Time dedicated to physical activity among medical residents: are there differences based on gender or specialty type?

INTRODUCTION

Physical activity (PA) is associated with positive health outcomes such as prevention of chronic diseases, psychological well-being and improved work performance. Medical residents are subjected to sleep deprivation, extended work schedule and high burnout prevalence. These conditions may lead to the neglect of personal health and the restriction of time dedicated to PA. The objective of the present study was to analyze the time dedicated to PA of medical residents, comparing women vs men residents and surgical vs clinical residents.

METHODS

It is a cross-sectional study performed in a Spanish third-level university hospital. All medical residents from our institution were invited to voluntarily participate in the study answering a web-based questionnaire on June 2022. Data regarding demographics, residency and PA practice was recorded.

RESULTS

The response rate was 20.73% (114/550). The 32.5% of the residents considered themselves to be physically inactive and mean time dedicated to PA in a regular week was 3.62 ± 2.22 h. Men residents dedicated more time to PA than women residents (4.23 ± 2.42 h vs 3.14 ± 1.95 h, p = 0.012) and surgical residents dedicated more time than clinical residents (4.33 ± 2.36 h vs 3.23 ± 2.05 h, p = 0.01).

CONCLUSIONS

One third of the medical residents consider themself physically inactive. Women and clinical residents practice PA less time than men and surgical residents. Efforts should be made to encourage PA among residents, especially in women and non-surgeons.

Osteosarcoma After Total Knee Arthroplasty: A Case Report

CASE

A 79-year-old woman presented with a periprosthetic fracture 8 years after a total knee arthroplasty (TKA). Radiographs demonstrated tibial implant loosening with severe osteolysis. A high-grade osteosarcoma around the prosthesis was diagnosed, and a supracondylar femoral amputation was performed. After 2 years, no complications have occurred.

CONCLUSIONS

A malignant tumor around a TKA is extremely rare. Surgeons should remain vigilant with patients who present with rapidly progressive or very aggressive implant loosening with osteolysis. Owing to its complexity and potentially devastating prognosis, treatment should be guided by a specialist multidisciplinary team. Complex limb salvage procedures or amputation is usually required.

Multiligament knee injuries. Ten years' experience at a public university, level I Trauma Center

PURPOSE

To describe our institutional experience and results in the surgical management of multiligament knee injuries (MLKI).

MATERIALS AND METHODS

Retrospective series of MLKI consecutively operated on at a single, level I Trauma Center. Data on patients' baseline characteristics, injuries, treatments, and outcomes were recorded up to one-year follow-up. Recorded outcomes included the Tegner-Lysholm Knee Scoring Scale (TLKSS), return to work, and patient satisfaction.

RESULTS

MLKI incidence was 0.03% among 9897 orthopedic trauma admissions. Twenty-four patients of mean age 43.6 years were included in analysis. The mean Injury Severity Score was 12.6. Five patients presented with knee dislocations and six had fracture-dislocations, two of them open fractures. There was one popliteal artery injury requiring a bypass and four common peroneal nerve palsies. Staged ligamental reconstruction was performed in all cases. There were seven postoperative complications. The median TLKSS was 80 and, though patient satisfaction was high, and dissatisfaction was largely restricted to recreational activities (only 58.3% satisfied). Seventeen patients returned to their previous employment.

CONCLUSIONS

We found a high aggregation of fracture-dislocations secondary to road traffic accidents. One in four patients experienced complications, particularly stiffness. Complications were more common in cases involving knee dislocation. Most patients had good functional results, but 25% were unable to return to their previous work, which demonstrates the long-lasting sequelae of this injury.

[Translated article] Validation of the Spanish version of the modified Harris score

BACKGROUND AND OBJECTIVES

Modified Harris Hip Score (HHS) is one of the most used scales in the assessment of patients with hip pathology. Although a Spanish cross-cultural adaptation has been recently published, there are many studies supporting its validity yet. Therefore, the aim of this study is to validate the newly adapted Spanish version of the HHS (ES-EHM), comparing it with the WOMAC scale.

MATERIALS AND METHODS

The ES-EHM scale was applied to 100 patients who underwent a total hip replacement, in three different situations: (1) prior to surgery (pre-surgical ES-EHM), (2) after surgery, with at least 2 years of follow up (after surgery ES-EHM), and (3) 6 months after the postsurgical registration (final ES-EHM). WOMAC questionnaire was also applied once. We analysed data of scale main score, pain score, function-related score as well as the mean of pre-surgical, postsurgical and final postsurgical ES-EHM scale, in both the ES-EHM and the WOMAC scales. Parameters of reliability, validity and sensitivity to change were obtained.

RESULTS

Clinically relevant improvement was observed (46.55 points) when comparing pre-surgical and post-surgical ES-EHM scores. However, no differences between postsurgical and final ES-EHM were detected. Even so, strong correlation was obtained between the following: (1) postsurgical ES-EHM and final ES-EHM scores, (2) ES-EHM and WOMAC scores, and (3) pain and function-related parameters of ES-EHM and WOMAC scores. Standardised response mean (SRM) was 2.99, test-retest reliability expressed by the intraclass correlation coefficient was 0.90 and Cronbach index 0.95.

CONCLUSIONS

The Spanish cross-cultural adaptation of the EHM scale shows to be reliable, valid and sensitive to change. Thus, the Spanish medical staff will be able to apply the ES-EHM scale with good scientific support.

Validation of the Spanish version of the modified Harris score

BACKGROUND AND OBJECTIVES

Modified Harris Hip Score (HHS) is one of the most used scales in the assessment of patients with hip pathology. Although a Spanish cross-cultural adaptation has been recently published, there are many studies supporting its validity yet. Therefore, the aim of this study is to validate the newly adapted Spanish version of the HHS (ES-EHM), comparing it with the WOMAC scale.

