for people ages 18 years and up (full criteria)
at UC Davis
study started
estimated completion
Principal Investigator
by Mark Lee (ucdavis)



In order to assess the rate and mode of failure cases observed in patients with distal femur fractures treated with a distal femur plates, anonymized radiographs from those patients will be collected retrospectively. All available images will reviewed by an expert review board in regards to fracture classification, implant and surgery details, quality of initial reduction and plate positioning as well as the occurrence of mechanical complications and the outcome in terms of fracture healing (if available). Additionally, age and gender as basic demographical data will be collected in a de-identified way..

Official Title

A Retrospective Radiological Analysis of the Mechanical Performance of Different Locking Plates in Distal Femoral Fractures


Severely comminuted distal femur fractures can be challenging injuries and usually require surgical treatment with lateral distal plate osteosynthesis. Anatomically pre-contoured locking plates are commonly used. In 2012, the 4.5mm VA-LCP Curved Condylar Plate for distal femur fractures (VA-LCP DF, Synthes) was introduced offering the option of axis variation of the locking screws. Recently, a report highlighted cases of implant failure with this implant, cautioning practicing surgeons against the use of this implant in certain type of AO/OTA fracture and dislocation classification 33 fractures (AO/OTA classification). Based on this report, the current study was designed to perform a retrospective in-depth radiological analysis of all cases distal femur fractures of 4 participating sites in which the VA-LCP DF, the LCP Distal Femur Plate (LCP DF, Synthes) or the 'less invasive stabilization system' for distal femur fractures (LISS DF, Synthes) were used for fracture stabilization. The radiological in-depth analysis will be done by an expert review board with the aim to identify potential causes and risk factors for the failure cases among all cases collected. This evaluation will contribute to a better understanding of the mechanical performance of distal femur fracture plates and the causes and risk factors for failures.


Distal Femur Fracture VA-LCP DF LCP DF LISS DF various angle locking plate Fractures, Bone Femoral Fractures Distal femur plates


For people ages 18 years and up

Inclusion Criteria:

  • Age 18 years and older
  • Diagnosis of a distal femur fracture type OTA/AO classification 33-A, -B, -C
  • uni- or bilateral
  • low or high energy trauma
  • Open or closed fractures
  • Surgical treatment with the VA-LCP DF, LISS DF, LCP DF
  • Available radiographical documentation, beginning with the injury radiographs, ending with the documented healing or any documented failure with or without revision surgery (up to a maximum follow-up of 1 year


  • University of California not yet accepting patients
    Sacramento California United States
  • Kantonsspital Liestal accepting new patients
    Liestal Baselland Switzerland
  • Kantonsspital Graubünden accepting new patients
    Chur Graubünden Switzerland

Lead Scientist at UC Health


accepting new patients
Start Date
Completion Date
AO Clinical Investigation and Publishing Documentation
Study Type
Last Updated