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Resident macrophages exist in a variety of tissues, including tendon, and play context-specific roles in their tissue of residence. In this study, we define the spatiotemporal distribution and phenotypic profile of tendon resident macrophages and their crosstalk with neighboring tendon fibroblasts and the extracellular matrix (ECM) during murine tendon development, growth, and homeostasis. Fluorescent imaging of cryosections revealed that F4/80+ tendon resident macrophages reside adjacent to Col1a1-CFP+ Scx-GFP+ fibroblasts within the tendon fascicle from embryonic development (E15.5) into adulthood (P56). Through flow cytometry and qPCR, we found that these tendon resident macrophages express several well-known macrophage markers, including Adgre1 (F4/80), Mrc1 (CD206), Lyve1, and Folr2, but not Ly-6C, and express the Csf1r-EGFP (“MacGreen”) reporter. The proportion of Csf1r-EGFP+ resident macrophages in relation to the total cell number increases markedly during early postnatal growth, while the density of macrophages per mm2 remains constant during this same time frame. Interestingly, proliferation of resident macrophages is higher than adjacent fibroblasts, which likely contributes to this increase in macrophage proportion. The expression profile of tendon resident macrophages also changes with age, with increased pro-inflammatory and anti-inflammatory cytokine expression in P56 compared to P14 macrophages. In addition, the expression profile of limb tendon resident macrophages diverges from that of tail tendon resident macrophages, suggesting differential phenotypes across anatomically and functionally different tendons. As macrophages are known to communicate with adjacent fibroblasts in other tissues, we conducted ligand-receptor analysis and found potential two-way signaling between tendon fibroblasts and resident macrophages. Tendon fibroblasts express high levels of Csf1, which encodes macrophage colony stimulating factor (M-CSF) that acts on the CSF1 receptor (CSF1R) on macrophages. Importantly, Csf1r-expressing resident macrophages preferentially localize to Csf1-expressing fibroblasts, supporting the “nurturing scaffold” model for tendon macrophage patterning. Lastly, we found that tendon resident macrophages express high levels of ECM-related genes, including Mrc1 (mannose receptor), Lyve1 (hyaluronan receptor), Lair1 (type I collagen receptor), Ctss (elastase), and Mmp13 (collagenase), and internalize DQ Collagen in explant cultures. Overall, our study provides insights into the potential roles of tendon resident macrophages in regulating fibroblast phenotype and the ECM during tendon growth.

Summary:. Aphallia is an exceedingly rare congenital malformation. The condition is the result of a sporadic anatomic anomaly during fetal development in a 46, XY male patient with otherwise normal functioning testes and male sexual hormone metabolism. Neophallus reconstruction using the De Castro phalloplasty technique is currently the most accepted treatment modality for this condition. However, most case reports in the literature do not use tissue expansion. To achieve a larger neophallus and possibly decrease the need for secondary phalloplasty postpuberty, tissue expansion should be a standardized adjunct to the De Castro procedure in the management of all patients with congenital aphallia.

Summary:. Ectopia cordis is a rare congenital condition resulting in extrathoracic positioning of the heart. The severity of presentation may vary with partial or complete displacement through sternal or diaphragmatic defects. Operative management is typically required, but due to the rarity of the condition, no standard exists for optimal closure. Reconstruction techniques can include compound local flap placement including pectoralis major, rectus abdominis, or latissimus dorsi flaps as well as synthetic material placement, autologous bone, and cartilage grafts to correct sternal deformity. This case report outlines the successful utilization of bilateral composite pectoralis major and rectus abdominal musculocutaneous flaps for complex staged closure of a sternal wound after creation of a cavopulmonary anastomosis in a 5-year-old patient with concomitant single-ventricle congenital heart disease. This single-staged closure after cardiac repair was performed without intra- or postoperative complications, and the patient demonstrated satisfactory healing with stable cardiac coverage at follow-up visit. This technique may present as an effective approach in complex sternal wound closure in patients with ectopia cordis.

Summary:. Constriction ring syndrome is a rare congenital condition characterized by the formation of fibrous amniotic bands, which can result in limb or digit deformation, malformation, or autoamputation. Surgical intervention is necessary for patients with progressive or severe forms of constriction banding, but the timing and operative approach vary widely. Here, the authors present a case report detailing the successful removal of multiple congenital constriction bands (CBs), uniquely affecting the distal ankle and foot in an infant meeting Patterson type-2 criteria. This type is characterized by CBs resulting in distal deformation with or without swelling. In this case, urgent intervention was prompted by concerns of vascular compromise, and amputation was considered due to the severity of the banding. However, the authors advocated for a staged approach, with the aim of preserving the patient’s limb. A series of three separate procedures tailored to the patient’s banding pattern and subsequent tissue complications were required to achieve restoration of ankle and foot functions, as well as satisfactory cosmesis. This case report underscores the importance of a customized surgical approach in addressing complex CBs and emphasizes the need for proactive consideration of salvage interventions by surgeons.