MATERIALS AND METHODS

The ES-EHM scale was applied to 100 patients who underwent a total hip replacement, in three different situations: (1) prior to surgery (pre-surgical ES-EHM), (2) after surgery, with at least 2 years of follow up (after surgery ES-EHM), and (3) 6 months after the postsurgical registration (final ES-EHM). WOMAC questionnaire was also applied once. We analyzed data of scale main score, pain score, function-related score as well as the mean of pre-surgical, postsurgical and final postsurgical ES-EHM scale, in both the ES-EHM and the WOMAC scales. Parameters of reliability, validity and sensitivity to change were obtained.

RESULTS

Clinically relevant improvement was observed (46.55 points) when comparing pre-surgical and post-surgical ES-EHM scores. However, no differences between postsurgical and final ES-EHM were detected. Even so, strong correlation was obtained between the following: (1) postsurgical ES-EHM and final ES-EHM scores, (2) ES-EHM and WOMAC scores, and (3) pain and function-related parameters of ES-EHM and WOMAC scores. Standardized response mean (SRM) was 2.99, test-retest reliability expressed by the intraclass correlation coefficient was 0.90 and Cronbach index 0.95.

CONCLUSIONS

The Spanish cross-cultural adaptation of the EHM scale shows to be reliable, valid and sensitive to change. Thus, the Spanish medical staff will be able to apply the ES-EHM scale with good scientific support.

[Translated article] Closing wedge high tibial osteotomy: An old-fashioned technique? Survival, clinical and radiological outcomes of a case series analysis

INTRODUCTION

Closing wedge high tibial osteotomy (CW-HTO) is a surgical option for active patients with medial knee pain and mild-moderate osteoarthritis with varus limb deformity. Despite its good reported results, this technique has been losing popularity. The aim of this study was to analyse the survival rate, clinical functional outcomes and radiological results of CW-HTO.

METHODS

It is a retrospective case series study. Seventy patients with primary knee osteoarthritis, operated on between 2010 and 2020 in a single Spanish tertiary hospital using the CW-HTO technique and with a minimum follow-up of 2 years were analysed.

RESULTS

Survival rate was 87.6% and 75.5% after a follow-up of 5 and 10 years respectively. Functional outcomes were good-to-excellent (KSS 77.7/100 and OKS 35.6/48) and good pain control (VAS 3.9/10) and high satisfaction (7.2/10) were achieved. Limb varus malalignment was significantly corrected (mean postoperative HKA angle 177.6° and MPTA 90.7°). However, 30% of patients presented hypocorrection, which was associated with inferior survival, functionality and satisfaction.

CONCLUSION

CW-HTO technique can be useful for patients with knee osteoarthritis and varus limb. It allows to correct varus malalignment while achieving good-to-excellent functional outcomes, good pain control, high patient satisfaction and acceptable medium-long term survival rate. However, it is associated with a non-negligible risk of hypocorrection or medial hinge disruption.

Predictors of first-year postoperative complications after fixation of low-energy ankle fractures: A single-center, retrospective cohort study of 663 consecutive fractures

INTRODUCTION

Rotational ankle fractures are common, have diverse personalities and affect both robust and fragile patients. Postoperative complications are frequent, creating a sizeable economic burden. The primary purpose of this study was to expand current knowledge on predictors of postoperative complications after low-energy ankle fracture fixation.

MATERIALS AND METHODS

A retrospective single-center cohort study was completed of patients undergoing internal fixation OF low-energy ankle fractures. The primary outcome was first-year postoperative complications, classified as major (surgical) or minor (non-surgical). Data on patients, their injuries, and treatments were collected. To identify potential predictors of outcomes, logistic regression methods were used, with a backward-stepwise method used for model fitting.

RESULTS

In total, 663 patients of median age 59 years were analysed. We found a high rate of complications (28.4%), with wound-healing issues and infections predominant. Overall, 14.8% had minor complications, while 13.6% required an unplanned reoperation. On multivariable analysis, the most consistent predictors of complications were older age (OR: 1.02 per year), longer operating time (3.32 per hour), and smoking (2.91).

CONCLUSIONS

Older patients and smokers who sustain fractures requiring more complex surgery are at higher risk of postoperative complications.

Economic evaluation of high tibial osteotomy: Closing wedge is more cost-effective than open wedge technique when analysing the KOOS-12 improvement

PURPOSE

The purpose of this study was to compare the cost-effectiveness of two techniques for performing a knee valgus osteotomy: opening wedge high tibial osteotomy (OW-HTO) vs closing wedge high tibial osteotomy (CW-HTO).

METHODS

In this economic evaluation study, a cost-effectiveness analysis from the perspective of the Spanish public healthcare system was performed, comparing OW-HTO with CW-HTO. All patients with medial knee osteoarthritis who underwent one of these procedures between 2018 and 2020 in our institution were included. The cost analysis included operating room, implant, graft and hospital admission costs. Functional outcomes (KOOS-12, Tegner activity scale, pain and satisfaction) and radiological outcomes (hip-knee-ankle angle, medial proximal tibial angle, tibial slope and patellar height) were analysed. The cost-effectiveness ratio was obtained by calculating the cost of improving the minimal clinically important difference (MCID) of KOOS-12 for each procedure. All costs are expressed in 2020 euros.

RESULTS

Fifty-one patients met the inclusion criteria (27 OW-HTO and 24 CW-HTO). Good to excellent functional outcomes, significant pain reduction (>6 points) and high patient satisfaction (>9/10) were observed in both groups. Both techniques yielded excellent radiological outcomes. N.s. differences in functional or radiological outcomes improvements between both procedures were found. However, the OW-HTO group presented a higher total cost than the CW-HTO group (4612.1 ± 765.6€ vs. 1827.1 ± 701.9€; p < 0.001). The cost-effectiveness ratio was 818.1 ± 46.8 €/MCID for the CW-HTO procedure and 2414.3 ± 115.2 €/MCID for the OW-HTO procedure (p = 0.025).

