Some of the risks with open biopsy can be avoided by fine-needle aspiration biopsy. The diagnostic contribution of radiologic findings has not been systematically studied.We retrospectively analyzed the validity of combined radiology and fine-needle aspiration cytology for the diagnosis of bone lesions in a consecutive series of 370 patients. The treatment diagnosis was based solely on radiology and cytology in 234 cases, whereas in 136 cases histopathology was also applied.Comparison of radiology and cytology showed diagnostic compliance in 256 cases (69%) and non-compliance in 101 (28%). 13 (3%) cases failed to yield diagnostic material for cytology. Among the 256 compliant cases, the diagnostic error rate was 1% (2 were falsely benign), whereas the corresponding rate was 17% among the 101 non-compliant cases. In the latter group, 36 cases yielded only normal cells at aspiration, out of which 20 proved to have a neoplastic lesion (8 metastases, 12 benign). The overall sensitivity of cytology alone in recognizing malignancy was 90%. The specificity was 95%. Given a malignant or benign diagnosis, the positive predictive value was 97% and the negative predictive value was 84%.Our study suggests that a simple approach based on conventional radiography and fine-needle aspiration cytology offers a valid means of diagnosing bone lesions. Provided there is compliance between radiology and cytology, the risk of false diagnosis is around 1%.
In 14 adult rabbits the middle third of the ulna was resected bilaterally followed by reimplantation of resected bone after autoclaving on one side and transplantation of allogeneic bone on the other. In 7 animals the bilateral implants were supplemented with allogeneic bone matrix. The reconstructions were studied in vivo by serial radiography, scintigraphy, and bone mineral determination. The animals were killed at 16 weeks, and the ulnar reconstructions further studied by high resolution radiography, 45Ca autoradiography, and histology. In both types of nonsupplemented reconstructions, new bone formation was poor; nonunion occurred in three out of seven autoclaved reimplants and in five out of seven allogeneic transplants. Supplemented with allogeneic bone matrix, both types of reconstructions exhibited abundant new bone formation and complete incorporation of all implants.Enhancement of new bone formation is probably more important than the type of nonviable bone graft chosen for reconstruction of large skeletal defects.
Substance P (SP) has been shown in vitro to stimulate both formation and resorption of bone. This seemingly contradictory observation could be explained by in vivo variations in skeletal loading and rate of bone turnover, features which may be explored during different phases of fracture healing. In 50 SD rats, the right tibia was fractured and fixed with an intramedullary pin in straight alignment and in anterior angulation resulting in a convex and concave side under different load. Fracture repair was assessed by radiography, histology, and semi-quantitative immunohistochemistry of SP nerve fiber occurrence at days 7, 21, 35, 56, and 84 post-fracture. During regeneration, days 7-35, abundant SP-nerve ingrowth was observed in the fracture callus reaching a side-symmetrical peak at day 21 in straight fractures. In angulated fractures, the SP peak was also observed at day 21 on the concave loaded side, but not until day 35 on the convex unloaded side. Each SP-peak coincided with cortical bridging. During remodeling, days 35-84, a side-symmetrical disappearance of SP-positive fibers was seen in straight fractures. The same pattern was seen on the concave loaded side of angulated fractures. However, on the convex unloaded side, where resorption now took place, SP-fibers remained until the end of the experiment. Our study suggests that neuronal SP during bone regeneration has a stimulatory role on bone formation, while during remodeling increased SP fiber density in unloaded areas may be related to bone resorption.
