Role of Different Fuels and Sintering Temperatures in the Structural, Optical, Magnetic, and Photocatalytic Properties of Chromium-Containing Nickel Ferrite: Kinetic Study of Photocatalytic Degradation of Rhodamine B Dye.

In the present paper, nanocrystalline samples of NiCrFeO4 were synthesized by the combustion method using different fuels such as glycine, urea, and poly(vinyl alcohol) and subjected to heat treatment at different temperatures of 600, 700, 800, and 1000 °C for 6 h. The formation of phases with highly crystalline structures was confirmed by XRD and Rietveld refinement analysis. The optical band gap of NiCrFeO4 ferrites lies in the visible range, making them suitable photocatalysts. BET analysis reveals that the surface area of the phase synthesized using PVA is much higher than that synthesized using other fuels at each sintering temperature. In addition, there is a significant decrease in the surface area with sintering temperature for the catalysts prepared using the fuels PVA and urea, while it almost remains constant in the case of glycine. Magnetic studies demonstrate the dependence of saturation magnetization on the nature of the fuel and on the sintering temperature; moreover, the coercivity and squareness ratio confirm the single domain nature of all the synthesized phases. We have also performed photocatalytic degradation of the highly toxic Rhodamine B (RhB) dye by employing all the prepared phases as photocatalysts using the mild oxidant H2O2. It is observed that the photocatalyst prepared using PVA as the fuel exhibited the best photocatalytic activity at all sintering temperatures. All the three photocatalysts prepared using different fuels showed a decrease in the photocatalytic activity with increasing sintering temperature. From the chemical kinetic point of view, the degradation of RhB by all the photocatalysts was found to follow pseudo-first-order kinetics.

Solvent-Free Combustion-Assisted Synthesis of LaFe0.5Cr0.5O3 Nanostructures for Excellent Photocatalytic Performance toward Water Decontamination: The Effect of Fuel on Structural, Magnetic, and Photocatalytic Properties.

The present study reports the synthesis of nanocrystalline LaFe0.5Cr0.5O3 via a solvent-free combustion method using glycine, poly(vinyl alcohol), and urea as fuels, with superior photocatalytic activity. Rietveld refinement and powder X-ray diffraction data of nanomaterials demonstrate the existence of an orthorhombic phase that corresponds to the Pbnm space group. The crystallite size of nanoperovskite samples lies in the range of 20.9-36.4 nm. The Brunauer-Emmett-Teller (BET) surface area of the LaFe0.5Cr0.5O3 fabricated using urea is found to be higher than that of the samples prepared using other fuels. The magnetic measurements of all samples done using a SQUID magnetometer showed a dominant antiferromagnetic character along with some weak ferromagnetic interactions. The optical band gap of all nanosamples lies in the visible range (2-2.6 eV), making them suitable photocatalysts in visible light. Their use as a photocatalyst for the degradation of the rhodamine B dye (model pollutant) is studied, and it has been observed that the catalyst fabricated using urea shows excellent degradation efficiency for rhodamine B, i.e., 99% in 60 min, with high reusability up to five runs. Additionally, the degradation of other organic dyes such as methylene blue, methyl orange, and a mixture of these dyes (rhodamine B + methylene blue + methyl orange) is also investigated with the most active photocatalyst, i.e., LFCO-U, to check its versatility.

New Rare Earth-Doped Bilayered Perovskite Oxide Photocatalysts Sr2La0.5R0.5FeMnO7 (R = La, Nd, Sm, Gd, Dy) for the Degradation of Highly Toxic Methylene Blue Dye in Wastewater under Visible Light: Structural, Optical, and Magnetic Properties.