CONCLUSION

The CW-HTO procedure presented a cost-effectiveness ratio almost three times lower than the OW-HTO procedure. Both techniques allowed to achieve of good to excellent functional outcomes, significant pain reduction and high patient satisfaction while correcting the varus limb malalignment and the metaphyseal tibial varus in patients with medial compartment osteoarthritis.

LEVEL OF EVIDENCE

Level III; economic study.

Predictors of first-year postoperative complications after fixation of low-energy ankle fractures: A single-center, retrospective cohort study of 663 consecutive fractures

INTRODUCTION

Rotational ankle fractures are common, have diverse personalities and affect both robust and fragile patients. Postoperative complications are frequent, creating a sizeable economic burden. The primary purpose of this study was to expand current knowledge on predictors of postoperative complications after low-energy ankle fracture fixation.

MATERIALS AND METHODS

A retrospective single-center cohort study was completed of patients undergoing internal fixation OF low-energy ankle fractures. The primary outcome was first-year postoperative complications, classified as major (surgical) or minor (non-surgical). Data on patients, their injuries, and treatments were collected. To identify potential predictors of outcomes, logistic regression methods were used, with a backward-stepwise method used for model fitting.

RESULTS

In total, 663 patients of median age 59 years were analyzed. We found a high rate of complications (28.4%), with wound-healing issues and infections predominant. Overall, 14.8% had minor complications, while 13.6% required an unplanned reoperation. On multivariable analysis, the most consistent predictors of complications were older age (OR=1.02 per year), longer operating time (3.32 per hour), and smoking (2.91).

CONCLUSIONS

Older patients and smokers who sustain fractures requiring more complex surgery are at higher risk of postoperative complications.

Sequential repeated tibial tubercle osteotomy in a two-stage exchange strategy: a superior approach to treating a chronically infected knee arthroplasty?

PURPOSE

Surgical approach can impact the reliability of the debridement after a chronic total knee periprosthetic joint infection (PJI), a factor of utmost importance to eradicate the infection. The most adequate knee surgical approach in cases of PJI is a matter of debate. The purpose of this study was to determine the influence of performing a tibial tubercle osteotomy (TTO) in a two-stage exchange protocol for knee PJI treatment.

METHODS

Retrospective cohort study examining patients managed with two-stage arthroplasty due to chronic knee PJI (2010-2019). Performance and timing of the TTO were collected. Primary end-point was infection control with a minimum FU of 12 months and according to internationally accepted criteria. Correlation between TTO timing and reinfection rate was reviewed.

RESULTS

Fifty-two cases were finally included. Overall success (average follow-up: 46.2 months) was 90.4%. Treatment success was significantly higher among cases addressed using TTO during the second stage (97.1% vs. 76.5%, p value 0.03). Only 4.8% of the patients relapsed after performing a sequential repeated TTO, that is, during both first and second stages, compared to 23.1% cases in which TTO was not done (p value 0.28). No complications were observed among patients in the TTO group with a significant decrease in soft tissue necrosis (p: 0.052).

CONCLUSION

Sequential repeated tibial tubercle osteotomy during a two-stage strategy is a reasonable option and offers high rates of infection control in complex cases of knee PJI with a low rate of complications.

Single-injection nerve blocks for total knee arthroplasty: femoral nerve block versus femoral triangle block versus adductor canal block-a randomized controlled double-blinded trial

INTRODUCTION

Femoral nerve block (FNB) is a well-established analgesic technique for TKA. However, it associates quadriceps weakness. Therefore, femoral triangle block (FTB) and adductor canal block (ACB) were proposed as effective alternative motor-spearing techniques. The primary objective was to compare quadriceps muscle strength preservation between FNB, FTB and ACB in TKA. The secondary objective was to analyze pain control and functional outcomes.

METHODS

This is a prospective, double-blinded RCT. From April 2018 to April 2019, patients who undergo a primary TKA were randomized into three experimental groups: FNB-G1/FTB-G2/ACB-G3. Quadriceps strength preservation was measured as the difference in maximum voluntary isometric contraction (MVIC) preoperatively and postoperatively.

RESULTS

Seventy-eight patients (G1, n = 22; G2, n = 26; G3, n = 30) met our inclusion/exclusion criteria. Patients with FNB retained significantly lower baseline MVIC at 6 h postoperatively (p = 0.001), but there were no differences at 24 and 48 h. There were no differences between the groups in functional outcomes at any time point. Patients in the FNB-G1 presented significant lower pain scores at 6 h (p = 0.01), 24 h (p = 0.005) and 48 h (p = 0.01). The highest cumulative opioid requirement was reported in ACB-G3.

CONCLUSION

For patients undergoing TKA, FTB and ACB preserve quadriceps strength better than FNB at 6 h postoperatively, but there are no differences at 24 and 48 h. Moreover, this early inferiority does not translate to worse functional outcomes at any time point. FNB is associated with better pain control at 6, 24 and 48 h after surgery, while ACB presents the highest cumulative opioid requirement.

CLINICAL TRIAL REGISTRATION

This study was registered in clinicaltrials.gov (NCT03518450; https://clinicaltrials.gov/ct2/show/NCT03518450 ; submitted March 17, 2018).

Closing Wedge High Tibial Osteotomy: An Old-Fashioned Technique? Survival, Clinical and Radiological Outcomes of a Case Series Analysis

INTRODUCTION

Closing wedge high tibial osteotomy (CW-HTO) is a surgical option for active patients with medial knee pain and mild-moderate osteoarthritis with varus limb deformity. Despite its good reported results, this technique has been losing popularity. The aim of this study was to analyse the survival rate, clinical functional outcomes and radiological results of CW-HTO.

