Effects of Neurofibromatosis Type 1 on Pseudoarthrosis and the Forensic Implications

Abstract

Pseudoarthrosis is the presentation of false joints or non-union, primarily in long bones. While pseudoarthrosis most often presents as the lack of union between parts of a fractured or broken bone, it is also suspected that pseudoarthrosis results from a congenital disorder of unknown origin. While the etiology is unclear, there is an association with a congenital defect in neurofibromatosis type 1 gene through the neurofibromin protein. This defect occurs during the germ line mutation of conception and is often identified during early childhood. Pseudoarthrosis is more often difficult to detect in adults as it is frequently corrected during childhood. Germ line defects along the neurofibromin protein often result in a lack of communication from the reticular activating system (RAS) molecular signaling, which, in turn, impacts skeletal osteon production. Consequently, osseous lesions may develop and lead to a lack of cellular control over osteoblast signaling in the long bones of the skeleton. Understanding the origins of congenital pseudoarthrosis and its relationship with neurofibromatosis type 1 could lead to a better understanding of both conditions. Understanding these conditions can be useful for interpreting forensic contexts. These contexts include having the histological knowledge of osteology in these diseases for identification purposes. Given that both neurofibromatosis type 1 and pseudoarthrosis are uncommon conditions, their presence may aid forensic practitioners in determining cause of death or identification of the individual. This paper reviews new advances towards understanding the root cause of pseudoarthrosis.