title: Unexpected radiographic lucency following grafting of bone defects with calcium sulfate/tricalcium phosphate bone substitute.
abstract: OBJECTIVE
  To report the development of unexpected radiographic lucency (URL) corresponding to the use of a commercially available calcium sulfate/tricalcium phosphate composite used to treat benign osseous lesions.
  
  
  METHODS
  This is a retrospective comparative study of patients with and without URL after treatment with curettage and grafting with calcium sulfate/tricalcium phosphate. The charts of 87 patients meeting the inclusion criteria were reviewed for demographic, clinical, and radiographic data. The group with URL was compared to those with more typical patterns of graft incorporation.
  
  
  RESULTS
  Thirteen of 87 cases (15%) showed URL. There was no difference with respect to the pathologic subtype, anatomic location, or specific bone for the presence of URL. Of patients with URL, one (7.7%) required reoperation and regrafting, whereas among patients without URL, five (6.7%) had clinical complications, with one requiring reoperation and regrafting, and one requiring radiofrequency ablation.
  
  
  CONCLUSIONS
  The majority of patients treated with calcium sulfate/tricalcium phosphate cementing after curettage of low-grade bone lesions go on to uneventful healing in our series. In a minority of patients, URL occurs in lieu of the more typical pattern of centripetal incorporation. However, there is no increase in complications associated with URL. Based on these findings, patients should be informed of the possibility of this risk, although there appears to be little risk of clinically relevant adverse consequences. Physicians should be aware of this complication in order to avoid mistaking it for recurrence of the primary lesion.
authors.affiliation: Department of Orthopedic Surgery, State University New York Upstate Medical University, Syracuse, NY, USA.
authors.forename: Darryl A
authors.initials: DA
authors.lastname: Auston
authors.forename: Matthew
authors.initials: M
authors.lastname: Feibert
authors.forename: Tina
authors.initials: T
authors.lastname: Craig
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Damron
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001672:Biocompatible Materials / Q000627:therapeutic use; D001847:Bone Diseases / Q000000981:diagnostic imaging* / Q000601:surgery*; D018786:Bone Substitutes / Q000627:therapeutic use*; D016025:Bone Transplantation / Q000379:methods*; D002130:Calcium Phosphates / Q000627:therapeutic use*; D002133:Calcium Sulfate / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D002130:Calcium Phosphates; C018392:tricalcium phosphate; D002133:Calcium Sulfate