METHODS

It is a retrospective case series study. Seventy patients with primary knee osteoarthritis, operated on between 2010 and 2020 in a single Spanish tertiary hospital using the CW-HTO technique and with a minimum follow-up of 2 years were analysed.

RESULTS

Survival rate was 87.6% and 75.5% after a follow-up of 5 and 10 years respectively. Functional outcomes were good-to-excellent (KSS 77.7/100 and OKS 35.6/48) and good pain control (VAS 3.9/10) and high satisfaction (7.2/10) were achieved. Limb varus malalignment was significantly corrected (mean postoperative HKA angle 177.6° and MPTA 90.7°). However, 30% of patients presented hypocorrection, which was associated with inferior survival, functionality and satisfaction.

CONCLUSION

CW-HTO technique can be useful for patients with knee osteoarthritis and varus limb. It allows to correct varus malalignment while achieving good-to-excellent functional outcomes, good pain control, high patient satisfaction and acceptable medium-long term survival rate. However, it is associated with a non-negligible risk of hypocorrection or medial hinge disruption.

Preliminary Outcomes of a Staged Percutaneous Retrograde Prefabricated Gentamicin-coated Intramedullary Nail to Manage Complications after Ankle Fusion through Tibial Bone Transport

Aim

Distal tibial injuries combining bone loss, articular destruction and infection can be treated through distraction osteogenesis combined with ankle fusion. Bone transport is not without complications. This study investigates our preliminary results using a retrograde prefabricated gentamicin-coated nail (ETN PROtect®) to treat complications after infected bone defects of the distal tibial were managed by ankle arthrodesis and distraction osteogenesis.

Materials and methods

This is a retrospective case series study. All consecutive patients with bone transport complications after ankle arthrodesis and distraction osteogenesis who were subsequently operated on using a retrograde ETN PROtect® nail were analysed. The cases occurred between 2017 and 2020. The primary objective was to report on the resolution of the clinical problem and the risk of deep infection after nail implantation.

Results

Five patients have included: two docking site non-unions, two regenerated bone fractures and one hypotrophic regenerated bone. These complications were resolved in all patients (5/5, 100%). A painless, stable and plantigrade ankle arthrodesis was achieved in all cases. No patient developed a local infection or required nail removal (mean follow-up: 35.2 months). The mean LEFS score was 46.8 ± 13.8 and the mean knee ROM was 112 ± 12.7°. All patients tolerated full weight-bearing. All patients were very satisfied with the procedure (mean SAPS score was 93.8 points).

Conclusion

The staged retrograde nailing technique using the ETN PROtect® nail may represent an effective and safe treatment for bone transport complications in high-infection-risk patients. Furthermore, the technique allows simultaneous achievement of ankle arthrodesis. The patients had good functional outcomes and were satisfied with the procedure.

Clinical significance

This strategy of using retrograde gentamicin-coated tibial nails offers a solution to resolve bone transport complications while simultaneously achieving functional ankle arthrodesis.

How to cite this article

Pujol O, Vicente M, Castellanos S, et al. Preliminary Outcomes of a Staged Percutaneous Retrograde Prefabricated Gentamicin-coated Intramedullary Nail to Manage Complications after Ankle Fusion through Tibial Bone Transport. Strategies Trauma Limb Reconstr 2023;18(3):155-162.

First surgical experience treating scoliosis using HGT and ECMO: a case report

CASE PRESENTATION

A 13-year-old female with congenital diaphragmatic hernia-associated pulmonary hypertension presented with severe and rapidly progressing scoliosis. The patient suffered from chronic respiratory failure and high risk of hypertensive crisis with potentially life-threating consequences. The scoliosis was treated with a multidisciplinary approach combining preoperative halo-gravity traction, venoarterial extracorporeal membrane oxygenation support and posterior spinal instrumented fusion. After 2 years of follow-up, results are excellent.

CONCLUSIONS

The treatment combination reported here for the first time aims to limit surgical aggressiveness. It could be an effective and safe approach for treating severe spinal deformities in very fragile patients with high surgical risk.

Atraumatic Fracture of the Femoral Component of a Cemented Total Knee Arthroplasty: A Case Report

CASE

An 81-year-old man presented with severe atraumatic knee pain. Sixteen years before, he had undergone a primary cemented total knee arthroplasty (TKA). A radiological study showed osteolysis and loosening of the femoral component. Intraoperatively, a medial femoral condyle fracture was found. A rotating-hinge revision TKA with cemented stems was implanted.

CONCLUSION

Femoral component fracture is extremely rare. Surgeons should remain vigilant with younger and heavier patients with severe unexplained pain. Early revision TKA using cemented, stemmed, and more constrained implants is usually necessary. Full and stable metal-to-bone contact through perfect cuts and a careful cementing technique avoiding debonded areas are recommended to prevent this complication.

Preoperative mechanical axis has no influence on reoperation rate in primary rotating-hinge knee arthroplasty

Background

The purpose of the study is to evaluate reoperation rate and its relationship to preoperative mechanical axis of rotating-hinge TKA used as the primary implant in complex knees.

Methods

Patients subjected to primary TKA with a rotating-hinge knee prosthesis due to primary osteoarthritis between 2010 and 2019 were retrospectively reviewed. Preoperative mechanical axis was measured using the last preoperative telemetry x-ray image. Preoperative axis was classified according to the type of deformity (varus or valgus) and its magnitude (0-15°, 16-25° or >25°). Reoperation rate (with or without implant removal) was the primary outcome of the current study. We studied if the preoperative mechanical axis (either varus-valgus, or magnitude of malalignment) was related to implant survival rate.

