title: In vivo characterization of Hyalonect, a novel biodegradable surgical mesh.
abstract: BACKGROUND
  Musculoskeletal reconstructive surgery often requires removal of significant quantities of bone tissue, such as the periosteum, causing critical problems following surgery like friction between different tissues and adhesion of soft tissues to the underlying bone. We studied the long-term host response and closure of large bone defects for periosteal reconstruction using Hyalonect, a novel membrane comprising knitted fibers of esterified hyaluronan, (HYAFF11).
  
  
  METHODS
  For biological characterization, 162 rats were used in a defect model in which a section of the dorsal muscular fascia was removed, and the membrane behavior observed over 540 d using conventional histology, with sham operated rats as controls. In addition, Hyalonect was used to cover defects made in the humeri of 7 dogs, filled with a variety of conventional bone filling compounds, and the regeneration process observed after 6 wks using histology.
  
  
  RESULTS
  Low levels of inflammation were observed in the dorsal muscle fascia defect model, with cellular colonization of the mesh by 30 d, vascularization by 120 days, matrix fiber organization by 270 d, and the appearance of connective tissue identical to the surrounding tissue between 365 and 540 d, without the formation of fibrotic tissue. In addition, Hyalonect was shown to allow the regeneration of bone within the humeral defects whilst preventing fibrotic tissue in-growth, and allowing regeneration of tissue which, by 6 wk, had begun to resemble natural periosteal tissue.
  
  
  CONCLUSIONS
  Hyalonect is suitable for improving the outcome of the final phases of orthopedic and trauma reconstructive surgical procedures, especially in the reconstruction of periosteal tissue.
authors.affiliation: UK Centre for Tissue Engineering, University of Liverpool, Division of Clinical Engineering, Liverpool, UK. npr@liv.ac.uk
authors.forename: Nicholas P
authors.initials: NP
authors.lastname: Rhodes
authors.forename: John A
authors.initials: JA
authors.lastname: Hunt
authors.forename: Cristina
authors.initials: C
authors.lastname: Longinotti
authors.forename: Alessandra
authors.initials: A
authors.lastname: Pavesio
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D001861:Bone Regeneration / Q000502:physiology; D005205:Fascia / Q000473:pathology*; D000071938:Fasciotomy; D005355:Fibrosis / Q000517:prevention & control; D006811:Humerus / Q000502:physiology / Q000601:surgery*; D006820:Hyaluronic Acid / Q000627:therapeutic use*; D008297:Male; D023421:Models, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley; D013526:Surgical Mesh; D016896:Treatment Outcome
chemical_list: D006820:Hyaluronic Acid