This paper presents the rare earth doping effect on the structural, optical, and magnetic properties of bilayered Ruddlesden-Popper oxides Sr2La0.5R0.5FeMnO7 (R = La, Nd, Sm, Gd, Dy). Moreover, we are reporting for the first time a new rare earth-doped bilayered perovskite oxide series for the highly toxic methylene blue dye degradation in wastewater under visible light. Structural analysis of the PXRD data using the Rietveld refinements confirms the formation of the phases in tetragonal symmetry with the I4/mmm space group. The unit cell lattice parameters (a & c) and the cell volume (V) decrease monotonically from La- to Dy-doped samples owing to the decrease in the lanthanide ionic radii. The X-ray photoelectron spectroscopy analysis indicates the existence of the Mn ions in the mixed valence state. The DRS study shows that the energy band gap value decreases on moving from La to Gd substitution; however, it further increases for the Dy-doped sample. The magnetic measurements reveal that all the phases exhibit dominant anti-ferromagnetic interactions with Neel temperature (T N) observed at 150, 147, 138, 113, and 117 K for La-, Nd-, Sm-, Gd-, and Dy-substituted phases, respectively. However, the presence of an unsaturated hysteresis loop observed in the isothermal magnetic field (H) vs magnetization (M) plot also indicates the existence of weak ferromagnetic interactions. The investigation of the photocatalytic activity of the synthesized samples was done by carrying out photo-oxidative degradation of methylene blue (MB) dye pollutants. The results show that the photodegradation enhances by doping with heavier rare earth ions with the exception of the Dy-doped sample. The Gd-doped catalyst shows the maximum degradation efficiency of 99.03% in 50 min under visible light irradiation. The scavenging experiments confirmed that the·OH was the main/dominant oxidizing agent involved in the degradation of the MB dye.

Different Fuel-Adopted Combustion Syntheses of Nano-Structured NiCrFeO4: A Highly Recyclable and Versatile Catalyst for Reduction of Nitroarenes at Room Temperature and Photocatalytic Degradation of Various Organic Dyes in Unitary and Ternary Solutions.

As industrialization progresses, there is a large release of hazardous pollutants into the environment. These pollutants, which contain nitro compounds and organic dyes, are extremely dangerous due to their toxic and carcinogenic nature. An efficient, environmentally benign, and economical catalyst to degrade environmental pollutants or convert them into useful products has been of sustained interest in recent years. In this context, we report a simple and inexpensive combustion fabrication of NiCrFeO4 using different fuels such as glycine, polyvinyl alcohol (PVA), and urea, showing tremendous catalytic and photocatalytic functionalities. Rietveld refinement and X-ray diffraction studies confirmed the formation of single-phase ferrites, with crystallite sizes ranging from 3.9 to 43.31 nm. The values of optical band gap, obtained from the diffused reflectance spectroscopy technique, lie in the visible region range (1.50-1.60 eV), and hence, all the synthesized ferrites can act as good photocatalysts in the presence of visible light. All the NCF nanocatalysts were utilized for the reduction of nitroarenes and photocatalytic degradation of various cationic (RhB and MB) and anionic (MO) dyes and their mixture. NCFP displayed excellent activity for the reduction and oxidation reactions owing to its large surface area and low optical band gap. Furthermore, the photo-oxidative degradation by NCFP was also enhanced due to its low recombination of charge carriers as confirmed by the photoluminescence (PL) spectroscopy. NCFP efficiently reduces nitrobenzene to aminobenzene with 95% yield using sodium borohydride as the reducing agent in methanol medium at RT in 10 min. The results of photocatalytic activity have shown that the degradation efficiency of NCFP follows the order RhB > MB > MO in their unitary solution. Furthermore, in the case of the mixture of dyes, NCFP showed enhanced photocatalytic degradation for cationic dyes (RhB and MB) compared to that of anionic dye (MO). From the performance point of view, this catalyst can be useful in industrial application because of its high stability, greater catalytic efficiency, and cost-effectiveness.

Outcomes of Dynamic Condylar Screw Fixation for Unstable Peritrochanteric Fractures.