Results

Forty-two patients were included in the study. Mean follow-up was 51.42 ± 31.88 months. The 83.3% of patients presented a valgus axis while the 16.7% presented a varus axis. Need of reoperation occurred in eight patients (19.0%). However, no patients (0%) required implant removal with revision TKA. No association was seen between the preoperative mechanical axis and risk of reoperation (p = 0.16).

Conclusion

In selected situations that do not permit less constrained implants, primary rotating-hinge arthroplasty could be a good alternative. Risk of reoperation does not seem to depend upon the preoperative mechanical axis when using a rotating-hinge knee prosthesis for primary arthroplasty in non-tumoral complex knees.

Iliopsoas impingement after total hip arthroplasty: Does the CT-scan have any role? Our Algorithm proposal

Introduction

The first surgical option considered in managing iliopsoas impingement following THA is endoscopic/arthroscopic iliopsoas tenotomy, because of its low risk and minimal invasiveness. Acetabular revision is a much more aggressive surgery, recommended only in cases of substantial cup malposition. However, there are no clear indications for this procedure. The purpose of this article is to analyse the role of CT-scan measurement of acetabular cup positioning in a therapeutic algorithm for iliopsoas impingement.

Methods

In this retrospective observational study, we reviewed 25 patients treated for iliopsoas impingement following THA between 2011 and 2019. We studied acetabular cup positioning using CT-scan. We compared radiological parameters of patients who presented with significant clinical improvement with conservative treatment and with tenotomy against those who did not. Finally, we developed a proposed therapeutic algorithm.

Results

Forty-eight percent of patients presented a significant clinical improvement following conservative treatment. Patients who did not improve were found to have greater acetabular cup axial and sagittal overhang (p-values 0.016 and 0.003). These patients were considered for tenotomy. Of this group, those who did not improve with surgery (38%) showed greater axial overhang (p-value 0.005).

Conclusions

Conservative management should be the first line of treatment. In cases of non-operative treatment failure, axial acetabular cup overhang measured by CT-scan can be a useful tool in choosing between iliopsoas tenotomy or cup-revision surgery in selected cases of very severe acetabular malposition. A cut-off point of 10 mm of axial overhang is a reliable predictor of higher failure risk with iliopsoas tenotomy.

Outcomes of two circular external fixation systems in the definitive treatment of acute tibial fracture related infections

INTRODUCTION

Acute tibial fracture-related infection (FRI) is one of the most feared and challenging complications after a tibial fracture. The most appropriate treatment in this scenario is far from a resolved topic. Circular external fixators (CEFs) offer multiplanar control and minimize soft tissue injury using temporary implants far from the infected area. This study aimed to investigate the outcomes of two different types of CEFs (Ilizarov and hexapod) in the treatment of a series of acute tibial FRIs.

MATERIAL AND METHODS

A retrospective study at two specialized limb reconstruction centres identified all patients with an acute tibial FRI (≤4 weeks after index procedure) definitively treated with a CEF from January 2015 to December 2020.

PRIMARY OUTCOMES

fracture healing and infection eradication rate with a minimum FU of 12 months after frame removal.

SECONDARY OUTCOMES

to investigate the differences between the two types of circular frames regarding final post-treatment deformity magnitude.

RESULTS

We included 31 patients with acute tibial FRIs: 18 treated with hexapod-type and 13 with Ilizarov-type CEFs. Average age was 45.5±16.56 years. Fracture healing and infection eradication were achieved in all patients (31/31) after a mean follow-up of 24.7 months (range 12.1-55.3). Patients treated with an Ilizarov-type fixator presented shorter time to fracture union (5.5±2.2 months vs. 9.2±6.0 months; p-value 0.021) and shorter duration of external fixation (p-value 0.001). Regarding residual post-treatment deformity, the hexapod system presented significantly less residual coronal translation deformity (p-value 0.034) and better callus quality. Fixator-related complications were similar when comparing the two groups. No significant differences were seen in pain (p-value 0.25), RTW rate (35% vs. 45%; p-value 0.7) or functionality (p-value 0.4).

CONCLUSIONS

Definitive circular external fixation is an excellent treatment for acute tibial FRI. Both Ilizarov and hexapod systems offer a very high rate of fracture healing and infection eradication. Although both presented very low radiological post-operative residual deformity, the hexapod system showed less residual coronal translation deformity and better callus quality.

Over-The-Top Technique for Revision ACL Reconstruction with Achilles Allograft and Associated Lateral Extra-articular Tenodesis

Revision anterior cruciate ligament reconstruction (ACL-R) is made challenging by the frequent presence of rotatory instability, tunnel malpositioning and widening, and limited autograft options. Lateral extra-articular tenodesis (LET), alternative tunnel routing, and the use of allograft tissue can be used to manage these challenges. This Technical Note describes revision ACL-R using the over-the-top (OTT) technique with Achilles tendon allograft with concomitant LET. The surgical approach involves routing the graft around the posterior aspect of the lateral femoral condyle, and then deep to the iliotibial band to a site just medial to Gerdy's tubercle, with staple fixation on the lateral femur for the ACL-R and anterolateral tibia for the LET. The OTT technique with LET provides a versatile approach for the management of failed ACL-R by circumventing challenges in revision ACL-R and addressing rotatory instability, a contributing factor to prior graft failure.

Should we employ preoperative templating in hip hemiarthroplasty after femoral neck fracture? A nested case-control study

INTRODUCTION

Dislocation following hip hemiarthroplasty is a serious complication. It remains unclear if acetabular morphology is associated with a higher risk of dislocation. The aim of our study was to investigate whether there are differences in hip morphology radiological parameters between patients who have suffered a dislocation episode, and those who have not suffered a dislocation.

