Faculty Bibliography

BACKGROUND:The hand is highly visible and contributes to an individual's aesthetic image and perceived age. Current perspectives on hand aesthetics are primarily based on expert opinion rather than on lay population perspectives, which are less understood. Our study explores general population perceptions on the features that contribute most to an attractive hand. METHODS:Participants rated the attractiveness of 20 standardized hands as well as the appearance based on each characteristic: freckles, hair presence, skin tone, wrinkles, vein appearance, and soft tissue volume. The relative importance of each feature was assessed by comparison with overall attractiveness scores through multivariate analysis of variance. RESULTS:A total of 223 participants completed the survey. Soft tissue volume ( r = 0.73) was most strongly correlated with overall attractiveness, followed by wrinkles ( r = 0.71), skin tone consistency ( r = 0.69), veins ( r = 0.65), freckles ( r = 0.61), and hair ( r = 0.47). Female hands were perceived as more attractive, with a mean rating of 4.7 of 10, compared with 4.4 in males ( P < 0.001). Participants correctly identified the gender of 90.4% of male hands and 65.0% of female hands. Age was strongly inversely correlated with attractiveness ( r = -0.80). CONCLUSIONS:Soft tissue volume is the most important factor in lay perception of hand aesthetics. Female and younger hands were perceived as more attractive. Hand rejuvenation may be optimized by prioritizing soft tissue volume with filler or fat grafting, with secondary priority on resurfacing to address skin tone and wrinkling. An understanding of the factors most important to patients in aesthetic appearance is critical to achieving a pleasing result.

The present study aimed to evaluate the effect of dipyridamole, an indirect adenosine 2A receptors (A_2AR), on the osseointegration of titanium implants in a large, translational pre-clinical model. Sixty tapered, acid-etched titanium implants, treated with four different coatings ((i) Type I Bovine Collagen (control), (ii) 10 μM dipyridamole (DIPY), (iii) 100 μM DIPY, and (iv) 1000 μM DIPY), were inserted in the vertebral bodies of 15 female sheep (weight ~65 kg). Qualitative and quantitative analysis were performed after 3, 6, and 12 weeks in vivo to assess histological features, and percentages of bone-to-implant contact (%BIC) and bone area fraction occupancy (%BAFO). Data was analyzed using a general linear mixed model analysis with time in vivo and coating as fixed factors. Histomorphometric analysis after 3 weeks in vivo revealed higher BIC for DIPY coated implant groups (10 μM (30.42% ± 10.62), 100 μM (36.41% ± 10.62), and 1000 μM (32.46% ± 10.62)) in comparison to the control group (17.99% ± 5.82). Further, significantly higher BAFO was observed for implants augmented with 1000 μM of DIPY (43.84% ± 9.97) compared to the control group (31.89% ± 5.46). At 6 and 12 weeks, no significant differences were observed among groups. Histological analysis evidenced similar osseointegration features and an intramembranous-type healing pattern for all groups. Qualitative observation corroborated the increased presence of woven bone formation in intimate contact with the surface of the implant and within the threads at 3 weeks with increased concentrations of DIPY. Coating the implant surface with dipyridamole yielded a favorable effect with regard to BIC and BAFO at 3 weeks in vivo. These findings suggest a positive effect of DIPY on the early stages of osseointegration.

The benefits of tissue expansion go unrealized if flap design and coverage concepts do not exist in pre-operative thinking. Without proper analysis, the surgeon will likely burden the patient with more expanders than necessary. Tissue coverage needs can be simplified in forms of triangles and rectangles to determine expanded tissue advancement. Single or double back cuts allow usage of all the expanded tissue. Furthermore, early subtotal excisions, especially in children less than four months old, can reduce the number of expanders required. With methods presented herein, the face can be resurfaced with better color and less distortion. Eyebrows should be maintained and positioned by keeping the lower frontalis muscles intact. Cheeks can be covered with a large "Schrudde" design and color can be improved by using upper neck skin preferentially over lower neck harvest. Laser hair removal allows larger swaths of forehead to be covered by hair-bearing scalp tissue. Prior incisional delay can expedite success with no tissue loss. The results speak for themselves when surfaces are covered with large, expanded flaps which are expeditiously harvested.