Background The optimal treatment modality and choice of implant for unstable peritrochanteric fractures is debatable, with multiple options ranging from intramedullary to extramedullary implants. The purpose of this study was to evaluate the radiological and functional outcomes of 95° dynamic condylar screws in unstable intertrochanteric fractures. Patients and methods This is a retrospective review of patients with unstable peritrochanteric fractures (31-A2 and A3 for Association for Osteosynthesis/Association for the Study of Internal Fixation (AO/ASIF) classification) who underwent open reduction and internal fixation with 95° dynamic condylar screw at Recep Tayyip Erdogan Hospital between 2014 and 2018. All the patients had a minimum of one year of follow-up. Clinical outcomes were measured in terms of time to full weight bearing, Harris Hip Score, and time to radiographic union. Results This study comprised 84 patients (including 56 males and 28 females with a mean age of 57.2 ± 9.7 years). The average time to full weight bearing was 4.2 months (range: three to six months). The radiological union was seen at a mean of 5.8 months (range: 4-11 months). Functional outcome in terms of Harris Hip Score was graded as excellent, good, fair, and poor in 18, 45, 16, and five patients, respectively. Implant failure was observed in three patients. One patient sustained a peri-prosthetic fracture, which was treated with a longer plate. Conclusion Dynamic condylar screw proves to be a reliable implant when used in unstable peritrochanteric fractures and results in satisfactory functional and radiological outcomes.

Comparison of functional outcome of simultaneous and staged bilateral total knee arthroplasty : systematic review of literature.

Safety of simultaneous bilateral TKA (simBTKA) and staged BTKA (staBTKA) have been compared in previous systematic reviews but functional outcome remains neglected aspect of the debate. We performed a systematic review of contemporary literature to compare the functional outcome of simBTKA and staBTKA. We searched PubMed/MEDLINE, EMBASE and Cochrane Central Database to identify all articles published between 2000 and July 2020 that evaluated the outcome of patients undergoing BTKA either in simultaneous or staged manner. Ten articles were identified which met the inclusion criteria. Functional outcome was reported in terms of Knee Society score (KSS), range of motion (ROM), Oxford Knee Score (OKS) and Western Ontario and McMaster University score (WOMAC) in seven, five, four and two studies respectively. KSS gained on average 66.6 points (47.5-95.3) for simBTKA and 65.1 points (44.4-97.2) for staBTKA without significant difference between two groups. There was no difference in post-operative ROM (maximum post-operative flexion being 124.4 and 125.1 for simBTKA and staBTKA groups respectively). Mean improvement in OKS ranged from 20 to 32.6 for simBTKA and 21.6 to 33.1 for staBTKA. There was moderate evidence to suggest that both simultaneous BTKA and staged BTKA produce equivalent improvement in functional scores.

Outcomes of Direct Infrapectineal Buttress Plate for Quadrilateral Surface Fractures of Acetabulum Using an Anterior Intrapelvic Approach.

PURPOSE: Reduction and stable fixation of the quadrilateral plate are challenging primarily due to its location in the true pelvis, limited bone stock, juxta-articular nature, and its comminution. The current study aimed to investigate the quality of reduction and functional outcomes after open reduction and internal fixation (ORIF) with infrapectineal buttress plating of the quadrilateral surface via an anterior intrapelvic approach. MATERIALS AND METHODS: We conducted a retrospective review of twenty-one patients with acetabular fractures involving quadrilateral plate operated at Ghurki Trust Teaching Hospital between January 2017 and December 2018. Radiological assessment of the quality of reduction was conducted using criteria described by Matta. Functional outcomes were evaluated using a modified Postel Merle d'Aubigné score. RESULTS: The current study included 15 males and 6 females with a mean age of 40.67±12.17 years (range, 22-62 years). The most common fracture pattern was anterior column and posterior hemi-transverse in eight patients followed by true bicolumn and T-type fractures in seven and four patients respectively. Both transverse fractures were transtectal. The quality of reduction according to Matta criteria was anatomical in 14 patients, imperfect in five and poor in two. Functional outcomes were excellent in 47.6% cases, good in 42.9%, and fair in 9.5% cases. Both patients with fair outcomes had non-anatomical reduction, and one required total hip arthroplasty at a later time. CONCLUSION: Quadrilateral plate reconstruction with an infrapectineal buttress plate applied though an anterior intrapelvic approach provides high rates of anatomical reduction and yields good functional outcomes.