MATERIAL AND METHODS

Between January 2015 and December 2018, a nested case-control study was performed. From 707 patients who underwent hip hemiarthroplasty because of femoral neck fracture, 50 patients (50 hips) suffered an episode of dislocation. They were randomly matched with 94 patients (100 hips) without dislocation (ratio 1:2). Clinical data regarding demographics, medical comorbidities and surgical and radiological parameters were studied.

RESULTS

Statistically significantly smaller lateral centre-edge angle (LCEA) and femoral offset (FO) and greater Tönnis angle were found in the dislocation group. No differences in acetabular angle were seen. Neurological impairment prevalence was statistically significantly higher in patients who suffered a dislocation (60% vs. 44%, p = 0.011).

CONCLUSIONS

The current study suggests that a smaller LCEA and FO, a greater TA, and neurological impairment could be related to a higher risk of hip hemiarthroplasty dislocation after femoral neck fracture in the elderly. We consider that preoperative templating could be helpful in identifying abnormal parameters and carefully planning surgery could lead to changes in treatment strategy, such as choosing a dual-mobility total hip arthroplasty.

Considerations of the Posterior Tibial Slope in Anterior Cruciate Ligament Reconstruction: a Scoping Review

PURPOSE OF REVIEW

The significance of posterior tibial slope (PTS) in the setting of anterior cruciate ligament (ACL) injury and reconstruction has been increasingly recognized in recent years. The purpose of this article is to review the biomechanical and clinical studies of PTS in conjunction with ACL injuries, providing an evidence-based approach for the evaluation and management of this patient population.

RECENT FINDINGS

Several biomechanical and clinical studies suggest that PTS > 12° may be considered with increased strain on the native ACL fibers (or reconstructed graft) and greater anterior tibial translation, predisposing patients to a recurrent ACL injury. The increased rates of ACL injury and graft failure seen in those with increased PTS have garnered attention to diagnose and surgically address increased PTS in the revision ACL setting; however, the role of a slope-reducing high tibial osteotomy (HTO) in primary ACL reconstruction (ACL-R) has yet to be defined. Various HTO techniques to decrease PTS during revision ACL-R have demonstrated promising outcomes, though conclusions are limited by the multifactorial nature of revision surgery and concomitant procedures performed. Recent evidence suggests that increased PTS is a risk factor for failure following ACL-R, which may be mitigated by a slope-reducing HTO. Further investigation is needed to elucidate abnormal PTS values and to determine appropriate indications for a slope-reducing HTO in primary ACL-R.

Machine Learning-Based Surrogate Model for Press Hardening Process of 22MnB5 Sheet Steel Simulation in Industry 4.0

The digitalization of manufacturing processes offers great potential in quality control, traceability, and the planning and setup of production. In this regard, process simulation is a well-known technology and a key step in the design of manufacturing processes. However, process simulations are computationally and time-expensive, typically beyond the manufacturing-cycle time, severely limiting their usefulness in real-time process control. Machine Learning-based surrogate models can overcome these drawbacks, and offer the possibility to achieve a soft real-time response, which can be potentially developed into full close-loop manufacturing systems, at a computational cost that can be realistically implemented in an industrial setting. This paper explores the novel concept of using a surrogate model to analyze the case of the press hardening of a steel sheet of 22MnB5. This hot sheet metal forming process involves a crucial heat treatment step, directly related to the final part quality. Given its common use in high-responsibility automobile parts, this process is an interesting candidate for digitalization in order to ensure production quality and traceability. A comparison of different data and model training strategies is presented. Finite element simulations for a transient heat transfer analysis are performed with ABAQUS software and they are used for the training data generation to effectively implement a ML-based surrogate model capable of predicting key process outputs for entire batch productions. The resulting final surrogate predicts the behavior and evolution of the most important temperature variables of the process in a wide range of scenarios, with a mean absolute error around 3 °C, but reducing the time four orders of magnitude with respect to the simulations. Moreover, the methodology presented is not only relevant for manufacturing purposes, but can be a technology enabler for advanced systems, such as digital twins and autonomous process control.

A comparative of a single novice surgeon's direct anterior approach and posterior approach learning curves in total hip arthroplasty: a retrospective cohort study

INTRODUCTION

The purpose of the present study was to compare a novice surgeon's learning curves with the direct anterior approach and posterior approach in total hip arthroplasty.

METHODS

A consecutive series of 376 total hip arthroplasties performed from November 2014 to September 2019 in a level-one healthcare center by a single surgeon (V.B) were retrospectively studied. Demographic data, functional outcomes, and complications were collected and compared.

RESULTS

Within the ranks of the patients studied, we found differences between groups with respect to dislocation rate and length of stay; these were lower in the direct anterior approach (DAA) group. The approach was not associated with an increase in complications, but rather with a decrease in the rate of dislocations and better functional outcomes at 1-year follow-up. Operative time was initially higher with this approach, but equalized during the learning curve.

CONCLUSION

The DAA can be safe even in the early stages of a novice surgeon's learning curve. It does not present a higher complication rate than the posterior approach, either in infection rate or in periprosthetic fractures. However, the DAA may provide greater functionality, lower dislocation rate and a shorter hospital stay. It can also be concluded that after having performed a certain number of interventions, operative time for the DAA can be comparable to that of other approaches.

High reoperation and mortality rate after distal femoral replacement for periprosthetic knee fracture in the elderly

PURPOSE

To analyze the outcomes of elderly patients with periprosthetic fractures around the knee operated on with a distal femur replacement (DFR).

METHODS

We performed a retrospective case series study of eleven elderly patients who underwent DFR due to a periprosthetic fracture. Mean follow-up was 30.1 months (SD 28.1). Demographic, clinical and radiological data were reviewed. A descriptive analysis and a study of survival were conducted. Then, a comparative analysis between the patients who needed reoperation and did not need reoperation, and the patients who died and the patients who were alive during the follow-up was performed.

