title: Repair of segmental long-bone defects by stem cell concentrate augmented scaffolds: a clinical and positron emission tomography--computed tomography analysis.
abstract: OBJECTIVE
  Treating segmental long-bone defects remains a major challenge. For defects >3 cm, segmental transport represents the gold standard, even though the method is time consuming and afflicted with several complications. The aim of this study was to evaluate healing of such defects after grafting an osteogenic scaffold previously seeded with stem cell concentrate.
  
  
  METHODS
  We evaluated five patients with segmental long-bone defects (3-14 cm) treated with bone marrow aspirate concentrates (BMAC) seeded onto a bovine xenogenous scaffold. The healing process was monitored by X-rays and positron emission tomography-computed tomography (PET-CT) three months after surgery.
  
  
  RESULTS
  Centrifugation led to a concentration of leukocytes by factor 8.1 ± 7.5. Full weight bearing was achieved 11.3 ± 5.0 weeks after surgery. PET analysis showed an increased influx of fluoride by factor 8.3 ± 6.4 compared with the contralateral side (p < 0.01). Bone density in the cortical area was 75 ± 16 % of the contralateral side (p < 0.03). The patient with the largest defect sustained an implant failure in the distal femur and finally accomplished therapy by segmental transport. He also had the lowest uptake of fluoride of the patient collective (2.2-fold increase).
  
  
  CONCLUSIONS
  Stem cell concentrates can be an alternative to segmental bone transport. Further studies are needed to compare this method with autologous bone grafting and segmental transport.
authors.affiliation: Trauma Department, Hannover Medical School (MHH), Carl-Neuberg-Straße 1, 30625, Hannover, Germany, petri.maximilian@mh-hannover.de.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Petri
authors.forename: Ali
authors.initials: A
authors.lastname: Namazian
authors.forename: Florian
authors.initials: F
authors.lastname: Wilke
authors.forename: Max
authors.initials: M
authors.lastname: Ettinger
authors.forename: Timo
authors.initials: T
authors.lastname: Stübig
authors.forename: Stephan
authors.initials: S
authors.lastname: Brand
authors.forename: Frank
authors.initials: F
authors.lastname: Bengel
authors.forename: Christian
authors.initials: C
authors.lastname: Krettek
authors.forename: Georg
authors.initials: G
authors.lastname: Berding
authors.forename: Michael
authors.initials: M
authors.lastname: Jagodzinski
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D001847:Bone Diseases / Q000628:therapy*; D016025:Bone Transplantation / Q000379:methods*; D002417:Cattle; D005269:Femur / Q000000981:diagnostic imaging / Q000601:surgery*; D005459:Fluorides; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010012:Osteogenesis / Q000502:physiology; D049268:Positron-Emission Tomography; D011859:Radiography; D012189:Retrospective Studies; D033581:Stem Cell Transplantation / Q000379:methods*; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014945:Wound Healing / Q000502:physiology; D055815:Young Adult
chemical_list: D005459:Fluorides