title: Low-intensity pulsed ultrasound treatment for postoperative delayed union or nonunion of long bone fractures.
abstract: BACKGROUND
  Postoperative delayed union and nonunion is the most common complication in fracture treatment. Recent studies have shown an accelerating effect of low-intensity pulsed ultrasound (LIPUS) on fracture repair. However, the indications for delayed union and nonunion are not clear. To clarify the factors which influence the effects of LIPUS, the data from a previous prospective multicenter study on LIPUS treatment for postoperative delayed union and nonunion of long bone fractures were reanalyzed.
  
  
  METHODS
  Seventy-two cases of long bone fracture, including those of the femur, tibia, humerus, radius, and ulna, were analyzed. The mean time from the most recent operation to the beginning of LIPUS treatment was 11.5 (3-68) months. The relationship between the background factors and the union rate was analyzed using a logistic regression method. In addition, long bone fractures in an upper extremity or in a lower extremity were analyzed separately.
  
  
  RESULTS
  The union rate was 75% in all the cases of long bone fracture. There was a significant relationship between the union rate and the period from the most recent operation to the beginning of LIPUS treatment in all cases and in those that had long bone fracture of an upper extremity. There was also a significant relationship between the union rate and the time when a radiological improvement was first observed after the beginning of the treatment in all cases and in those with fractures in a lower extremity. When LIPUS treatment was started within 6 months of the most recent operation, 89.7% of all fractures healed. When an improvement in the radiological changes at the fracture site was observed after 4 months in those cases, then the sensitivity and specificity for union were more than 90%.
  
  
  CONCLUSIONS
  LIPUS treatment should be started within 6 months of the most recent operation. Because LIPUS has been shown to be effective without causing either serious invasiveness or any undue risk to the patient, it may be considered the treatment of first choice for cases of postoperative delayed union or nonunion.
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
authors.forename: Seiya
authors.initials: S
authors.lastname: Jingushi
authors.forename: Kosaku
authors.initials: K
authors.lastname: Mizuno
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsushita
authors.forename: Moritoshi
authors.initials: M
authors.lastname: Itoman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005264:Femoral Fractures / Q000000981:diagnostic imaging / Q000628:therapy*; D005500:Follow-Up Studies; D017102:Fracture Healing; D005599:Fractures, Ununited / Q000000981:diagnostic imaging / Q000628:therapy; D006801:Humans; D006810:Humeral Fractures / Q000000981:diagnostic imaging / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011446:Prospective Studies; D011859:Radiography; D011885:Radius Fractures / Q000000981:diagnostic imaging / Q000628:therapy*; D013978:Tibial Fractures / Q000000981:diagnostic imaging / Q000628:therapy*; D016896:Treatment Outcome; D014458:Ulna Fractures / Q000000981:diagnostic imaging / Q000628:therapy*; D014464:Ultrasonic Therapy / Q000379:methods*