title: Bone marrow aspirate concentrate and platelet-rich plasma enhanced bone healing in distraction osteogenesis of the tibia.
abstract: BACKGROUND
  During lower limb lengthening, poor bone regeneration is a devastating complication. Several local or systemic applications have been used to promote osteogenesis, and biologic stimulations are gaining attention, but their utility has not been proven in this setting.
  
  
  OBJECTIVE
  In patients undergoing bilateral tibial lengthening, we compared those receiving an osteotomy site injection of autologous bone marrow aspirate concentrate (BMAC) plus platelet-rich plasma (PRP) with those not receiving such an injection in terms of external fixator index (time in external fixation divided by amount of lengthening), full weightbearing index (time until a patient was permitted to do full weightbearing divided by amount of lengthening), four cortical healing indexes (time until each cortical union divided by amount of lengthening), and callus shape and type.
  
  
  METHODS
  Twenty-two patients (44 tibias) undergoing bilateral tibial lengthening enrolled in this randomized trial. Two patients were excluded, one due to insufficient radiographic evaluation and one who was lost to followup, leaving 20 patients (40 segments) for inclusion. Ten patients (20 segments) received BMAC combined with PRP injection (treatment group) and 10 patients (20 segments) received no injection (control group). All patients underwent stature lengthening for familial short stature with the lengthening over nail technique. Autologous BMAC combined with PRP was injected at the tibial osteotomy site at the end of the index surgery. Mean distraction rates were similar between groups (0.75 mm/day in the treatment group versus 0.72 mm/day in the control group; p = 0.24). Full weightbearing was permitted when we observed radiographic evidence of healing at two cortices; this assessment was made by the surgeon who was blinded to the treatment each patient received. Minimum followup was 24 months (mean, 28 months; range, 24-34 months).
  
  
  RESULTS
  There was no difference in mean external fixator index between groups. However, mean cortical healing indexes (anterior/posterior/medial/lateral) were 1.14/0.81/0.96/0.88 months/cm in the treatment group and 1.47/1.26/1.42/1.22 months/cm in the control group (all p < 0.001), showing faster healing in the treatment group at each cortex. Full weightbearing was permitted earlier in the treatment group than in the control group (index: 0.99 months/cm and 1.38 months/cm, respectively, p < 0.001). Callus shape and type were not different between groups.
  
  
  CONCLUSIONS
  Autologous BMAC combined with PRP injection at the osteotomy site helped improve bone healing in distraction osteogenesis of the tibia, although the effect size was small.
  
  
  METHODS
  Level I, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: Department of Orthopaedic Surgery, Severance Hospital, College of Medicine, Yonsei University, 134 Sinchondong, CPO Box 8044, Seoul, Republic of Korea, orthopaedee@naver.com.
authors.forename: Dong Hoon
authors.initials: DH
authors.lastname: Lee
authors.forename: Keun Jung
authors.initials: KJ
authors.lastname: Ryu
authors.forename: Jin Woo
authors.initials: JW
authors.lastname: Kim
authors.forename: Kyung Chung
authors.initials: KC
authors.lastname: Kang
authors.forename: Young Rak
authors.initials: YR
authors.lastname: Choi
mesh_terms: D000293:Adolescent; D000328:Adult; D001696:Biomechanical Phenomena; D016026:Bone Marrow Transplantation / Q000379:methods*; D001861:Bone Regeneration; D016267:External Fixators; D005260:Female; D005592:Fracture Fixation / Q000295:instrumentation; D017102:Fracture Healing; D006801:Humans; D007267:Injections; D008297:Male; D019857:Osteogenesis, Distraction / Q000009:adverse effects / Q000379:methods*; D010027:Osteotomy; D053657:Platelet-Rich Plasma; D011859:Radiography; D056910:Republic of Korea; D013977:Tibia / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D014182:Transplantation, Autologous; D016896:Treatment Outcome; D016474:Weight-Bearing; D055815:Young Adult