title: Treatment of distal femoral nonunion and delayed union by using a retrograde intramedullary interlocking nail.
abstract: OBJECTIVE
  To analyze the causes of distal femoral nonunion and delayed union and assess the outcome of the corresponding treatment, retrograde intramedullary interlocking nail (RIIN).
  
  
  METHODS
  From June 1995 to December 1998, 15 patients (9 males and 6 females) with distal femoral nonunion and delayed union were treated with RIIN. The average age of the patients was 34.5 years (23-46 years). Bone grafting was performed in 10 patients, closed reaming was done in the other 5 patients. Correction osteotomy was performed in 2 patients, and intra-articular release of knee adhesion in 11 patients. X-ray examination and knee society clinical rating system (KSS) were used to evaluate the results.
  
  
  RESULTS
  All fractures were followed up for at least 9 months with average follow-up duration of 14.5 months (9-33 months). Solid union was documented in all patients at 6.4 months on average. There were no infections or malunions in this series. Based on the final follow-up data, acceptable functional range of motion (ROM) of over 90 degrees was achieved in most patients. The average ROM was 93.5 degrees with significant improvement of 28 degrees (42.7%, P<0.05) compared with the preoperative ROM. The average knee score was 96. Excellent ROM emerged in 13 patients. The knee function score was 90.5 on average.
  
  
  CONCLUSIONS
  The main causes of distal femoral nonunion and delayed union are improper indications and improper use of the implants. RIIN is an effective alternative for treatment of distal femoral nonunion and delayed union because it can provide a stable and reliable fixation which is beneficial for early functional exercise of knee. Bone grafting, closed reaming and intra-articular release of knee adhesion should be considered in order to enhance the bone healing and improve ROM and the knee function.
authors.affiliation: Department of Orthopaedics, Shanghai 6th People's Hospital, Shanghai 200233, China.
authors.forename: X
authors.initials: X
authors.lastname: Zhang
authors.forename: B
authors.initials: B
authors.lastname: Zhong
authors.forename: S
authors.initials: S
authors.lastname: Sui
authors.forename: X
authors.initials: X
authors.lastname: Yu
authors.forename: Y
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000328:Adult; D001858:Bone Nails; D016025:Bone Transplantation; D005260:Female; D005264:Femoral Fractures / Q000601:surgery*; D005594:Fracture Fixation, Intramedullary / Q000295:instrumentation; D005599:Fractures, Ununited / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010027:Osteotomy