An Assessment of Fate of CHA Blocks Used in the Cystic Lesions of Bone.

ABSTRACT

Background: The calcium phosphate system and in particular hydroxyapatite (CHA), has been the subject of intensive investigation. Although coralline hydroxyapatite is not inherently as strong as trabecular bone and does not exhibit plastic properties owing to the absence of a collagen matrix, with subsequent growth of native bone, it has been shown to become stronger but less stiff than autogenous graft material. Method: Thirty six cases of cystic lesions of long bones were curretted and filled with CHA blocks with or without autogenous cancellous bone chips between 2013 to 2014 with follow up duration ranging from 12 to 24 months. Filling by CHA blocks, mixing with autogenous bone grafts was done in osteoclastoma and fibrous dysplasia cases, while only CHA block filling was done in solitary bone cyst, aneurysmal bone cyst and fibroma cases. In all the cases, the diagnosis was made on the basis of clinical, radiological and histopathological examination. Both with and without pathological fractures cystic lesions were taken. Results: In the present study, 11 cases had pathological fracture. In our series, maximum cases were of osteoclastoma. Most of the cases were associated with pathological fracture. The pathological fractures united from 20-30 weeks time, Radiologically, the density of CHA blocks increased with the lapse of time. In our series, the longest follow up period was about 24 months and the shortest was of 12 months duration. 20 patients had excellent results with full functional, anatomical restoration without any pain and radiograph shows no recurrence, with healing of pathological fracture. While 2 patients had poor results they were not able to do activities of daily living, had pain and delayed healing. Conclusion: The CHA has favourable clinical result because of less adverse effects, biocompatibility to the tissue of the body, ease of manufacture, production and shape adjustment. Therefore, it is strongly suggested as a useful bone substitute.In our limited experience with coralline hydroxyapatite bone graft substitutes, we have encountered no significant complications related to implant themselves.