title: Regenerated soft tissue survival using repulsive force of magnetized devices: preliminary report.
abstract: BACKGROUND
  Large full-thickness cartilage defects in the weight-bearing area are difficult to treat. A new therapeutic strategy called the total joint regeneration (TJR) system is proposed for such large defects. The purpose of this study was to evaluate the effects of the magnet-type TJR device using a rabbit model.
  
  
  METHODS
  The magnetized devices were implanted in full-thickness chondral defects on the patellofemoral joints of rabbits. The specimens and surrounding tissue were harvested 4 weeks after the surgery and observed macroscopically and histologically. The thickness of the regenerated soft tissue on the femur joint surface was measured and compared. The difference between the two groups (magnetized and nonmagnetized) was significant at P < 0.05.
  
  
  RESULTS
  Some cartilaginous regeneration was seen in the repair tissue. However, about half of the experimental knees were omitted from the study because of some trouble, such as loosening of the device or patella fracture.
  
  
  CONCLUSIONS
  This study suggested that magnetized devices were useful for regenerating soft tissue by maintaining the joint space. Some hyaline cartilage-like tissue was regenerated partially on the magnetized devices. It was suggested that these devices might be useful for cartilage regeneration if the devices are improved.
authors.affiliation: Department of Orthopaedic Surgery, Nara Medical University, Kashihara, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Seto
authors.forename: Naohide
authors.initials: N
authors.lastname: Tomita
authors.forename: Yasuji
authors.initials: Y
authors.lastname: Harada
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Sakoda
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Takakura
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000293:injuries / Q000502:physiology*; D008280:Magnetics / Q000295:instrumentation*; D008297:Male; D010865:Pilot Projects; D011817:Rabbits; D012038:Regeneration / Q000502:physiology*; D016474:Weight-Bearing