title: Overlapping allograft for primary or salvage bone tumor reconstruction.
abstract: BACKGROUND
  Compared with end-to-end allograft coaptation, overlapping allograft offer a superior union rate by increasing the contact area. However, reports on overlapping allograft are scarce. Therefore, we attempted to confirm the usefulness of this technique either after primary tumor resection or in salvaging a failed reconstruction.
  
  
  METHODS
  We analyzed the outcome of 35 overlapping allografts reconstructions. Indications were primary reconstruction of a skeletal defect (n = 19) and salvage of a failed reconstruction (n = 16). Graft survival, union rate, and time to union were evaluated as a function of clinical variables such as age, use of chemotherapy, type of junction, method of fixation, length of overlapped bone, and method of overlapping.
  
  
  RESULTS
  All 35 overlapping allografts showed union at a mean of 5.6 months (range, 3-14 months). One allograft was removed with local recurrence at 19 months post-operatively. Average length of overlapped bone was 3.5 cm (range, 1.4-6.5 cm). Patient age <15-years (P = 0.001) and circumferential overlapping (P = 0.011) shortened the time to union.
  
  
  CONCLUSIONS
  In terms of graft failure rate, union rate, and time to union, overlapping allograft is an excellent technique, which overcomes the limitations of end-to-end fixation.
authors.affiliation: Department of Orthopedic Surgery, Korea Cancer Center Hospital, Seoul, Korea.
authors.forename: Dae-Geun
authors.initials: DG
authors.lastname: Jeon
authors.forename: Won Seok
authors.initials: WS
authors.lastname: Song
authors.forename: Wan Hyeong
authors.initials: WH
authors.lastname: Cho
authors.forename: Chang-Bae
authors.initials: CB
authors.lastname: Kong
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Cho
authors.forename: Sung Woo
authors.initials: SW
authors.lastname: Choi
authors.forename: Soo-Yong
authors.initials: SY
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D064591:Allografts; D001859:Bone Neoplasms / Q000601:surgery*; D016025:Bone Transplantation / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019651:Plastic Surgery Procedures / Q000379:methods*; D016879:Salvage Therapy
keywords: allograft; bone tumor; overlapping