Surgeons often encounter patients with realistic goals yet who desire unrealistic means of achieving them. This tension is compounded when surgeons consult with patients eager to revise a prior gender-affirming procedure completed by another surgeon. Two key factors of ethical and clinical relevance are that (1) a consulting surgeon's job is complicated when a population-specific evidence base is lacking and (2) a patient's marginalization is exacerbated by their having suffered the downstream effects of compromised initial access to comprehensive, realistic surgical care. This case commentary about revision of gender-affirming phalloplasty canvasses the pitfalls of a limited evidence base and focuses on strategies surgeons can use to help guide consultation. In particular, informed consent discussion may need to reframe a patient's expectations about clinical accountability for irreversible interventions.

UNLABELLED:Fat grafting is an effective treatment for craniofacial deformities. Stromal vascular fraction (SVF) is a concentrated form of adipose derived stem cells that can be isolated from fat. The aim of this clinical trial was to assess the impact of SVF enrichment on craniofacial fat grafting. METHODS/UNASSIGNED:Twelve subjects with at least two regions of craniofacial volume deficit were enrolled, and they underwent fat grafting with SVF-enriched or standard fat grafting to each area. All patients had bilateral malar regions injected with SVF-enriched graft on one side and control standard fat grafting to the contralateral side. Outcome assessments included demographic information, volume retention determined by CT scans, SVF cell populations assessed by flow cytometry, SVF cell viability, complications, and appearance ratings. Follow-up was 9 months. RESULTS/UNASSIGNED:0.027). CONCLUSIONS/UNASSIGNED:Autologous fat transfer for reconstruction of craniofacial defects is effective and safe, leading to reliable volume retention. However, SVF enrichment does not significantly impact volume retention.

UNLABELLED:Head and neck reconstruction poses unique challenges due to the complex structure of the region. Primary goals include soft-tissue coverage, adequate color and texture match, and minimal donor-site morbidity. Local and musculocutaneous regional flaps have largely been replaced with fasciocutaneous free flaps (FFF) over recent years. The supraclavicular artery island flap (SCAIF), a locoregional, fasciocutaneous, axially-based flap, has been shown to produce similar outcomes to FFF. We present our 15-year experience using the SCAIF for head and neck reconstruction, discuss its evolution, and provide case examples for its range of indications. METHODS/UNASSIGNED:Retrospective chart review identified 128 patients who underwent reconstruction of the head and neck with the SCAIF between the years 2006-2021 at Tulane University Medical Center. Patient demographics, lengths of stay, operative times, surgical indications, and complications were recorded. RESULTS/UNASSIGNED:The cohort mean age was 66.9 years. Mean lengths of stay and follow-up times were 6.9 days and 9.1 months, respectively. The most common indications for SCAIF reconstruction were recurrent radiated neck disease (n=27, 21.1%), pharyngeal wall defects (n=23, 18.0%), and parotidectomy defects (n=21, 16.4%). Overall complication rate was 17.2%. Partial thickness flap loss (5.5%), contained pharyngeal leak (3.2%), and distal tip necrosis (2.4%) were the most common complications. No functional donor site morbidity was encountered. CONCLUSIONS/UNASSIGNED:The SCAIF is a versatile, fasciocutaneous, axially-based flap able to produce similar outcomes to FFF in the reconstruction of the head and neck region while reducing costs, lengths of stay, operative times, and donor site morbidity.

Sodium glucose cotransporter-2 inhibitors (SGLT2is) promote urinary glucose excretion and decrease plasma glucose levels independent of insulin. Canagliflozin (CANA) is an SGLT2i, which is widely prescribed, to reduce cardiovascular complications, and as a second-line therapy after metformin in the treatment of type 2 diabetes mellitus. Despite the robust metabolic benefits, reductions in bone mineral density (BMD) and cortical fractures were reported for CANA-treated subjects. In collaboration with the National Institute on Aging (NIA)-sponsored Interventions Testing Program (ITP), we tested skeletal integrity of UM-HET3 mice fed control (137 mice) or CANA-containing diet (180 ppm, 156 mice) from 7 to 22 months of age. Micro-computed tomography (micro-CT) revealed that CANA treatment caused significant thinning of the femur mid-diaphyseal cortex in both male and female mice, did not affect trabecular bone architecture in the distal femur or the lumbar vertebra-5 in male mice, but was associated with thinning of the trabeculae at the distal femur in CANA-treated female mice. In male mice, CANA treatment is associated with significant reductions in cortical bone volumetric BMD by micro-CT, and by quantitative backscattered scanning electron microscopy. Raman microspectroscopy, taken at the femur mid-diaphyseal posterior cortex, showed significant reductions in the mineral/matrix ratio and an increased carbonate/phosphate ratio in CANA-treated male mice. These data were supported by thermogravimetric assay (TGA) showing significantly decreased mineral and increased carbonate content in CANA-treated male mice. Finally, the sintered remains of TGA were subjected to X-ray diffraction and showed significantly higher fraction of whitlockite, a calcium orthophosphate mineral, which has higher resorbability than hydroxyapatite. Overall, long-term CANA treatment compromised bone morphology and mineral composition of bones, which likely contribute to increased fracture risk seen with this drug.

