title: Articular cartilage regeneration with autologous peripheral blood progenitor cells and hyaluronic acid after arthroscopic subchondral drilling: a report of 5 cases with histology.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the quality of articular cartilage regeneration after arthroscopic subchondral drilling followed by postoperative intraarticular injections of autologous peripheral blood progenitor cells (PBPCs) in combination with hyaluronic acid (HA).
  
  
  METHODS
  Five patients underwent second-look arthroscopy with chondral core biopsy. These 5 patients are part of a larger pilot study in which 180 patients with International Cartilage Repair Society grade III and IV lesions of the knee joint underwent arthroscopic subchondral drilling followed by postoperative intra-articular injections. Continuous passive motion was used on the operated knee 2 hours per day for 4 weeks. Partial weight bearing was observed for the first 6 to 8 weeks. Autologous PBPCs were harvested 1 week after surgery. One week after surgery, 8 mL of the harvested PBPCs in combination with 2 mL of HA was injected intra-articularly into the operated knee. The remaining PBPCs were divided into vials and cryopreserved. A total of 5 weekly intra-articular injections were given.
  
  
  RESULTS
  Second-look arthroscopy confirmed articular cartilage regeneration, and histologic sections showed features of hyaline cartilage. Apart from the minimal discomfort of PBPC harvesting and localized pain associated with the intra-articular injections, there were no other notable adverse reactions.
  
  
  CONCLUSIONS
  Articular hyaline cartilage regeneration is possible with arthroscopic subchondral drilling followed by postoperative intraarticular injections of autologous PBPCs in combination with HA.
  
  
  METHODS
  Level IV, therapeutic case series.
authors.affiliation: Kuala Lumpur Sports Medicine Centre, Kuala Lumpur, Malaysia. sportsclinic@hotmail.com
authors.forename: Khay-Yong
authors.initials: KY
authors.lastname: Saw
authors.forename: Adam
authors.initials: A
authors.lastname: Anz
authors.forename: Shahrin
authors.initials: S
authors.lastname: Merican
authors.forename: Yong-Guan
authors.initials: YG
authors.lastname: Tay
authors.forename: Kunaseegaran
authors.initials: K
authors.lastname: Ragavanaidu
authors.forename: Caroline S Y
authors.initials: CS
authors.lastname: Jee
authors.forename: David A
authors.initials: DA
authors.lastname: McGuire
mesh_terms: D000293:Adolescent; D000328:Adult; D054544:Arthroplasty, Subchondral; D001781:Blood Component Removal; D002358:Cartilage, Articular / Q000293:injuries / Q000473:pathology / Q000502:physiology*; D003131:Combined Modality Therapy; D015925:Cryopreservation; D005260:Female; D000069585:Filgrastim; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D019650:Hematopoietic Stem Cell Mobilization; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D007270:Injections, Intra-Articular; D007718:Knee Injuries / Q000473:pathology / Q000534:rehabilitation / Q000601:surgery; D007719:Knee Joint / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015915:Motion Therapy, Continuous Passive; D036102:Peripheral Blood Stem Cell Transplantation; D010865:Pilot Projects; D011994:Recombinant Proteins; D012038:Regeneration / Q000502:physiology*; D024162:Second-Look Surgery; D014182:Transplantation, Autologous; D055815:Young Adult
chemical_list: D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D006820:Hyaluronic Acid; D000069585:Filgrastim