Craniofacial and Long Bone Development in the Context of Distraction Osteogenesis.

BACKGROUND: Bone retains regenerative potential into adulthood, and surgeons harness this plasticity during distraction osteogenesis. The underlying biology governing bone development, repair, and regeneration is divergent between the craniofacial and appendicular skeleton. Each type of bone formation is characterized by unique molecular signaling and cellular behavior. Recent discoveries have elucidated the cellular and genetic processes underlying skeletal development and regeneration, providing an opportunity to couple biological and clinical knowledge to improve patient care. METHODS: A comprehensive literature review of basic and clinical literature regarding craniofacial and long bone development, regeneration, and distraction osteogenesis was performed. RESULTS: The current understanding in craniofacial and long bone development and regeneration is discussed, and clinical considerations for the respective distraction osteogenesis procedures are presented. CONCLUSIONS: Distraction osteogenesis is a powerful tool to regenerate bone and thus address a number of craniofacial and appendicular skeletal deficiencies. The molecular mechanisms underlying bone regeneration, however, remain elusive. Recent work has determined that embryologic morphogen gradients constitute important signals during regeneration. In addition, striking discoveries have illuminated the cellular processes underlying mandibular regeneration during distraction osteogenesis, showing that skeletal stem cells reactivate embryologic neural crest transcriptomic processes to carry out bone formation during regeneration. Furthermore, innovative adjuvant therapies to complement distraction osteogenesis use biological processes active in embryogenesis and regeneration. Additional research is needed to further characterize the underlying cellular mechanisms responsible for improved bone formation through adjuvant therapies and the role skeletal stem cells play during regeneration.

Morphometric analysis of the patterns of calcaneal facets for the talus in Serbian population.

Literature describes different patterns of calcaneal facets for the talus in terms of whether some calcaneal facets are connected or separated from each other or completely absent. The aim of this study was to establish the patterns of calcaneal facets for the talus, to calculate their total area, and to analyse the data with respect to gender. The study involved 59 calcanei which were photographed. The patterns of calcaneal facets noted in this study were compared with the patterns from the literature. ImageJ program was used to measure different parameters on calcanei. The pattern 1 was the most commonly found in the study sample (45.76%), then the pattern 2 (40.68%), and finally the pattern 3 (13.56%). That order of frequencies is the same in both sexes. The patterns 1 and 2 have a larger contact surface for the talus in comparison to the pattern 3. Male bones have a larger contact surface for the talus than female bones. The sum of the pattern 1 and pattern 3 frequencies was high. Knowing the frequency of different patterns of calcaneal facets for the talus in a certain population is important for orthopaedic surgeons when performing foot osteotomy.

Surgical Strategies for Chordoma.

Chordomas are rare tumors of the axial skeleton whose slow growth belies a relentless tumor with a propensity for recurrence and late metastasis. Local control remains an issue with chordoma in spite of aggressive operative management. High local failure rates have led to the exploration of alternative methods of treatment. Radiation continues to gain acceptance as an adjuvant to surgery and, in some cases, as a standalone treatment. However, the use of radiation remains controversial, and operative management remains the standard of care in spite of relatively high morbidity.