Summary:. Frontosphenoidal craniosynostosis (FSC) is a rare premature fusion of the frontosphenoidal suture that results in anterior plagiocephaly. When associated with severe cranial deformity, surgical treatment is beneficial. All previously reported cases of FSC correction have utilized fronto-orbital remodeling and advancement to achieve improved anatomy and increased intracranial volume. For patients with isolated synostosis deformities, we believe that distraction osteogenesis can be a viable option, with the additional benefit of quicker operating time, shorter hospital stays, and less irregularity in final head contour. This case illustrates the feasibility of using distraction osteogenesis in the management of FSC.

Summary:. Management of mandibular fractures often involves the use of maxillomandibular fixation (MMF) to attain immobility of the fractured segments. This can be used as a primary treatment modality or as an adjunct in fracture management. This technique, however, has its drawbacks due to the great burden of care imposed on patients. In the following case, fixation of a pediatric open mandibular body fracture was attained without the use of MMF, and bone union was achieved. Due to age, safety concerns, long-distance travel, and parent’s preference, the routine management of this type of fracture with MMF using piriform aperture drop wires and circummandibular wires was not done. Instead, the fracture was reduced, and an intraoral mandibular impression was taken in the operating room, which was used to create a stone model. A 2-mm acrylic splint was designed and fabricated from the stone model, and two circummandibular wires were placed. The wires were tightened over the acrylic splint to achieve stabilization of the mandibular reduction. At 4 weeks postoperatively, the splint was removed, and the patient was maintained on a soft diet. At 6 weeks, bone union was appreciated clinically by immobility of the mandibular segments, and the patient was advanced to a regular diet. Occlusion was corrected to premorbid state by clinical findings and 6 months postoperative imaging. This technique represents an effective approach in managing pediatric mandibular fractures when MMF cannot be used.

Background:. The whistle deformity, a deficiency of tissue in the central upper lip, is a consequential outcome of primary cleft lip repair. Among multiple described reconstructive options, the wide-hinged island swing transposition labial enhancement (WHISTLE) flap procedure by Grewal et al has been shown to be a reliable technique that restores the continuity of the orbicularis oris muscle and creates a more natural appearing tubercle and central lip element. This article aims to refine the WHISTLE flap procedure with the addition of tailored mucomuscular flaps and an upper lip-lengthening mucosal Z-plasty. Methods:. A total of 11 patients with a whistle deformity were examined. All underwent the WHISTLE flap procedure with tailored mucomuscular flaps and a mucosal Z-plasty. The patients were followed for a period of from 6 to 51.5 months. Pre- and postoperative photographs were used for objective outcome comparison. Results:. From 2018 to 2023, a total of 11 patients with a whistle deformity were included in the final cohort, comprised four bilateral and seven unilateral cleft lips. Ten cases (90.1%) resulted in satisfactory postoperative cosmetic appearance and did not require further interventions. A single patient with a significant preoperative discrepancy between the upper and lower lip volumes had a postoperative residual deformity. None of the patients demonstrated any functional deficits associated with the procedure. Conclusions:. The WHISTLE flap procedure with the proposed individual tailoring of the mucomuscular flap and Z-plasty for mucosal scar lengthening has excellent cosmetic outcomes and can be considered as the primary treatment modality in most patients with a whistle deformity.

Articular cartilage has a limited capacity to heal itself and thus focal defects often result in the development of osteoarthritis. Current cartilage tissue engineering strategies seek to regenerate injured tissue by creating scaffolds that aim to mimic the unique structure and composition of native articular cartilage. Decellularization is a novel strategy that aims to preserve the bioactive factors and 3D biophysical environment of the native extracellular matrix while removing potentially immunogenic factors. The purpose of this study was to develop a procedure that can enable decellularization and recellularization of intact articular cartilage matrix. Full-thickness porcine articular cartilage plugs were decellularized with a series of freeze-thaw cycles and 0.1% (w/v) sodium dodecyl sulfate detergent cycles. Chondroitinase ABC (ChABC) was applied before the detergent cycles to digest glycosaminoglycans in order to enhance donor chondrocyte removal and seeded cell migration. Porcine synovium-derived mesenchymal stem cells were seeded onto the decellularized cartilage scaffolds and cultured for up to 28 days. The optimized decellularization protocol removed 94% of native DNA per sample wet weight, while collagen content and alignment were preserved. Glycosaminoglycan depletion prior to the detergent cycles increased removal of nuclear material. Seeded cells infiltrated up to 100 μm into the cartilage deep zone after 28 days in culture. ChABC treatment enhances decellularization of the relatively dense, impermeable articular cartilage by reducing glycosaminoglycan content. ChABC treatment did not appear to affect cell migration during recellularization under static, in vitro culture, highlighting the need for more dynamic seeding methods.