BACKGROUND/UNASSIGNED:" osseodensification rotary drilling compacts the bone fragments into the osteotomy walls, creating nucleating sites for regeneration. METHODS/UNASSIGNED:This study aimed to compare both manual versus rotary Osseodensification (OD) instrumentation as well as two different pedicle screw thread designs in a controlled split animal model in posterior lumbar stabilization to determine the feasibility and potential advantages of each variable with respect to mechanical stability and histomorphology. A total of 164 single thread (82 per thread configuration), pedicle screws (4.5 × 35 mm) were used for the study. Each animal received eight pedicles (four per thread design) screws, which were placed in the lumbar spine of 21 adult sheep. One side of the lumbar spine underwent rotary osseodensification instrumentation, while the contralateral underwent conventional, hand, instrumentation. The animals were euthanized after 6- and 24-weeks of healing, and the vertebrae were removed for biomechanical and histomorphometric analyses. Pullout strength and histologic analysis were performed on all harvested samples. RESULTS/UNASSIGNED: = 0.026) greater pullout strength (1060.6 N ± 181) relative to hand instrumentation (769.3 N ± 181) at the 24-week healing time point. Histomorphometric analysis exhibited significantly higher degrees of bone to implant contact for the rotary instrumentation only at the early healing time point (6 weeks), whereas bone area fraction occupancy was statistically higher for rotary instrumentation at both healing times. The levels of soft tissue infiltration were lower for pedicle screws placed in osteotomies prepared using OD instrumentation relative to hand instrumentation, independent of healing time. CONCLUSION/UNASSIGNED:The rotary instrumentation yielded enhanced mechanical and histologic results relative to the conventional hand instrumentation in this lumbar spine stabilization model.

The hypothesis that sustained G protein-coupled receptor (GPCR) signaling from endosomes mediates pain is based on studies with endocytosis inhibitors and lipid-conjugated or nanoparticle-encapsulated antagonists targeted to endosomes. GPCR antagonists that reverse sustained endosomal signaling and nociception are needed. However, the criteria for rational design of such compounds are ill-defined. Moreover, the role of natural GPCR variants, which exhibit aberrant signaling and endosomal trafficking, in maintaining pain is unknown. Herein, substance P (SP) was found to evoke clathrin-mediated assembly of endosomal signaling complexes comprising neurokinin 1 receptor (NK₁R), Gα_q/i, and βarrestin-2. Whereas the FDA-approved NK₁R antagonist aprepitant induced a transient disruption of endosomal signals, analogs of netupitant designed to penetrate membranes and persist in acidic endosomes through altered lipophilicity and pKa caused sustained inhibition of endosomal signals. When injected intrathecally to target spinal NK₁R+ve neurons in knockin mice expressing human NK₁R, aprepitant transiently inhibited nociceptive responses to intraplantar injection of capsaicin. Conversely, netupitant analogs had more potent, efficacious, and sustained antinociceptive effects. Mice expressing C-terminally truncated human NK₁R, corresponding to a natural variant with aberrant signaling and trafficking, displayed attenuated SP-evoked excitation of spinal neurons and blunted nociceptive responses to SP. Thus, sustained antagonism of the NK₁R in endosomes correlates with long-lasting antinociception, and domains within the C-terminus of the NK₁R are necessary for the full pronociceptive actions of SP. The results support the hypothesis that endosomal signaling of GPCRs mediates nociception and provides insight into strategies for antagonizing GPCRs in intracellular locations for the treatment of diverse diseases.