Permanent pacemaker implantation associated tricuspid regurgitation.

OBJECTIVE: To determine the prevalence of tricuspid regurgitation in patients with dual-chamber permanent pacemaker implantation. METHODS: This study included 153 patients undergoing permanent pacemaker implantation. All eligible candidates had baseline transthoracic echocardiography to rule out preexisting tricuspid regurgitation. Echocardiography across the tricuspid valve was repeated one month after permanent pacemaker implantation, and the frequency of significant tricuspid regurgitation was determined. The associations of potential effect modifiers (age, sex, height, body mass index categories, diabetes, and hypertension) with tricuspid regurgitation were assessed individually using simple and multivariable logistic regression models. RESULTS: After dual-chamber permanent pacemaker implantation, significant tricuspid regurgitation was present in 22 (15.8%) patients. Tricuspid regurgitation was significantly associated with body mass index >30 kg·m-2 (odds ratio = 32.84, 95% confidence interval: 1.26-853.82, p = 0.04). CONCLUSION: Significant tricuspid regurgitation was present in substantial number of patients after dual-chamber pacemaker implantation and was independently associated with body mass index >30 kg·m-2.

Timing of Surgery in Thoracolumbar Spine Injury: Impact on Neurological Outcome.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: We aimed to evaluate the improvement in neurological deficit following early versus late decompression and stabilization of thoracolumbar junctional fractures. METHODS: This is a retrospective evaluation of all patients with a traumatic spinal cord injury (SCI) from T11 to L2 treated at a teaching hospital between 2010 and 2017. Grouped analysis was performed comparing the cohort of patients who received early surgery within 24 hours (group 1) with those operated within 24 to 72 hours (group 2) and more than 72 hours after SCI (group 3). The primary outcome was the change in ASIA (American Spinal Injury Association) motor score at 12-month follow-up. RESULTS: There were 317 patients (225 males and 92 females with mean age of 31.55 ± 12.43 years). A total of 144, 77, and 96 patients belonged to groups 1, 2, and 3 respectively. Improvement of at least 1 grade on ASIA classification was observed in 80, 45, and 33 patients in groups 1, 2, and 3 respectively (P = .001). Overall, 32, 12, and 10 patients improved ≥2 grades on ASIA classification in groups 1, 2, and 3, respectively (P = .069). On logistic regression analysis, early surgery and severity of initial injury (complete [ASIA A] vs incomplete SCI [ASIA B-D]) were found to significantly influence the potential for neurologic improvement (P = .004 and P < .0001, respectively). CONCLUSION: We believe that the earlier the decompression, the better. The 72-hour cutoff represents the most promising time window during which surgical decompression has the potential to confer a neuroprotective effect in the setting of incomplete SCI (ASIA B-D) in the distal region of the spinal cord (conus medullaris).

Impact of metal density on deformity correction in posterior fusions for adolescent idiopathic scoliosis: A retrospective cohort study.

INTRODUCTION: Optimal implant density for posterior spinal fusion in adolescent idiopathic scoliosis (AIS) remains controversial. We aimed to examine radiographic outcomes of AIS cases treated with limited density pedicle screw constructs. METHODS: This is a retrospective analysis of 96 patients (89 females and 7 males with mean age of 13.8 ± 4.4 years) with AIS who underwent posterior spinal instrumentation at Ghurki Trust Teaching Hospital between 2014 and 2016. Construct characteristics and radiographic measurements were compared preoperatively and at 2 year follow-up using paired t-test. Pearson's correlation coefficient between curve characteristics and metal density was calculated. RESULTS: Preoperative coronal Cobb angle was 68.5 ± 6.9°. Flexibility of the curve was 47.5 ± 10.3% based on push-prone films. The mean number of vertebrae in the fusion was 10.7 ± 1.6. The implant density was 62%. The mean postoperative Cobb angle was 18.6 ± 4.2°, giving a mean correction of 72.5 ± 6.8%. Metal density was not correlated with preoperative coronal or sagittal radiographic variables; MT Cobb angle (r = 0.02, p = 0.847), MT curve flexibility (r = 0.129, p = 0.210), preoperative thoracic kyphosis (r = -0.119, p = 0.247) or lumbosacral lordosis (r = -0.048, p = 0.645). There was a significant correlation between the flexibility of the curve as assessed by push-prone radiographs with the percentage correction achieved (r = 0.368, p < 0.0001) as well as absolute correction in degrees (r = 0.643, p < 0.0001). No significant correlations were present between metal density and MT curve coronal correction rate/percentage (r = 0.086, p = 0.407) or postoperative Cobb angle (r = 0.098, p = 0.344). CONCLUSION: Metal density does not influence the coronal and sagittal correction of AIS. Neither larger nor stiffer curves necessitate high metal density. LEVEL OF EVIDENCE: IV.

