The micro and ultrastructural anatomy of bone spicules found in the osteochondral junction of bovine patellae with early joint degeneration.

The structural changes in the tissues of the osteochondral junction are a topic of interest, especially considering how bone changes are involved in the initiation and progression of osteoarthritis (OA). Our research group has previously demonstrated that at the cement line boundary between the zone of calcified cartilage (ZCC) and the subchondral bone, in mature bovine patellae with early OA, there are numerous bone spicules that have emerged from the underlying bone. These spicules contain a central vascular canal and a bone cuff. In this study, we use high-resolution differential interference contrast optical microscopy and scanning electron microscopy to compare the cartilage-bone junction of three groups of mature bovine patellae showing healthy to mild to moderately degenerate cartilage. The ZCC and bone junction was carefully examined to estimate the frequency of marrow spaces, bone spicules and fully formed bone bulges. The results reveal that bone spicules are associated with all grades of cartilage tissue studied, with the most occurring in the intermediate stages of tissue health. The micro and ultrastructure of the bone spicule are consistent with that of an osteon, especially those found in compression zones in long bones. Also considering the coexistence of marrow spaces and fully formed bone, this study suggests that these bone spicules arise similar to the formation of osteons in the bone remodelling process. The significance of this conclusion is in the way researchers approach the bone formation issue in the early degenerative joint. Instead of endochondral ossification, we propose that bone formation in OA is more akin to a combination of primary bone remodelling and de novo bone formation.

Self-Reflective Meaning Making in Troubled Times: Change in Self-Identity After Traumatic Brain Injury.

Our aim with this article is to clarify the concept of change in self-identity following traumatic brain injury (TBI). We used concept analysis methodology-predominantly concept clarification. We identified 110 articles using a systematic literature search, and used critical appraisal, content analysis, and analytical questioning to explore attributes and boundaries. A reported change in self-identity is the ultimate expression of a variety of cognitive, psychological, and social sequelae of TBI. We present an integrative model of this process, identifying three potential levels of change: (a) component parts (egocentric self, sociocentric self, and "identity as shared with others"); (b) integral processes (self-awareness and expression via meaningful occupation and narratives); and (c) whole-system disruption. Change in self-identity after TBI is a highly individualistic process. The driver of this process is "self-reflective meaning making," giving a purpose and direction in life, providing motivation and goals for future behavior.