Differentiated adipose-derived stem cell cocultures for bone regeneration in polymer scaffolds in vivo.

Critical-sized bone defects can lead to significant morbidity, and interventions are limited by the availability and donor-site morbidity of bone grafts. Polymer scaffolds seeded with cells have been explored to replace bone grafts. Adipose-derived stem cells have shown great promise for vascularization and osteogenesis of these constructs, and cocultures of differentiated stem cells are being explored to augment vessel and bone formation. Adipose-derived stem cells were differentiated into endothelial cells and osteoblasts, and in vitro studies showed increased proliferation of cocultured cells compared with undifferentiated adipose-derived stem cells and monocultures of endothelial cells and osteoblasts. The cells were seeded into polylactic acid gas-plasma-treated scaffolds as cocultures and monocultures and then implanted into critical-sized rat calvarial defects. The cocultures were in a 1:1 osteoblast to endothelial cell ratio. The increase in proliferation seen by the cocultured cells in vitro did not translate to increased vascularization and osteogenesis in vivo. In vivo, there were trends of increased vascularization in the endothelial cell group and increased osteogenesis in the osteoblast and endothelial monoculture groups, but no increase was seen in the coculture group compared with the undifferentiated adipose-derived stem cells. Endothelial cells enhance vascularization and osteoblast and endothelial cell monocultures enhance bone formation in the polymer scaffold. Predifferentiation of adipose-derived stem cells is promising for improving vascularization and osteogenesis in polymer scaffolds but requires future evaluation of coculture ratios to fully characterize this response.

Epidermal Inclusion Cyst Formation: Late Complication of Carpal Tunnel Release.

Background Epidermal inclusion cysts (EIC) are epidermally lined, keratin containing cysts which occur when keratinizing epithelium becomes imbedded in deeper subcutaneous tissue, usually following penetrating trauma, or, rarely, surgery. We describe a case of an EIC presenting as a late complication following open carpal tunnel release (CTR). Case Description A 64-year-old woman with a history of left open CTR 17 years prior presented to our institution with unprovoked left palmar pain, swelling, and fluctuance. Computed tomography imaging confirmed the presence of a multiloculated abscess involving the hypothenar musculature. The abscess developed at the site of a small, pre-existing, asymptomatic mass that the patient recalls developed within months of CTR surgery. She was initially treated with antibiotics and bedside incision and drainage, but required further operative exploration in the setting of persistent erythema and drainage. An inflamed cystic structure consistent with an infected EIC was identified and completely excised. Her wound healed by secondary intention. Her postoperative course was uncomplicated. Pathology confirmed a diagnosis of EIC. Literature Review Only one other case report was found in which the patient presented within 2 years following CTR surgery with what was later confirmed to be an EIC and recurrent median nerve compression symptoms. Clinical Relevance To prevent a delay in definitive surgical care, EIC rupture and subsequent infection should be considered in the differential diagnosis when evaluating patients with a history of prior hand surgery who are presenting with an unprovoked hand abscess, as incision and drainage alone will not adequately treat an EIC.

Abdominal implantation of testicles in the management of intractable testicular pain in Fournier gangrene.

Fournier gangrene (FG) is a necrotizing soft tissue infection involving the superficial and fascial planes of the perineum. In many cases of FG, debridement of the scrotum is necessary, leaving definitive management of the exposed testicles a significant surgical challenge. Frequent incidental trauma to the testicles can cause severe pain, especially in laborers. Practical surgical solutions are few and not well detailed. Various options exist, including creating a neoscrotum with adjacent thigh tissue, split-thickness skin grafts (STSGs), or even creating a subcutaneous thigh pocket. We describe a case of abdominal implantation of bilateral testicles for persistent testicular pain in a case where STSGs did not provide adequate protection, adjacent thigh skin was not available for creation of a neoscrotum, and significant cord contracture occurred. We detail the advantages and disadvantages of the commonly described techniques, including this approach, and how in select individuals this may be a suitable alternative.

Effect of adipose tissue-derived osteogenic and endothelial cells on bone allograft osteogenesis and vascularization in critical-sized calvarial defects.

The use of processed bone allograft to repair large osseous defects of the skull has been limited, given that it lacks the osteogenic cellularity and intrinsic vascular supply which are essential elements for successful graft healing and, at the same time, the areas to be targeted through tissue-engineering applications. In this study, we investigated the effect of predifferentiated rat adipose tissue-derived osteoblastic cells (OBs) and endothelial cells (ECs) on calvarial bone allograft healing and vascularization using an orthotopic critical-sized calvarial defect model. For this purpose, thirty-seven 8 mm critical calvarial defects in Lewis rats were treated with bone allografts seeded with no cells, undifferentiated adipose tissue-derived stem cells (ASC), OBs, ECs, and OBs and ECs simultaneously. After 8 weeks, the bone volume and mineral density were calculated using microcomputed tomography and the microvessel formation using immunohistochemical staining and imaging software. The amount of bone within the 8 mm defect was significantly higher for the allografts treated with ECs compared with the allografts treated with OBs (p=0.05) and simultaneously with the two cell lineages (p=0.02). There were no significant differences in bone formation between the latter two groups and the control groups (allografts treated with no cells and undifferentiated ASC). There were no significant differences in bone mineral density among the groups. The amount of microvessels was significantly higher in the group treated with ECs relative to all groups (p=< 0.05). Our results show that the implantation of ASC-derived ECs improves the vascularization of calvarial bone allografts at 8 weeks after treatment. This cell-based vascularization strategy can be used to improve the paucity of perfusion in allogenic bone implants. However, in this study, the treatment of allografts with OBs alone or in combination with ECs did not support bone formation or vascularization.

Traditional Lower Blepharoplasty: Is Additional Support Necessary? A 30-Year Review.

BACKGROUND: Several refinements have been made in lower eyelid rejuvenation, and there is now strong belief that the traditional approach places too little emphasis on lower eyelid support. The purpose of this study was to retrospectively review the 30-year experience of the senior author (J.A.F.) performing primary lower blepharoplasty by the traditional approach and to determine the complication rate when lower lid-tightening procedures were not performed concomitantly. METHODS: A retrospective chart review of all traditional blepharoplasties performed by the senior author over the past 30 years was performed. The traditional approach was performed through an external, subciliary incision. Concomitant lower lid-tightening procedures were not performed. The authors determined the complication rate of the procedure, such as symptomatic lower eyelid malposition and chemosis. RESULTS: A total of 3014 patients underwent traditional lower blepharoplasties and, after applying the exclusion criteria, 2007 patients were studied. A postoperative complication was defined as the development of either chemosis or symptomatic lower eyelid malposition. Chemosis developed in only 1.2 percent of the patients (24 of 2007). Eight of the 2007 patients (0.4 percent) developed symptomatic lower eyelid malposition. CONCLUSIONS: This study proves that when performed meticulously and precisely, traditional lower blepharoplasty is safe and effective. Correction of preoperatively diagnosed lower lid laxity is essential; however, when lower eyelid tone is adequate, the authors believe that the routine addition of a tightening procedure for support or the routine use of combined internal and external approaches is unnecessary. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.