Component Alignment in Simultaneous Bilateral versus Unilateral Total Knee Arthroplasty.

PURPOSE: The purpose of this study was to investigate differences in component alignment between first and second knees in simultaneous bilateral total knee arthroplasty (SBTKA) and unilateral TKA (UTKA). MATERIALS AND METHODS: 274 SBTKAs and 198 UTKAs were included in study. Patients were divided into three groups as SBTKA on the right knee (group A), SBTKA on the left knee (group B) and UTKA (group C). Femoral and tibial component alignment was checked in both coronal plane (alpha [α] and beta [ß] angles) and sagittal plane (gamma [γ] and delta [δ] angles) radiographs. RESULTS: There were no statistically significant differences among groups in the preoperative anatomical varus angle and Kellgren-Lawrence gonarthrosis classification grade (p=0.139 and p=0.329, respectively). In the coronal plane, the alignment of femoral component (α angle) and tibial component (ß angle) was similar in all three groups (α angle, 95.01 vs. 95.14 vs. 94.9, p=0.945; ß angle, 90.03 vs. 89.67 vs. 89.98, p=0.483). The sagittal plane alignment of femoral component (γ angle) and tibial component (δ angle) did not show significant differences (γ angle, 7.04 vs. 6.98 vs. 7.00, p=0.132; δ angle, 86.56 vs. 87.41 vs. 86.73, p=0.610). CONCLUSIONS: The angular alignment of components was similar between SBTKA and UTKA.

One-stage Hip Reconstruction for Developmental Hip Dysplasia in Children over 8 Years of Age.

PURPOSE: This study was performed to assess the clinical and radiological outcomes following one-stage hip reconstruction, consisting of open reduction femoral shortening and pelvic osteotomy, for neglected developmental dislocation of the hip (DDH). MATERIALS AND METHODS: This is a retrospective analysis of 77 hips in 65 patients (46 females and 19 males; 12 had bilateral dislocations), operated at a Ghurki Trust Teaching Hospital in Pakistan between 2013 and 2015. The average age at surgery was 11.02±3.43 years. According to the Tönnis classification, there were 10, 14, 22, and 31 patients in grades 1, 2, 3, and 4, respectively. The pelvic procedure utilized in this study was triple osteotomy (47 hips) followed by double and Salter osteotomy (18 and 12 hips, respectively). Postoperative evaluations were conducted using the modified MacKay's scoring system (functional outcomes) and Severin's scoring method (radiological assessment). RESULTS: Postoperatively, there were 38 (49.4%), 19 (24.7%), 14 (18.2%), and 6 (7.8%) hips in Severin grade I, II, III and IV, respectively. According to the modified McKay criteria, there were 22 hips (28.6%) in excellent condition, 44 (57.1%) in good condition, 9 (11.7%) in fair condition and 2 (2.6%) in poor condition. Both patients with poor outcomes had an unstable, painful hip with evidence of avascular necrosis of the femoral head. CONCLUSION: Based on the results presented here, we recommend the single stage procedure of open reduction, femoral shortening and pelvic osteotomy for treatment of DDH in older children with good to excellent functional and radiological outcomes.

