SummaryIdentification of human satellite cells that fulfill muscle stem cell criteria is an unmet need in regenerative medicine. This hurdle limits understanding how closely muscle stem cell properties are conserved among mice and humans and hampers translational efforts in muscle regeneration. Here, we report that PAX7 satellite cells exist at a consistent frequency of 2–4 cells/mm of fiber in muscles of the human trunk, limbs, and head. Xenotransplantation into mice of 50–70 fiber-associated, or 1,000–5,000 FACS-enriched CD56+/CD29+ human satellite cells led to stable engraftment and formation of human-derived myofibers. Human cells with characteristic PAX7, CD56, and CD29 expression patterns populated the satellite cell niche beneath the basal lamina on the periphery of regenerated fibers. After additional injury, transplanted satellite cells robustly regenerated to form hundreds of human-derived fibers. Together, these findings conclusively delineate a source of bona-fide endogenous human muscle stem cells that will aid development of clinical applications.

Pediatric obstructive sleep apnea, characterized by partial or complete obstruction of the upper airway during sleep, is associated with multiple adverse neurodevelopmental and cardiometabolic consequences. It is common in healthy children and occurs with a higher incidence among infants and children with craniofacial anomalies. Although soft-tissue hypertrophy is the most common cause, interplay between soft tissue and bone structure in children with craniofacial differences may also contribute to upper airway obstruction. Snoring and work of breathing are poor predictors of obstructive sleep apnea, and the gold standard for diagnosis is overnight polysomnography. Most healthy children respond favorably to adenotonsillectomy as first-line treatment, but 20 percent of children have obstructive sleep apnea refractory to adenotonsillectomy and may benefit from positive airway pressure, medical therapy, orthodontics, craniofacial surgery, or combined interventions. For children with impairment of facial skeletal growth or craniofacial anomalies, rapid maxillary expansion, midface distraction, and mandibular distraction have all been demonstrated to have therapeutic value and may significantly improve a child's respiratory status. This Special Topic article reviews current theories regarding the underlying pathophysiology of pediatric sleep apnea, summarizes standards for diagnosis and management, and discusses treatments in need of further investigation, including orthodontic and craniofacial interventions. To provide an overview of the spectrum of disease and treatment options available, a deliberately broad approach is taken that incorporates data for both healthy children and children with craniofacial anomalies.

Background Adult acquired buried penis syndrome may be associated with an inability to void, sexual dysfunction, and recurrent infection. Previously published classification systems rely on intraoperative findings, such as penile skin quality. Objectives The purpose of this study was to evaluate outcomes after adult acquired buried penis repair and to develop a classification system based on preoperative assessment. Methods The authors reviewed data from patients who underwent buried penis reconstruction at a single institution. Patient history and physical examination guided the development of a classification system for surgical planning. Results Of the 27 patients included, the mean age was 56 ± 15 years and mean body mass index was 49 ± 14 kg/m2. Patients were classified into 4 groups based on examination findings: (I) buried penis due to skin deficiency, iatrogenic scarring, and/or diseased penile skin (n = 3); (II) excess abdominal skin and fat (n = 6); (III) excess skin and fat with diseased penile skin (n = 16); and (IV) type III plus severe scrotal edema (n = 2). Surgical treatment (eg, excision and grafting, mons suspension, panniculectomy, translocation of testes, and/or scrotectomy) was tailored based on classification. Complications included wound breakdown (n = 3), cellulitis (n = 4), and hematoma (n = 1). Nearly all patients (96%) reported early satisfaction and improvement in their symptoms postoperatively. Conclusions Classifying patients with buried penis according to preoperative examination findings may guide surgical decision-making and preoperative counseling and allow for optimized aesthetics to enhance self-esteem and sexual well-being. Level of Evidence: 4

The combined use of the trephine ICBG technique and ropivacaine infusion catheter effectively decreased pain, shortened hospital stay, and improved cost saving compared to patients who have undergone other methods of ICBG.

Craniofacial disorders present markedly complicated problems in reconstruction because of the complex interactions of the multiple, simultaneously affected tissues. Regenerative medicine holds promise for new strategies to improve treatment of these disorders. This review addresses current areas of unmet need in craniofacial reconstruction and emphasizes how craniofacial tissues differ from their analogs elsewhere in the body. We present a problem-based approach to illustrate current treatment strategies for various craniofacial disorders, to highlight areas of need, and to suggest regenerative strategies for craniofacial bone, fat, muscle, nerve, and skin. For some tissues, current approaches offer excellent reconstructive solutions using autologous tissue or prosthetic materials. Thus, new “regenerative” approaches would need to offer major advantages in order to be adopted. In other tissues, the unmet need is great, and we suggest the greatest regenerative need is for muscle, skin, and nerve. The advent of composite facial tissue transplantation and the development of regenerative medicine are each likely to add important new paradigms to our treatment of craniofacial disorders.