RESULTS

Mean age was 77.1 years (SD 13.9). Reoperation rate was 36%, being infection the most common complication (27%). The risk of reoperation increased with a longer time between fracture and surgery. The 36.4% of patients died during the follow-up. Older age, need of blood transfusion and need of early reoperation were related to a higher risk of mortality.

CONCLUSION

DFR could be a valuable option for knee periprosthetic fractures in elderly patients. However, surgeons should be aware of the high reoperation and mortality rate.

Pulmonary Embolism after Core Decompression of the Femoral Head Using Injectable Bone Graft Substitute: A Case Report

The authors report a rare complication regarding the case of an 18-year-old female with bilateral osteonecrosis of the femoral head (ONFH) secondary to the treatment and hematopoietic stem cell transplant (HSCT) of an acute lymphoblastic leukemia (ALL). The patient underwent a bilateral necrotic bone debridement and core decompression (CD) surgery with injectable synthetic bone graft, which unfortunately caused a pulmonary injectable bone graft substitute embolism.

Restoring hip biomechanics during the learning curve of a novice surgeon: Direct anterior approach vs posterior approach

Introduction

It remains controversial whether the direct anterior approach (DAA) or the posterior approach (PA) allows better restoration of hip biomechanics after total hip arthroplasty (THA). Besides, it is not certain which approach is best for a novice surgeon to avoid implant malposition, neither during the learning curve nor once the curve plateau has been reached.

Methods

We performed a retrospective cohort study of THAs operated on between 2014 and 2019 by a single novice surgeon (DAA, n = 187; PA, n = 184). The surgeon used both approaches, and thus went through parallel learning curves.

Results

While the DAA presented a greater number of acetabular cup implantations within Lewinnek's "safe zone" for inclination (84.5% vs. 79.3%; p = 0.003), the PA returned superior results for anteversion (77.7% vs. 68.4%; p = 0.000). The PA showed a tendency to verticalize acetabular cups, while the DAA tended to antevert them. The DAA resulted in fewer patients with leg length discrepancy (3.2% vs. 8.2%, p = 0.041). No differences were found in stem coronal alignment or femoral offset.

Conclusion

Both approaches are safe and reliable for restoring hip biomechanics through THA surgery during the learning curve of a novice hip surgeon. Similar radiological outcomes are also seen once the surgeon has reached the learning curve plateau.

Differential Replication for Credit Scoring in Regulated Environments

Differential replication is a method to adapt existing machine learning solutions to the demands of highly regulated environments by reusing knowledge from one generation to the next. Copying is a technique that allows differential replication by projecting a given classifier onto a new hypothesis space, in circumstances where access to both the original solution and its training data is limited. The resulting model replicates the original decision behavior while displaying new features and characteristics. In this paper, we apply this approach to a use case in the context of credit scoring. We use a private residential mortgage default dataset. We show that differential replication through copying can be exploited to adapt a given solution to the changing demands of a constrained environment such as that of the financial market. In particular, we show how copying can be used to replicate the decision behavior not only of a model, but also of a full pipeline. As a result, we can ensure the decomposability of the attributes used to provide explanations for credit scoring models and reduce the time-to-market delivery of these solutions.

Simultaneous bilateral dual mobility total hip arthroplasty dislocation in a patient with hepatic encephalopathy: A case report

INTRODUCTION AND IMPORTANCE

Dislocation is a severe complication after total hip arthroplasty (THA). It is one of the most common reasons for failure and revision surgery. This is the first case of a documented simultaneous bilateral dual mobility (DM) THA dislocation.

CASE PRESENTATION

A forty-nine-year-old man presented with bilateral hip pain, immobility and deformity. X-ray images demonstrated simultaneous bilateral posterior THA dislocation. Previously, the patient had presented atraumatic dislocations recurrently. When he was thoroughly re-interrogated, he complained of uncontrolled and generalized muscle contractions, which were compatible with myoclonus due to hepatic encephalopathy (HE). Multidisciplinary treatment was performed satisfactorily to control myoclonus symptomatology and to prevent dislocation.

CLINICAL DISCUSSION

Patient's most important risk factor was a neuromuscular disorder, which we initially gave little notice and undervalued. HE is a serious but reversible syndrome, observed in patients with liver dysfunction. It leads to a wide spectrum of neuropsychiatric abnormalities. Management is based on prevention of episodes, avoiding the underlying triggers. Due to the high risk for dislocation of our patient, we decided to use DM cups bilaterally. This system has demonstrated lower rates of dislocation.

CONCLUSION

This case report reminds us that a careful evaluation through meticulous history and physical examination are mandatory when faced with recurrent instability. Furthermore, prevention of dislocation is vastly preferable to treating this challenging complication. High-risk patients should be identified, and appropriate surgical approach, technique and implants have to be collectively used to reach a strategy that mitigates and ideally prevents dislocation.

Risk mitigation in algorithmic accountability: The role of machine learning copies

Machine learning plays an increasingly important role in our society and economy and is already having an impact on our daily life in many different ways. From several perspectives, machine learning is seen as the new engine of productivity and economic growth. It can increase the business efficiency and improve any decision-making process, and of course, spawn the creation of new products and services by using complex machine learning algorithms. In this scenario, the lack of actionable accountability-related guidance is potentially the single most important challenge facing the machine learning community. Machine learning systems are often composed of many parts and ingredients, mixing third party components or software-as-a-service APIs, among others. In this paper we study the role of copies for risk mitigation in such machine learning systems. Formally, a copy can be regarded as an approximated projection operator of a model into a target model hypothesis set. Under the conceptual framework of actionable accountability, we explore the use of copies as a viable alternative in circumstances where models cannot be re-trained, nor enhanced by means of a wrapper. We use a real residential mortgage default dataset as a use case to illustrate the feasibility of this approach.

