterolateral fractures. The remaining (12.5%; 4/32) were isolated medial malleolus fractures. Ten (31.2%; 10/32) articular fractures were occult on the radiographs and only detected on CT scan. CONCLUSION: DAI is common in tibial shaft fractures. CT evaluation is mandatory due to the high number of occult fractures. Although isolated PMF is the most frequent pattern of DAI involvement, 31.3% of the cases exhibited different patterns.

The relevance of the number of distal locking planes and nail to canal ratio in bone healing after intramedullary nailing in tibial shaft fractures.

INTRODUCTION: The objective of this retrospective study was to assess the effect of the nail to canal ratio and the number and configuration of distal locking screws in bone healing in tibial shaft fractures. METHODS: We analyzed 223 consecutive tibial shaft fractures treated with reamed intramedullary nailing between January 2014 and December 2020. We recorded and evaluated the nail to canal ratio (NCR) and the number and configuration of distal locking screws. Median NCR was 0.87 (IQR 0.82-0.94). Ten (4.48%) fractures were treated with one distal locking screw, 173 (77.57%) with two, and 40 (17.93%) with three. Uniplanar fixation was used in 63 (28.25%), biplanar in 150 (67.26%), and triplanar in 10 (4.48%) cases. Uni-, bi-, and multivariate analyses were performed to compare patients who achieved bone union with those who did not. RESULTS: Bone union was achieved in 195 (87.44%) patients. Uni- and bivariate analyses showed that bone union increased significantly with larger NCR (p = 0.0001) and a greater number of locking planes (p = 0.001) and distal screws (p = 0.046). NCR > 0.78 (OR 48.77 CI 95% 15.39-154.56; p = < 0.0001) and distal locking screw configuration (OR 2.91 CI 95% 1.12-9.91; p = 0.046) were identified as independent variables for union. CONCLUSION: Our findings suggest that in tibial shaft fractures treated with intramedullary nailing, NCR should be equal to or greater than 0.79. Additionally, distal locking screws should be used with a biplanar or triplanar configuration.

Culture-negative Peri-prosthetic Joint Infection after Total Hip Arthroplasty Treatment Protocol and Outcomes in Acute and Chronic Cases.

The treatment of culture-negative periprosthetic joint infections (CN PJI) of the hip represents complex entities. We, as a result of this, report on 12 cases. Irrigation and debridement (I&D) with implant retention were performed in acute cases and two-stage revisions in chronic infections. Combined antibiotic therapy was administered in all cases for 12 weeks. Infection control was achieved in all patients with an infection-free rate of 100% at 7.5 years of average follow-up.

Bipolar hemiarthroplasty in unstable intertrochanteric fractures in elderly patients. The predictive value of the Charlson Comorbidity Index in 1-year mortality.

BACKGROUND: Hip fractures have a significant impact on morbidity and mortality in the elderly. Aims: We retrospectively evaluated the predictive role of the Charlson Comorbidity Index (CCI) for 1-year mortality in elderly patients with unstable intertrochanteric hip fractures (ITHF) treated with bipolar hemiarthroplasty. The secondary objective was to identify other relationships, if any, between the variables recorded and mortality. METHODS: We included ≥75-year-old patients with unstable ITHF treated with bipolar hemiarthroplasty. We recorded patient gender, age, Body Mass Index, pre-fracture walking ability (Parker Mobility score, modified Harris Hip Score), America Society of Anesthesiologists (ASA) score, Charlson Comorbidity Index (CCI), time to surgery, time to mobilization, hospital stay, and postoperative complications. Uni- and multivariate logistic regression analysis were performed. Sensitivity and specificity were calculated using a ROC curve. RESULTS: A total of 135 patients with a mean age of 87.34 ± 5.5 years were included. The overall 1-year mortality rate was 18.5%. The CCI (OR 1.64 CI 95% 1.21-2.23; p 0.00821) and postoperative complications (OR 3.5 CI 95% 1.19-10.23 p 0.0202) were identified as independent predictors of 1-year mortality in the univariate regression and confirmed in the multivariate regression. CCI sensitivity to predict 1-year mortality was 80%. CONCLUSION: CCI has shown acceptable sensitivity in the prediction of 1-year mortality in elderly patients with unstable ITHF treated with bipolar hemiarthroplasty. It is of utmost importance to prevent postoperative complications due to their significant impact on 1-year mortality.

Masquelet technique in post-traumatic infected femoral and tibial segmental bone defects. Union and reoperation rates with high proportions (up to 64%) of allograft in the second stage.

Introduction The aim of this study was to describe union, reoperation and failure rates after using the induced membrane (IM) technique with ≥50% allograft over autograft to treat infected femoral and tibial segmental bone defects (SBD). Materials and methods We retrospectively analyzed patients with femoral and tibial SBD treated in our center between 2012 and 2019 using ≥50% allograft over autograft during the second stage of the Masquelet technique. We analyzed the affected bone, defect size, osteosynthesis technique used, time elapsed between the first and second stage of the technique, graft proportions, union time, reoperations, and non-union rates. Results We included 21 patients (61.90% men) with a median age of 41 (range 18-68) years. The tibia was affected in 61.90% (n:13) and the femur in 38.09% (n:8) of the cases. SBD length was 4.5 (range 3.5-14) cm. The median interval between both stages of the technique was 10 (range 6-28) weeks. The proportion of allograft used was 50 % in 10 patients, 51 to 55% in 5 patients, 56 to 59% in 4 patients, and 60 to 64% in 2. The union rate was 95.23% over a median time of 7 (range 6-12) months. There were 3 (14.28%) reoperations: 2 for relapse of infection and 1 for mechanical instability. There was one failure (4.76%). One patient presented non-union and nail break. The median follow-up after the second stage of the technique was 26 (range 13-54) months. Conclusion The use of the induced membrane technique and a high proportion of allograft (up to 64%) achieved similar union and failure rates than those reported for similar series that relied on lower allograft proportions.