title: A new strategy to enhance artificial ligament graft osseointegration in the bone tunnel using hydroxypropylcellulose.
abstract: OBJECTIVE
  The aim of this study was to determine whether hydroxypropylcellulose (HPC) coating of polyethylene terephthalate (PET) artificial ligaments enhances graft osseointegration in the bone tunnel.
  
  
  METHODS
  Thirty New Zealand white rabbits underwent artificial ligament graft transplantation in the bilateral proximal tibia tunnels. One limb was implanted with an HPC-coated PET graft, and the contralateral limb was implanted with a non-HPC-coated PET graft as a control. The rabbits were then randomly sacrificed at weeks four and eight after surgery for biomechanical testing, histological examination, and histomorphometric and real-time polymerase chain reaction analysis.
  
  
  RESULTS
  At week four after surgery, there were no statistically significant differences in the load to failure or stiffness values between the experimental and control limbs (P = 0.328 and P = 0.128, respectively). At week eight after surgery, the mean load to failure and stiffness value of the experimental limbs was higher than that of the control limbs (P < 0.001 and P = 0.018, respectively). At week eight after surgery, some protruding new bone tissue from the host bone to the graft was found in the HPC-coated group, while a thick fibrous tissue band was observed at the interface between the graft and the host bone in the control group. Histomorphometric analysis showed that the graft-bone interface width in the HPC-coated group was significantly narrower than that in the control group at week eight after surgery (P < 0.001). At weeks four and eight after surgery, the mRNA expression level of bone morphogenetic protein-2 in the HPC group was higher than that in the control group (P = 0.001 and P = 0.010, respectively). The mRNA expression level of osteopontin in the HPC group was higher than that in the control group only at week four after surgery (P = 0.032).
  
  
  CONCLUSIONS
  Our data show that an HPC coating on the surface of PET artificial ligament grafts may induce artificial ligament graft osseointegration in the bone tunnel.
authors.affiliation: Fudan University Sports Medicine Center & Department of Sports Medicine and Arthroscopy Surgery, Huashan Hospital, Fudan University, No. 12, Middle Urumqi Road, Shanghai, 200040, People's Republic of China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Yang
authors.forename: Jia
authors.initials: J
authors.lastname: Jiang
authors.forename: Yuzhuo
authors.initials: Y
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.forename: Ying
authors.initials: Y
authors.lastname: Jing
authors.forename: Peiyi
authors.initials: P
authors.lastname: Wu
authors.forename: Dong
authors.initials: D
authors.lastname: Yu
authors.forename: Shiyi
authors.initials: S
authors.lastname: Chen
mesh_terms: D000818:Animals; D002482:Cellulose / Q000031:analogs & derivatives* / Q000494:pharmacology; D020099:Coated Materials, Biocompatible; D004195:Disease Models, Animal; D008022:Ligaments / Q000637:transplantation*; D008297:Male; D016348:Osseointegration / Q000187:drug effects*; D011093:Polyethylene Terephthalates; D019736:Prostheses and Implants; D011817:Rabbits; D013977:Tibia / Q000601:surgery*
chemical_list: D020099:Coated Materials, Biocompatible; D011093:Polyethylene Terephthalates; D002482:Cellulose; C008079:hydroxypropylcellulose