Environmental Adaptation and Differential Replication in Machine Learning

When deployed in the wild, machine learning models are usually confronted with an environment that imposes severe constraints. As this environment evolves, so do these constraints. As a result, the feasible set of solutions for the considered need is prone to change in time. We refer to this problem as that of environmental adaptation. In this paper, we formalize environmental adaptation and discuss how it differs from other problems in the literature. We propose solutions based on differential replication, a technique where the knowledge acquired by the deployed models is reused in specific ways to train more suitable future generations. We discuss different mechanisms to implement differential replications in practice, depending on the considered level of knowledge. Finally, we present seven examples where the problem of environmental adaptation can be solved through differential replication in real-life applications.

Results of a fast-track knee arthroplasty according to the experience of a multidisciplinary team

Introduction

Fast-Track is a multidisciplinary system that has changed the perception of total knee arthroplasty surgery. It's based on the education of the patient, an increased autonomy, adequate pain control and early mobilization. In the bibliography, there are no articles that refer to the evolution of the protocol once established, and most of them are comparatives with the previously existing conventional system. For this reason, the objective of our work is to study the evolution of the clinical results obtained through a Fast-Track system according to the experience acquired by the multidisciplinary team in this protocol.

Material and methods

It's a prospective observational study. We have analyzed the results obtained in our center from its implementation in 2013 (n = 65) to the end of the study in 2016 (n = 60). We evaluated the pain at 24 and 48 h after surgery, the time until the first ambulation, the range of flexion and extension at discharge, and length of hospital stay.

Results

The results obtained at the beginning of the implantation of the Fast-Track protocol in our center and the present ones do not present statistically significant differences. Mean pain at 24 h was 1,65/10 in 2013 and 1,5/10 in 2016, and at 48 h 1,61/10 and 1,58/10 respectively. Most of the patients in both years scored a pain below 4/10 at 24 h and 48 h. Mean time of the first ambulation was 260 min in 2013 and 254 min in 2016 (most of the patients started walking in ≤5 h). Mean flexion at discharge was 90,3° in 2013 and 87,92° in 2016 (most of the patients presented a flexion between 80 and 100°). Mean extension at discharge was 6,95° in 2013 and 8,1° in 2016 (most of the patients presented an extension between 0 and 10°). Mean length of stay was 2,46 days in 2013 and 2,43 days in 2016 (most of the patients had a stay of fewer than 4 days).

Conclusions

When applying the Fast-Track protocol by a multidisciplinary team in primary knee prosthetic surgery, the clinical results obtained are independent of the experience of this team in the protocol. So, from our experience, we can affirm that the protocol has enough solidity since its beginning and it maintains similar results despite the years of execution.

Error-Correcting Factorization

Error Correcting Output Codes (ECOC) is a successful technique in multi-class classification, which is a core problem in Pattern Recognition and Machine Learning. A major advantage of ECOC over other methods is that the multi-class problem is decoupled into a set of binary problems that are solved independently. However, literature defines a general error-correcting capability for ECOCs without analyzing how it distributes among classes, hindering a deeper analysis of pair-wise error-correction. To address these limitations this paper proposes an Error-Correcting Factorization (ECF) method. Our contribution is three fold: (I) We propose a novel representation of the error-correction capability, called the design matrix, that enables us to build an ECOC on the basis of allocating correction to pairs of classes. (II) We derive the optimal code length of an ECOC using rank properties of the design matrix. (III) ECF is formulated as a discrete optimization problem, and a relaxed solution is found using an efficient constrained block coordinate descent approach. (IV) Enabled by the flexibility introduced with the design matrix we propose to allocate the error-correction on classes that are prone to confusion. Experimental results in several databases show that when allocating the error-correction to confusable classes ECF outperforms state-of-the-art approaches.

Retinal Pigment Epithelial Tears after Intravitreal Bevacizumab Injection for Predominantly Classic Choroidal Neovascularization

Purpose

To detect retinal pigment epithelium (RPE) tears in predominantly classic choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD) treated with intravitreal bevacizumab injections.

Methods

Forty consecutive patients with predominantly classic CNV secondary to AMD were treated with 1.25 mg of intravitreal bevacizumab. Patients were evaluated with visual acuity (VA) measured with Early Treatment Diabetic Retinopathy Study charts, optical coherence tomography, and fluorescein angiography.

Results

Three patients developed a RPE tear after the first injection. The first patient had been treated with verteporfin therapy and VA remained unchanged. In the other two cases the CNV was naïve and VA improved since the foveal center was not involved by the tear and macular edema was reduced.

Conclusions

RPE tears can occur following intravitreal bevacizumab injections in patients with predominantly classic CNV although VA is not always affected.

A Gesture Recognition System for Detecting Behavioral Patterns of ADHD

We present an application of gesture recognition using an extension of dynamic time warping (DTW) to recognize behavioral patterns of attention deficit hyperactivity disorder (ADHD). We propose an extension of DTW using one-class classifiers in order to be able to encode the variability of a gesture category, and thus, perform an alignment between a gesture sample and a gesture class. We model the set of gesture samples of a certain gesture category using either Gaussian mixture models or an approximation of convex hulls. Thus, we add a theoretical contribution to classical warping path in DTW by including local modeling of intraclass gesture variability. This methodology is applied in a clinical context, detecting a group of ADHD behavioral patterns defined by experts in psychology/psychiatry, to provide support to clinicians in the diagnose procedure. The proposed methodology is tested on a novel multimodal dataset (RGB plus depth) of ADHD children recordings with behavioral patterns. We obtain satisfying results when compared to standard state-of-the-art approaches in the DTW context.