Capsular arthroplasty for neglected developmental dysplasia of hip.

INTRODUCTION: Treatment of developmental dysplasia of hip (DDH) diagnosed after 10 years of age is extremely difficult because of the soft tissue and bone deformities. In this study, we evaluated short-term results of a single-stage procedure performed with surgical hip dislocation, femoral shortening and capsular arthroplasty. PATIENTS AND METHODS: A retrospective review of charts of five patients with DDH, older than 10 years, who underwent capsular arthroplasty at Ghurki Trust Teaching Hospital between 2013 and 2015 was performed. Post-operative functional evaluation was performed using modified McKay's scoring system and radiographic assessment using Severin's scoring method at a minimum of 2-year follow-up. RESULTS: We present results of five patients (six hips) with a mean age of 18.16 years. All patients had limping gait and International Hip dysplasia Institute classification (IHDI) class 4 hip dislocation. Harris hip score showed a significant improvement (53.13 vs 84.16; p = 0.0001). Femoral shortening of 2-2.5 cm was done. Additional shelf procedure was required in one patient. This patient persistently has post-operative hip subluxation. All patients had good to excellent outcomes according to McKay classification. Post-operative Severin classification was 1A in all patients. No case of avascular necrosis of the femoral head was noted during the follow-up. CONCLUSION: Capsular arthroplasty with subtrochanteric shortening is a useful procedure for neglected cases of DDH in patients older than 10 years.

Salvage of infected non-union of the tibia with an Ilizarov ring fixator.

PURPOSE: To review outcomes of 24 patients who underwent Ilizarov ring fixation for infected nonunion of the tibia. METHODS: Medical records of 21 men and 3 women aged 13 to 74 (mean, 38) years who underwent Ilizarov ring fixation for infected non-union of the tibia were reviewed. The mean bone defect was 3.3 (range, 2-5) cm. The mean time from injury to presentation was 11.9 (range, 1-36) months. The mean number of previous surgeries was 2 (range, 0-14). A local flap was used in 2 patients and a free flap was used in one patient. Nine of the patients underwent Ilizarov ring fixation without soft tissue and bony resection, as inadequate stability was the reason for non-union. Patients were assessed using the Association for the Study and Application of the Method of Ilizarov criteria. RESULTS: Patients were followed up for a mean of 11 (range, 8-46) months. Functional outcome was excellent in 8 patients, good in 12, fair in 2, and failure in one, whereas bone union outcome was excellent in 6 patients, good in 14, fair in one, and poor in 2. The mean time to union was 8 (range, 3-31) months. The mean external fixation index was 4.2 (range, 1.5-15.7) cm/month. Complications encountered were pin tract infection (n=5), re-fracture (n=2), soft tissue impingement by Ilizarov rings (n=2), recurrence of wound infection (n=1), mal-union (n=1), and mortality (n=1). CONCLUSION: Ilizarov ring fixation is a viable option for infected non-union of the tibia. Adequate assessment of bone union is crucial before removal of fixator to prevent re-fracture.

Prophylaxis against heterotopic ossification after elbow and acetabular fractures - Do we really need it.

OBJECTIVE: To compare the efficacy and safety of prophylactic modalities for heterotopic ossification prevention after elbow and acetabular surgeries. METHODS: The retrospective chart review was conducted at the Aga Khan University Hospital and comprised record of patients who underwent open reduction and internal fixation for elbow and acetabular fractures between 2010 and 2013. Data was classified into three groups: Group A patients had received single dose of radiotherapy; Group B patients had received indomethacin, and Group C patients had not received any prophylaxis. Outcome variables included time-to-fracture healing, heterotopic ossification, non-union and wound infection. RESULTS: Of the 104patients 70(67.3%) had elbow fractures and 34(32.7%) had acetabular fractures. Out of the 70patients with elbow fractures, 28(27%) were in Group A, 24(23%) in Group B, and 18(17%) in Group C. In Group A, 4(22%) patients had wound infection compared to 1(5.5%) patient in Group C (p=0.131). One (4%) patient in Group B and 1(5.5%) in Group C developed heterotopic ossification (p=0.486). Non-union occurred in 1(4%) patient in Group B and 1(5.5%) in Group C. Out of the 34 patients with acetabular fractures, 11(32.3%) were in Group A, 10(29.4%) in Group B, and 13(38.2%) in Group C. In Group A, 2(18.2%) patients developed wound infection. Only 1(7.6%) patient in Group C developed heterotopic ossification. CONCLUSIONS: No role of radiotherapy or indomethacin was detected in the prevention of heterotopic ossification.

