Exophytic Squamous Cell Carcinoma of the Scalp: A Case Report.

Squamous cell carcinoma (SCC) is the second-most common clinical presentation of non-melanoma skin cancer. Despite its prevalence, the rate of growth and development of SCC lesions is low. We present a case report of an exophytic SCC of the midline scalp. Over approximately 18 months, the exophytic portion of this lesion grew to a size of 8.5 x 7 cm due to the fact that the patient did not seek medical attention. The patient suffered from many predisposing factors including active smoking status, type II diabetes, and significant previous sun exposure. In addition to these predisposing factors, the patient did not have comprehensive health insurance to cover outpatient medical care. This case highlights the importance of early intervention in the management of head and neck skin cancers and the negative impact of delayed treatment.

Development of a sacral fracture model to demonstrate effects on sagittal alignment.

PURPOSE: To develop a modeling framework to predict the secondary consequences on spinal alignment following correction and to demonstrate the impact of pedicle subtraction osteotomy (PSO) location on sagittal alignment. METHODS: Six patients were included, and pelvic incidence (PI) was measured. Full-length standing radiographs were uploaded into PowerPoint and manipulated to model S1-S2 joint line sacral fractures at 15°, 20°, 25°, and 30°. PSO corrections with hinge points at the anterior superior corner and vertical midpoint of the L3-5 vertebral bodies were modeled. Anterior translation (AT) and vertical shortening (VS) were calculated for the six PSO locations in the four fracture angle (FA) models. RESULTS: PI had a strong effect in the mixed AT and VS models (P < 0.001). Both AT and VS were significantly different from zero at all FA (p < 0.001), and pairwise comparisons revealed all FA were different from each other with respect to both AT and VS after adjusting for PSO location (p < 0.001), increasing as FA increased. Varying PSO location resulted in significant differences in AT when comparing all locations (p < 0.001). AT was greatest for all FA in all patients when the PSO correction was performed at the L3-AS (p < 0.001). There were significant differences in VS when comparing the L5-Mid PSO location to the L3-AS, L3-Mid, L4-AS, and L4-Mid PSO locations (p < 0.034). CONCLUSION: PSO correction superior to a sacral fracture resulted in AT and VS of the spine. It is crucial that these changes in spinal measures be predicted and accounted for to optimize patient sagittal alignment and outcomes.

Sagittal radiographic parameters in the presence of lumbosacral transitional vertebra (LSTV): relationships between measurements using the upper vs lower transitional vertebra.

PURPOSE: Optimization of spinopelvic sagittal parameters in spinal deformity surgery have been shown to correlate with surgical outcomes. Commonly used parameters include pelvic incidence (PI), lumbar lordosis (LL) and PI-LL mismatch. Presence of lumbosacral transitional vertebra (LSTV) introduces variability regarding which endplate is considered the sacral endplate. This study aimed to determine the mathematical relationships between measurements using the upper transitional vertebra (UTV) versus the lower transitional vertebra (LTV). METHODS: The property that internal angles of a triangle sum to 180° was used to create a system of equations to resolve the relationship between the PI-LL mismatch of the UTV and of the LTV. The ultimate relationship was employed on a lateral radiograph of a patient with LSTV for validation. RESULTS: It is possible to compute the PI-LL mismatch using either UTV or LTV and convert to the corresponding PI-LL when using the other vertebra simply by measuring one additional angle (PI-LL)L = (PI-LL)U + X. This angle X is defined by segments connecting the center of the femoral head to the midpoints of the superior endplates of the UTV and LTV. Using the LTV yields a larger PI-LL mismatch value. CONCLUSION: In patients with LSTV, it is controversial whether the UTV or LTV should be used as the sacral endplate for sagittal measurements. With this mathematical relationship, rather than completing two sets of measurements, the surgeon would only need to measure one set and the additional angle X to determine the resultant PI-LL mismatch for the other transitional vertebra.

COVID-19: Impact on Orthopaedic Graduate Medical Education in the U.S.: AOA Critical Issues Symposium.

