How do different marine engine fuels and wet scrubbing affect gaseous air pollutants and ozone formation potential from ship emissions?

Sulphur Emission Control Areas (SECAs), mandated by the International Maritime Organization (IMO), regulate fuel sulphur content (FSC) to mitigate the environmental and health impact of shipping emissions in coastal areas. Currently, FSC is limited to 0.1% (w/w) within and 0.5% (w/w) outside SECAs, with exceptions for ships employing wet sulphur scrubbers. These scrubbers enable vessels using non-compliant fuels such as high-sulphur heavy fuel oils (HFOs) to enter SECAs. However, while sulphur reduction via scrubbers is effective, their efficiency in capturing other potentially harmful gases remains uncertain. Moreover, emerging compliant fuels like highly aromatic fuels or low-sulphur blends lack characterisation and may pose risks. Over three years, we assessed emissions from an experimental marine engine at 25% and 75% load, representative of manoeuvring and cruising, respectively. First, characterizing emissions from five different compliant and non-compliant fuels (marine gas oil MGO, hydro-treated vegetable oil HVO, high-, low- and ultra-low sulphur HFOs), we calculated emission factors (EF). Then, the wet scrubber gas-phase capture efficiency was measured using compliant and non-compliant HFOs. NOx EF varied among fuels (5200-19700 mg/kWh), with limited scrubber reduction. CO (EF 750-13700 mg/kWh) and hydrocarbons (HC; EF 122-1851 mg/kWh) showed also insufficient abatement. Carcinogenic benzene was notably higher at 25% load and about an order of magnitude higher with HFOs compared to MGO and HVO, with no observed scrubber reduction. In contrast, carbonyls such as carcinogenic formaldehyde and acetaldehyde, acting as ozone precursors, were effectively scrubbed due to their polarity and water solubility. The ozone formation potential (OFP) of all fuels was examined. Significant EF differences between fuels and engine loads were observed, with the wet scrubber providing limited or no reduction of gaseous emissions. We suggest enhanced regulations and emission abatements in the marine sector to mitigate gaseous pollutants harmful to human health and the environment.

Myomucosal composite graft: A simple technique for full-thickness vermilion defects of the lower lip.

Reconstruction of vermillion defects of the lower lip requires careful consideration of functional and aesthetic aspects. Traditionally, various local flap methods involving tissue advancement from the corner of the mouth, lateral chin, and medial cheek have been commonly employed to fill lower lip defects. However, these approaches have inherent limitations, which include technical complexity, disruption of the orbicularis oris muscle, lip tightening, microstomia, and visible scarring. To overcome these limitations, we employed a free myomucosal composite graft from the lower lip to reconstruct small to medium vermilion defects. Our technique is based on a simple and reproducible surgical approach that facilitates natural volume rearrangement of tissues. Moreover, this method enables precise inset and tension-free repair, prevents lip tightening, and offers excellent aesthetic outcomes with no vertical scarring and appropriate color matching with surrounding tissues.

Geriatric Vertebral Compression Fracture: A Database Study Characterizing Use and Trends for Prescribed Thoracic/Lumbar Orthoses.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: Geriatric vertebral compression fractures are the most common fracture associated with osteoporosis. Using a large national database, the current study aimed to examine and characterize bracing trends for geriatric thoracic/lumbar compression fracture management. METHODS: The current study utilized the PearlDiver database from 2015-2021. Patients who suffered thoracic/lumbar compression fractures (fifth thoracic to the fifth lumbar vertebra [T5-L5]) were identified. Exclusion criteria included patients less than 65 years old or an indication of infection or neoplasm. Patients who received a brace within 90-days after the initial diagnosis of thoracic/lumbar compression fracture were abstracted and characterized overall and by fracture level. Multivariable logistic regression was performed to assess for correlation with bracing trends. RESULTS: In total 290 388 patients met inclusion criteria and suffered a thoracic/lumbar compression fracture (greatest incidence at the thoracolumbar junction). Of these, bracing was only prescribed for 4263 (1.5%), with the greatest variance of 1.5% by level. Independent predictors of bracing were geographic region (relative to northeast, west WE odds ratio [OR] 1.31, Midwest OR 1.20), younger age (OR 1.27 per decade), female sex (OR 1.17), and ECI (OR 1.02 per 2-point increase) (P < .05 for each). CONCLUSION: Overall, the current study examined over a quarter of a million patients who suffered a T5-L5 compression fractures and found that only 1.5% of patients were braced. This low percentage, and that greatest predictor for bracing was non-clinical (geographic region), highlight the inconsistency of this practice and may be useful for developing treatment algorithms.