EuroSCORE vs. EuroSCORE II vs. Society of Thoracic Surgeons risk algorithm.

INTRODUCTION: This study presents a validation series for EuroSCORE II compared with the previous additive and logistic EuroSCORE and the Society of Thoracic Surgeons risk prediction algorithm. PATIENTS AND METHODS: Clinical data of 2004 patients undergoing isolated coronary artery bypass surgery between 2006 and 2010 were retrospectively collected and individual expected risks of death were calculated by all 3 risk prediction algorithms. Performance of these risk algorithms was evaluated in terms of discrimination and calibration. RESULTS: There were 76 deaths (3.8%) among 2004 patients. The mean EuroSCORE II predicted mortality was 3.72% ± 5.11%, additive EuroSCORE was 4.35% ± 3.65% and logistic EuroSCORE was 6.41% ± 10.06%. The additive EuroSCORE was better than EuroSCORE II in terms of both discrimination and calibration (C-statistic 0.866 and Hosmer-Lemeshow p value 0.230 vs. C-statistic 0.836 and Hosmer-Lemeshow p value 0.013 for EuroSCORE II). In a subset of 380 patients, we compared EuroSCORE II with the Society of Thoracic Surgeons risk prediction. Actual mortality was 2.89%. Predicted mortality by EuroSCORE II was 4.27% ± 5.22% and Society of Thoracic Surgeons risk prediction was 2.30% ± 4.16%. The area under the curve was 0.759 for EuroSCORE II and 0.898 for the Society of Thoracic Surgeons risk prediction, whereas the Hosmer-Lemeshow p value was 0.267 for EuroSCORE II and 0.981 for Society of Thoracic Surgeons risk prediction. CONCLUSION: The Society of Thoracic Surgeons risk prediction algorithm is a better risk assessment tool compared to additive and logistic EuroSCORE and EuroSCORE II in Pakistani patients.

Use of femoral nail with spiral blade in subtrochanteric fractures.

OBJECTIVE: The aim of this study was to evaluate the outcome of acute subtrochanteric fractures managed with intramedullary nail and spiral blade fixation of the proximal fragment. METHODS: Charts of 33 patients (17 males and 16 females) with acute subtrochanteric fractures operated with intramedullary nail and spiral blade at our institution between March 2006 and February 2011 were retrospectively reviewed. The most common (67%) mechanism of injury was ground-level fall, predominantly involving elderly patients. Results were evaluated in terms of union time, implant failure rate, infection rate and functional outcome. RESULTS: Mean duration of surgery was 2.4 hours and average length of hospital stay was 7 days. Mean radiological healing time was 16 weeks. Good healing occurred in 31 (94%) patients within 6 months of surgery. Uneventful healing occurred in 28 (85%) patients and 3 (9%) had delayed healing requiring dynamization in two patients and bone grafting in one. Implant failure occurred in 2 (6%) patients within 2 months of index surgery requiring repeat surgery. One (3%) patient had varus malunion. CONCLUSION: Intramedullary nailing with spiral blade is a good option for acute subtrochanteric fractures with promising results. We think that this is a superior device compared to conventional methods of fixation for subtrochanteric fractures.

Heart valve surgery: EuroSCORE vs. EuroSCORE II vs. Society of Thoracic Surgeons score.

