Histopathologic analysis of failed vascularized fibular grafts in femoral head osteonecrosis

Abstract

Salient histopathological features in 13 failed free vascularized fibular autografts implanted for osteonecrosis of the femoral head are documented. Of particular clinical and/or biomechanical relevance are 1-2-mm-thick seams of viable lamellar bone bonded circumferentially to anatomically intact but necrotic graft cortices, which appear to preclude their revascularization and remodeling. Surrounding the grafts are 3-6-mm-thick rings of reactive bone, fused in many sites (average approximately 54%) to the osseous seams. They consist of a layer of sclerotic cortical-like bone melded with an outer layer of thickened cancellous bone. This remodeled reactive bone, largely the result of drilling, appears to buttress the grafts structurally and by inference, functionally. Operative failures in all but one case are attributed primarily to collapse of the necrotic, fractured superior subtending segment of the graft and of the subchondral plate secondary to size and progression of the osteonecrosis and superimposed osteoarthrosis. Morphological integrity of grafts elsewhere and perifibular reactive sclerotic bone remain unimpaired for up to 5 1/2 years. The salutary features of vascularized autografts would appear to give them a decided advantage over their nonvascularized counterpart.

Complication of osteo reconstruction by utilizing free vascularized fibular bone graft

“…The true relationship between the risk factors and reconstructive failure will be deviated. Histopathological analysis should be the most convincing examination but is limited by small size [101,102] . However, at least, it is clear that the postoperative steroid-use is a risk factor for the progression of osteonecrosis [103,104].…”

Failed vascularized fibular graft in treatment of osteonecrosis of the femoral head. A histopathological analysis

“…Differently from the results of our study, these Authors stated that their six osteonecrotic femoral heads failed as a result of incorrect placement of the graft, which did not provide mechanical support for the subchondral plate. our observations were based on a larger number of patients (15) than were included in the studies of Carter et al (24) and González Della Valle et al (25). González Della Valle et al (25) and Beris et al (26) believed that precise placement of the bone graft supporting the subchondral plate is the most important factor; our results indicate that remodeling and removal of dead tissue in zone 1 also removes graft substance and therefore support for the articular cartilage.…”

“…Published studies detailing the histological features of autogenous free vascularized fibular grafts in femoral head on are limited. Carter et al (24) analyzed 13 retrieved femoral heads, which were divided into six transaxial segments (from the base to the articular surface). their patients were similar to our group of patients in median age and range of the interval between fibular grafting and conversion to tHA.…”

Assessment of the incorporation of revascularized fibula grafts used for mandibular reconstruction with F-18-PET

“…Experimental studies have shown that successful incorporation of revascularized bone grafts depends on sufficient blood supply and osteocyte survival (27,40). Grafts having failed to be incorporated were histologically characterized by osteonecrosis, going along with reduced de novo osteogenesis (9,25). Osteonecrosis may even occur despite patency of the microvascular anastomosis (9).…”

“…Grafts having failed to be incorporated were histologically characterized by osteonecrosis, going along with reduced de novo osteogenesis (9,25). Osteonecrosis may even occur despite patency of the microvascular anastomosis (9). Since F-18-PET allows to quantitate the transport of fluoride from plasma into bone, it is hypothesized…”