Pre-contoured patient-specific rods result in superior immediate sagittal plane alignment than surgeon contoured rods in adolescent idiopathic scoliosis.

Background: Adolescent idiopathic scoliosis (AIS) surgery typically involves posterior spinal fusion (PSF) using rods contoured by the surgeon, which may be time-consuming and may not reliably restore optimal sagittal alignment. However, pre-contoured patient-specific rods may more optimally restore sagittal spinal alignment. This study evaluates the radiographic outcomes of AIS patients who underwent PSF utilizing surgeon contoured vs. pre-contoured rods. Methods: This is a retrospective cohort study of AIS patients who underwent PSF with either surgeon contoured or pre-contoured rods. Demographics, Lenke classification, fused levels, osteotomies, estimated blood loss (EBL), and surgical time were also obtained via chart review. Coronal curve magnitude, T5-T12 thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), PI-LL mismatch, and T1 pelvic angle (TPA) were obtained pre-operatively, postoperatively and at last follow up. Outcome measures included rate of achievement of postoperative radiographic alignment goals (TK between 20 and 40 degrees, PI-LL mismatch within 10 degrees, and TPA <14 degrees). Predicted post-operative sagittal alignment was also compared with observed measurements. Student's and paired t-tests were performed to determine significant mean differences for continuous variables, and chi-square for categorical variables. Results: No differences were found in demographics, Lenke classification, preop radiographic measurements, fused levels, osteotomies, EBL, and surgical time in the surgeon contoured cohort (n=36; average follow up 11.3 months) and pre-contoured cohort (n=22; average follow up 9.7 months). At last follow up, 95.5% of patients with pre-contoured rods vs. 61.1% of patients with surgeon contoured rods (P=0.004) met TK goal. During assessment of first standing postoperative X-ray, 72.7% of patients with pre-contoured rods vs. 33.3% of patients with surgeon contoured rods met PI-LL mismatch goal (P=0.004). Other radiographic measurements were similar. Artificial intelligence (AI) predicted and observed differences for the pre-contoured group were 3.7 for TK (P=0.005), -7.6 for PI-LL mismatch (P=0.002), and -2.6 for TPA (P=0.11). Conclusions: AI and pre-contoured rods help achieve global sagittal balance with high accuracy and improved kyphosis restoration and PI-LL mismatch than surgeon contoured rods in AIS patients.

Functional evaluation of Septal L-strut extension graft in East Asians.

BACKGROUND: The septal L-strut extension graft (SLEG) consists of anterior extended spreader graft and caudal septal extension graft. SLEG is used to increase the anterocaudal projection from a low-profile nose by creating the de-novo septum. This retrospective study verified the effectiveness of SLEG in improving the nasal function in East Asians. MATERIALS: Medical records of patients who underwent septorhinoplasty with SLEG were retrospectively reviewed. The clinical features showed under-projected lower two-thirds of the nose with septal deviation, saddle nose, and short nose. We analyzed the post-operative changes in the NOSE score and variables of nasal geometry measured using acoustic rhinometry through long-term follow-up. RESULTS: Patients were divided into two groups, those who underwent SLEG with turbinoplasty (Group A) and SLEG alone (group B). The NOSE scores decreased significantly in groups A and B, and the improvement was statistically more significant in Group A (p < 0.05). Acoustic rhinometry showed an increase in nasal cavity volume (VOL1) on the deviated side in Group A, and an increase in minimal cross-sectional area 1 (MCA1) on the deviated side in Group B (p < 0.05). The non-deviated side did not show significant reduction in MCA1 and VOL1 after SLEG with or without turbinoplasty. Thus, SLEG, by itself, improved airway function in East Asians. CONCLUSIONS: SLEG has proven to be valuable in improving nasal function.

Evaluating micronized adipose tissue niche and artificial dermis grafts following nonmelanoma skin cancer excision: a pilot study.