BACKGROUND: This is a validation study comparing the European System for Cardiac Operative Risk Evaluation (EuroSCORE) II with the previous additive (AES) and logistic EuroSCORE (LES) and the Society of Thoracic Surgeons' (STS) risk prediction algorithm, for patients undergoing valve replacement with or without bypass in Pakistan. PATIENTS AND METHODS: Clinical data of 576 patients undergoing valve replacement surgery between 2006 and 2013 were retrospectively collected and individual expected risks of death were calculated by all four risk prediction algorithms. Performance of these risk algorithms was evaluated in terms of discrimination and calibration. RESULTS: There were 28 deaths (4.8%) among 576 patients, which was lower than the predicted mortality of 5.16%, 6.96% and 4.94% by AES, LES and EuroSCORE II but was higher than 2.13% predicted by STS scoring system. For single and double valve replacement procedures, EuroSCORE II was the best predictor of mortality with highest Hosmer and Lemmeshow test (H-L) p value (0.346 to 0.689) and area under the receiver operating characteristic (ROC) curve (0.637 to 0.898). For valve plus concomitant coronary artery bypass grafting (CABG) patients actual mortality was 1.88%. STS calculator came out to be the best predictor of mortality for this subgroup with H-L p value (0.480 to 0.884) and ROC (0.657 to 0.775). CONCLUSIONS: For Pakistani population EuroSCORE II is an accurate predictor for individual operative risk in patients undergoing isolated valve surgery, whereas STS performs better in the valve plus CABG group.

Effect of teriparatide on bone regenerate after distraction osteogenesis.

OBJECTIVE: To determine the effect of teriparatide on new bone formation in a rat model of distraction osteogenesis. METHODS: The experimental study was conducted at the Aga Khan University Hospital, Karachi, in November-December 2010, and comprised male Sprague-Dawley rats weighing 250gm each who were allocated to two treatment groups, teriparatide and saline, both given subcutaneously for 7 weeks. Femoral distraction was done for 3 weeks at the rate of 0.4mm/day, followed by a further 4 weeks for consolidation. New bone formation was assessed using X-ray scoring system, bone densitometry and histology. RESULTS: The 12 rats in the study were divided into two groups of 6(50%) each. All rats in the teriparatide group showed new bone formation whereas bone formation was present only in 2(33.3%) rats in the saline group. Bone densitometry showed that area (size) of the new bone formed adjacent to the margins of the osteotomy site as well as the total bone mineral content of the new bone was significantly higher (p<0.05) in the teriparatide group. Histological analysis showed larger but statistically insignificant (p>0.05) area of woven and trabecular new bone in the teriparatide group. CONCLUSIONS: The results suggested a promising role of parathyroid analogue therapy in distraction osteogenesis for promoting bone formation and consolidation. This may have strong clinical implications in cases of limb lengthening and bone transport.

Impact of unplanned excision on prognosis of patients with extremity soft tissue sarcoma.

Unplanned excision of soft tissue sarcomas (STSs) outside comprehensive tumor management centers necessitates the need for wide reexcision to achieve adequate margins. We retrospectively reviewed medical records of 135 patients with STS operated at our hospital with the goal of examining outcomes, in terms of local recurrence (LR) and metastasis rate (MR), of reexcision following unplanned excision of STS and comparing results with those of first-time planned surgery. Eighty-four patients had their first-time surgery and 51 patients had come to us following unplanned excision at prereferral hospital. Mean age of all patients was 41.8 ± 21.9 years. The LR and MR was 14.3% and 8.3%, respectively, in patients undergoing first resection, whereas it was 21.4% and 13.7%, respectively, in patients undergoing revision surgery. Average duration from previous unplanned excision was 8 months. Twelve patients were referred immediately after excised specimen revealed STS, while 39 patients presented after evident local recurrence. Wide reexcision was attempted in 48 patients while three patients need amputation. Adjuvant radiotherapy was administered in all patients undergoing limb-sparing surgery. Ten patients needed adjuvant chemotherapy. We conclude that wide reexcision of STS has poorer outcomes compared to planned excision. Therefore, patients with soft tissue masses should be managed by multidisciplinary oncology team at specialized cancer centers.