ABSTRACT: The COVID-19 crisis has challenged the U.S. health-care system in a variety of ways, including how we teach and train orthopaedic surgery residents and fellows. During the spring of 2020, the cessation of all elective surgical procedures and the diminished number of outpatient visits challenged graduate medical education. While residency programs in less affected areas may not have had to make many dramatic adjustments, some of those located in pandemic hotspots had to redirect trainees from orthopaedic rotations to COVID-19 units. No matter the region, the time that trainees have spent in rotations has been altered, and absences have occurred due to quarantines. This symposium summarizes the impact of restrictions related to the COVID-19 pandemic on residency and fellowship programs from the perspectives of the Accreditation Council for Graduate Medical Education (ACGME), a program director, and a graduating resident. Although new opportunities for virtual curricula, virtual surgical simulation, and virtual interviews have been innovated, residency programs and residents report primarily a negative effect from the pandemic due to decreased surgical volumes and the limitation of patient-care experiences. Ultimately, program directors have an obligation to the program, the trainee, and the general public to graduate only those residents and fellows who are truly prepared to practice independently; they have the responsibility of making the final decision regarding graduation. The COVID-19 pandemic has continued to underscore the need for competency-based medical education. Assessing competency includes evaluation of the knowledge, the operative skills, the nonoperative patient-care skills, and the professional behavior of each and every individual graduating from orthopaedic residency and fellowship training programs. A hybrid model for time and competency-based training, with established national standards not only for accreditation for our training programs but also for board certification of our graduating residents, was enhanced by the COVID-19 pandemic and is highlighted in this symposium.

Culture and characterization of various porcine integumentary-connective tissue-derived mesenchymal stromal cells to facilitate tissue adhesion to percutaneous metal implants.

BACKGROUND: Transdermal osseointegrated prosthesis have relatively high infection rates leading to implant revision or failure. A principle cause for this complication is the absence of a durable impervious biomechanical seal at the interface of the hard structure (implant) and adjacent soft tissues. This study explores the possibility of recapitulating an analogous cellular musculoskeletal-connective tissue interface, which is present at naturally occurring integumentary tissues where a hard structure exits the skin, such as the nail bed, hoof, and tooth. METHODS: Porcine mesenchymal stromal cells (pMSCs) were derived from nine different porcine integumentary and connective tissues: hoof-associated superficial flexor tendon, molar-associated periodontal ligament, Achilles tendon, adipose tissue and skin dermis from the hind limb and abdominal regions, bone marrow and muscle. For all nine pMSCs, the phenotype, multi-lineage differentiation potential and their adhesiveness to clinical grade titanium was characterized. Transcriptomic analysis of 11 common genes encoding cytoskeletal proteins VIM (Vimentin), cell-cell and cell-matrix adhesion genes (Vinculin, Integrin ß1, Integrin ß2, CD9, CD151), and for ECM genes (Collagen-1a1, Collagen-4a1, Fibronectin, Laminin-α5, Contactin-3) in early passaged cells was performed using qRT-PCR. RESULTS: All tissue-derived pMSCs were characterized as mesenchymal origin by adherence to plastic, expression of cell surface markers including CD29, CD44, CD90, and CD105, and lack of hematopoietic (CD11b) and endothelial (CD31) markers. All pMSCs differentiated into osteoblasts, adipocytes and chondrocytes, albeit at varying degrees, under specific culture conditions. Among the eleven adhesion genes evaluated, the cytoskeletal intermediate filament vimentin was found highly expressed in pMSC isolated from all tissues, followed by genes for the extracellular matrix proteins Fibronectin and Collagen-1a1. Expression of Vimentin was the highest in Achilles tendon, while Fibronectin and Col1agen-1a1 were highest in molar and hoof-associated superficial flexor tendon bone marrow, respectively. Achilles tendon ranked the highest in both multilineage differentiation and adhesion assessments to titanium metal. CONCLUSIONS: These findings support further preclinical research of these tissue specific-derived MSCs in vivo in a transdermal osseointegration implant model.