BACKGROUND: Recently, micronized adipose tissue (MAT) grafts have shown promising results in wound healing, including diabetic ulcers. OBJECTIVE: To assess the possibility of using 3D printed MAT niche grafts in the management of skin and soft tissue defects resulting from non-melanoma skin cancer (NMSC) resections. MATERIALS AND METHODS: A retrospective feasibility study was conducted on patients with skin and soft tissue defects resulting from NMSC resections. Twenty-one patients were treated using either artificial dermis (n = 11) or MAT niche (n = 10) grafting. Healing time and POSAS scores were compared. The Mann-Whitney U test and the Pearson chi-square test were used in statistical analysis to compare between and within groups based on preoperative and postoperative measurements. RESULTS: Wounds in the MAT niche group reepithelialized significantly faster than those in the artificial dermis group (mean [SD] 39.2 [11.4] days vs 63.7 [34.8] days; P = .04). In the 21 scar parameters evaluated, the MAT niche group demonstrated significantly superior outcomes in only 2 parameters based on operator assessment scores: relief (mean [SD] 1.6 [0.7] vs 2.2 [0.6]; P = .047) and scar contracture (mean [SD] 1.3 [0.5] vs 2.5 [1.0]; P = .011). CONCLUSION: This study proves the feasibility of exploring the effects of MAT niche grafting following NMSC excision on healing time and specific parameters of scarring, including scar relief and scar contracture.

A 10-year perspective on the question of whether surgeries for adolescent idiopathic scoliosis are "one and done"?

PURPOSE: Posterior scoliosis fusion (PSF) for adolescent idiopathic scoliosis (AIS) is considered a highly successful surgery with excellent outcomes. However, especially as many patients "graduate" from their pediatric surgeons, there is the need to quantify the long-term outcomes of such surgeries. METHODS: The 2010-2022 Pearldiver M161 dataset was queried for those who were 10 to 18 years old with AIS undergoing PSF with at least 10 years follow-up. Patient characteristics were abstracted. Reoperations were identified based on coding for any subsequent thoracic/lumbar surgery/revision. The 10-year reoperation rate and reasons for reoperation were determined, and multivariate regression was performed to determine risk factors. RESULTS: In total, 3,373 AIS PSF patients were identified. Of the study cohort, 324 (9.6%) underwent reoperation within 10-years with an interquartile range for timing of surgery of 81-658 days, of which 29.6% were done for infection. Reoperations were done within the first three months for 152 (46.9% of reoperations), three months to 2 years for 97 (29.9%), and 2 years to 10 years for 74 (22.8%). Based on multivariate regression, need for reoperation was associated with male sex (OR: 1.70), asthma (OR: 1.36) and greater than thirteen segments of instrumentation (OR: 1.48) (p < 0.05 for each) but not age, other comorbidities, or insurance. CONCLUSIONS: The current study of a large national AIS PSF population found 9.6% to undergo reoperation in the 10 years following their index operation. Although specifics about the curve pattern could not be determined, the reoperation incidence and correlation with specific risk factors are notable and important for patient counselling.

Physical Therapy Utilization After Single-level Posterior Lumbar Fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: Characterize physical therapy (PT) utilization following single-level posterior lumbar fusion (PLF). SUMMARY OF BACKGROUND DATA: PLF is a common procedure that is increasing in frequency. After such surgeries, PT may be considered to facilitate mobilization and return to activities. However, the usage of such therapy has not been well-characterized in the literature. MATERIALS AND METHODS: Patients undergoing single-level PLF were identified from the 2010 to 2021 PearlDiver administrative database. These patients were stratified based on usage of therapy, home versus outpatient therapy, and timing of therapy within the year after surgery. To determine predictors of therapy, patient characteristics were determined and multivariable regressions were performed. RESULTS: A total of 213,240 patients undergoing single-level PLF were identified, of which therapy was done in the year after surgery for 63,231 (29.0%, of which home therapy accounted for 16.5% of therapy visits). Of those who utilized PT, the average number of visits was 10.6±10.6. Home therapy peaked within the first month after surgery and outpatient therapy peaked at month two. Factors associated with any PT following PLF in decreasing odds ratio (OR) were having commercial insurance (OR: 1.68), being from the Northeast (OR: 1.41), age (OR: 1.13 for 70+ of age) female sex (OR: 1.09), and ECI (OR: 1.04 per point) ( P <0.001 for all). Of those who received therapy, factors associated with home PT utilization were being from the Northeast (OR: 2.55), age (OR: 1.91 for 70+ of age), Medicaid insurance (OR: 1.48), female sex (OR: 1.39), and interbody fusion (OR:1.07) ( P <0.001 for all). CONCLUSIONS: After single-level PLF, the minority of patients received home or outpatient PT. Of those who did, there was significant variation in the number of visits, with nonmedical factors such as insurance plan and geographic region being strongly associated suggesting room for more consistent practice patterns. LEVEL OF EVIDENCE: Level 3.